Distribution of polychlorinated biphenyls in marine species from French Frigate Shoals, North Pacific Ocean

First assessment of persistent organic pollutants and halogenated natural compounds in an omnivorous resident coral-reef fish species, black triggerfish, Melichthys niger, from an Atlantic oceanic island, Brazil

Studies on the occurrence of POPs and other persistent compounds in pristine areas are extremely valuable, as they offer insights on the long-range transportation of POPs and the occurrence of natural compound producers' areas. In this regard, this study aimed to report data of both anthropogenic (polychlorinated biphenyls, PCBs, and polybrominated diphenyl ethers, PBDEs) and natural (methoxylated PBDEs, MeO-BDEs) compounds in tissues of the black triggerfish, Melichthys niger (Tetraodontiformes, Balistidae), specimens (n = 30) sampled in 2018 during a scientific expedition conducted at Trindade Island. Concentrations of ∑28PCBs ranged from 73 to 1052 ng g-1 lw in liver, 334 to 1981 ng g-1 lw in gonads, and 20 to 257 ng g-1 lw in muscle, with the predominance of PCB-180 in liver and PCB-52 in gonad and muscle. Concentrations of ∑7PBDEs ranged from Collapse

Key Words

• Brazilian island
• MeO-BDEs
• Omnivorous fish
• PBDEs
• Polychlorinated biphenyls
• Trindade Island

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Affiliation(s)

Dhoone Menezes-Sousa Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Micropoluentes Jan Japenga, Av. Carlos Chagas Filho, 373 CCS - Bl. G, Rio de Janeiro, RJ 21941-541, Brazil; Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Radioisótopos Eduardo Penna Franca, Av. Carlos Chagas Filho, 373 CCS - Bl. G, Rio de Janeiro, RJ 21941-541, Brazil.
Marcelo Vianna Universidade Federal do Rio de Janeiro, Instituto de Biologia. Laboratório de Biologia e Tecnologia Pesqueira, Departamento de Biologia Marinha, Av. Carlos Chagas Filho, 373, CCS, Bl. A., Rio de Janeiro, Rio de Janeiro 21941-541, Brazil; IMAM - AquaRio, Rio de Janeiro Aquarium Research Center, Rio de Janeiro, Brazil.
Olaf Malm Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Radioisótopos Eduardo Penna Franca, Av. Carlos Chagas Filho, 373 CCS - Bl. G, Rio de Janeiro, RJ 21941-541, Brazil
João Paulo Machado Torres Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Micropoluentes Jan Japenga, Av. Carlos Chagas Filho, 373 CCS - Bl. G, Rio de Janeiro, RJ 21941-541, Brazil
Mariana Batha Alonso Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Micropoluentes Jan Japenga, Av. Carlos Chagas Filho, 373 CCS - Bl. G, Rio de Janeiro, RJ 21941-541, Brazil

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Organic contaminants in imported salmon feed and their effects on reef ecosystems in New Zealand

Organic matter from salmon farms has been shown to be assimilated by soft sediment and rocky reef communities within the ecological footprint of salmon farms. Given these findings, another question arises - What other chemicals in salmon feed may be assimilated into wild communities via organic waste from salmon farms? Here we measured a suite of organic contaminants in salmon feed, in organisms used in a controlled feeding experiment, and in reef species collected within the depositional footprint of salmon farms. Gas Chromatography-Tandem Mass Spectrometry was used to quantify trace concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and current-use (CPUs) and historic-use pesticides (HUPs) in salmon feed imported to New Zealand. The effect of assimilation of farm-derived organic matter on contaminant profiles differed among species during the controlled feeding experiment and demonstrated that migration of individuals to a farm-associated site has the potential to increase or decrease organic contaminant concentrations. Concentrations of PCBs in Parapercis colias (blue cod), a highly resident, long-lived fish, were significantly higher at farm sites than at reference sites. While these concentrations were relatively low in a global context, this result presents blue cod as an important candidate for future monitoring of organic contaminants around point sources. PCBs and PBDEs measured in wild marine species were all below limits set by the European Union, whereas concentrations of certain HUPs, specifically dichlorodiphenyltrichloroethane (DDT) and its degradation products and endosulfan, may be of concern as a consequence of alternative anthropogenic activities. Overall, feed imported to New Zealand had relatively low levels of most organic contaminants that, at current levels, are unlikely to result in significant ecological effects to wild communities in adjacent habitats.

