Concentration and distribution of hydrophobic organic contaminants and metals in the estuaries of Ukraine

Marine Pollution Bulletin 58 (2009) 1103–1115

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Concentration and distribution of hydrophobic organic contaminants and metals in the estuaries of Ukraine Robert M. Burgess a,*, Anna V. Terletskaya b, Mykhailo V. Milyukin b, Mark Povolotskii c, Victor Y. Demchenko b, Tatiyana A. Bogoslavskaya b, Yuri V. Topkin b, Tatiyana V. Vorobyova b, Alexei N. Petrov d, Artem Lyashenko e, Kay T. Ho a a

US Environmental Protection Agency, ORD/NHEERL Atlantic Ecology Division, 27 Tarzwell Drive, Narragansett, RI 02882, USA Institute of Colloidal Chemistry and Chemistry of Water, National Academy of Sciences, 42 Vernadsky Boulavard, Kyiv, Ukraine Institute of Organic Chemistry, National Academy of Sciences, 5 Murmanskaya Street, Kyiv, Ukraine d Institute of Biology of the Southern Seas, National Academy of Sciences, 2 Nakhimov Avenue, Sevastopol, Ukraine e Institute of Hydrobiology, National Academy of Science, 12 Geroyiv Stalingrada Prospect, Kyiv, Ukraine b c

a r t i c l e

i n f o

Keywords: Estuaries Sediments Baseline hydrophobic organic contaminants Baseline metals Ukraine Black Sea

a b s t r a c t In this study of Ukrainian estuaries, sediments and tissues from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contaminant analyses included several metals, the hydrophobic organic chemicals (HOCs) polychlorinated biphenyls, several chlorinated pesticides, and polycyclic aromatic hydrocarbons. When compared to estuarine sediments globally, the Ukrainian sediments were found to be moderately contaminated. However, several metals, especially mercury, were often shown to be elevated in the tissues of the Ukrainian organisms in comparison to organisms from other estuarine locations. Sediment quality guidelines indicate some of the estuarine sediments could be sufficiently contaminated to cause adverse toxicological effects. This investigation represents the first extensive study of HOC and metal baseline concentrations and distributions in Ukrainian estuaries and seeks to characterize exposures to aquatic organisms living in these systems. Published by Elsevier Ltd.

1. Introduction Estuaries along the southern coast of Ukraine on the Black Sea have been the subject of only limited study for levels of sediment and organism contamination by anthropogenic municipal, industrial and agricultural chemicals. Conversely, following the devastating Chernobyl nuclear accident in 1986, several studies examined levels of radionuclides like cesium-137 and strontium90 in the Dnieper Estuary (e.g., Polikarpov et al., 1991; Vakulovsky et al., 1994; Sansone et al., 1996). In the UNESCO sponsored Black Sea Global Ocean Observing System (GOOS) workshop of 1999, collection of contaminant data was listed as an overall objective of continued monitoring of the Ukrainian Black Sea coastline (UNESCO, 2002). However, only a few studies have examined the concentration and distribution of conventional pollutants like hydrophobic organic contaminants (HOCs) including pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals like copper, mercury and lead. Fillmann et al. (2002) and Readman et al. (2002) reported * Corresponding author. Tel.: +1 401 782 3106; fax: +1 401 782 3030. E-mail address: [email protected] (R.M. Burgess). 0025-326X/$ - see front matter Published by Elsevier Ltd. doi:10.1016/j.marpolbul.2009.04.013

concentrations of several HOCs including pesticides, PCBs, PAHs and petroleum in sediments from sites along the western and southern coastal portions of the Black Sea (primarily in Romanian/Bulgarian/Turkish waters) with limited sites sampled along the Ukrainian and Russian coastlines. In these studies, samples were not collected from the estuarine areas of Ukraine (e.g., Dnieper and Boh estuaries). Several studies have reported PAH concentrations in or near the Danube Delta (e.g., Wakeham, 1996; Maldonado et al., 1999). In addition, in the Dnieper estuary and Danube Delta, elevated concentrations of some toxic heavy metals including cadmium, copper and zinc have been detected (Linnik and Zubenko, 2000; Lamborg et al., 2008; Yigiterhan and Murray, 2008). The objective of this study was to conduct an intensive baseline evaluation of the concentration and distribution of HOCs and heavy metals in four riverine and estuarine systems along the southern coast of Ukraine. The systems included the Dnieper and Boh estuaries and Danube Delta on the Ukrainian mainland coast, Sevastopol Bay and Balaklava Bay on the Crimean peninsula, and Black Sea along the Crimean peninsula. The Dnieper and Danube rivers and estuaries drain large watersheds (503,000 and 817,000 Km2, respectively) distributed across several European countries.

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As a result, they have the potential to accumulate elevated suspended particulate loads of anthropogenic chemicals from municipal, industrial and agricultural sources which are ultimately deposited into the Black Sea (Bakan and Buyukgungor, 2000; UNEP, 2008). Sevastopol and Balaklava Bays drain relatively smaller watersheds, 436 Km2 and 27 Km2, respectively, on the Crimean peninsula but have experienced decades of heavy industrial activity including naval inputs and some agricultural wastes (Oven, 1993; Gordina et al., 2001; Osadchaya et al., 2003; Ovsyaniy et al., 2003; Revkov et al., 2008; Wilson et al., 2008). For example, Sevastopol Bay has been the base for the Black Sea naval fleet of Czarist Russia, the Soviet Union, Ukraine and the Russian Federation. By comparison, the off-shore Black Sea stations studied here represent a relatively uncontaminated area. For this study, sediment samples and a limited number of tissue samples were collected from a total of 77 stations in 2006. Sediment samples were analyzed for PCBs, PAHs, organochlorine pesticides, and a suite of metals. In addition, sediments were analyzed for particle size distribution (i.e., clay, silt, sand) and elemental composition (including organic carbon, hydrogen, nitrogen, sulfur). Tissues were also analyzed for lipid content. This study is part of a larger multi-institution investigation to better understand and diagnose the causes of the adverse ecological and toxicological effects of anthropogenic contamination on Ukrainian estuaries. This part of that investigation represents the first extensive study on the concentrations and distributions of HOCs and metals in Ukrainian estuaries and seeks to characterize the exposures to aquatic organisms living in these systems.

