- Email: [email protected]
Levels of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in fish species from Kahramanmaras, Turkey
Environment International 31 (2005) 703 – 711 www.elsevier.com/locate/envint
Levels of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in fish species from Kahramanmaras, Turkey ¨ zlem Erdogrula, Adrian Covacib,T, Paul Schepensb O a
Department of Food Science and Technology, Faculty of Agriculture, University of Kahramanmaras Su¨tc¸u¨ Imam, Kahramanmaras, Turkey b Toxicological Center, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium Received 2 November 2004 Available online 7 March 2005
Abstract The levels of organohalogenated contaminants, such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in four fish species (Acanthobrama marmid (kalashpa), Cyprinus carpio (carp), Chondrostoma regium (nose-carp), and Silurus glanis (wels)) from the Sir Dam Lake, Kahramanmaras, Turkey. These species were selected for their characteristic feeding behaviour and their importance to local human fish consumption. DDTs were the predominant organohalogenated contaminants in all species, with the p,pV-DDE contributing to more than 90% to the total DDTs. Other OCPs, such as hexachlorocyclohexane (HCH) isomers, chlordanes and hexachlorobenzene (HCB) were found at much lower levels in all five species. The levels of PCBs and PBDEs (on wet weight basis) were lower than in similar species from European or American freshwater systems. PBDE data were measured for the first time in fish species from Turkish environment. Lipid-based concentrations of OCPs, PCBs and PBDEs were higher in wels than in the other species and this was related to its piscivorous feeding mode and to its higher lipid content. Contrarily, concentrations of pollutants in nose-carp were the lowest, in agreement with its more herbivorous diet. A preferential accumulation in muscle compared to liver was observed for all OCPs, PCBs, and PBDEs in wels and carp, while in nose-carp, a preferential accumulation in liver was observed only for PBDEs, p,pV-DDT and PCBs. Racemic amounts for a-HCH were measured in all investigated muscle and liver samples, except for carp muscle. D 2005 Elsevier Ltd. All rights reserved. Keywords: Fish; Polychlorinated biphenyls; Organochlorine pesticides; Polybrominated diphenyl ethers; Turkey
1. Introduction The production and intensive agricultural or industrial use of persistent organohalogenated pollutants (POPs), such as organochlorine pesticides (OCPs) or polychlorinated biphenyls (PCBs), have led to the widespread contamination of the environment. Polybrominated diphenyl ethers (PBDEs) have come into extensive use as flame retardant additives to plastics, textiles, electronics and paints (de Boer et al., 2000). Due to their persistence, lipid solubility, and
T Corresponding author. Fax: +32 3 820 2722. E-mail address: [email protected] (A. Covaci). 0160-4120/$ - see front matter D 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.envint.2005.01.002
structural similarity to PCBs, PBDEs are emerging as a new class of environmental contaminants (de Boer et al., 2000; Darneurd et al., 2001). Being lipophilic, POPs are characterised by a high bioaccumulation potential in food chains and therefore may pose a serious threat to upper trophic levels of aquatic communities (Fisk et al., 2001; Boon et al., 2002; Falandysz et al., 2002). In biological systems, several of these chemicals are potentially carcinogenic and may cause alternations in endocrine, reproductive and nervous systems (Cogliano, 1998; Brouwer et al., 1999; Darnerud, 2003; Langer et al., 2003). For these reasons, most countries have restricted or banned the use of PCBs and OCPs. However, the environmental persistence of POPs, along with the large
704
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
volume usage of these compounds in the past (for PCBs and OCPs) and in the present (for PBDEs), suggests that they could remain a serious environmental problem for a number of years. Fish is a suitable indicator for the environmental pollution monitoring because they concentrate pollutants in their tissues directly from water, but also through their diet, thus enabling the assessment of transfer of pollutants through the trophic web (Fisk et al., 2001; Boon et al., 2002). Data on the presence and distribution of organohalogenated contaminants in fish and especially edible fish species are therefore important not only from ecological, but also human health perspective. Humans are exposed inadvertently to POPs through numerous sources, of which the consumption of contaminated fish is one of the most important pathways (Fqrst, 1993). In Turkey, OCPs have been used since 1945, with large quantities of these chemicals being used during the 1960s and 1970s. Since 1983, the usage of OCPs has been severely restricted or banned (C ¸ ok et al., 1997). Only few studies have investigated the presence of OCPs in Turkish aquatic environment, where they have been evidenced in relatively high concentrations (Ayas et al., 1997; Coelhan and Barlas, 1998; Barlas, 1999). The principal aim of this study was to investigate the levels of organohalogenated contaminants in several fish species from Sir Dam Lake (Kahramanmaras, Turkey), an artificial lake with great economical importance for the
region. Additionally, the distribution of pollutants, including the a-HCH enantiomers, between muscle and liver was also investigated.
2. Materials and methods 2.1. Study area The Ceyhan river basin is located in the eastern Mediterranean region of Turkey and drains into the Mediterranean Sea in the South (Fig. 1). It covers 20 670 km2 spread over three major provinces (Kahramanmaras, Osmaniye and Adana) and has a potential of up to 590 000 ha of irrigable land. Sir Dam Lake, with a surface of 4750 ha and a maximum capacity of 10 120 hm3, was constructed between 1987 and 1991 and is the 2nd important dam in the Ceyhan river basin. The dam aimed to irrigate approximately 100 000 ha of land, to generate electrical power and to reduce the occurrence of floods. Agricultural production in the region is dominated by cotton (~50%) and wheat (36%), followed by groundnuts, maize, fodder, rice and watermelon. Annual fish production was estimated at approximately 86 ton in 1997. Several potential sources of pollution are present around the lake and they include not only paper, textile, oil and milk industries, but also waste from slaughterhouses or household.
Fig. 1. The map of sampling site showing the Sir Dam Lake (Kahramanmaras, Turkey).
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
705
land) was used for the extraction of target compounds from tissues.
2.2. Sampling A total of 80 individual fishes, representing 4 species Acanthobrama marmid (A) (kalashpa), Cyprinus carpio (C) (carp), Chondrostoma regium (Co) (nose-carp), and Silurus glanis (S) (wels), were obtained from fishermen along the Sir Dam Lake. The first 3 species belong to the Cyprinidae family and are benthopelagic fishes with an omnivorous feeding mode (insect larvae, crustaceans, annelids, plants and molluscs), except for the nose-carp with a more herbivorous diet (phytoplankton and zooplankton). Wels belongs to the Siluridae family and is mainly carnivore with its main diet composed of fish, amphibians, and small aquatic animals. Fishes were caught between January and June 2003. The length of the fish was measured from the front-tip of the mouth to the beginning of the caudal fin (standard length). Information on the length, weight, and age is given in Table 1. Only the excised muscle and liver samples were collected and they were stored at 20 8C until analysis. 2.3. Materials The organochlorine pesticides under investigation were hexachlorobenzene (HCB), p,pV-DDE, p,pV-DDD, o,pV-DDT and p,pV-DDT (expressed as DDTs), a-, h-, g- isomers of hexachlorocyclohexane (expressed as HCHs), oxychlordane (OxC), trans-nonachlor (TN), trans-(TC) and cis-chlordane (CC) (expressed as CHLs). The following polychlorinated biphenyl (PCB) congeners tri (28), tetra (74), penta (99, 101, 105, 118), hexa (128, 138, 153, 156), hepta (170, 180, 183, 187), octa (194 and 199) were targeted. Brominated flame retardants included polybrominated diphenyl ethers (PBDEs) congeners 28, 47, 99, 100, 153, 154 and 183 and brominated biphenyl (BB) 153. All individual standards of OCPs, PCBs and PBBs were obtained from Dr. Ehrenstorfer Laboratories (Augsburg, Germany), while PBDE standards were available from Wellington Laboratories (Guelph, Canada). Acetone, nhexane, dichloromethane and iso-octane were of pesticide grade (Merck, Germany). Anhydrous sodium sulphate and silica gel (Merck) were used after heating overnight at 120 8C. An accelerated Soxhlet extractor B-811 (Buchi, Switzer-
2.4. Methods The methods used for sample preparation and analysis have been previously described and validated (Covaci et al., 2002a, 2004; Voorspoels et al., 2003) and are presented briefly below. 2.5. Sample preparation Approximately 3 g fish tissue was ground with anhydrous sodium sulphate and placed into a hexane-prewashed extraction thimble. Internal standards (10 ng of PCB 46 and PCB 143, 7.5 ng of E-HCH, 2 ng of BB 103 and 0.5 ng of BB 155) were added and the mixture was extracted for 2 h with 75 ml hexane/acetone=3:1 (v/v) with a hot Soxhlet manifold. After concentration to approximately 5 ml, an aliquot (~1/6 of the extract) was used to determine the lipid content by evaporating the solvent at 105 8C for 1 h. The rest of the extract was subjected to clean-up onto a cartridge containing ~8 g silica impregnated with concentrated sulfuric acid (44%). Complete elution of OCPs, PCBs, and PBDEs was done with 15 ml n-hexane followed by 10 ml dichloromethane. The final eluate was concentrated with a rotary-evaporator and further under nitrogen to near dryness. The extract was solubilized in 80 Al iso-octane and analysed for POPs (see below). For the analysis of a-HCH enantiomers, previously obtained extracts were fractionated on a silica SPE cartridge (500 mg, 3 ml, Supelco, Bornem, Belgium). After loading the extract, the 1st fraction, containing all PCBs, p,pV-DDE and p,pV-DDT, was eluted with 4 ml hexane, while the 2nd fraction containing all HCH isomers and p,pV-DDD, was eluted with 3 ml dichloromethane and concentrated to 50 Al. 2.6. Instrumentation Chromatographic conditions have been previously described in detail (Covaci et al., 2002a, 2004; Voorspoels et al., 2003).
