Organochlorine pesticides in two fish species from the southern Caspian Sea

Organochlorine pesticides in two fish species from the southern Caspian Sea

Marine Pollution Bulletin 133 (2018) 289–293 Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/...

654KB Sizes 0 Downloads 58 Views

Marine Pollution Bulletin 133 (2018) 289–293

Contents lists available at ScienceDirect

Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul

Baseline

Organochlorine pesticides in two fish species from the southern Caspian Sea a,⁎

b

Parisa Nejatkhah Manavi , Eftekhar Shirvani Mahdavi , Asit Mazumder a b c

T

c

Dept. of Marine Biology, Faculty of Marine Science and Technology, Islamic Azad University, Tehran North Branch, Iran Dept. of Marine Environment, Faculty of Marine Science and Technology, Islamic Azad University, Tehran North Branch, Iran Dept. of Biology, University of Victoria, Canada

A R T I C LE I N FO

A B S T R A C T

Keywords: Organochlorine Liza aurata Rutilus frisii kutum Caspian Sea

In the present research, we aimed to investigate organochlorine toxins accumulated in both Rutilus frisii kutum and Liza aurata captured at the southern Caspian Sea. At six sampling stations, organochlorine toxins were measured in fish tissues by the gas chromatography–electron capture detector (GC-ECD) method. Total organochlorine toxins ranged from 2.102 ppb to 9.033 ppb in L. aurata at the study area. The highest content of total organochlorine toxins was obtained at station 5, whereas the lowest content was achieved at station 4. In L. aurata, lindane showed the highest level among the measured components (1.642 ppb), whereas αlindane showed the highest mean level of the measured components (0.57 ppb). In this investigation, the total amount of organochlorine compounds in R. frisii kutum was more than that in L. aurata, but these compounds indicated no significant difference between the two types of fishes (p > 0.05). Moreover, the measured components in both types of fishes were lesser than the allowable limit.

Southern Caspian Sea is regarded as an important center for agriculture, and because of different dense cultures, the use of agricultural pesticides and fungicides in farms is very high. After sometime of application, these toxins are often discharged into rivers through soil washing induced by rain in farms, leak of agricultural wastes, and wind blows, and these lead to marine pollution (Ballschmiter et al., 1983). Considering the life cycle of commercial fishes such as whitefish, Mugil, bleak, and carp in the coasts, these toxins are accumulated in fish tissues. Hence, damages of these toxins to human health through contaminated fish consumption are not lesser than their direct damages on the aqueous ecosystem and environment. Therefore, the focus of the harmful effects induced by overconsumption of these toxins is primarily on humans who are affected by various diseases every day (Francour et al., 1994; Gerber et al., 2016). Among all man-made contaminants, the main concern is permanent organic pollutants (POPs). POPs are carbon-based compounds with a mixture of industrial chemicals such as polychlorinated biphenyls (PCB), pesticides, and by-products of combustion such as dioxins. Risks of these pollutants are pertained to their resistance against photolysis, biodegradation and chemical decomposition, high lipophilicity, and high durability for a long time in the environment. Owing to these properties, POPs can bioaccumulate in the lipid tissues of living organisms and consequently increase along the food chain. By this point, these pollutants can have a harsh effect on the health of ecosystem, wildlife, and human beings (Pinet, 2006).



Corresponding author. E-mail address: [email protected] (P. Nejatkhah Manavi).

https://doi.org/10.1016/j.marpolbul.2018.05.056 Received 7 March 2018; Received in revised form 14 May 2018; Accepted 26 May 2018 0025-326X/ © 2018 Published by Elsevier Ltd.