2. Materials and Methods 2.1. Sampling Stations Surface sediment (0 – 7 cm depth) and organism samples were collected during September-October 2006. In the Dnieper and Boh estuaries 16 stations were sampled, 15 stations in the Danube Delta, 25 stations from Sevastopol Bay, 16 stations from Balaklava Bay, and five stations along the southwestern coast of the Crimean peninsula (Black Sea) (Fig. 1). Sediments, and associated organisms, from all stations were collected using a Petersen grab-corer (0.04 m2). Sediments from Sevastopol and Balaklava Bays and the Crimean Peninsula (Black Sea) were also collected with diver assistance, if necessary. 2.2. Analytes All sediment and tissue samples were analyzed for the metals Ag, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. Samples were also analyzed for the PAHs acenaphthene, acenaphthylene, anthracene, benzo(a)anthracene, benzo[a]pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo[ghi]perylene, chrysene, dibenzo[ah]anthracene, fluoranthene, fluorine, indeno[1,2,3dc]pyrene, naphthalene, phenanthrene and pyrene and total PAHs, total PCBs, and the organochlorine pesticides 4,4’- DDD, 4,4’- DDE and 4,4’- DDT, and total DDTs. Sediment and tissue concentrations are reported on a dry weight basis unless otherwise noted. 2.3. Analyses In general, analyses followed procedures described in Mitropolsky et al. (2006). Briefly, sediments were prepared for analysis by air drying and sieving (normally 1-2 mm), and stored at 4oC prior to analysis. Tissues were homogenized with a blender and stored at -24oC prior to analysis. Sediment and tissue extractions for metals were performed with concentrated acids and an oxidant (e.g.,

HNO3, HCl, H202) using US EPA Method 3051A (US EPA, 2007) with microwave digestion assistance in teflon pressurized vessels (Berghof Products + Instruments GmbH, Eningen, Germany). For sediments, nine milliliters of HNO3, and three milliliters of HCl were added to 0.5 – 1.0 g (dry weight) of subsample and digested in closed vessels at 175°C for 30 min. Vessel contents after cooling were filtered (polyvinylchloride membrane, 0.45 lm) and diluted to 25 ml. For tissue digestion, 0.5 g (dry weight) or 4-5 g (wet weight) of subsample was placed in a digestion vessel, 12 ml of HNO3 added, and the closed vessels digested at 160 °C – 170 °C for 30 min. Digestion vessels were opened, H2O2 added, and contents volume reduced to 3-4 mL. Extracts were then dissolved in nitric acid and filtered (polyvinylchloride membrane, 0.45 lm). Standard solutions were prepared from individual metal salts or mixtures (Intercountries Standard Samples, Physicochemical Institute, Odessa, Ukraine). Metal concentrations were determined by graphite (Saturn Graphite-2, Chemavtomatika, Severodonesk, Ukraine) and flame (C-115-M1, Electron, Symu, Ukraine) atomic absorption spectrometry (AAS). Detection limits ranged from 0.005-0.025 mg/kg (dry weight) for graphite AAS and 3 – 6 mg/ kg (dry weight) for flame AAS. Mercury analyses were performed by cold vapor AAS with detection limits of approximately 0.04 lg/kg (dry) (Yliya-2, Penza, Russia). Pesticides, PCBs and PAHs were extracted by Soxhlet for 16 hours with a hexane/acetone (1:1) mixture (sediments) or methylene chloride (tissue). Pesticide and PCB extracts were treated with concentrated H2SO4 and oleum (concentrated H2SO4 saturated with SO3) to remove interfering organic compounds. Standard solutions were prepared using a US EPA pesticide mixture (Supelco 48858-U, Bellefonte, PA, USA), Aroclor 1254 (Supelco 4-8707), Aroclor 1260 (Supelco 4-8704), and US EPA PAH mixture (Supelco 4S-8743). Pesticides and PCBs were determined by gas chromatography/mass spectroscopy (GC/MS) in SIM mode (Hewlett-Packard (HP)) 5890 series II (Palo Alto, CA, USA) with Agilent 6890N GC and 5975 inert MS detector (Agilent Technologies, Santa Clara, CA, USA). Pesticides were analyzed by GC/electron capture detector (ECD) (HP G1223) (Waldbrann, Germany). PAHs were also analyzed by GC/MS as well as HPLC/UV in reverse-phase mode (HP 1050 UV diode array detector). Detection limits averaged approximately 1.0 lg/kg (dry weight) and 10-20 lg/kg (dry weight) for pesticides/PCBs and PAHs, respectively. Sediment fractions, sand (1.00 – 0.05 mm), silt (0.05 – 0.001 mm) and clay (6 0.001 mm) were determined gravimetrically with wet sieving and sedimentation. Elemental analysis was performed on sediment samples for organic carbon, nitrogen, hydrogen, and sulfur using preparation methods described by Ryba and Burgess (2002) and instrumentation described by Klimova (1975) and Helman (1987). Elemental analysis detection limits were approximately 0.3%. Tissue lipid content was determined gravimetrically using a subsample of the Soxlet methylene chloride solvent extracts. 2.4. Quality Assurance Analyses for contaminants were conducted in duplicate or triplicate on homogenized samples. Median and range values are shown in the tables while means are reported in the figures. For organic and metal contaminants, variability between replicates was approximately 10-15% and represents preparatory (i.e., homogenization) and instrumental uncertainty. For elemental analyses, variability between replicates was approximately 0.3%. Blanks, duplicates, matrix spikes, and control samples were performed throughout the analyses. United States National Institute of Standards and Technology (NIST, Gaithersburg, MD, USA) standard reference materials (SRMs) including SRM 1944 (New York – New Jersey Waterway Sediment) and SRM 2977 (Mussel Tissue)

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Fig. 1. Sampling stations in (a) the Dnieper and Boh estuaries and Danube Delta, and (b) Sevastopol Bay, Balaklava Bay on the Crimean peninsula and southwestern coast of Crimean Peninsula (Black Sea).

were also used to confirm method accuracy. For SRM 1944, metal recoveries ranged from 76 - 98% with a mean of 92% while organic contaminant recoveries ranged from 84 – 143% with a mean of 108%. In SRM 2977, metal recoveries were 59 – 113% with a mean of 89% while organic contaminants ranged from 97 – 105% with a mean of 102%. For the elemental analyses, sulfanilic acid (C6H7NO3S), sulfanilamide (C6H8N2O2S) and 4-chlorobenzoic acid (C7H5ClO2) were used to confirm the accuracy of analyses. Recoveries of elements using these reagents ranged from 95 - 100%. Any analyses not meeting quality assurance requirements were re-analyzed.

2.5. Calculation of Sediment Quality Guidelines For this study, possible adverse effects to benthic organisms were evaluated by comparing measured contaminant concentrations to empirical and mechanistic sediment quality guidelines (Long et al., 1995; US EPA, 2003, 2005, 2008; Wenning et al., 2005). For this analysis, empirical guidelines included the effects range – median (ERM) developed by Long et al. (1995). Empirical guidelines were available for cadmium, chromium, copper, nickel, lead, silver, zinc and mercury, total PAHs, total DDTs and total PCBs. These guidelines were derived by matching toxicological