Table 1 Biometric data and lipid concentrations in muscle and livers from 4 fish species from Turkey Tissue
Acanthobrama marmid Cyprinus carpio (carp) Chondrostoma regium (nose-carp) Silurus glanis (wels)
N
Lipids (%)
Weight (g)
Standard length (mm)
Age (years)
Mean/median
Range
Mean/median
Range
26–101
13/13
12–17
2.1/2
1–4
400–1834
36/36
25–43
6.3/7
4–8
120/107
52–246
19/18
15–24
4/4
2–6
2520/653
194–31000
55/45
33–151
1.4/1
1–4
Mean/median
Range
Mean/median
24
1.74/1.60
0.69–4.04
43/30
Muscle Liver Muscle Liver
17 8 17 3
0.66/0.34 5.72/5.51 1.63/1.63 7.95/7.39
0.21–2.63 3.31–8.67 0.50–3.56 3.94–12.52
1145/1180
Muscle Liver
22 8
2.22/0.95 3.63/3.03
0.30–11.53 2.11–6.07
Range
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
706
2.6.1. PCBs One microliter extract was injected in pulsed splitless mode into a Hewlett Packard 6890 gas chromatograph (GC) with electron capture detector (A-ECD) equipped with a 50 m0.22 mm0.25 Am, HT-8 capillary column (SGE, Zulte, Belgium). 2.6.2. PBDEs One microliter extract was injected in cold splitless mode into a GC coupled to a HP 5973 mass spectrometer (MS) operated in the electron-capture chemical ionization (ECNI) in SIM mode (monitored ions m/z=79 and 81) and equipped with a 25 m0.22 mm0.25 Am, HT-8 capillary column. The ion source, quadrupole and interface temperatures were 250, 150 and 300 8C, respectively. 2.6.3. OCPs The same system used for PBDEs was employed for the analysis of OCPs, but using other conditions. The ion source, quadrupole and interface temperatures were 150, 150 and 300 8C, respectively. One microliter of the extract was injected in pulsed splitless mode and two specific ions for each pesticide were monitored in pre-defined windows according to their retention times. 2.6.4. Enantioselective analysis The 2nd fraction resulted from silica fractionation was analysed by GC/ECNI-MS using a 30 m0.25 mm0.25 Am Chirasil-Dex column (Chrompack, Middelburg, The Netherlands). A volume of 35 Al of the extract was injected in solvent vent injection mode. Ion source and quadrupole temperatures were 150 8C and 150 8C, respectively. Three ions (255, 253 and 71) were monitored for a-HCH. The enantiomeric ratio (ER) was defined as the ratio of peak area of the first ((+) a-HCH) to the second eluting enantiomer (() a-HCH). The elution order of the two enantiomers was checked with enantioenriched standards (Dr. Ehrenstorfer, Augsburg, Germany). A good reproducibility (RSD b1.5%) for injections of standard solutions allowed the determination with sufficient significance of minor changes in ERs. The enantiomeric fraction (EF) was defined as ER/(ER+1). ER ¼
AðþÞaHCH AðÞaHCH
EF ¼
ER : 1 þ ER
2.7. Quality assurance Multi-level calibration curves were created for the quantification and good linearity (r 2N0.999) was achieved for tested intervals that included the whole concentration range found in samples. The analyte identification was based on their relative retention times (RRT) to the internal standard used for quantification (for ECD) and on retention times, ion chromatograms and intensity ratios of the monitored ions for GC/MS. A deviation of the ion intensity
ratios within 15% of the mean values of the calibration standards was considered acceptable. Peak area ratios (analyte response/internal standard response) were plotted against the concentration ratios (analyte concentration/ internal standard concentration). Method limits of quantification (LOD) for individual OCPs, PCB and PBDE congeners ranged between 0.02 and 0.1 ng/g wet weight (ww). Recoveries for target analytes varied between 75 and 104 (RSD b12%). The method performance was assessed through rigorous internal quality control, which included daily check of calibration curves, regular analysis of procedural blanks and certified materials CRM 349 (PCBs in cod liver oil) and CRM 430 (OCPs in pork fat). The method was tested by participation in an interlaboratory test organised by the Institute for Reference Measurements and Materials (IRMM, Geel, Belgium). Seven PCB congeners (nos. 28, 52, 101, 118, 138, 153 and 180) were determined in nonspiked, medium- and high-level spiked pork fat. The results of the individual PCB congeners deviated less than 10% from the target values (Bester et al., 2002). For PBDEs, the participation to the second interlaboratory test (de Boer et al., 2002) on PBDE (which included fish tissue) showed a variation of less than 10% from mean values obtained from 42 participating laboratories. To evaluate the accuracy of EF measurements for a-HCH enantiomers, a standard reference material (SRM 1945, whale blubber) was analysed. The EF found for the a-HCH enantiomers (0.583F0.004, n=3), compares favourably with the value of 0.574F0.007 (n=5) found by Wong et al. (2002). 2.8. Statistical analysis All statistical analyses were completed with STATISTICA for Windows (StatSoft, Tulsa, OK, USA). Due to relative large dispersion of values, the concentrations of pollutants in fish muscle and liver are summarised using medians together with minimum and maximal values. Values below LOQ were set to zero. The distribution of the organohalogenated compounds was not normal (Shapiro–Wilks test, pN0.05) and therefore non-parametric statistics were employed. The levels of contamination between species were compared using non-parametric Kruskal–Wallis tests. Comparison of profiles and concentrations between liver and muscle was performed by using Wilcoxon non-parametric tests. Finally, all performed correlations were carried out using non-parametric Spearman Rank correlation. The level of significance was set at a=0.05 throughout this study.
3. Results Lipid concentrations in muscle and liver from 4 fish species from Sir Dam Lake are showed in Table 1. Lipid
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
707
Table 2 Concentrations of organohalogenated pollutants (expressed in ng/g wet weight) in muscle of selected fish species from Turkey Acanthobrama marmid (n=24) BDE 28 BDE 47 BDE 99 BDE 100 BDE 153 BDE 154 Sum BDEs Sum PCBs HCB a-HCH h-HCH g-HCH Sum HCHs Oxychlordane Trans-nonachlor Trans-chlordane Cis-chlordane Sum CHLs p,pV-DDE p,pV-DDD p,pV-DDT Sum DDTs
Cyprinus carpio (n=17)
Chondrostoma regium (n=17)
Silurus glanis (n=22)
Range
Median
Range
ND–1.07 ND–0.10 ND–0.12 ND–0.08 ND–0.11 ND–1.5 ND–10.0 0.05–0.34 ND–0.10 0.02–0.19 ND–0.22 0.02–0.33 ND–0.05 ND–0.30 ND–0.20 0.01–0.18 0.02–0.72 7.7–233 0.65–12.1 ND–0.74 8.4–246
ND 0.33 0.03 0.04 0.02 0.03 0.50 3.4 0.19 0.13 0.09 0.16 0.43 ND 0.07 0.06 0.05 0.17 50.2 3.2 0.62 53.8
ND–0.13 0.05–5.3 ND–0.15 ND–0.50 ND–0.28 ND–0.38 0.06–6.7 0.39–42.3 0.05–1.5 0.02–1.1 ND–0.46 ND–1.1 0.13–2.2 ND–0.21 0.03–1.4 0.02–1.1 0.02–0.91 0.07–3.6 20.2–901 1.3–54.3 0.02–4.5 22.1–960
Median
Range
Median
Range
Median
ND 0.54 ND 0.04 0.04 0.03 0.67 3.0 0.16 0.05 0.06 0.05 0.22 ND 0.13 0.12 0.08 0.35 73.5 5.3 0.13 77.4
ND–0.05 0.14–1.2 ND–0.06 0.02–0.11 ND–0.07 ND–0.13 0.18–1.6 ND–12.4 0.08–0.45 0.02–0.13 0.03–0.19 ND–0.55 0.08–0.65 ND–0.09 0.03–0.52 0.04–0.71 0.02–0.34 0.09–1.7 22.1–273 1.9–16.6 ND–0.55 24.1–290
ND 0.13 0.02 ND ND ND 0.15 0.94 0.07 0.03 0.03 0.07 0.21 ND 0.02 0.02 0.01 0.05 13.3 0.82 0.08 14.4
ND–0.16 ND–1.06 ND–0.06 ND–0.06
ND 0.07 ND ND ND ND 0.08 0.39 0.11 0.04 0.04 ND 0.08 ND 0.03 0.02 0.02 0.08 32.3 2.3 0.09 34.8
ND–0.10 0.02–1.3 ND–4.8 0.03–0.41 0.02–0.40 0.02–0.24 ND–0.67 0.04–0.75 ND–0.10 ND–0.87 ND–0.19 ND–0.20 ND–1.4 4.0–156 0.35–13.0 ND–1.23 4.5–170
percentages in muscle are similar for kalashpa, nose-carp, and wels, but are higher ( pb0.01) than lipid percentages in carp and barbel. Lipid percentages in the liver of carp, nosecarp and wels are higher than the corresponding lipid percentages in muscle. Liver lipid percentages in wels are significantly lower ( pb0.05) than in carp and nose-carp. Concentrations of organohalogenated pollutants, expressed in ng/g ww in muscle of selected fish species from Sir Dam Lake are showed in Table 2 and concentrations of organohalogenated pollutants, expressed in ng/g lipid weight (lw) in muscle and liver in Table 3. All muscle and liver samples contained HCB, a-HCH, p,pV-DDD and p,pV-DDE, while the other organochlorine pesticides were detected with a lesser frequency. DDTs were the prevalent organohalogenated contaminants found in the investigated fish species from Sir Dam Lake. The median levels of sum DDTs in kalashpa, carp,
nose-carp and wels muscle samples were 77.4, 14.4, 34.8 and 53.8 ng/g ww, respectively (Table 2). The dominant metabolite was p,pV-DDE, which constituted 93–95% of the sum DDTs for each species, followed by p,pV-DDD (5–7%) and p,pV-DDT (b0.5%). The median concentrations of p,pVDDE in kalashpa, carp, nose-carp and wels muscle samples were 73.5, 13.3, 32.3, 50.2 ng/g ww, respectively, while the median levels of p,pV-DDE in liver of carp, nose-carp and wells were 193, 317, 119 ng/g ww, respectively. The a-HCH isomer was found in 100% of fish samples, while the h- and g-HCH isomers were found in 98 and 66% samples, respectively. The median levels of sum HCHs in muscle of kalashpa, carp, nose-carp and wels were 0.22, 0.21, 0.08 and 0.43 ng/g ww, respectively (Table 2). The three HCH isomers were present in different proportions in the fish species, with slightly higher contribution of g-HCH in carp.