Fish and fishery products form < 10% of our food regimes, but they are the major ways through which these pollutants enter the human body. High consumption of fish in food regimes would result in increased absorption of these compounds. According to previous studies, there is a high correlation between the concentration of chlorine organic pollutants in the blood, milk, and human tissues with the consumption of contaminated fish (Judd et al., 2004). Fish is concerned as a proper indicator for the assessment of pollution in aqueous systems, as they receive the pollutants both directly through water and indirectly through food, thereby resulting in accumulation of toxins in their tissues. Hence, fish is suitable for the examination of pollutant transfer and biomagnification process through food webs (Zhou et al., 2007). In other words, fish is used as an indicator for monitoring water quality, as they directly receive the pollutants from surrounding environment and food, thereby resulting in accumulation of toxins in their tissues. Fishes have poor metabolization of organic organochlorine compounds, thus reflecting the pollution level of their environment (Pastor et al., 1996). Distribution and accumulation of these pollutants in fish tissues indicate the pollution level in sediments and its aqueous environment. The aim of this trail was to determine organochlorine levels in Mugil and whitefish captured from the southern Caspian Sea. In this research, organochlorine pollutants were investigated in L. aurata (10 fish in each site) and R. frisii kutum (10 fish in each site) in

Marine Pollution Bulletin 133 (2018) 289–293

P. Nejatkhah Manavi et al.

Fig. 1. Locations of sampling sites at the coastline of the southern Caspian Sea.

in Mugil ranged from 2.102 ppb to 9.033 ppb. Generally, the highest level of organochlorine was measured at station 4, while the lowest level was observed at station 2 (Fig. 3). In R. frisii kutum, the maximum level of β-lindane was 0.398 ± 0.105 ppb at station 5, whereas those of the other components were at station 1 (Fig. 4). Furthermore, endrin ketone, endrin, endosulfan, metoxy chlor, and heptachlor were not measurable at any station. In this fish, α-lindane showed the highest mean level among the measured components (0.57 ppb). The total level of organochlorine toxins was the highest at station 5 (2.71 ppb) and the lowest at station 4 (1.40 ppb) (Fig. 5). In the case of DDT isomers, it could be noted that DDT was converted into DDE during decomposition under aerobic conditions by microorganisms, whereas under anaerobic conditions, DDD was the main product (Aguilar, 1984). Therefore, aerobic condition of the surrounding environment can be a reason for the observed high level of DDE. DDE is the most important isomer of DDT decomposition, and it bioaccumulates at high levels. In living and nonliving components, DDE is regarded as the most stable isomer with high half-life (Connell et al., 1999; Walker, 2001; Andersen et al., 2001). Moreover, the high level of this compound can be attributed to its direct application along the coasts. In L. aurata, the amount of aldrine was more than that of dieldrin, whereas it was vice versa in R. frisii kutum. Generally, aldrine is readily transformed into dieldrin, which is more toxic than the former form. Generally, bioaccumulation and biomagnification processes have a key role in the content of toxins in the body tissues of the aquatic organisms placed in upper trophic levels of a food chain. Biomagnification is remarkably important in the accumulation of organic pollutants, particularly high hydrophobic pollutants. The process is affected by various biotic factors including feeding habit and habitat of the organism, its feeding condition, its fat content in the body tissue, age, gender, and season of sampling or spawning as well as nonbiotic factors such as chlorine grade of the pollutant, their hydrophobicity coefficient, water solubility degree, ionization degree, and toxin