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3. Results and Discussion 3.1. Sediment Characteristics Dnieper, Boh and Danube Delta estuarine sediments were primarily sandy in composition with the exception of stations 14, A, F, H, I and L having silt levels of up to 80% (Fig. 2a). None of these stations had elevated clay. In contrast, the Sevastopol and Balaklava Bays sediments were dominated by silt and clay in the inland portions of the estuaries and then transitioned to higher sand contents at stations closer to the higher wave and tidal energy of the Black Sea (Fig. 2b). Two Crimean estuarine stations, 11 and C, also had high levels of gravel and shells. Finally, the two Crimean Peninsula stations analyzed for grain size were composed primarily of silt and sand (IV) or just sand (V) (Fig. 2b). Carbon content of the Dnieper, Boh and Danube Delta estuarine sediments ranged from below detection (<0.3%) to about 4% (Fig. 3) (Table 1). Hydrogen contents ranged from below detection to 1.1% and nitrogen and sulfur values were below detection to 0.7% and below detection to 1.4%, respectively (Table 1). Sevastopol and Balaklava stations

a 100 80

Composition (%)

and chemical data from many studies. From the matched data set, the ERM was derived for each chemical to represent the sediment concentration for which adverse effects are likely to occur. The ERM quotient was calculated by dividing sediment concentrations at each Ukrainian station by the ERM value for a given contaminant (Long et al., 2006). A quotient of one or greater may suggest potential for adverse benthic effects. Mechanistic guidelines were based on the equilibrium partitioning sediment benchmarks (ESB) developed by the U.S. Environmental Protection Agency (US EPA, 2003, 2005, 2008). Whereas the empirical guidelines are based on an assumed cause and effect relationship between the contaminant sediment concentration and toxicity, the ESBs determine the bioavailable concentration of a given contaminant in the sediment and compare it to known toxicity values (e.g., LC50s, final acute values (FAVs)). ESBs were available for total PAHs and DDTs. ESBs for several of the metals measured in this study are available but require the measurement of the sediment acid volatile sulfide (AVS). This is the sedimentary phase that sequesters many metals reducing their bioavailability (US EPA, 2005). AVS was not measured in this study. Unless PCBs are present at very high sediment concentrations, the most potent mode of action for total PCBs is generally of principle concern to higher level organisms (e.g., birds, wildlife, humans) and not benthic organisms (NRC, 2001). Further, calculating PCB bioavailability requires toxicity information about individual PCB congeners to benthic organisms; this type of information is currently limited. The bioavailable concentrations of PAHs and DDTs were estimated using the chemical’s octanol water partition coefficient (KOW), organic carbon normalized partition coefficient (KOC) and a known water-only effect concentration. KOWs were taken from Karickhoff and Long (1995) or US EPA (2003), and KOC derived from US EPA (2008) based on Di Toro et al. (1991). Water-only effect concentrations (e.g., FAV) for DDT are from US EPA (1980) and for individual PAHs from US EPA (2003). Toxic units were calculated by dividing the organic carbon normalized sediment concentration (lg/gOC) of each contaminant by the appropriate ESB value. One toxic unit is equivalent to the amount of chemical necessary to cause 50% mortality of test organisms. Like the ERM quotients, toxic units of one or greater may suggest potential for adverse benthic effects. For the total DDTs, one KOW and FAV was used for all three DDT isomers (i.e., DDT, DDE, DDD) while for the PAHs, based on the narcotic mode of action (US EPA, 2003), individual toxic units were calculated and then summed for total PAH toxic units.

60

40

20

0 3

1 2

5 4

7 6

9 11 13 15 A C E G I K M O 8 10 12 14 16 B D F H J L N

Clay Silt Sand

Stations

b 100 80

Composition (%)

1106

60

40

20

0 1 3 5 6 8 10 12 14 16 18 20 28 31 B D F H J L N P II IV 2 4 5a 7 9 11 13 15 17 19 25 29 A C E G I K M O I III V

Clay Silt Sand Gravel

Stations Fig. 2. Grain size composition of sediments collected from (a) Dnieper and Boh Estuary (1-16) and Danube Delta stations (A – O) and (b) Sevastopol Bay (1-31), Balaklava Bay (A-P), and southwestern coast of Crimean Peninsula (Black Sea) (I-V) stations. Analyses not performed on Crimean Peninsula stations I, II and III. Mean values reported.

tended to have greater elemental concentrations of carbon and hydrogen than did the mainland coastal estuaries with carbon ranging from 1.3% to 10% with a declining trend as sediments increased in sand content (Fig. 3) (Table 1). Hydrogen ranged from 0.5% to 3.5%. By comparison, Sevastopol and Balaklava nitrogen and sulfur concentrations were similar to the Dnieper, Boh and Danube Delta estuaries with nitrogen below detection to 0.5% and sulfur below detection to 1.1%, respectively (Table 1). Crimean Peninsula sediments ranged in carbon content from about 1% to, a somewhat surprisingly high, 7%, with hydrogen, nitrogen and sulfur ranging from 0.4% to 4%, below detection, and below detection to 0.4%, respectively (Table 1). In general, these elemental concentrations are not unusual for estuarine and marine sediments (e.g., Middelburg et al., 1999) and the observation of elevated organic carbon in Sevastopol Bay agrees with the tendency for sediment carbon to positively correspond with increasing anthropogenic contamination (see discussion below). 3.2. Contaminant Concentrations For this discussion, the metals were divided into three categories: cationic metals (i.e., cadmium, copper, nickel, lead, silver and zinc), mercury, and the anionic metal chromium. These categories were used because, in sediments, the cationic metals all show sim-

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a

5

Carbon (%)

4

3

2

1

0 1

3 2

5 4

7 6

9 8

11 13 15 A C E G I K M O 10 12 14 16 B D F H J L N

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b 12 10

Carbon (%)

8

6

4

2

0 1 3 5 6 8 10 12 14 16 18 20 28 31 B D F H J L N P II IV 2 4 5a 7 9 11 13 15 17 19 25 29 A C E G I K M O I III V

Stations Fig. 3. Organic carbon content of sediments collected from (a) Dnieper and Boh Estuary (1-16) and Danube Delta stations (A-O) and (b) Sevastopol Bay (1-31), Balaklava Bay (A-P) and southwestern coast of Crimean Peninsula (Black Sea) (I-V) stations. Mean values reported.

ilar geochemical behavior while mercury demonstrates unique geochemical behavior (e.g., methylation), and chromium has multiple oxidation states and is anionic (Bodek et al., 1988). Total cationic metals concentrations in the Dnieper and Boh estuary ranged from about 10 to about 830 mg/kg with a median value of 33 mg/kg (Table 1). Zinc with a median concentration of 18 mg/kg was the most abundant metal with levels approaching 700 mg/kg. Mercury in these estuaries ranged from less than 1 to 7 mg/kg with a median value of about 4 mg/kg. Chromium concentrations were also relatively high ranging from about 6 to 400 mg/kg and had a median of 36 mg/kg. In the Danube Delta, total cationic metals ranged from 39 to 200 mg/kg with a median of 104 mg/kg (Table 1). As in the Dnieper and Boh estuary, the dominant metal was zinc (median = 58 mg/kg). Chromium was also abundant ranging from 40 to 140 mg/kg and median of 100 mg/kg. Mercury ranged from 2 to 16 mg/kg with a median of 5.4 mg/kg. Recently, Yigiterhan and Murray (2008) reported metal concentrations in sediments collected in 2002 from the Romanian Sulina branch of the Danube Delta. They found metal concentrations comparable to measurements from the current study as well as some metals with levels that were up to seven times greater. Further, in the suspended solids (SS), metal concentrations were up to 90 times greater. This type of enrichment is often observed in SS reflecting the greater metal affinity of the less dense, organic carbon-rich material compared to bedded sediments (Cantwell et al., 2002). In their mercury mass balance for the Black Sea, Lamborg et al. (2008) proposed rivers like the Danube and Dnieper act as likely mercury sources to the sea. Mercury concentrations measured in the current study in the Danube and Dnieper estuarine sediments are higher than observed at many other estuaries globally (see discussion below) and would support Lamborg et al. (2008) speculation. In Sevastopol Bay, total cationic metals ranged from 115 to 2210 mg/kg with a median value of 371 which is about five times greater than observed in the mainland estuaries (Table 1). Balaklava Bay total metal concentrations were slightly larger ranging from 149 to 2490 mg/kg with a median of 521 mg/kg, about seven times greater than the mainland estuaries. Dominant cationic metals in these estuaries were copper, nickel, lead and zinc.