Table 3 Concentrations of organohalogenated pollutants (expressed in ng/g lw) in muscle and liver of selected fish species from Turkey (see Sampling for fish species identification) A N Sum HCHs Sum CHLs Sum DDTs Sum PCBs Sum PBDEs
Median Range Median Range Median Range Median Range Median Range
C muscle
C liver
Co muscle
Co liver
S muscle
S liver
24
17
8
17
3
22
8
16 6–41 22 8–41 4993 2214–7170 271 76–400 34 11–110
30 9–159 16 2–74 3866 1321–10023 165 2–486 34 7–597
23 11–108 10 6–23 3327 550–5297 73 14–243 39 ND–68
8 4–20 6 3–28 3210 1687–9520 42 2–387 9 ND–62
11 9–24 15 8–41 2753 2220–4667 144 50–200 44 17–163
31 10–144 20 11–70 5800 2470–18171 312 70–887 39 10–183
35 1–55 9 5–17 3338 2260–4673 123 28–289 34 6–52
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
708 45
kalashpa 40
carp-M 35
carp-L 30
%PCB
nose-carp-M 25
nose-carp-L 20
wels-M
15
wels-L
10 5 0 28
74
101
99
118
153
105
138
187
183
128
156
180
199
170
194
PCB congener Fig. 2. Mean PCB percentage in muscle (M) and liver (L) from investigated fish species from Sir Dam Lake, Turkey. For species identification, see Sampling.
The median concentrations of sum CHLs in the 4 fish species were at similar levels with HCH isomers (Table 2), with the highest values found for kalashpa and wels (0.35 and 0.17 ng/g ww, respectively). The highest contributor to the sum CHLs was trans-nonachlor followed by transchlordane. Oxychlordane had a higher detection frequency in wells, but never higher than 40%. PCB concentrations were also determined in the selected fish muscle and liver samples. The median levels of sum PCBs in kalaspha, carp, nose-carp and wels muscle samples were 3, 0.94, 0.39, 3.4 ng/g ww, respectively (Table 2). For all species, the PCB profile was dominated by the tri- to penta-CB isomers, which constituted between 53% and 90% of the total PCBs (Fig. 2). The most persistent PCB congeners (nos. 138, 153 and 180) were present in higher percentage in kalashpa, but with a much lower contribution to sum PCBs than reported for similar species from other worldwide locations (Svobodova` et al., 1995; Covaci et al., 2002b). PBDEs were detected in all muscle and liver samples, except few samples of carp liver and nose-carp muscle. The PBDE levels were lower than the PCB levels, but they were
Table 4 Distribution of organohalogenated contaminants between liver and muscle of carp, nose-carp and wels, expressed as c liver/(c muscle+c liver), concentration expressed per lipid weight
1000.0
Concentration (ng/g ww)
at the same level or higher than some OCPs, such as HCB, HCHs and CHLs. The median levels of sum BDEs in kalashpa, carp, nose-carp and wels muscle samples were 0.67, 0.15, 0.08 and 0.50 ng/g ww, respectively. BDE 47 was the dominant congener in all muscle and liver samples. PBB 153 was not found in any samples, indicating the very limited usage of Firemaster technical mixtures of PBBs in Turkey. Concentrations of pollutants (in ng/g ww) were significantly related to the lipid percent (Fig. 3) and the best correlations were obtained for p,pV-DDE and p,pV-DDD (R 2=0.793 and 0.780, pb0.05, respectively). The distribution of organohalogenated contaminants between liver and muscle was assessed through the calculation of the accumulation ratio c liver/(c muscle+c liver), where concentrations were expressed in ng/g lw. Values lower than 0.50 indicate a preferential accumulation in the muscle. A preferential accumulation in muscle compared to liver was observed for all OCPs, PBDEs and PCBs for wels and carp, while for nose-carp, a preferential accumulation in liver was observed for only PBDEs, p,pV-DDT and PCBs (Table 4).
100.0 p,p'-DDE
10.0
PBDEs
Cyprinus carpio (carp) (n=8)
Chondrostoma regium (nose-carp) (n=3)
Silurus glanis (wels) (n=8)
0.34F0.13 0.33F0.12 0.38F0.11 0.46F0.10 0.48F0.09 0.45F0.29 0.25F0.11 0.38F0.22
0.55F0.14 0.46F0.16 0.49F0.07 0.48F0.13 0.50F0.09 0.62F0.26 0.57F0.11 0.58F0.22
0.39F0.06 0.36F0.09 0.41F0.07 0.36F0.06 0.40F0.08 0.33F0.12 0.24F0.08 0.33F0.14
HCB
1.0
p,p'-DDD PCBs
0.1 0.0 0.1
1.0
10.0
100.0
% Lipid Fig. 3. Relationships between concentrations of pollutants (ng/g ww) and lipid percentage.
a-HCH h-HCH HCB p,pV-DDE p,pV-DDD p,pV-DDT PCBs PBDEs
Values lower than 0.50 indicate a preferential accumulation in the muscle.
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711 Table 5 Mean and standard deviations of enantiomeric ratios (ERs) and enantiomeric fractions (EFs) of a-HCH in liver and muscle of Acanthobrama marmid (A), Cyprinus carpio (C), Chondrostoma regium (Co), and Silurus glanis (S) A muscle (n=3) Co muscle (n=2) C muscle (n=2) S muscle (n=3) Co liver (n=2) C liver (n=2) S liver (n=3)
ERFS.D.
EFFS.D.
1.022F0.033 0.971F0.071 0.930F0.043 0.982F0.023 1.013F1.013 1.004F0.012 1.008F0.013
0.505F0.008 0.492F0.018 0.482F0.012 0.496F0.006 0.503F0.012 0.501F0.003 0.502F0.003
Racemic enantiomeric fractions for a-HCH were determined in muscle of kalashpa, nose-carp and wels and in liver of carp, nose-carp and wels (Table 5). Non-racemic values could be determined only in muscle of carp.
4. Discussion Due to their known persistency, liposolubility and bioaccumulation in species at higher trophic levels, organohalogenated contaminants, such as OCPs, PCBs and PBDEs, are necessary to be monitored in the environment and with a special attention for animal species which may be part of the human food. Several fish species representative for the human fish consumption in the Kahramanmaras region were selected for investigation of their contamination with POPs. Relatively low concentrations of organohalogenated pollutants were found in the fish samples with the most abundant pollutant in all fish samples being p, pV-DDE, the main metabolite of p,pV-DDT. The concentrations of DDTs in carp samples were in the same range with those reported by Ayas et al. (1997) for carp from the Gfksu Delta, but were lower than those reported by Barlas (1999) for the Upper Sakarya basin. Due to (bio)transformation kinetics, the p, pV-DDE/ p, pV-DDT ratio increases with time after the exposure to p, pV-DDT has ceased or was diminished through restricting regulations. In our study, the mean p, pV-DDE/ p, pV-DDT ratio in the muscle of the five investigated species ranged from 100 to 650 and can be correlated with past exposure to DDT (high p, pV-DDE content) and with low present exposure to DDT (low p,pVDDT levels). Another metabolite of DDT, p,pV-DDD, was also found, but in lower amounts than p,pV-DDE. The levels of a-, h- and g-HCH isomers in the fish species from Sir Dam Lake are lower than values found by Barlas (1999) in the Sakarya basin suggesting different pollutant factors in the two aquatic environments. None of the three HCH isomers was predominant in the investigated fish species. Although the usage of HCB has been severely restricted in Turkey since 1959, all analysed fish samples contained low, but detectable residues of HCB. This low level of
709
contamination can have its origin in the various industrial processes from which HCB can be emitted as a by-product in high-temperature processes. HCB may also be present as impurity in other chlorinated pesticides and, most probably, it is related to the long-range air transport from more contaminated areas of Europe (Jaward et al., 2004). PCBs were used as coolant/dielectrics in transformers, capacitors and other electrical equipment in several countries, including Turkey. Between 1970 and 1982, a combination of transformer oil and lindane (g-HCH) (48+4%) was widely used as pesticide in Turkey (C ¸ ok et al., 2003). The usage of PCBs in closed systems was restricted in Turkey since 1983, while their use in open applications was banned only in 1996 (C ¸ ok et al., 2003). However, the exposure to PCBs can still occur through the disposal of PCB-containing equipment and through the refilling and repairing of closed applications, for which there are no strict regulations (C ¸ ok et al., 2003). The contamination degree with PCBs of the fish samples from the Sir Dam Lake is lower or similar to PCB levels found in other countries. Mean PCB concentrations found by Svobodova` et al. (1995) in carp and wels muscle from Czech Republic were 3 and 17 ng/g ww. Carp and wels from the Danube Delta (Covaci et al., 2002b) contained PCB levels ranging from 3.5 to 18 ng/g ww and from 0.5 to 2.0 ng/g ww, respectively. The PCB levels in the fish species from Sir Dam Lake are also below the tolerance limits for human consumption set for freshwater fish from European countries (1.4 Ag/g ww in Germany). The distribution of PCB congeners in the fish species from Sir Dam Lake (Fig. 2) show an exclusive contamination with low chlorinated PCB congeners (mainly composed of triand tetra-CB congeners), which together with the low PCB concentrations measured in fish suggest a diffuse contamination through the water column in which these congeners have a higher solubility. The PBDE levels, which were measured for the first time in fish species from Turkish aquatic systems, had a maximum value of 6.7 ng/g ww found in a wels sample and were low compared to values found in freshwater fish from USA or Europe. Johnson and Olson (2001) found that total PBDE concentrations ranged from 1.4 to 1250 ng/g ww found in a whitefish collected in an urbanised area of the Spokane River, with most of the data being in the 20– 300 ng/g ww range. Dodder et al. (2002) reported levels ranging from 6.9 to 18 ng/g ww for various fish species, such as smelt, blue gills, crappie from locations with low PBDE contamination and higher levels (up to 65 ng/g ww) in carp fish collected from a near PBDE manufacturing facility. Loganathan et al. (1995) found carp in the Buffalo River to have levels ranging from 13 to 23 ng/g ww for total PBDEs. BDE 47 was clearly the predominant BDE congener in the fish samples, in accordance with its previously reported selective bioaccumulation (de Boer et al., 2000). Despite the present low concentrations of PBDE in fish, the vicinity of textile industry close to the Sir Dam
710
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
Lake may constitute a potential source of PBDEs and therefore, concentrations of PBDEs in fish may increase in time. For all compounds, lipid-based concentrations (Table 3) were higher in wels than in other species, in accordance with its feeding mode. Contrarily, concentrations of pollutants in nose-carp (Table 3) were the lowest, which agrees with its more herbivorous feeding mode. Being significantly correlated, the lipid percentage is a good predictor for the concentrations of POPs expressed per wet weight (Fig. 3). The best correlations were obtained for p,pV-DDE and p,pVDDD (R 2=0.793 and 0.780, pb0.05, respectively), which are the major organohalogenated contaminants in the Sir Dam Lake. Interestingly, similar slopes for the equation lg(conc. ng/g ww)=f(lg lipid%) were obtained for p,pV-DDE and p,pV-DDD (1.142 and 1.121, respectively), suggesting a similar rate of bioaccumulation. PCBs and PBDEs had the smallest correlation coefficients (R 2=0.355 and 0.331, pb0.05, respectively) suggesting that the high variation in concentrations is due to non-uniformly distributed sources. For carp and wels, residues of all pollutants were detected at higher levels in muscle than in liver (Table 4). Svobodova` et al. (1995) has also observed higher concentrations of DDT and its metabolites in muscle of wels compared to liver (expressed per lw). Contrarily, nose-carp showed a preferential accumulation of pollutants in the liver (Table 4). Burreau et al. (2000) have observed that BDE 47 accumulated in lipid rich tissues in pike (lean fish) and this includes liver (b10%) and perivisceral adipose tissue. With exception of sole, Voorspoels et al. (2003) have also observed a preferential accumulation of PBDE congeners in liver (containing up to 50% lipids) of marine lean fish, such as plaice, bib and whiting. EF values of a-HCH in muscle of fish species from the Turkish environment were racemic for kalashpa, nose-carp, and wels and non-racemic for carp (Table 5), suggesting species-dependent stereospecific bioprocesses. Similar trends were observed for EFs of a-HCH isomers in muscle of carp and wels samples from the Danube Delta (Covaci et al., 2003), for which EF values were 0.465 (n=2) and 0.489 (n=6), respectively. Racemic amounts of a-HCH have also been measured in trout muscle from Lake Michigan (Wong et al., 2002) and whole cod from the Baltic Sea (Wiberg et al., 2000), Northwater Polynya (Moisey et al., 2001) or Arctic (Hoekstra et al., 2003), where it was also the most predominant HCH isomer. Interestingly, EFs measured in all liver samples from nosecarp, carp and wels were racemic, observation which is in accordance with racemic amounts of a-HCH measured in cod liver oil (Wong et al., 2002).