Organochlorines and Polycyclic Aromatic Hydrocarbons as fingerprint of exposure pathways from marine sediments to biota

To elucidate the dynamics of a suite of organochlorine contaminants (PCBs, HCB), PAHs and Hg and verify the potential of these pollutants as reliable fingerprints of sources, an ensemble of marine sediments and organisms (finfish, shellfish species and Mytilus galloprovincialis) were analysed from the contaminated Augusta Bay (Southern Italy). The Hg and HCB concentration in the sediments exceeded the EQS of the Directive 2000/60/EU. Similarly, ∑PCB and selected PAHs were above the threshold limit set by regulation. The marine organisms showed Hg concentrations above CE 1881/2006. Contaminants in transplanted mussel evidenced an increased accumulation overtime and different distribution patterns between sampling sites. Analysis of the homolog composition of PCB congeners revealed comparable patterns between sediments and marine organisms and offered the opportunity to define a robust fingerprint for tracing contaminants transfer from the abiotic to the biotic compartments. These results were confirmed by the Fluoranthene/Pyrene, Hg and HCB distribution modes.

A potential threat to the coral reef environments: Polybrominated diphenyl ethers and phthalate esters in the corals and their ambient environment (Persian Gulf, Iran)

Pollution of the surrounding habitat poses one of the biggest threats to the coral health and even survival. This study focuses on the occurrence, distribution, bioaccumulation and bioconcentration of polybrominated diphenyl ethers (PBDEs) and phthalate esters (PAEs) in corals, their zooxanthellae and mucus, as well as in their ambient environment in Larak coral reef (Persian Gulf) for the first time. The highest concentrations of the pollutants were recorded in mucus, followed by zooxanthellae, tissue and skeleton. Soft corals with higher lipid content contained more PBDEs and PAEs. Pollutants were both efficiently bioconcentrated from water and bioaccumulated from the ambient sediment, albeit bioconcentration played the most prominent role. Elevated PBDEs and especially PAEs concentrations were detected in the skeletons of the bleached corals if compared to the skeleton samples of the non-bleached individuals.

Chlorinated and brominated persistent compounds in hard coral, soft coral, and parrotfish from remote Mascarene islands

Persistent halogenated compounds (PHC) are of concern for human and environmental health. Persistent Organic Pollutants (POPs) are regulated by international treaties, but alternative compounds such as novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) are not-yet they are increasingly used. There are no data on PHCs in coral reef biota from tropical islands in the western Indian Ocean (WIO). For this assessment, three hard coral genera, two soft coral genera, and ember parrotfish (Scarus rubroviolaceus) were collected from the remote Rodrigues, Agalega, and St. Brandon's Atoll (Republic of Mauritius) in the Mascarene Basin of the WIO. Five compounds - Pentabromotoluene (PBT), γ-HCH, p,p'-DDE, HCB, and BDE-47- were quantifiable in all samples. Hard coral consistently contained the lowest concentrations of PHCs, except for NBFRs. The presence of BDE-47 suggests long-range aerial transport. We quantified DP, currently a candidate POP, in coral reef biota. PBT was measured in all samples also suggests long-range transport. Because the hard coral, soft coral, and fish had differing concentrations and patterns of PHCs, future surveys should stratify sampling accordingly. Agalega and St. Brandon's Atoll can be considered as locations to monitor changes in background concentrations of pollutants due to their remoteness.

Trophic transfer of persistent toxic substances through a coastal food web in Ulsan Bay, South Korea: Application of compound-specific isotope analysis of nitrogen in amino acids

Trophic magnification factor (TMF) of persistent toxic substances (PTSs: Hg, PCBs, PAHs, and styrene oligomers (SOs)) in a coastal food web (12 fish and four invertebrates) was determined in Ulsan Bay, South Korea. The nitrogen stable isotope ratios (δ¹⁵N) of amino acids [δ¹⁵N_Glu-Phe based on glutamic acid (δ¹⁵N_Glu) and phenylalanine (δ¹⁵N_Phe)] were used to estimate the trophic position (TP_Glu-Phe) of organisms. The TP_Glu-Phe of organisms ranged from 1.64 to 3.69, which was lower than TP estimated by δ¹⁵N of bulk particulate organic matter (TP_Bulk: 2.46-4.21). Mercury and CB 138, 153, 187, and 180 were biomagnified through the whole food web (TMF > 1), while other PTSs, such as PAHs and SOs were not (biodilution of SOs firstly reported). In particular, the trophic transfer of PTSs was pronounced in the resident fish (e.g., rock bream, sea perch, Korean rockfish). Of note, CB 99, 101, 118, and 183 were additionally found to be biomagnifying PTSs in these species. Thus, fish residency appears to represent an important factor in determining the TMF of PTSs in the coastal environment. Overall, δ¹⁵N_Glu-Phe provided accurate TPs of organisms and could be applied to determine the trophic transfer of PTSs in coastal food webs.