Table 1 Median and range of elemental, metal and HOC concentrations in surface sediments collected in 2006 from four Ukrainian estuaries and along the southwestern coast of the Crimean peninsula (Black Sea). Analyte

Estuary Dnieper and Boh estuaries

Danube Delta

Sevastopol Bay

Balaklava Bay

Black Sea

Elements (%) Carbon Hydrogen Nitrogen Sulfur

0.7 0.6 0.6 0.8

1.0 0.6 0.3 0.4

6.0 1.6 0.3 0.3

2.7 1.4 0.3 0.3

1.5 (0.9–7.2) 1.4 (0.4–4.0) nd a (nd–0.4)

Metals (mg/kg dry) Cd Cu Ni Pb Ag Zn Total metals (not including Cr and Hg) Cr Hg

0.15 (nd–10) 7.5 (1.5–138) 8.5 (2.5–40.7) 2.13 (0.65–23) 0.13 (nd–2.03) 17.8 (2.5–650) 33.3 (9.71–828) 36.3 (6.2–378) 3.5 (0.3–6.9)

0.15 (0.05–0.58) 12 (0.8–55) 23.8 (4.0–36.2) 6.25 (1.28–12.0) 0.10 (nd–8.0) 57.5 (22.3–110) 104 (39.1–201) 100 (40–140) 5.4 (2.0–16.3)

0.25 (0.05–1.18) 81 (21.2–419) 34.5 (12–50) 113 (5–1120) 0.3 (0.05–2.5) 170 (37.5–675) 371 (115–2210) 32.2 (9.25–88.8) 0.53 (0.17–18)

0.26 (0.05–0.63) 130 (33.8–350) 32.5 (9–44) 183 (51.2–1500) 0.33 (0.03–0.58) 182 (53–600) 521 (149–2490) 30.9 (2.5–67.5) 0.65 (0.25–2.00)

0.03 (0.02–0.13) 13.2 (10–37.2) 7.80 (2.80–36.8) 21.9 (9.5–40) 0.03 (0.03–0.13) 27 (17.5–53) 65.5 (30.5–151) 14.2 (9.3–21.5) 0.13 (0.10–0.14)

Organics (lg/kg dry) Total PAHs Total DDTs Total PCBs

120 (30–13500) 24.2 (6.0–59.4) 13.1 (nd–117)

164 (119–4940) 24.7 (nd–69.8) 11.8 (nd–28.5)

2410 (nd -30100) 16.5 (nd–77.7) 261 (60.0 -1980)

5550 (nd–26000) 16.0 (nd–93.0) 111 (nd–435)

a

nd–Not detected. a One sample above detection limits.

(nd–4.3) (nd -1.0) (0.4–0.7) (nd–1.4)

(0.4–3.0) (0.4–1.1) (nd–0.3) (nd–0.7)

(2.2–9.9) (0.6–3.5) (nd–0.5) (nd -1.1)

(1.3–6.6) (0.5–3.0) (nd–0.5) (nd–0.4)

(nd–351) (nd–1.5) 3.6 (nd–4.2)

a

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Compared to the mainland estuaries, mercury levels in Sevastopol and Balaklava Bays were relatively low (< 1 mg/kg) except for a small number of stations where concentrations spiked from about 2 to almost 20 mg/kg. Chromium concentrations in the Crimea were similar across estuaries ranging in concentration from about 3 to 90 mg/kg with a median of about 30 mg/kg dry. Metals present in the Crimean Peninsula sediments were at relatively low concentrations. For example, median mercury and chromium concentrations did not exceed more than 1 mg/kg or 15 mg/kg, respectively, but the median for total cationic metals (66 mg/kg) exceeded the median for the Dnieper and Boh estuary suggesting anthropogenic activities in estuaries like Sevastopol and Balaklava Bays result in substantial metal contamination causing the estuaries to serve as a source exporting metals like copper, nickel, lead and zinc to the Black Sea. Both the Dnieper and Boh estuaries and Danube Delta sediments demonstrated similar median organic contaminant concentrations. In the Dnieper and Boh estuaries, concentrations of total PAHs ranged from 30 to 14,000 with a median of 120 lg/kg (Table 1). PAHs concentrations in Danube Delta sediments ranged from 120 to 5,000 with a median of 160 lg/kg. The dominant PAHs in these sediments had less than three rings with naphthalene being particularly elevated in concentration. The dominance of low molecular PAHs is significant when considering contaminants sources to the estuaries (see discussion below). Total DDTs in the Dnieper and Boh estuaries ranged from 6 to 60 lg/kg with a median value of 24 lg/kg (Table 1). With similar concentrations, Danube Delta total DDTs ranged from not detected to 70 lg/kg and a median of 25 lg/kg. In the Dnieper and Boh estuaries and Danube Delta sediments, the dominant form of the pesticide was DDT (4565% of total) with slightly lesser amounts of DDD (19-37% of total). The stable transformation products of DDT, DDD and DDE, both occur as impurities during industrial DDT synthesis and abiotic and biotic reactions: reductive dechlorination (DDD) and dehydrochlorination (DDE) (Foght et al., 2001). As such, the distributions of DDT, DDD and DDE in Ukrainian estuarine sediments reflect the batches of DDT applied during agricultural use and environmental conditions. Finally, in the Dnieper and Boh estuaries, total PCBs ranged from below detection limits to about 120 lg/kg and had a median value of 13 lg/kg (Table 1). In the Danube Delta sediments, the concentrations were slightly lower ranging from not detected to about 30 lg/kg and having a median of 12 lg/kg. In the Sevastopol and Balaklava Bays estuaries on the Crimean peninsula, median organic contaminant concentrations were generally similar but higher by an order of magnitude than those in the mainland estuaries. The exception to this observation was the DDTs which had similar median sediment concentrations across all of the Ukrainian estuaries. In the Crimea, total PAHs ranged from below detection to about 30,000 lg/kg with a median values of 2,400 and 5,600 lg/kg at Sevastopol and Balaklava Bays, respectively (Table 1). As discussed below, at the Crimean sites, the predominant PAHs had more than three rings and very few compounds with less than three were detected. For example, in contrast to the mainland sediments, in only one sediment was naphthalene detected while fluoranthene and pyrene class PAHs were frequently abundant. Total DDTs at Sevastopol Bay ranged from non-detected to about 78 lg/kg having a median value of 17 lg/kg which is very similar to the measured range (i.e., nd to 93 lg/kg) and median of 16 lg/kg for Balaklava Bay (Table 1). In the Sevastopol Bay sediments, DDD and DDT were the dominant DDT isomers (43 and 41%, respectively). At Balaklava Bay, the primary isomer was DDE (42%). Total PCBs in Sevastopol and Balaklava Bays sediments ranged from undetected to about 2,000 lg/ kg with median concentrations of 261 and 111 lg/kg, respectively. As noted above, these median concentrations are about an order of magnitude larger than those in the Dnieper, Boh and Danube Delta