Acknowledgements The Scientific and Technical Research Council of Turkey (TUBITAK) supported this study (NATO B-2). All of the
fish samples were obtained through the assistance of Orhan Bqlbql (Ministry of Agriculture and Rural Affairs of Kahramanmaras, Turkey) and were prepared by Cengiz Tosyali.
References Ayas Z, Barlas EN, Kolonkaya D. Determination of organochlorine pesticide residues in various environments and organisms in Gfksu Delta, Turkey. Aquat Toxicol 1997;39:171 – 81. Barlas NE. Determination of organochlorine pesticide residues in aquatic systems and organisms in Upper Sakarya basin, Turkey. Bull Environ Contam Toxicol 1999;62:278 – 85. Bester K, Beernaert H, Bernreuther A, Harbeck S, Konieczka P, Linsinger TPJ, et al. Intercomparison on measurements of PCBs in pork fat during the Belgian PCB-crisis. Anal Bioanal Chem 2002;374:305 – 13. Boon JP, Lewis WE, Tjoen-A-Choy MR, Allchin CR, Law RJ, de Boer J, et al. Levels of polybrominated diphenyl ether (PBDE) flame retardants in animals representing different trophic levels of the North Sea food web. Environ Sci Technol 2002;36:4025 – 32. Brouwer A, Longnecker MP, Birnbaum LS, Cogliano J, Kostyniak P, Moore J, et al. Characterization of potential endocrine-related health effects at low-dose levels of exposure to PCBs. Environ Health Perspect 1999;107(Suppl. 4):639 – 49. ¨ rn U. Tissue distribution of 2,2 V,4,4 VBurreau S, Broman D, O tetrabromo[C-14]diphenyl ether ([C-14]-PBDE 47) in pike (Esox lucius) after dietary exposure—a time series study using whole body autoradiography. Chemosphere 2000;40:977 – 85. Coelhan M, Barlas H. Levels of some organochlorine contaminants in fishes from Turkey. Fresenius Environ, Bull 1998;7(5A–6A):388 – 95. Cogliano VJ. Assessing the cancer risk from environmental PCBs. Environ Health Perspect 1998;106:317 – 23. ¨ zdemir M, O ¨ zbek H, Bilgili N, Burgaz S. C¸ok I, Bilgili A, O Organochlorine pesticide residues in human breast milk from agricultural regions of Turkey, 1995–1996. Bull Environ Contam Toxicol 1997;59:577 – 82. C ¸ ok I, Gfrqcq E, Satiroglu MH, Demircigil G.C ¸ . Polychlorinated biphenyl (PCB) levels in human milk from Turkish mothers. Bull Environ Contam Toxicol 2003;70:41 – 5. Covaci A, Van de Vijver I, De Coen W, Das K, Bouquegneau JM, Blust R, et al. Determination of organohalogenated contaminants in liver of harbour porpoises stranded on the Belgian North Sea coast. Mar Pollut Bull 2002a;44:1156 – 64. Covaci A, Gheorghe A, Hulea O, Schepens P. Levels of organohalogenated pollutants (PCBs, OCPs and PBDEs) in biota from the Danube Delta, Romania. Organohalog Compd 2002b;59:9 – 12. Covaci A, Gheorghe A, Schepens P. Levels and enantiomeric signatures of a-HCH in an aquatic food chain from the Danube Delta, Romania. Organohalog Compd 2003;62:305 – 8. Covaci A, Gheorghe A, Schepens P. Distribution of organochlorine pesticides and a-HCH enantiomers in pork tissues. Chemosphere 2004;56:757 – 66. Darnerud PO. Toxic effects of brominated flame retardants in man and in wildlife. Environ Int 2003;29:841 – 53. Darneurd PO, Ericksen GS, Johannesson T, Larsen PB, Viluksela M. Polybrominated diphenly ethers: occurrence, dietary exposure, and toxicology. Environ Health Perspect 2001;109:49 – 68. de Boer J, de Boer K, Boon JP. Polybrominated biphenyls and diphenylethers. In: Paasivirta J, editor. The Handbook of Environmental Chemistry, vol. 3. Berlin7 Springer-Verlag; 2000. p. 61 – 95 part K. de Boer J, Wells DE, Nore´n K. BSEF/Quasimeme interlaboratory study on brominated flame retardants. Organohalog Compd 2002;58:197 – 200. Dodder NG, Strandberg B, Hites RA. Concentrations and spatial variations of polybrominated diphenly ethers and several organochlorine com-
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711 pounds in fishes from the Northeastern United States. Environ Sci Technol 2002;36:146 – 51. Falandysz J, Wyrzykowska B, Strandberg L, Puzyn T, Strandberg B, Rappe C. Multivariate analysis of the bioaccumulation of polychlorinated biphenyls (PCBs) in the marine pelagic food web from the southern part of the Baltic Sea, Poland. J Environ Monit 2002;4:929 – 41. Fisk AT, Hobson KA, Norstrom RJ. Influence of chemical and biological factors on trophic transfer of persistent organic pollutants in the Northwater Polynya marine food web. Environ Sci Technol 2001;35: 732 – 8. Fqrst P. Contribution of different pathways to human exposure to PCDDs/ PCDFs. Organohalog Compd 1993;13:1 – 8. Hoekstra PF, O’Hara TM, Karlsson H, Solomon KR, Muir DCG. Enantiomer-specific biomagnification of alpha-hexachlorocyclohexane and selected chiral chlordane-related compounds within an arctic marine food web. Environ Toxicol Chem 2003;22:2482 – 92. Jaward FM, Farrar NJ, Harner T, Sweetman AJ, Jones KC. Passive air sampling of PCBs, PBDEs, and organochlorine pesticides across Europe. Environ Sci Technol 2004;38:34 – 41. Johnson A, Olson N. Analysis and occurrence of polybrominated diphenyl ethers in Washington State freshwater fish. Arch Environ Contam Toxicol 2001;41:339 – 44. Langer P, Kocan A, Tajtakova M, Petrik J, Chovancova J, Drobna B, et al. Possible effects of polychlorinated biphenyls and organochlorinated pesticides on the thyroid after long-term exposure to heavy environmental pollution. J Occup Environ Med 2003;45:526 – 32.
711
Loganathan BG, Kannan K, Watanabe I, Kawano M, Irvine K, Kumar S, et al. Isomer-specific determination and toxic evaluation of polychlorinated biphenlys, polychlorinated/brominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyl ethers, and extractable organic halogen in carp from the Buffalo River, New York. Environ Sci Technol 1995;29:1832 – 8. Moisey J, Fisk AT, Hobson KA, Norstrom RJ. Hexachlorocyclohexane (HCH) isomers and chiral signatures of alpha-HCH in the arctic marine food web of the Northwater Polynya. Environ Sci Technol 2001;35: 1920 – 7. Svobodova` Z, Piacka V, Vykusova` B, Ma`chova` J, Hejtma`nek M, Hrbkova` M, et al. Residues of pollutants in Siluriformes from various localities of the Czech Republic. Acta Vet Brno 1995;64:195 – 208. Voorspoels S, Covaci A, Schepens P. Polybrominated diphenyl ethers in marine species from the Belgian North Sea and the Western Scheldt Estuary: levels, profiles, and distribution. Environ Sci Technol 2003;37:4348 – 57. Wiberg K, Letcher RJ, Sandau CD, Norstrom RJ, Tysklind M, Bidleman TF. The enantioselective bioaccumulation of chiral chlordane and alpha-HCH contaminants in the polar bear food chain. Environ Sci Technol 2000;34:2668 – 74. Wong CS, Hoekstra PF, Karlsson H, Backus SM, Mabury SA, Muir SCG. Enantiomer fractions of chiral organochlorine pesticides and polychlorinated biphenyls in standard and certified reference materials. Chemosphere 2002;49:1339 – 47.