east, west, and central parts of the southern Caspian Sea (Fig. 1). Fish samples were captured from six stations using a beach seine net in winter 2018 and then transported to the laboratory in ice boxes. Approximately 6 g of tissue was cut and put in a test tube. After weighing the tube, 8 ml of hexan solvent (32%) followed by acetone solvent (a ratio of 1:1) was added. Tubes were covered by aluminum and shaken well on a shaker for 5 min to mix the solvents with the sample. Afterwards, samples were placed in an ultrasonic device for 25 h to completely remove the organic matter and obtain a homogenate solution. Then the supernatant was separated with a syringe and simultaneously injected with helium gas into a gas chromatography device equipped by an electron capture detector (MOOPAM, 1999). Accuracy of the measurements was controlled by a standard reference for marine fish (NO. IAEA-406), and 1000 ppm of a standard solution with a mixture of chlorine toxin prepared by Dr. Ehrenstorfer Company was applied for calibration. Results were classified in an online program of Microsoft database. The obtained peaks were then studied, and data were standardized and calibrated. The type and level of toxins in fish tissue at different stations were measured and reported in ppb. Statistical analysis was performed using SPSS software. Data normality was analyzed by the Kolmogorov–Smirnov test. Moreover, comparison of fish pollution among different stations was done by oneway analysis of variance and Duncan's test when data showed normality. The t-test was applied to compare the pollution level between the two species. The organochlorine toxin levels measured at each station in both R. frisii kutum and L. aurata are presented in Tables 1 and 2. According to the obtained results, the highest amount of DDT, DDD, DDE, aldrine, endrin aldehyde, endrin, dieldrin, lindane, α-lindane, β-lindane, endosulfan were detected at stations 4, 4, 4, 1, 4, 4, 4, 5, 5, 6, and 6, respectively. Moreover, endrin ketone, metoxychlor, and heptachlor were not at detectable levels at any station. Lindane had the highest mean level measured in L. aurata (1.642 ppb) (Fig. 2). The total level of organochlorine toxins measured 290

Marine Pollution Bulletin 133 (2018) 289–293

P. Nejatkhah Manavi et al.

Table 1 Mean ± standard deviation of organochlorine pesticide concentrations (ppb) in L. aurata. Compounds

DDT DDD DDE Aldrine Endrin aldhyde Endrin ketone Endrin Dieldrin Lindane α-Lindane β-Lindane Endosulfan Metoxychlor Heptachlor

Sampling sites 1

2

3

4

5

6

0.095 0.150 + 0.085 0.225 + 0.021 0.370 + 0.042 0.105 + 0.021 ND 0.590 + 0.035 0.360 + 0.099 0.963 + 0.700 ND 0.073 + 0.021 0.160 + 0.035 ND ND

0.170 + 0.057 ND 0.095 + 0.021 0.287 + 0.095 0.133 + 0.084 ND 0.500 + 0.148 0.227 + 0.057 0.427 + 0.256 ND 0.030 + 0.034 0.233 + 0.045 ND ND

0.345 + 0.021 0.085 + 0.021 0.173 + 0.051 0.300 + 0.135 0.085 + 0.035 ND 0.407 + 0.156 0.163 + 0.070 0.830 + 0.157 0.137 + 0.050 0.150 + 0.089 0.280 + 0.030 ND ND

0.643 + 0.131 0.740 + 0.175 0.913 + 0.325 0.233 + 0.032 0.220 + 0.036 ND 0.713 + 0.110 0.273 + 0.104 4.870 + 0.411 ND 0.127 + 0.090 0.300 + 0.035 ND ND

0.230 + 0.020 0.247 + 0.076 0.263 + 0.076 0.103 + 0.040 0.250 + 0.028 ND 0.557 + 0.085 0.163 + 0.042 1.060 + 0.210 0.167 + 0.060 0.087 + 0.025 0.257 + 0.068 ND ND

0.107 + 0.015 0.147 + 0.074 0.140 + 0.069 0.157 + 0.081 ND ND 0.397 + 0.237 0.163 + 0.050 1.703 + 0.371 0.140 + 0.072 0.313 + 0.116 0.350 + 0.061 ND ND

Table 2 Mean ± standard deviation of organochlorine pesticide concentrations (ppb) in R. frisii kutum. Compounds

Sampling sites 1

DDT D.D.D D.D.E. Aldrine Endrin aldehyde Endrin ketone Endrin Dieldrin (γ-HCH)lindane Alpha-lindane Beta-lindane Endosulfan Metoxychlor Heptachlor