estuaries. Finally, the Crimean Peninsula stations showed very little contamination, relative to the other estuaries (Table 1). Overall, the data show the Ukraine mainland and Crimean peninsula estuaries had similar sedimentary loads of total DDTs. In contrast, total PAHs and PCBs were about an order of magnitude higher in the Sevastopol and Balaklava Bays estuaries suggesting, as with the metals, the types of anthropogenic activities occurring there result in elevated contaminant concentrations. 3.3. Contaminant Distributions Around the Dnieper and Boh estuaries, contaminant distributions did not appear to demonstrate any strong patterns or gradients (Figs. 4 and 5). For example, total metals and chromium followed a very similar distribution with a Pearson correlation coefficient (r) of 0.96 and elevated concentrations at Stations 2, 7, 11 and 14 (Fig. 4). Mercury, unlike the other metals, peaked at Stations 5, 6, 12, 15 and 16. Total PAHs were relatively uniformly distributed with elevated concentrations occurring primarily at Stations 7 and 10 (Fig. 5). Both total DDTs and PCBs showed a weak pattern in which stations near the city of Kherson (e.g., Stations 2, 3, 4, 5) were elevated and then declined as distance from the city increased. However, the PCB peak at Station 4 appears to overwhelm this trend. Station 14 just south of the city of Mykolayiv also had elevated concentrations of total DDTs and PCBs. In the Danube Delta sediments, all of the metals were relatively uniformly distributed, with mercury and chromium peaking at Stations E, G, J, M and N, and A, E, F, I, L, M, N, and O, respectively (Fig. 4). Total PAHs, DDTs and PCBs peaked at the common Stations E and H with the total DDTs and PCBs also peaking at Stations A, I and L, and A, F, G and L, respectively (Fig. 5). Like the Dnieper and Boh estuaries, the Danube Delta did not show any strong patterns except for the commonality of elevated contaminants at Stations E and H as well as L. The Crimean sites demonstrated more consistent patterns in terms of contaminant distributions (Figs. 6 and 7). In Sevastopol Bay, for example, nearly all contaminants, including metals and HOCs, in the small embayment on the southern part of the bay, where Stations 17, 18, 19 and 20 are located, were elevated (Figs. 6 and 7). This embayment has been used for decades for ship construction and repair and is restricted geographically which may serve to trap contaminants (Fig. 1). Although chromium followed this pattern, it also demonstrated elevated concentrations in several other Sevastopol Bay stations. Chromium is used in several naval applications, especially those that involve enhancing corrosion and oxidation resistance (Johnson et al., 2006). Consequently, its presence in Sevastopol Bay is not surprising. Also, mercury did not follow the distribution demonstrated by other contaminants but instead peaked at Stations 25, 28, 29 and 31 (Fig. 6). These four stations are located along the shore of the bay and may be impacted more strongly by terrestrial runoff consisting of elevated mercury containing substances. In Balaklava Bay, elevated concentrations of total metals were focused primarily in the middle section at Stations H, I, J, K, L and M (Fig. 6). Chromium followed a somewhat similar pattern with peaks at Stations C, H, I, J and O. In contrast, mercury occurred at relatively low concentrations without any substantial peaking. Total PAHs peaked at widely distributed stations including C, H, M and N while total DDTs peaked at stations in the mid- to inner bay sections such as A, E, G, J and K (Fig. 7). Total PCBs were most abundant at Station E in the inner bay. At the Crimean Peninsula stations, very few peaks in any contaminants were observed with the unexpected exception of chromium at Stations I, III, IV and V. As mentioned above, the chromium likely results from use by the estuarine naval installations. Finally, as noted earlier, sedimentary organic carbon content is often found to correlate with the distribution of anthropogenic

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contaminants as organic carbon is a sorptive phase for both metals and HOCs (Di Toro et al., 1991). For the Ukrainian estuaries in this study, the correlation coefficients (r) for contaminant concentrations and carbon content were poor to moderate, ranging from 0.29 for mercury to 0.64 for total PCBs (when all stations were combined into one dataset). While specific contaminant sources are discussed below, differences between the estuaries and the ability to discern patterns in contaminant distributions are likely related to scale. As shown in Fig. 1, the Dnieper and Boh estuaries and Danube Delta are rela-

1

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11 13 15 A C E G I K M O 10 12 14 16 B D F H J L N

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tively large geographic features, tens of kilometers in length, while the Crimean estuaries are much smaller with lengths of less than ten kilometers. For the number of stations sampled, greater resolution and pattern delineation results for the Crimean estuaries while the mainland estuaries are much less well resolved. Complicating the identification of patterns in contaminant distributions in the Dnieper and Boh estuaries and Danube Delta are multiple pollutant transport mechanisms including riverine and coastal runoff. In contrast, the Crimean estuaries are most likely predominantly affected by coastal runoff because riverine flows are relatively minor. As noted above, for the mainland estuaries, contaminant transport

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Stations Fig. 6. Concentrations of (a) total cationic metals (cadmium, copper, nickel, lead, silver, zinc), (b) mercury and (c) chromium in Sevastopol Bay (1-31), Balaklava Bay (A-P) and southwestern coast of Crimean Peninsula (Black Sea) (I-V) sediments. Mean values reported.

by riverine and coastal runoff, including those from industrial activities around the cities of Mykolayiv and Cherson for the Dnieper and Boh estuaries, have the potential to introduce large quantities of waste. 3.4. Comparison to Other Global Sediments To place these Ukrainian sediment concentrations in a global and regional context, values in Table 1 were compared to the concentrations of total metals, mercury, chromium, total PAHs, to-

0

1 3 5 6 8 10 12 14 16 18 20 28 31 B D F H J L N P II IV 2 4 5a 7 9 11 13 15 17 19 25 29 A C E G I K M O I III V

Stations Fig. 7. Concentrations of (a) total PAHs, (b) total DDTs and (c) total PCBs in Sevastopol Bay (1-31), Balaklava Bay (A-P) and southwestern coast of Crimean Peninsula (Black Sea) (I-V) sediments. Mean values reported.

tal DDTs and total PCBs reported for other estuarine locations (Table 2). In Ho et al. (2002), concentrations of contaminants in several sites located in the United States (USA) are discussed. These sites include New Bedford Harbor (MA, USA) where total PCBs and total metal concentrations are reported to exceed 300 mg/kg and 2710 mg/kg, respectively, and Elizabeth River (VA, USA) where total PAHs exceed 1400 mg/kg. These sediments are recognized as among some of the most contaminated in the world; fortunately, the Ukrainian sediments do not approach these levels; even at the most contaminated sites the concentrations are one to three orders of magnitude less than those reported by Ho et al. (2002).