Levels of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in fish species from Kahramanmaras, Turkey ¨ zlem Erdogrula, Adrian Covacib,T, Paul Schepensb O a
Department of Food Science and Technology, Faculty of Agriculture, University of Kahramanmaras Su¨tc¸u¨ Imam, Kahramanmaras, Turkey b Toxicological Center, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium Received 2 November 2004 Available online 7 March 2005
Abstract The levels of organohalogenated contaminants, such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in four fish species (Acanthobrama marmid (kalashpa), Cyprinus carpio (carp), Chondrostoma regium (nose-carp), and Silurus glanis (wels)) from the Sir Dam Lake, Kahramanmaras, Turkey. These species were selected for their characteristic feeding behaviour and their importance to local human fish consumption. DDTs were the predominant organohalogenated contaminants in all species, with the p,pV-DDE contributing to more than 90% to the total DDTs. Other OCPs, such as hexachlorocyclohexane (HCH) isomers, chlordanes and hexachlorobenzene (HCB) were found at much lower levels in all five species. The levels of PCBs and PBDEs (on wet weight basis) were lower than in similar species from European or American freshwater systems. PBDE data were measured for the first time in fish species from Turkish environment. Lipid-based concentrations of OCPs, PCBs and PBDEs were higher in wels than in the other species and this was related to its piscivorous feeding mode and to its higher lipid content. Contrarily, concentrations of pollutants in nose-carp were the lowest, in agreement with its more herbivorous diet. A preferential accumulation in muscle compared to liver was observed for all OCPs, PCBs, and PBDEs in wels and carp, while in nose-carp, a preferential accumulation in liver was observed only for PBDEs, p,pV-DDT and PCBs. Racemic amounts for a-HCH were measured in all investigated muscle and liver samples, except for carp muscle. D 2005 Elsevier Ltd. All rights reserved. Keywords: Fish; Polychlorinated biphenyls; Organochlorine pesticides; Polybrominated diphenyl ethers; Turkey
1. Introduction The production and intensive agricultural or industrial use of persistent organohalogenated pollutants (POPs), such as organochlorine pesticides (OCPs) or polychlorinated biphenyls (PCBs), have led to the widespread contamination of the environment. Polybrominated diphenyl ethers (PBDEs) have come into extensive use as flame retardant additives to plastics, textiles, electronics and paints (de Boer et al., 2000). Due to their persistence, lipid solubility, and
T Corresponding author. Fax: +32 3 820 2722. E-mail address: [email protected] (A. Covaci). 0160-4120/$ - see front matter D 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.envint.2005.01.002
structural similarity to PCBs, PBDEs are emerging as a new class of environmental contaminants (de Boer et al., 2000; Darneurd et al., 2001). Being lipophilic, POPs are characterised by a high bioaccumulation potential in food chains and therefore may pose a serious threat to upper trophic levels of aquatic communities (Fisk et al., 2001; Boon et al., 2002; Falandysz et al., 2002). In biological systems, several of these chemicals are potentially carcinogenic and may cause alternations in endocrine, reproductive and nervous systems (Cogliano, 1998; Brouwer et al., 1999; Darnerud, 2003; Langer et al., 2003). For these reasons, most countries have restricted or banned the use of PCBs and OCPs. However, the environmental persistence of POPs, along with the large
704
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
volume usage of these compounds in the past (for PCBs and OCPs) and in the present (for PBDEs), suggests that they could remain a serious environmental problem for a number of years. Fish is a suitable indicator for the environmental pollution monitoring because they concentrate pollutants in their tissues directly from water, but also through their diet, thus enabling the assessment of transfer of pollutants through the trophic web (Fisk et al., 2001; Boon et al., 2002). Data on the presence and distribution of organohalogenated contaminants in fish and especially edible fish species are therefore important not only from ecological, but also human health perspective. Humans are exposed inadvertently to POPs through numerous sources, of which the consumption of contaminated fish is one of the most important pathways (Fqrst, 1993). In Turkey, OCPs have been used since 1945, with large quantities of these chemicals being used during the 1960s and 1970s. Since 1983, the usage of OCPs has been severely restricted or banned (C ¸ ok et al., 1997). Only few studies have investigated the presence of OCPs in Turkish aquatic environment, where they have been evidenced in relatively high concentrations (Ayas et al., 1997; Coelhan and Barlas, 1998; Barlas, 1999). The principal aim of this study was to investigate the levels of organohalogenated contaminants in several fish species from Sir Dam Lake (Kahramanmaras, Turkey), an artificial lake with great economical importance for the
region. Additionally, the distribution of pollutants, including the a-HCH enantiomers, between muscle and liver was also investigated.
2. Materials and methods 2.1. Study area The Ceyhan river basin is located in the eastern Mediterranean region of Turkey and drains into the Mediterranean Sea in the South (Fig. 1). It covers 20 670 km2 spread over three major provinces (Kahramanmaras, Osmaniye and Adana) and has a potential of up to 590 000 ha of irrigable land. Sir Dam Lake, with a surface of 4750 ha and a maximum capacity of 10 120 hm3, was constructed between 1987 and 1991 and is the 2nd important dam in the Ceyhan river basin. The dam aimed to irrigate approximately 100 000 ha of land, to generate electrical power and to reduce the occurrence of floods. Agricultural production in the region is dominated by cotton (~50%) and wheat (36%), followed by groundnuts, maize, fodder, rice and watermelon. Annual fish production was estimated at approximately 86 ton in 1997. Several potential sources of pollution are present around the lake and they include not only paper, textile, oil and milk industries, but also waste from slaughterhouses or household.
Fig. 1. The map of sampling site showing the Sir Dam Lake (Kahramanmaras, Turkey).
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
705
land) was used for the extraction of target compounds from tissues.
2.2. Sampling A total of 80 individual fishes, representing 4 species Acanthobrama marmid (A) (kalashpa), Cyprinus carpio (C) (carp), Chondrostoma regium (Co) (nose-carp), and Silurus glanis (S) (wels), were obtained from fishermen along the Sir Dam Lake. The first 3 species belong to the Cyprinidae family and are benthopelagic fishes with an omnivorous feeding mode (insect larvae, crustaceans, annelids, plants and molluscs), except for the nose-carp with a more herbivorous diet (phytoplankton and zooplankton). Wels belongs to the Siluridae family and is mainly carnivore with its main diet composed of fish, amphibians, and small aquatic animals. Fishes were caught between January and June 2003. The length of the fish was measured from the front-tip of the mouth to the beginning of the caudal fin (standard length). Information on the length, weight, and age is given in Table 1. Only the excised muscle and liver samples were collected and they were stored at 20 8C until analysis. 2.3. Materials The organochlorine pesticides under investigation were hexachlorobenzene (HCB), p,pV-DDE, p,pV-DDD, o,pV-DDT and p,pV-DDT (expressed as DDTs), a-, h-, g- isomers of hexachlorocyclohexane (expressed as HCHs), oxychlordane (OxC), trans-nonachlor (TN), trans-(TC) and cis-chlordane (CC) (expressed as CHLs). The following polychlorinated biphenyl (PCB) congeners tri (28), tetra (74), penta (99, 101, 105, 118), hexa (128, 138, 153, 156), hepta (170, 180, 183, 187), octa (194 and 199) were targeted. Brominated flame retardants included polybrominated diphenyl ethers (PBDEs) congeners 28, 47, 99, 100, 153, 154 and 183 and brominated biphenyl (BB) 153. All individual standards of OCPs, PCBs and PBBs were obtained from Dr. Ehrenstorfer Laboratories (Augsburg, Germany), while PBDE standards were available from Wellington Laboratories (Guelph, Canada). Acetone, nhexane, dichloromethane and iso-octane were of pesticide grade (Merck, Germany). Anhydrous sodium sulphate and silica gel (Merck) were used after heating overnight at 120 8C. An accelerated Soxhlet extractor B-811 (Buchi, Switzer-
2.4. Methods The methods used for sample preparation and analysis have been previously described and validated (Covaci et al., 2002a, 2004; Voorspoels et al., 2003) and are presented briefly below. 2.5. Sample preparation Approximately 3 g fish tissue was ground with anhydrous sodium sulphate and placed into a hexane-prewashed extraction thimble. Internal standards (10 ng of PCB 46 and PCB 143, 7.5 ng of E-HCH, 2 ng of BB 103 and 0.5 ng of BB 155) were added and the mixture was extracted for 2 h with 75 ml hexane/acetone=3:1 (v/v) with a hot Soxhlet manifold. After concentration to approximately 5 ml, an aliquot (~1/6 of the extract) was used to determine the lipid content by evaporating the solvent at 105 8C for 1 h. The rest of the extract was subjected to clean-up onto a cartridge containing ~8 g silica impregnated with concentrated sulfuric acid (44%). Complete elution of OCPs, PCBs, and PBDEs was done with 15 ml n-hexane followed by 10 ml dichloromethane. The final eluate was concentrated with a rotary-evaporator and further under nitrogen to near dryness. The extract was solubilized in 80 Al iso-octane and analysed for POPs (see below). For the analysis of a-HCH enantiomers, previously obtained extracts were fractionated on a silica SPE cartridge (500 mg, 3 ml, Supelco, Bornem, Belgium). After loading the extract, the 1st fraction, containing all PCBs, p,pV-DDE and p,pV-DDT, was eluted with 4 ml hexane, while the 2nd fraction containing all HCH isomers and p,pV-DDD, was eluted with 3 ml dichloromethane and concentrated to 50 Al. 2.6. Instrumentation Chromatographic conditions have been previously described in detail (Covaci et al., 2002a, 2004; Voorspoels et al., 2003).