Tropical seabirds sample broadscale patterns of marine contaminants

Contaminants in the marine environment are widespread, but ship-based sampling routines are much narrower. We evaluated the utility of seabirds, highly-mobile marine predators, as broad samplers of contaminants throughout three tropical ocean regions. Our aim was to fill a knowledge gap in the distributions of, and processes that contribute to, tropical marine contaminants; and explore how species-specific foraging ecologies could inform or bias our understanding of contaminant distributions. Mercury and persistent organic pollutant (POPs) concentrations were measured in adults of five seabird species from four colonies in the central Pacific (Laysan and Tern Islands, Hawaii; Palmyra Atoll) and the eastern Caribbean (Barbuda). Blood-based total mercury (THg) and 89 POPs were measured in two seabird families: surface-foraging frigatebirds (Fregata spp.) and plunge-diving boobies (Sula spp.). Overall, largescale contaminant differences between colonies were more informative of contaminant distributions than inter-specific foraging ecology. Model selection results indicated that proximity to human populations was the best predictor of THg and POPs. Regional differences in contaminants were distinct: Barbudan Magnificent Frigatebirds had more compounds (n=52/89 POP detected) and higher concentrations (geometric mean THg=0.97μgg^-1; mean ΣPOP₅₃=26.6ngmL^-1) than the remote colonies (34-42/89 POP detected; range of THg geometric means=0.33-0.93μgg^-1; range of mean ΣPOP₅₃:7.3-17.0ngmL^-1) and had the most recently-synthesized POPs. Moderate differences in foraging ecologies were somewhat informative of inter-specific differences in contaminant types and concentrations between nearshore and offshore foragers. Across species, contaminant concentrations were higher in frigatebirds (THg=0.87μgg^-1; ΣPOP₅₃=17.5ngmL^-1) compared to boobies (THg=0.48μgg^-1; ΣPOP₅₃=9.8). Ocean currents and contaminants' physiochemical properties provided additional insight into the scales of spatial and temporal contaminant exposure. Seabirds are excellent, broad samplers with which we can understand contaminant distributions in the marine environment. This is especially important for tropical remote regions that are under-sampled.

Antibiotics in corals of the South China Sea: Occurrence, distribution, bioaccumulation, and considerable role of coral mucus

Manmade antibiotics are emerging organic pollutants widely detected in the marine environment. In this study, 14 out of 19 target antibiotics were detected in corals collected from coastal and offshore regions in the South China Sea. The average total antibiotic concentrations (∑₁₉ABs) in the two regions were similar: 28 ng/g for coastal corals and 31 ng/g for offshore corals, based on dry tissue weight (dw). Fluoroquinolones (FQs) were predominant antibiotics in the coastal corals (mean ∑FQs: 18 ng/g dw), while sulfonamides (SAs) predominated in the offshore corals (mean ∑SAs: 23 ng/g dw). However, corals living in coastal regions tend to excrete more mucus than corals in offshore habitat. We found 53% by average of ∑₁₉ABs in the mucus of the coastal corals; while in offshore corals, most antibiotics (88% by average) were accumulated in the tissues. In addition, the tissue-mucus mass distribution differs among individual antibiotics. Sulfonamides were mainly accumulated in tissues while fluoroquinolones were present mainly in mucus. The results of this study suggest that mucus played an important role in the bioaccumulation of antibiotics by corals. It may resist the bioaccumulation of antibiotics by coral tissue, especially for the coastal corals. Additionally, corals were compared with other marine biotas in the study area and found to be more bioaccumulative towards antibiotics.

Distribution of polycyclic aromatic hydrocarbons (PAHs) in commonly consumed seafood from coastal areas of Bangladesh and associated human health implications

Levels, distribution, possible sources and potential risks of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated comprehensively in frequently consumed seafood species collected from the coastal areas of Bangladesh. Samples were collected in winter and summer, 2015. The total concentration of PAHs (∑PAHs) in the examined seafood was 184.5-2806.6 ng/g wet weight (ww) in winter and 117.9-4216.8 ng/g ww in summer, respectively. The levels of ∑PAHs were comparable to or higher than those reported from other coastal areas. Seasonal variation was not significant for the majority of the monitored PAHs. Spatial distribution revealed that the seafood collected from areas with recent urbanization and industrialization (Chittagong, Cox's Bazar and Sundarbans) was more contaminated with PAHs than those from the unindustrialized area (Meghna Estuary). Low-molecular-weight isomers dominated the PAH composition. Molecular ratios suggested the abundance of mixed sources of PAHs in the Bangladeshi coastal areas with a slight imposition toward the petrogenic origin. A preliminary evaluation of human health risk indicated that the dietary PAH exposure from consumption of Bangladeshi seafood would certainly induce adverse health effects. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory in Bangladesh.