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R.M. Burgess et al. / Marine Pollution Bulletin 58 (2009) 1103–1115 Table 2 Range of contaminants in Ukrainian sediments from this study and concentrations of total metals, chromium, mercury and HOCs in sediments from selected locations. Sampling Locations

Total metals (mg/kg dry)a

Chromium (mg/kg dry)

Mercury (mg/kg dry)

Total PAHs (lg/kg dry)

Total DDTs (lg/kg dry)

Total PCBs (lg/kg dry)

This study Globally New Bedford Harbor (MA, USA)b Elizabeth River (VA, USA)b United States National Survey c Pearl River Estuary, China d Mediterranean Region Black Sea Region Ukraine coastg Turkish coasth Coastal/off-shorei

33–521

31–100

0.53–5.4

120–5550

16–25

12–261

2710 457 265 275 (87.9–518) 52–16,400 e

474 72.9 125 88.4 7–1800

0.22 0.01–139

112,000 1,450,000 2180 208–1849 1,400 (9–31,800)

22 1.36–28.6 37 (0.3–75,600)

304,000 473 80 0.18–2.49 151 (2–3,940)

51.5–400 -

10.8–116 -

e

-

e

7.2–638 12–2400

e

0.058–65 -

f

f

nd–6.82 -

- = not measured. a Not including chromium or mercury. b Ho et al. (2002); Individual site values. c Daskalakis and O’Connor (1995); United States coastal and estuarine stations (n = 224), ‘high’ values equivalent to the mean plus one standard deviation. d Ip et al. (2007); total metal median and range (n = 606) and Fu et al. (2003) range (n = 1 to 12) from the literature. e Sprovieri et al. (2007); survey of Naples Harbor (Italy) (n = 189), total metals range and total PAHs median and range. f Gomez-Gutierrez et al. (2007); survey of Mediterranean harbors (n = 22 to 60), median and range g Fillmann et al. (2002) and Readman et al. (2002); (n = 10), range. h Topcuoglu et al. (2002); (n = 6), range. i Wakeham (1996); (n = 14), range.

In comparison to a more representative sampling of USA estuarine sediments (Daskalakis and O’Connor, 1995), the Ukrainian sediment concentrations are similar in magnitude with total metals (265 mg/kg versus 33 – 520 mg/kg), chromium (125 mg/kg versus 31 to 100 mg/kg), total PAHs (2180 lg/kg versus 120 – 5550 lg/kg) and total DDTs (22 lg/kg versus 16 – 25 lg/kg) (Table 2). Only mercury and total PCBs were higher in the Ukrainian estuaries: 0.22 mg/kg versus 0.53 to 5.4 mg/kg and 80 lg/kg versus 12 – 260 lg/kg, respectively. A similar trend was observed when comparing the Ukrainian sediments to estuarine sediments from the Pearl River Estuary in China (Fu et al., 2003; Ip et al., 2007), again only the PCBs were notably higher in the Ukrainian estuaries (i.e., 0.18 – 2.49 lg/kg). In a survey of studies on Mediterranean harbors, Gomez-Gutierrez et al. (2007) reported median concentrations of HOCs that were similar in magnitude to the values detected in the Ukrainian estuaries, suggesting that the Black Sea, and more specifically the Ukrainian estuarine sediment concentrations, despite the geographic constrictions between the two water bodies (i.e., Dardanelles, Sea of Marmara, Bosporus Strait) are typical of the levels of contamination observed in parts of the Mediterranean. For total metals in the Mediterranean, the range reported by Sprovieri et al. (2007) for an intensive sampling of Naples Harbor (n = 189) was compared to the Ukrainian data. While the Ukrainian total cationic metals, chromium and mercury concentrations easily fall within the range reported for Naples Harbor, the Ukrainian upper range is an order of magnitude lower than the high of 16,400 mg/kg reported by Sprovieri et al. (2007). Further, concentrations of total PAHs in the Ukrainian sediments were within the range reported by Sprovieri et al. (2007). Finally, results of the current study can be compared to other studies performed in the Black Sea. For example, in their extensive evaluation of HOCs in ten sediments along the Ukrainian coast, Fillmann et al. (2002) and Readman et al. (2002) found concentrations lower for total PCBs and PAHs but modestly higher for total DDTs than in the current study. Wakeham (1996) also found similar total PAH concentrations in 14 stations from around the Black Sea. Total cationic metal and chromium concentrations in the Ukrainian estuaries were similar to values reported for six stations along the Turkish coast (Topcuoglu et al., 2002). This relatively limited comparison of sediment concentrations in the Ukrainian estuaries with locations around the world show the sites in this study, with the exception of the Crimean Peninsula stations, are comparable to moderately

contaminated locations while not approaching the elevated concentrations at some of the world’s most polluted locations. 3.5. Contaminant Sources Specific sources of the contaminants include metals and PCBs released by industry, like the ship construction and repair activity in Sevastopol Bay discussed above (Fedorov, 1999; Gritsan and Babiy, 2000; Kakareka et al., 2004; Pacyna et al., 2006), and DDTs from agriculture (Fedorov, 1999; Li et al., 2006). Mercury sources include industrial releases, like poor battery disposal practices, but also the burning of coal (Pacyna et al., 2006). In 2005, Ukraine burned 37,000 kilotonnes of oil equivalents (ktoe) of coal. Except for Russia (103,000 ktoe) and Poland (54,000 ktoe), this level of coal use exceeded many other central and eastern European countries like Bulgaria (6700 ktoe), the Czech Republic (20,000 ktoe), Georgia (16 ktoe), Hungary (3200 ktoe), Lithuania (189 ktoe), and Romania (8,600 ktoe) and challenged some western European countries like France (14,000 ktoe), Germany (82,000 ktoe) and the United Kingdom (34,000 ktoe) (IEA, 2005). This magnitude of coal burning and resulting mercury releases may assist in explaining the levels of mercury found in some Ukrainian estuarine sediments and organisms. PAHs can originate from at least two sources: (1) pyrolysis caused by incomplete burning of fossil fuels like coals and petroleum, and biomass and (2) petrogenic from petroleum (Burgess et al., 2003). In general, pyrogenic PAHs are spread through-out the environment by atmospheric transport on combustion particles and are consequently very often widely distributed. Conversely, petrogenic PAHs are frequently localized to petroleum and other hydrocarbon spills. Distinguishing between pyrogenic and petrogenic PAH sources can be performed by comparing the distribution of individual PAHs especially alkylated molecules that occur abundantly in petrogenic PAHs but less so in pyrogenic PAHs. Although alkylated PAHs were not measured in this study, a determination of PAH source was conducted by classifying individual PAH molecules as either primarily pyrogenic or petrogenic. Pyrogenic PAHs were defined as having more than three rings and included benzo(a)anthracene, benzo[a]pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo [ghi]perylene, chrysene, dibenzo[ah]anthracene, fluoranthene, indeno[1,2,3dc)pyrene and pyrene while petrogenic PAHs molecules had three rings or less including acenaphthene, acenaphthylene, fluorene,