Table 1 Biometric data and lipid concentrations in muscle and livers from 4 fish species from Turkey Tissue
Acanthobrama marmid Cyprinus carpio (carp) Chondrostoma regium (nose-carp) Silurus glanis (wels)
N
Lipids (%)
Weight (g)
Standard length (mm)
Age (years)
Mean/median
Range
Mean/median
Range
26–101
13/13
12–17
2.1/2
1–4
400–1834
36/36
25–43
6.3/7
4–8
120/107
52–246
19/18
15–24
4/4
2–6
2520/653
194–31000
55/45
33–151
1.4/1
1–4
Mean/median
Range
Mean/median
24
1.74/1.60
0.69–4.04
43/30
Muscle Liver Muscle Liver
17 8 17 3
0.66/0.34 5.72/5.51 1.63/1.63 7.95/7.39
0.21–2.63 3.31–8.67 0.50–3.56 3.94–12.52
1145/1180
Muscle Liver
22 8
2.22/0.95 3.63/3.03
0.30–11.53 2.11–6.07
Range
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
706
2.6.1. PCBs One microliter extract was injected in pulsed splitless mode into a Hewlett Packard 6890 gas chromatograph (GC) with electron capture detector (A-ECD) equipped with a 50 m0.22 mm0.25 Am, HT-8 capillary column (SGE, Zulte, Belgium). 2.6.2. PBDEs One microliter extract was injected in cold splitless mode into a GC coupled to a HP 5973 mass spectrometer (MS) operated in the electron-capture chemical ionization (ECNI) in SIM mode (monitored ions m/z=79 and 81) and equipped with a 25 m0.22 mm0.25 Am, HT-8 capillary column. The ion source, quadrupole and interface temperatures were 250, 150 and 300 8C, respectively. 2.6.3. OCPs The same system used for PBDEs was employed for the analysis of OCPs, but using other conditions. The ion source, quadrupole and interface temperatures were 150, 150 and 300 8C, respectively. One microliter of the extract was injected in pulsed splitless mode and two specific ions for each pesticide were monitored in pre-defined windows according to their retention times. 2.6.4. Enantioselective analysis The 2nd fraction resulted from silica fractionation was analysed by GC/ECNI-MS using a 30 m0.25 mm0.25 Am Chirasil-Dex column (Chrompack, Middelburg, The Netherlands). A volume of 35 Al of the extract was injected in solvent vent injection mode. Ion source and quadrupole temperatures were 150 8C and 150 8C, respectively. Three ions (255, 253 and 71) were monitored for a-HCH. The enantiomeric ratio (ER) was defined as the ratio of peak area of the first ((+) a-HCH) to the second eluting enantiomer (() a-HCH). The elution order of the two enantiomers was checked with enantioenriched standards (Dr. Ehrenstorfer, Augsburg, Germany). A good reproducibility (RSD b1.5%) for injections of standard solutions allowed the determination with sufficient significance of minor changes in ERs. The enantiomeric fraction (EF) was defined as ER/(ER+1). ER ¼
AðþÞaHCH AðÞaHCH
EF ¼
ER : 1 þ ER
2.7. Quality assurance Multi-level calibration curves were created for the quantification and good linearity (r 2N0.999) was achieved for tested intervals that included the whole concentration range found in samples. The analyte identification was based on their relative retention times (RRT) to the internal standard used for quantification (for ECD) and on retention times, ion chromatograms and intensity ratios of the monitored ions for GC/MS. A deviation of the ion intensity
ratios within 15% of the mean values of the calibration standards was considered acceptable. Peak area ratios (analyte response/internal standard response) were plotted against the concentration ratios (analyte concentration/ internal standard concentration). Method limits of quantification (LOD) for individual OCPs, PCB and PBDE congeners ranged between 0.02 and 0.1 ng/g wet weight (ww). Recoveries for target analytes varied between 75 and 104 (RSD b12%). The method performance was assessed through rigorous internal quality control, which included daily check of calibration curves, regular analysis of procedural blanks and certified materials CRM 349 (PCBs in cod liver oil) and CRM 430 (OCPs in pork fat). The method was tested by participation in an interlaboratory test organised by the Institute for Reference Measurements and Materials (IRMM, Geel, Belgium). Seven PCB congeners (nos. 28, 52, 101, 118, 138, 153 and 180) were determined in nonspiked, medium- and high-level spiked pork fat. The results of the individual PCB congeners deviated less than 10% from the target values (Bester et al., 2002). For PBDEs, the participation to the second interlaboratory test (de Boer et al., 2002) on PBDE (which included fish tissue) showed a variation of less than 10% from mean values obtained from 42 participating laboratories. To evaluate the accuracy of EF measurements for a-HCH enantiomers, a standard reference material (SRM 1945, whale blubber) was analysed. The EF found for the a-HCH enantiomers (0.583F0.004, n=3), compares favourably with the value of 0.574F0.007 (n=5) found by Wong et al. (2002). 2.8. Statistical analysis All statistical analyses were completed with STATISTICA for Windows (StatSoft, Tulsa, OK, USA). Due to relative large dispersion of values, the concentrations of pollutants in fish muscle and liver are summarised using medians together with minimum and maximal values. Values below LOQ were set to zero. The distribution of the organohalogenated compounds was not normal (Shapiro–Wilks test, pN0.05) and therefore non-parametric statistics were employed. The levels of contamination between species were compared using non-parametric Kruskal–Wallis tests. Comparison of profiles and concentrations between liver and muscle was performed by using Wilcoxon non-parametric tests. Finally, all performed correlations were carried out using non-parametric Spearman Rank correlation. The level of significance was set at a=0.05 throughout this study.
3. Results Lipid concentrations in muscle and liver from 4 fish species from Sir Dam Lake are showed in Table 1. Lipid
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
707
Table 2 Concentrations of organohalogenated pollutants (expressed in ng/g wet weight) in muscle of selected fish species from Turkey Acanthobrama marmid (n=24) BDE 28 BDE 47 BDE 99 BDE 100 BDE 153 BDE 154 Sum BDEs Sum PCBs HCB a-HCH h-HCH g-HCH Sum HCHs Oxychlordane Trans-nonachlor Trans-chlordane Cis-chlordane Sum CHLs p,pV-DDE p,pV-DDD p,pV-DDT Sum DDTs
Cyprinus carpio (n=17)
Chondrostoma regium (n=17)
Silurus glanis (n=22)
Range
Median
Range
ND–1.07 ND–0.10 ND–0.12 ND–0.08 ND–0.11 ND–1.5 ND–10.0 0.05–0.34 ND–0.10 0.02–0.19 ND–0.22 0.02–0.33 ND–0.05 ND–0.30 ND–0.20 0.01–0.18 0.02–0.72 7.7–233 0.65–12.1 ND–0.74 8.4–246
ND 0.33 0.03 0.04 0.02 0.03 0.50 3.4 0.19 0.13 0.09 0.16 0.43 ND 0.07 0.06 0.05 0.17 50.2 3.2 0.62 53.8
ND–0.13 0.05–5.3 ND–0.15 ND–0.50 ND–0.28 ND–0.38 0.06–6.7 0.39–42.3 0.05–1.5 0.02–1.1 ND–0.46 ND–1.1 0.13–2.2 ND–0.21 0.03–1.4 0.02–1.1 0.02–0.91 0.07–3.6 20.2–901 1.3–54.3 0.02–4.5 22.1–960
Median
Range
Median
Range
Median
ND 0.54 ND 0.04 0.04 0.03 0.67 3.0 0.16 0.05 0.06 0.05 0.22 ND 0.13 0.12 0.08 0.35 73.5 5.3 0.13 77.4
ND–0.05 0.14–1.2 ND–0.06 0.02–0.11 ND–0.07 ND–0.13 0.18–1.6 ND–12.4 0.08–0.45 0.02–0.13 0.03–0.19 ND–0.55 0.08–0.65 ND–0.09 0.03–0.52 0.04–0.71 0.02–0.34 0.09–1.7 22.1–273 1.9–16.6 ND–0.55 24.1–290
ND 0.13 0.02 ND ND ND 0.15 0.94 0.07 0.03 0.03 0.07 0.21 ND 0.02 0.02 0.01 0.05 13.3 0.82 0.08 14.4
ND–0.16 ND–1.06 ND–0.06 ND–0.06
ND 0.07 ND ND ND ND 0.08 0.39 0.11 0.04 0.04 ND 0.08 ND 0.03 0.02 0.02 0.08 32.3 2.3 0.09 34.8
ND–0.10 0.02–1.3 ND–4.8 0.03–0.41 0.02–0.40 0.02–0.24 ND–0.67 0.04–0.75 ND–0.10 ND–0.87 ND–0.19 ND–0.20 ND–1.4 4.0–156 0.35–13.0 ND–1.23 4.5–170
percentages in muscle are similar for kalashpa, nose-carp, and wels, but are higher ( pb0.01) than lipid percentages in carp and barbel. Lipid percentages in the liver of carp, nosecarp and wels are higher than the corresponding lipid percentages in muscle. Liver lipid percentages in wels are significantly lower ( pb0.05) than in carp and nose-carp. Concentrations of organohalogenated pollutants, expressed in ng/g ww in muscle of selected fish species from Sir Dam Lake are showed in Table 2 and concentrations of organohalogenated pollutants, expressed in ng/g lipid weight (lw) in muscle and liver in Table 3. All muscle and liver samples contained HCB, a-HCH, p,pV-DDD and p,pV-DDE, while the other organochlorine pesticides were detected with a lesser frequency. DDTs were the prevalent organohalogenated contaminants found in the investigated fish species from Sir Dam Lake. The median levels of sum DDTs in kalashpa, carp,
nose-carp and wels muscle samples were 77.4, 14.4, 34.8 and 53.8 ng/g ww, respectively (Table 2). The dominant metabolite was p,pV-DDE, which constituted 93–95% of the sum DDTs for each species, followed by p,pV-DDD (5–7%) and p,pV-DDT (b0.5%). The median concentrations of p,pVDDE in kalashpa, carp, nose-carp and wels muscle samples were 73.5, 13.3, 32.3, 50.2 ng/g ww, respectively, while the median levels of p,pV-DDE in liver of carp, nose-carp and wells were 193, 317, 119 ng/g ww, respectively. The a-HCH isomer was found in 100% of fish samples, while the h- and g-HCH isomers were found in 98 and 66% samples, respectively. The median levels of sum HCHs in muscle of kalashpa, carp, nose-carp and wels were 0.22, 0.21, 0.08 and 0.43 ng/g ww, respectively (Table 2). The three HCH isomers were present in different proportions in the fish species, with slightly higher contribution of g-HCH in carp.