0.185 0.135 0.284 0.549 0.552 ND ND 0.257 0.120 ND 0.211 ND ND ND

2 ± ± ± ± ±

0.025 0.040 0.115 0.177 0.436

± 0.077

± 0.022

0.097 0.103 0.246 0.227 0.474 ND ND 0.197 0.323 ND 0.220 ND ND ND

3 ± ± ± ± ±

0.040 0.059 0.160 0.064 0.170

± 0.113

± 0.047

4

0.096 0.084 0.184 0.255 0.582 ND ND 0.161 0.070 0.784 0.219 ND ND ND

± ± ± ± ±

0.036 0.041 0.044 0.121 0.210

± 0.078

0.097 0.099 0.143 0.233 0.358 ND ND 0.189 ND ND 0.283 ND ND ND

5 ± ± ± ± ±

0.016 0.052 0.048 0.076 0.066

± 0.100

± 0.032

0.044 0.057 0.130 0.084 0.418 ND ND 0.109 1.020 0.444 0.398 ND ND ND

6 ± ± ± ± ±

0.013 0.037 0.066 0.014 0.190

± 0.071 ± 0.176 ± 0.105

0.079 0.098 0.123 0.158 0.268 ND ND 0.188 0.246 0.481 0.337 ND ND ND

± ± ± ± ±

0.007 0.036 0.053 0.099 0.319

± 0.068

± 0.009

Fig. 2. Mean ± standard deviation of individual organochlorine pesticide concentrations (ppb) in L. aurata.

the aquatic environment. Therefore, as feeding habit of R. frisii kutum is related to the sediment and sea floor, this fish showed more concentration of these toxins in its body. According to Environmental Preservation Agency of America (EPA, 1992), organochlorine compounds such as γ-BHC, DDD, DDT, δ-BHC, αBHC, heptachlor, DDE, aldrin, heptachlor epoxide, and dieldrin in the present investigation are classified as group B2 and probably considered as carcinogenic agents for humans (EPA, 2004). By contrast, βendosulfan, α-endosulfan, and endosulfan sulfate similar to other compounds of endrin aldehyde and endrin are classified as group D, and this is unlikely that these compounds have carcinogenic effects.

stability. Hence, the most effective factors affecting the absorption of the pollutants in fish tissues are fat content, feeding regime, and species habitat. Fat content is significantly influenced by feeding regime. In this investigation, the total level of organochlorine toxins in R. frisii kutum was more than that of L. aurata but the total concentration of organic chlorine had no significant difference between the two species (p > 0.05) (Fig. 6). In terms of habitat, it should be mentioned that because of the hydrophobicity property in permanent organochlorine compounds, they are absorbed by organic parts of sediments at sea floor environment. Sea floor is the main source of organochlorine toxins in 291

Marine Pollution Bulletin 133 (2018) 289–293

P. Nejatkhah Manavi et al.

Fig. 3. Sum ± standard deviation of organochlorine pesticide concentrations (ppb) in L. aurata in different sampling sites.

Fig. 4. Mean ± standard deviation of individual organochlorine pesticide concentrations (ppb) in R. frisii kutum.

Fig. 5. Sum ± standard deviation of organochlorine pesticide concentrations (ppb) in R. frisii kutum in different sampling sites.

Fig. 6. Comparison of organochlorine pesticide concentrations between R. frisii kutum and L. aurata.

Determination of maximum residue limit for toxic compounds by each health organization and hygiene institute worldwide is on the basis of a specific criterion. The limit for organochlorine compounds is presented in Table 3. In this research, the measured compounds were less than the determined allowable limit. Acceptable daily intake is measured per kilogram of human weight.

Table 3 Maximum residue limits (MRLs) set by the European Commission (EC, 2005).

MRL (ppb)

∑DDT

Dieldrin

Endrin

∑endosulfans

γ-HCH

α-HCH

β-HCH

1000

200

50.