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naphthalene and phenanthrene (Barrick and Prahl, 1987). Fig. 8 displays the distribution of pyrogenic and petrogenic PAHs in Ukrainian estuarine sediments. As is commonly observed globally (Burgess et al., 2003), Sevastopol and Balaklava Bays and the Crimean Peninsula sediments all show a predominantly pyrogenic source with pyrogenic PAHs making-up 92 ± 14% of total PAHs. Interestingly, in the Dnieper, Boh and Danube estuarine sediments, pyrogenic PAH contribution to total PAHs is only 33 ± 43% with petrogenic PAHs dominating. In fact, the contribution of one petrogenic PAH, naphthalene, to total PAH, was 65 ± 45%. In addition, to examining the distribution of designated pyrogenic and petrogenic PAHs, ratios of fluoranthene to fluoranthene + pyrene (FL:FL+PY) and anthracene to anthracene + phenanthrene (ANT:ANT+PH) were also used to distinguish between PAH types (Pies et al., 2008). Using these ratios, FL:FL+PY values greater than 0.5 are considered pyrogenic and ANT:ANT+PH values greater than 0.1 are pyrogenic. For Crimean sediments, the mean FL:FL+PY and ANT:ANT+PH ratios were 0.7±0.2 and 0.6±0.4, respectively, supporting the earlier conclusion that these sediments are primarily affected by pyrogenic PAHs. Unfortunately, in most cases for the Dnieper, Boh and Danube sediments, the PAHs necessary to generate the ratios were not detected. Of a total of 31 sediments, only 15 sediments had the required data, due to this limitation the ratios are not presented. Water samples collected in 1995 off-shore of the Danube Delta and Dnieper and Boh estuaries also found the suspended solids and dissolved phase to be dominated by petrogenic PAHs (Maldonado et al., 1999). They also re-

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Stations Fig. 8. Distribution of pyrogenic (solid bar) and petrogenic (open bar) PAHs from (a) Dnieper and Boh Estuary (1-16) and Danube Delta (A-O) sediments and (b) Sevastopol Bay (1-31), Balaklava Bay (A-P) and southwestern coast of Crimean Peninsula (Black Sea) (I-V) sediments.

ported the ratio of petrogenic to pyrogenic PAHs decreased with increasing distance from the coast suggesting, along with depositional processes, the petrogenic PAHs are localized to the estuaries. Further, they detected 17a-(H), 21ß(H)-hopanes and steranes, compounds very ubiquitous in crude oil. Wakeham (1996) and Readman et al. (2002) reported Black Sea sediments adjacent to the Danube Delta also were dominated by petrogenic PAHs. Specifically, Readman et al. (2002) found naphthalene was dominant in the sediments collected off of the Danube Delta. While the Black Sea basin is known to have naturally-occurring petroleum reserves (Robinson et al., 1996), it is not clear if the PAHs found in sediments around the Danube Delta are from natural seeps or due to anthropogenic sources. In summary, while the Crimean PAHs reflect the common pyrogenic PAH trend, the abundance of petrogenic PAHs, especially naphthalene, in the Dnieper, Boh and Danube sediments appears to be unusual and justifies future investigation. However, as discussed by Zonn et al. (2008), the Black Sea, in general, is the site of many petroleum spills a year; as an enclosed water body, these spills may explain some of the elevated petrogenic PAH concentrations observed in the coastal sediments. 3.6. Contaminant Bioavailability and Predicted Effects At a limited number of stations in the Dnieper and Boh estuaries and Danube Delta, organisms, primarily benthic filter-feeding bivalves, gastropods and amphipods, were also collected with the sediments. Except for silver and PAHs, all of the analytes were detected in the organisms (Table 3). In the Dnieper and Boh estuaries, the metals copper and zinc were most abundant while mercury was the least. The same trend was observed for metals in the Danube Delta except that mercury was more elevated. For organic contaminants, PAHs may not have been detected in the tissues due to organism metabolism as many benthic organisms have been shown to metabolize PAHs (Rust et al., 2004); however, the bioaccumulation of PAHs by marine organisms in other locations has been reported (Table 3). Total DDT and total PCB concentrations are also presented in Table 3 on a lipid normalized basis. Lipid concentrations in the organisms ranged from 3 to 13.9% (g lipid/g dry tissue*100). At both mainland sites, overall total DDT and total PCB concentrations were of a similar magnitude. In comparison to primarily filter-feeding mussel species and an oyster from different parts of the world, tissue concentrations for Ukrainian estuarine species were similar for cadmium but often higher for other metals. For example, for lead and chromium, the Ukrainian mainland estuarine organisms were about twice as elevated as compared to organisms from estuarine and marine sites in the United States, Canada, Italy and China and many times greater for copper and nickel (O’Connor and Lauenstein, 2006; Yeats et al., 2008; Fattorini et al., 2008; Perugini et al., 2004; Fung et al., 2004). Zinc in Ukrainian organisms was about two times higher than in other organisms except bivalves from the USA, where a concentration of 2000 mg/kg was reported (O’Connor and Lauenstein, 2006). Also, for mercury, the Ukrainian tissues were about 50 times greater than other organisms with the exception of a report from East China of mercury concentrations of 267 mg/kg (Fung et al., 2004). For total DDTs, the Ukrainian organisms demonstrated concentrations similar to those observed in North America but an order of magnitude lower than those reported for China which had a high of 640 lg/kg. When expressed on a lipid normalized basis, the Ukrainian organisms were more contaminated with total DDTs than were organisms collected from the Adriatic Sea (Perugini et al., 2004). Finally, for total PCBs, the concentrations on both a dry weight and lipid weight basis were comparable for all locations with values in the tens of lg/kg (dry) and hundreds of lg/kg (lipid), respectively. These tissue concentrations demonstrate contaminants in the mainland Ukrainian estuarine sediments are bioavailable and

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Table 3 Comparison of metal and HOC concentration ranges in organisms from mainland Ukrainian estuaries to organisms from selected locations. Values for organic contaminants in parentheses for the Dnieper and Boh estuaries and Danube Delta are lipid normalized (lg/kg lipid).–= not measured. Contaminants

Concentration range Dnieper and Boh Estuaries

Danube Delta

United Statesa

Halifax Harbor (Canada)b

Adriatic Sea (Italy)c,d

East Coast (China)e

Metals (mg/kg dry) Cd Cu Ni Pb Ag Zn Cr Hg

0.11–1.0 62–380 0.1–13.0 0.8–3.5 nd 48–290 nd–21 0.03–0.22

0.27–3.65 26–120 4.7–11 0.5–4.2 nd 35–359 14–26 0.06–4.8

2.1 8.0–120 1.8 0.77 – 110–2000 – 0.10

0.60 11.5 1.05 0.85 0.17 115 0.75 0.06

0.868–2.41 2.23–4.01 1.49–2.83 0.801–1.28 – 92.2–158 0.416–0.741 0.023–0.064

nd–4.96 nd–22.58 0.07–4.49 0.06–2.43 nd–0.12 nd–169.8 0.15–10.93 3.42–267.1

Organics (lg/kg dry) Total PAHs Total DDTs Total PCBs

nd 0.1–30.2 (2–521) 1.8–30 (95–640)

nd 6.5–19.6 (159–386) 9.2–31.2 (212–547)

220 13 50

428 1.8 –

– 159–210 337–752

489–3,300 14–640 1.34–13

nd – Not detected. a O’Connor and Lauenstein (2006); national median values for several mollusks species (Mytilus edulis, Mytilus californianus, Crassostrea virginica) sampled from 2002 to 2003 at 114 sites around the country. b Yeats et al. (2008); Contaminants in Mytilus trossulus. ‘Total DDT’ values are for p,p’ DDE only. c Fattorini et al. (2008); Metals in Mytilus galloprovincialis. d Perugini et al. (2004); Total PCBs and DDTs data (lg/kg lipid) in Mytilus galloprovincialis. e Fung et al. (2004); Contaminants in Mytilus edulis.