Table 3 Concentrations of organohalogenated pollutants (expressed in ng/g lw) in muscle and liver of selected fish species from Turkey (see Sampling for fish species identification) A N Sum HCHs Sum CHLs Sum DDTs Sum PCBs Sum PBDEs
Median Range Median Range Median Range Median Range Median Range
C muscle
C liver
Co muscle
Co liver
S muscle
S liver
24
17
8
17
3
22
8
16 6–41 22 8–41 4993 2214–7170 271 76–400 34 11–110
30 9–159 16 2–74 3866 1321–10023 165 2–486 34 7–597
23 11–108 10 6–23 3327 550–5297 73 14–243 39 ND–68
8 4–20 6 3–28 3210 1687–9520 42 2–387 9 ND–62
11 9–24 15 8–41 2753 2220–4667 144 50–200 44 17–163
31 10–144 20 11–70 5800 2470–18171 312 70–887 39 10–183
35 1–55 9 5–17 3338 2260–4673 123 28–289 34 6–52
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
708 45
kalashpa 40
carp-M 35
carp-L 30
%PCB
nose-carp-M 25
nose-carp-L 20
wels-M
15
wels-L
10 5 0 28
74
101
99
118
153
105
138
187
183
128
156
180
199
170
194
PCB congener Fig. 2. Mean PCB percentage in muscle (M) and liver (L) from investigated fish species from Sir Dam Lake, Turkey. For species identification, see Sampling.
The median concentrations of sum CHLs in the 4 fish species were at similar levels with HCH isomers (Table 2), with the highest values found for kalashpa and wels (0.35 and 0.17 ng/g ww, respectively). The highest contributor to the sum CHLs was trans-nonachlor followed by transchlordane. Oxychlordane had a higher detection frequency in wells, but never higher than 40%. PCB concentrations were also determined in the selected fish muscle and liver samples. The median levels of sum PCBs in kalaspha, carp, nose-carp and wels muscle samples were 3, 0.94, 0.39, 3.4 ng/g ww, respectively (Table 2). For all species, the PCB profile was dominated by the tri- to penta-CB isomers, which constituted between 53% and 90% of the total PCBs (Fig. 2). The most persistent PCB congeners (nos. 138, 153 and 180) were present in higher percentage in kalashpa, but with a much lower contribution to sum PCBs than reported for similar species from other worldwide locations (Svobodova` et al., 1995; Covaci et al., 2002b). PBDEs were detected in all muscle and liver samples, except few samples of carp liver and nose-carp muscle. The PBDE levels were lower than the PCB levels, but they were
Table 4 Distribution of organohalogenated contaminants between liver and muscle of carp, nose-carp and wels, expressed as c liver/(c muscle+c liver), concentration expressed per lipid weight
1000.0
Concentration (ng/g ww)
at the same level or higher than some OCPs, such as HCB, HCHs and CHLs. The median levels of sum BDEs in kalashpa, carp, nose-carp and wels muscle samples were 0.67, 0.15, 0.08 and 0.50 ng/g ww, respectively. BDE 47 was the dominant congener in all muscle and liver samples. PBB 153 was not found in any samples, indicating the very limited usage of Firemaster technical mixtures of PBBs in Turkey. Concentrations of pollutants (in ng/g ww) were significantly related to the lipid percent (Fig. 3) and the best correlations were obtained for p,pV-DDE and p,pV-DDD (R 2=0.793 and 0.780, pb0.05, respectively). The distribution of organohalogenated contaminants between liver and muscle was assessed through the calculation of the accumulation ratio c liver/(c muscle+c liver), where concentrations were expressed in ng/g lw. Values lower than 0.50 indicate a preferential accumulation in the muscle. A preferential accumulation in muscle compared to liver was observed for all OCPs, PBDEs and PCBs for wels and carp, while for nose-carp, a preferential accumulation in liver was observed for only PBDEs, p,pV-DDT and PCBs (Table 4).
100.0 p,p'-DDE
10.0
PBDEs
Cyprinus carpio (carp) (n=8)
Chondrostoma regium (nose-carp) (n=3)
Silurus glanis (wels) (n=8)
0.34F0.13 0.33F0.12 0.38F0.11 0.46F0.10 0.48F0.09 0.45F0.29 0.25F0.11 0.38F0.22
0.55F0.14 0.46F0.16 0.49F0.07 0.48F0.13 0.50F0.09 0.62F0.26 0.57F0.11 0.58F0.22
0.39F0.06 0.36F0.09 0.41F0.07 0.36F0.06 0.40F0.08 0.33F0.12 0.24F0.08 0.33F0.14
HCB
1.0
p,p'-DDD PCBs
0.1 0.0 0.1
1.0
10.0
100.0
% Lipid Fig. 3. Relationships between concentrations of pollutants (ng/g ww) and lipid percentage.
a-HCH h-HCH HCB p,pV-DDE p,pV-DDD p,pV-DDT PCBs PBDEs
Values lower than 0.50 indicate a preferential accumulation in the muscle.
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711 Table 5 Mean and standard deviations of enantiomeric ratios (ERs) and enantiomeric fractions (EFs) of a-HCH in liver and muscle of Acanthobrama marmid (A), Cyprinus carpio (C), Chondrostoma regium (Co), and Silurus glanis (S) A muscle (n=3) Co muscle (n=2) C muscle (n=2) S muscle (n=3) Co liver (n=2) C liver (n=2) S liver (n=3)
ERFS.D.
EFFS.D.
1.022F0.033 0.971F0.071 0.930F0.043 0.982F0.023 1.013F1.013 1.004F0.012 1.008F0.013
0.505F0.008 0.492F0.018 0.482F0.012 0.496F0.006 0.503F0.012 0.501F0.003 0.502F0.003
Racemic enantiomeric fractions for a-HCH were determined in muscle of kalashpa, nose-carp and wels and in liver of carp, nose-carp and wels (Table 5). Non-racemic values could be determined only in muscle of carp.
4. Discussion Due to their known persistency, liposolubility and bioaccumulation in species at higher trophic levels, organohalogenated contaminants, such as OCPs, PCBs and PBDEs, are necessary to be monitored in the environment and with a special attention for animal species which may be part of the human food. Several fish species representative for the human fish consumption in the Kahramanmaras region were selected for investigation of their contamination with POPs. Relatively low concentrations of organohalogenated pollutants were found in the fish samples with the most abundant pollutant in all fish samples being p, pV-DDE, the main metabolite of p,pV-DDT. The concentrations of DDTs in carp samples were in the same range with those reported by Ayas et al. (1997) for carp from the Gfksu Delta, but were lower than those reported by Barlas (1999) for the Upper Sakarya basin. Due to (bio)transformation kinetics, the p, pV-DDE/ p, pV-DDT ratio increases with time after the exposure to p, pV-DDT has ceased or was diminished through restricting regulations. In our study, the mean p, pV-DDE/ p, pV-DDT ratio in the muscle of the five investigated species ranged from 100 to 650 and can be correlated with past exposure to DDT (high p, pV-DDE content) and with low present exposure to DDT (low p,pVDDT levels). Another metabolite of DDT, p,pV-DDD, was also found, but in lower amounts than p,pV-DDE. The levels of a-, h- and g-HCH isomers in the fish species from Sir Dam Lake are lower than values found by Barlas (1999) in the Sakarya basin suggesting different pollutant factors in the two aquatic environments. None of the three HCH isomers was predominant in the investigated fish species. Although the usage of HCB has been severely restricted in Turkey since 1959, all analysed fish samples contained low, but detectable residues of HCB. This low level of
709
contamination can have its origin in the various industrial processes from which HCB can be emitted as a by-product in high-temperature processes. HCB may also be present as impurity in other chlorinated pesticides and, most probably, it is related to the long-range air transport from more contaminated areas of Europe (Jaward et al., 2004). PCBs were used as coolant/dielectrics in transformers, capacitors and other electrical equipment in several countries, including Turkey. Between 1970 and 1982, a combination of transformer oil and lindane (g-HCH) (48+4%) was widely used as pesticide in Turkey (C ¸ ok et al., 2003). The usage of PCBs in closed systems was restricted in Turkey since 1983, while their use in open applications was banned only in 1996 (C ¸ ok et al., 2003). However, the exposure to PCBs can still occur through the disposal of PCB-containing equipment and through the refilling and repairing of closed applications, for which there are no strict regulations (C ¸ ok et al., 2003). The contamination degree with PCBs of the fish samples from the Sir Dam Lake is lower or similar to PCB levels found in other countries. Mean PCB concentrations found by Svobodova` et al. (1995) in carp and wels muscle from Czech Republic were 3 and 17 ng/g ww. Carp and wels from the Danube Delta (Covaci et al., 2002b) contained PCB levels ranging from 3.5 to 18 ng/g ww and from 0.5 to 2.0 ng/g ww, respectively. The PCB levels in the fish species from Sir Dam Lake are also below the tolerance limits for human consumption set for freshwater fish from European countries (1.4 Ag/g ww in Germany). The distribution of PCB congeners in the fish species from Sir Dam Lake (Fig. 2) show an exclusive contamination with low chlorinated PCB congeners (mainly composed of triand tetra-CB congeners), which together with the low PCB concentrations measured in fish suggest a diffuse contamination through the water column in which these congeners have a higher solubility. The PBDE levels, which were measured for the first time in fish species from Turkish aquatic systems, had a maximum value of 6.7 ng/g ww found in a wels sample and were low compared to values found in freshwater fish from USA or Europe. Johnson and Olson (2001) found that total PBDE concentrations ranged from 1.4 to 1250 ng/g ww found in a whitefish collected in an urbanised area of the Spokane River, with most of the data being in the 20– 300 ng/g ww range. Dodder et al. (2002) reported levels ranging from 6.9 to 18 ng/g ww for various fish species, such as smelt, blue gills, crappie from locations with low PBDE contamination and higher levels (up to 65 ng/g ww) in carp fish collected from a near PBDE manufacturing facility. Loganathan et al. (1995) found carp in the Buffalo River to have levels ranging from 13 to 23 ng/g ww for total PBDEs. BDE 47 was clearly the predominant BDE congener in the fish samples, in accordance with its previously reported selective bioaccumulation (de Boer et al., 2000). Despite the present low concentrations of PBDE in fish, the vicinity of textile industry close to the Sir Dam
710
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711
Lake may constitute a potential source of PBDEs and therefore, concentrations of PBDEs in fish may increase in time. For all compounds, lipid-based concentrations (Table 3) were higher in wels than in other species, in accordance with its feeding mode. Contrarily, concentrations of pollutants in nose-carp (Table 3) were the lowest, which agrees with its more herbivorous feeding mode. Being significantly correlated, the lipid percentage is a good predictor for the concentrations of POPs expressed per wet weight (Fig. 3). The best correlations were obtained for p,pV-DDE and p,pVDDD (R 2=0.793 and 0.780, pb0.05, respectively), which are the major organohalogenated contaminants in the Sir Dam Lake. Interestingly, similar slopes for the equation lg(conc. ng/g ww)=f(lg lipid%) were obtained for p,pV-DDE and p,pV-DDD (1.142 and 1.121, respectively), suggesting a similar rate of bioaccumulation. PCBs and PBDEs had the smallest correlation coefficients (R 2=0.355 and 0.331, pb0.05, respectively) suggesting that the high variation in concentrations is due to non-uniformly distributed sources. For carp and wels, residues of all pollutants were detected at higher levels in muscle than in liver (Table 4). Svobodova` et al. (1995) has also observed higher concentrations of DDT and its metabolites in muscle of wels compared to liver (expressed per lw). Contrarily, nose-carp showed a preferential accumulation of pollutants in the liver (Table 4). Burreau et al. (2000) have observed that BDE 47 accumulated in lipid rich tissues in pike (lean fish) and this includes liver (b10%) and perivisceral adipose tissue. With exception of sole, Voorspoels et al. (2003) have also observed a preferential accumulation of PBDE congeners in liver (containing up to 50% lipids) of marine lean fish, such as plaice, bib and whiting. EF values of a-HCH in muscle of fish species from the Turkish environment were racemic for kalashpa, nose-carp, and wels and non-racemic for carp (Table 5), suggesting species-dependent stereospecific bioprocesses. Similar trends were observed for EFs of a-HCH isomers in muscle of carp and wels samples from the Danube Delta (Covaci et al., 2003), for which EF values were 0.465 (n=2) and 0.489 (n=6), respectively. Racemic amounts of a-HCH have also been measured in trout muscle from Lake Michigan (Wong et al., 2002) and whole cod from the Baltic Sea (Wiberg et al., 2000), Northwater Polynya (Moisey et al., 2001) or Arctic (Hoekstra et al., 2003), where it was also the most predominant HCH isomer. Interestingly, EFs measured in all liver samples from nosecarp, carp and wels were racemic, observation which is in accordance with racemic amounts of a-HCH measured in cod liver oil (Wong et al., 2002).