50

10

200

100

292

Marine Pollution Bulletin 133 (2018) 289–293

P. Nejatkhah Manavi et al.

World Health Organization (WHO) and Food and Agriculture Organization (FAO) have determined ADI for each toxin. It should be noted that ADI differs for various human weights, and the individual weight was 70 kg in this investigation. On the other hand, we calculated the maximum allowable limit for fish meat that could be consumed by a 70-kg person per each day. According to standards adopted by the WHO and FAO, the levels of dieldrin, aldrin, and lindane in L. aurata as well as dieldrin and aldrin in R. frisii kutum were more than ADI. Agricultural wastewater seems to be one of the most important pollution sources in provinces located at the southern Caspian Sea. The wastewater contains a range of harmful pollutants endangering marine life and finally human beings after discharge into the sea. Preventing the increasing trend of consumption of harmful agricultural pesticides and implementation of combined campaigns in farms and gardens can be effective to reduce the discharge of pollution load into the Caspian Sea.

input into the ecosystem. Can. J. Fish. Aquat. Sci. 41, 840–844. Andersen, G., Kovacs, K.M., Lydersen, C., Skaare, J.U., Gjertz, I., Jenssen, B.M., 2001. Concentrations and patterns of organochlorine contaminants in white whales (Delphinapterus leucas) from Svalbard Norway. Sci. Total Environ. 264, 267–281. Ballschmiter, K., Buchert, H., Scholz, C., Zell, M., 1983. Baseline studies of the global pollution by chlorinated hydrocarbons in the Caspian Sea. Fresenius Z. Anal. Chem. 316, 242–246. Connell, D.W., Miller, G.J., Mortimer, M.R., Shaw, G.R., Anderson, S.M., 1999. Persistent lipophilic contaminants andother chemical residues in the southern hemisphere. Crit. Rev. Environ. Sci. Technol. 29, 47–82. EPA, 1992. Guidelines for Exposure Assessment. Environmental Protection Agency, USA. EPA, 2004. National Water Quality Inventory. United States Environmental Protection Agency, USA. European Commission, 2005. EU Pesticides database - European Commission: Regulation (EC) 396/2005. http://ec.europa.eu/food/plant/pesticides/eu-pesticides-database (Accessed date: 25 May 2017). Francour, P., Boudouresque, C.F., Harmelin, J.G., Harmelin-Vivien, M.L., Quignard, J.P., 1994. Are the Mediterranean waters becoming warmer? Information from biological indicators. Mar. Pollut. Bull. 28, 523–526. Gerber, R., Smit, N.J., Van Vuren, J.H.J., Nakayama, S.M.M., Yohannes, Y.B., Ikenaka, Y., Ishizuka, M., Wepener, V., 2016. Bioaccumulation and human health risk assessment of DDT and other organochlorine pesticides in an apex aquatic predator from a premier conservation area. Sci. Total Environ. 550, 522–533. Judd, N., Griffith, W.C., Faustman, E.M., 2004. Contribution of PCB exposure from fish consumption to total dioxin-like dietary exposure. Regul. Toxicol. Pharmacol. 40, 125–135. MOOPAM, 1999. Manual of Oceanographic Observation and Pollution Analysis Methods. Pastor, D., Biox, J., Fernandez, M.C., Albaiges, J., 1996. Bioaccumulation of organochlorinated contaminants in three estuarine fish species (Mullus barbatus, Mugil cephalus, Dicentrarchus labrax). Mar. Pollut. Bull. 32, 257–262. Pinet, R., 2006. Invitation to Oceanography, fourth edition. Jones and Bartlett Publishers. Walker, C.H., 2001. Organic Pollutants – an Ecotoxicological Perspective. 282 Taylor and Francis, London. Zhou, R., Zhu, L., Kong, Q., 2007. Persistent chlorinated pesticide in fish species from Qiantang River in East China. Chemosphere 68, 838–847.

Acknowledgment We appreciate Mr. Ali Reza Daryazade from Iran Wood and Paper Industries – Chouka – and Mr. Hamid Fathaliyan and Mr. Mehrdad Akbari Tabrizi from Islamic Azad University, Science and Research Branch, who cooperated in the preparation of fish samples. References Aguilar, A., 1984. Relationship of DDE/PDDT in arine mammals to the chronology of DDT

293