Table 4 Estuarine and coastal locations and stations where contaminant concentrations (mg/kg dry) exceeded empirical and mechanistic sediment quality guidelines. ERM (mg/kg dry)

ESB (lg/kg OC)

Stations with ERM Quotients or ESB Toxic Units Exceeding One Dnieper and Boh Estuaries

Danube Delta

Sevastopol Bay

Balaklava Bay

Black Sea

Metals (mg/kg dry) Cd Cu Ni Pb Ag Zn Cr Hg

9.6 270 51.6 218 3.7 410 370 0.71

a

2 – – – – 2 2 1, 3–7, 9–16

– – – – L – – A–O

– 18,19 – 17, 18, 19, 20 – 17, 18,19 – 11,15,16,18.19,20, 25, 28, 29, 31

– H – C, H, I, J, K, L, M – H – E, I, J, K, L, M

– – – – – – – –

Total PAHs Total DDTs Total PCBs

44.8 0.0461 0.180

b

– 14 –

– E,H,I,L –

– 17,18,19,25 3,5,5a,7,8,10,11,12, 13,14,15,16,17,18,19,20

– E E

– – –

Contaminant

a a a a a a

na

342 na

– = No exceedance. na – Not available. a Acid volatile sulfide (AVS) data was not collected and ESB cannot be calculated. b Calculated as the sum of individual PAH toxic units by station.

accumulate to levels observed in other organisms globally. In the case of the metals, the concentrations accumulated were often higher than observed elsewhere. Given that many of the contaminants measured in the Ukrainian sediments are bioavailable, the next consideration is whether or not these contaminants might cause adverse effects to the organisms living in the benthic environment (i.e., toxicity). Direct toxicological and ecological effects of these sediments to benthic organisms will be addressed in later reports. Table 4 shows the results of the analysis of sediment stations predicted to cause toxicity to benthic organisms based on empirical and mechanistic sediment quality guidelines. For metals, the empirical guidelines predict that in the Dnieper and Boh estuaries copper, nickel, lead and silver were unlikely to cause toxicity although at some stations nickel did approach an ERM quotient of one. Cadmium, chromium and zinc were predicted to cause tox-

icity only at Station 2. In contrast, mercury ERM quotients exceeded one at 88% of stations with a range of 1.1 to 9.7. The Danube Delta followed a similar pattern as the Dnieper and Boh estuaries, cadmium, chromium, copper, nickel, lead and zinc ERM quotients did not exceed one, although nickel had some quotients that were close. Silver had a quotient exceeding one at Station L while all of the stations had mercury ERM quotients exceeding one with a range of 2.8 to 23. As with the organic contaminants discussed below, in Sevastopol Bay more metals exceeded the ERMs than at any other Ukrainian site. For example, ERM quotients exceeded one at Stations 18 and 19; 17, 18, 19 and 20; 17, 18 and 19, for copper, lead and zinc, respectively. There were also several stations where lead and zinc were close to one. Cadmium, chromium and silver did not have ERM quotients exceeding one although nickel had several values that were close to one. Finally, also like the mainland estuaries, mercury ERM quotients exceeded

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one at 40% of stations with a range of values of 1.1 to 25. In Balaklava Bay, a similar pattern was followed. ERM quotients for cadmium, chromium, nickel and silver were all less than one but several nickel values were close to one. Copper and zinc quotients exceeded one at Station H with several stations close to one. Both lead and mercury had several stations where quotients exceeded one including stations C, H, I, J, K, L and M (44% of stations) and E, I, J, K, L and M (38% of stations), respectively. For both metals, for quotients exceeding one, the range was 1.1 to 4.1. Both metals also had several stations where the quotients were close to one. None of the Crimean Peninsula stations had ERM quotients exceeding one although Station IV had a nickel value approaching one (0.7). For organic contaminants, the empirical guidelines predicted that ten sediments would probably cause toxicity due to total DDTs, including four stations in Sevastopol Bay (Table 4). Total PCBs were predicted to cause toxicity at 17 stations all in the Crimean estuaries and 16 of them in Sevastopol Bay. Generally, the quotient values were slightly greater than one. However, in several cases, especially in Sevastopol Bay for total PCBs, quotients were two to four including at stations 8, 11, 14, 15, 16 and 17. Further, at two locations, quotients were eight and eleven at stations 18 and 19, respectively. The mechanistic guidelines predicted that none of the sediments would be toxic due to total DDTs. Neither type of guideline predicted sediment toxicity due to total PAHs. This analysis of predicted effects results in an interesting contrast: the empirical guidelines clearly would predict that many of the Ukrainian sediments, especially those from Sevastopol Bay, would be very toxic to benthic organisms while the mechanistic guidelines, though not as comprehensively applied as the empirical methods, suggest that at least the total DDT and PAHs are insufficiently bioavailable to contribute to toxicity. In principle, if both approaches reflected reality, they would reach similar findings. In this application with the Ukrainian estuarine sediments, we would expect the two guidelines to find the total DDTs and PAHs either contribute to toxicity or do not contribute to toxicity. Instead, the two approaches agree that total PAHs are not contributing to toxicity while disagreeing with each other regarding total DDTs. Because the two approaches for calculating sediment quality guidelines use different models (i.e., correlation versus bioavailability) such disagreements are not unexpected and can only be assessed for accuracy by comparison with the results of toxicity testing. Acknowledgements The following internal reviewers are thanked for their insightful comments: Joseph LiVolsi, Richard McKinney, Wayne Munns, Monique Perron and Jonathan Serbst. Also, our colleagues at the Institute of Hydrobiology (Kyiv, Ukraine) and the Institute of Biology of the Southern Seas (Sevastopol, Ukraine) are thanked for collecting the sediment and tissue samples. This research was funded by the United States Department of State and Environmental Protection Agency Former Bio-Chem Weapons Scientists Re-direct Program administered by the Science and Technology Center of Ukraine (STCU). The authors wish to thank Iryna Tomashevska (STCU) and Doug Steele (US EPA) for their administrative support of this research. This paper is dedicated to the late Bill Freeman (US EPA) for his tireless support of this research and the Re-Direct program. This is NHEERL-AED, Narragansett Contribution AED-06-019. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. This report has been reviewed by the US EPA’s Office of Research and Development National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Agency.

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