Acknowledgements The Scientific and Technical Research Council of Turkey (TUBITAK) supported this study (NATO B-2). All of the
fish samples were obtained through the assistance of Orhan Bqlbql (Ministry of Agriculture and Rural Affairs of Kahramanmaras, Turkey) and were prepared by Cengiz Tosyali.
References Ayas Z, Barlas EN, Kolonkaya D. Determination of organochlorine pesticide residues in various environments and organisms in Gfksu Delta, Turkey. Aquat Toxicol 1997;39:171 – 81. Barlas NE. Determination of organochlorine pesticide residues in aquatic systems and organisms in Upper Sakarya basin, Turkey. Bull Environ Contam Toxicol 1999;62:278 – 85. Bester K, Beernaert H, Bernreuther A, Harbeck S, Konieczka P, Linsinger TPJ, et al. Intercomparison on measurements of PCBs in pork fat during the Belgian PCB-crisis. Anal Bioanal Chem 2002;374:305 – 13. Boon JP, Lewis WE, Tjoen-A-Choy MR, Allchin CR, Law RJ, de Boer J, et al. Levels of polybrominated diphenyl ether (PBDE) flame retardants in animals representing different trophic levels of the North Sea food web. Environ Sci Technol 2002;36:4025 – 32. Brouwer A, Longnecker MP, Birnbaum LS, Cogliano J, Kostyniak P, Moore J, et al. Characterization of potential endocrine-related health effects at low-dose levels of exposure to PCBs. Environ Health Perspect 1999;107(Suppl. 4):639 – 49. ¨ rn U. Tissue distribution of 2,2 V,4,4 VBurreau S, Broman D, O tetrabromo[C-14]diphenyl ether ([C-14]-PBDE 47) in pike (Esox lucius) after dietary exposure—a time series study using whole body autoradiography. Chemosphere 2000;40:977 – 85. Coelhan M, Barlas H. Levels of some organochlorine contaminants in fishes from Turkey. Fresenius Environ, Bull 1998;7(5A–6A):388 – 95. Cogliano VJ. Assessing the cancer risk from environmental PCBs. Environ Health Perspect 1998;106:317 – 23. ¨ zdemir M, O ¨ zbek H, Bilgili N, Burgaz S. C¸ok I, Bilgili A, O Organochlorine pesticide residues in human breast milk from agricultural regions of Turkey, 1995–1996. Bull Environ Contam Toxicol 1997;59:577 – 82. C ¸ ok I, Gfrqcq E, Satiroglu MH, Demircigil G.C ¸ . Polychlorinated biphenyl (PCB) levels in human milk from Turkish mothers. Bull Environ Contam Toxicol 2003;70:41 – 5. Covaci A, Van de Vijver I, De Coen W, Das K, Bouquegneau JM, Blust R, et al. Determination of organohalogenated contaminants in liver of harbour porpoises stranded on the Belgian North Sea coast. Mar Pollut Bull 2002a;44:1156 – 64. Covaci A, Gheorghe A, Hulea O, Schepens P. Levels of organohalogenated pollutants (PCBs, OCPs and PBDEs) in biota from the Danube Delta, Romania. Organohalog Compd 2002b;59:9 – 12. Covaci A, Gheorghe A, Schepens P. Levels and enantiomeric signatures of a-HCH in an aquatic food chain from the Danube Delta, Romania. Organohalog Compd 2003;62:305 – 8. Covaci A, Gheorghe A, Schepens P. Distribution of organochlorine pesticides and a-HCH enantiomers in pork tissues. Chemosphere 2004;56:757 – 66. Darnerud PO. Toxic effects of brominated flame retardants in man and in wildlife. Environ Int 2003;29:841 – 53. Darneurd PO, Ericksen GS, Johannesson T, Larsen PB, Viluksela M. Polybrominated diphenly ethers: occurrence, dietary exposure, and toxicology. Environ Health Perspect 2001;109:49 – 68. de Boer J, de Boer K, Boon JP. Polybrominated biphenyls and diphenylethers. In: Paasivirta J, editor. The Handbook of Environmental Chemistry, vol. 3. Berlin7 Springer-Verlag; 2000. p. 61 – 95 part K. de Boer J, Wells DE, Nore´n K. BSEF/Quasimeme interlaboratory study on brominated flame retardants. Organohalog Compd 2002;58:197 – 200. Dodder NG, Strandberg B, Hites RA. Concentrations and spatial variations of polybrominated diphenly ethers and several organochlorine com-
O¨. Erdogrul et al. / Environment International 31 (2005) 703–711 pounds in fishes from the Northeastern United States. Environ Sci Technol 2002;36:146 – 51. Falandysz J, Wyrzykowska B, Strandberg L, Puzyn T, Strandberg B, Rappe C. Multivariate analysis of the bioaccumulation of polychlorinated biphenyls (PCBs) in the marine pelagic food web from the southern part of the Baltic Sea, Poland. J Environ Monit 2002;4:929 – 41. Fisk AT, Hobson KA, Norstrom RJ. Influence of chemical and biological factors on trophic transfer of persistent organic pollutants in the Northwater Polynya marine food web. Environ Sci Technol 2001;35: 732 – 8. Fqrst P. Contribution of different pathways to human exposure to PCDDs/ PCDFs. Organohalog Compd 1993;13:1 – 8. Hoekstra PF, O’Hara TM, Karlsson H, Solomon KR, Muir DCG. Enantiomer-specific biomagnification of alpha-hexachlorocyclohexane and selected chiral chlordane-related compounds within an arctic marine food web. Environ Toxicol Chem 2003;22:2482 – 92. Jaward FM, Farrar NJ, Harner T, Sweetman AJ, Jones KC. Passive air sampling of PCBs, PBDEs, and organochlorine pesticides across Europe. Environ Sci Technol 2004;38:34 – 41. Johnson A, Olson N. Analysis and occurrence of polybrominated diphenyl ethers in Washington State freshwater fish. Arch Environ Contam Toxicol 2001;41:339 – 44. Langer P, Kocan A, Tajtakova M, Petrik J, Chovancova J, Drobna B, et al. Possible effects of polychlorinated biphenyls and organochlorinated pesticides on the thyroid after long-term exposure to heavy environmental pollution. J Occup Environ Med 2003;45:526 – 32.
711
Loganathan BG, Kannan K, Watanabe I, Kawano M, Irvine K, Kumar S, et al. Isomer-specific determination and toxic evaluation of polychlorinated biphenlys, polychlorinated/brominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyl ethers, and extractable organic halogen in carp from the Buffalo River, New York. Environ Sci Technol 1995;29:1832 – 8. Moisey J, Fisk AT, Hobson KA, Norstrom RJ. Hexachlorocyclohexane (HCH) isomers and chiral signatures of alpha-HCH in the arctic marine food web of the Northwater Polynya. Environ Sci Technol 2001;35: 1920 – 7. Svobodova` Z, Piacka V, Vykusova` B, Ma`chova` J, Hejtma`nek M, Hrbkova` M, et al. Residues of pollutants in Siluriformes from various localities of the Czech Republic. Acta Vet Brno 1995;64:195 – 208. Voorspoels S, Covaci A, Schepens P. Polybrominated diphenyl ethers in marine species from the Belgian North Sea and the Western Scheldt Estuary: levels, profiles, and distribution. Environ Sci Technol 2003;37:4348 – 57. Wiberg K, Letcher RJ, Sandau CD, Norstrom RJ, Tysklind M, Bidleman TF. The enantioselective bioaccumulation of chiral chlordane and alpha-HCH contaminants in the polar bear food chain. Environ Sci Technol 2000;34:2668 – 74. Wong CS, Hoekstra PF, Karlsson H, Backus SM, Mabury SA, Muir SCG. Enantiomer fractions of chiral organochlorine pesticides and polychlorinated biphenyls in standard and certified reference materials. Chemosphere 2002;49:1339 – 47.