Polychlorinated biphenyls (PCBs) in commonly consumed seafood from the coastal area of Bangladesh: occurrence, distribution, and human health implications

Dietary intake is the most important route of polychlorinated biphenyls (PCBs) exposure and seafood is the major dietary component for the coastal populations. It is, therefore, an urgent need to assess the levels of PCBs in seafood. A comprehensive congener-specific evaluation of PCBs was carried out for the first time in Bangladesh. All 209 congeners of PCBs in 48 seafood samples (5 finfish and 2 shellfish species) collected in winter and summer of 2015 were measured by GC-MS/MS. Regardless of season and site, the ∑PCBs (ng/g wet weight) in finfish and shellfish were in the range of 6.4-86.2 and 3.8-37.7, respectively. The results were comparable to or higher than those observed in other studies worldwide, particularly from Spain, China, Korea, Thailand, and Hong Kong. No significant seasonal variation was observed in the levels of ∑PCBs in the examined seafood (p > 0.05); however, interspecies differences were significant (p < 0.05). Nonetheless, spatial distribution revealed seafood collected from the areas with recent urbanization and industrialization (Chittagong, Cox's Bazar, and Sundarbans) were more contaminated with PCBs than the area unaffected by industries (Meghna Estuary). Moderately chlorinated (4-6 Cl) homologs dominated the PCB profiles. The congener profile and homolog composition revealed that the source origin of PCBs in the Bangladeshi seafood was related to mixtures of technical PCBs formulations. The dietary exposure assessment revealed that the coastal residents are sufficiently exposed to the dietary PCBs through seafood consumption which may cause severe health risk including dioxin-like toxic effects.

Persistent organic pollutants in sediments, intertidal crabs, and the threatened Olrog's gull in a northern Patagonia salt marsh, Argentina

Persistent organic pollutants (POPs) are of great concern for the environment. In this study we (a) determine levels and distribution of OCPs, PCBs, and PBDEs in sediments and two crab species (Neohelice granulata and Cyrtograpsus altimanus), (b) assess bioaccumulation in crabs, and (c) explore the occurrence of POPs in the Near Threatened Olrog's gull (Larus atlanticus) chicks and eggs in one of the most important salt marsh environments in the South West Atlantic. Sediments, crabs, and gull chicks and eggs showed POPs presence at low levels; being α-endosulfan, PCB-153, and BDE-47 the most represented compounds. In sediments, pollutant concentrations were lower than those reported in Canadian guidelines for the protection of the aquatic life. POP bioaccumulation was recorded in crabs, suggesting a risk to upper trophic level predators. Further studies are needed to understand the trophic effects of POPs in San Blas bay, particularly on the threatened Olrog's gull.

Occurrence, sources and transport of antibiotics in the surface water of coral reef regions in the South China Sea: Potential risk to coral growth

Laboratory research has indicated that antibiotics had negative effects on coral growth by disturbing natural microbiota; however, no field studies have reported antibiotic contamination levels and their influence on coral growth in natural coral reef regions (CRRs). This study investigated antibiotic occurrence and sources in the surface water from CRRs that have suffered from rapid coral degradation and evaluated their risk to coral growth. These regions are in the South China Sea, including four coastal and two offshore CRRs. The results show that 13 antibiotics were detected in the coastal CRRs with concentrations ranging from 10^-2-10⁰ ng L^-1, while 5 antibiotics occurred in offshore CRRs (300-950 km from the mainland), with concentrations ranging from 10^-2 to 10^-1 ng L^-1. Their concentrations decreased gradually from the coast to offshore in the transport process. However, Yongxing Island, which is approximately 300 km from the mainland, was an exception with relatively higher concentrations than the surrounding reefs because of the ever-increasing human activity on the island. The presence of anthropogenic contaminants antibiotics in CRRs may be a potential risk to coral growth.

Congener-specific levels and patterns of polychlorinated biphenyls in edible fish tissue from the central Red Sea coast of Saudi Arabia

All 209 congeners of polychlorinated biphenyls (PCBs) in edible fish tissue from the central Red Sea coast (Jeddah region) of Saudi Arabia were analyzed by isotope dilution high-resolution gas chromatography-mass spectrometry. The upper-bound total PCB (ΣPCB) levels in nine commonly consumed fish species from three areas were 0.2-82.5ng/g wet weight (17-8450ng/g lipid weight), which were at the lower end of reported global range and far below international tolerance limits (500-3000ng/g ww). Dioxin-like congeners contributed up to 12.8% (mean 6.5%) to ΣPCB in tissue samples, with the total PCB toxic equivalencies (TEQs) at a tolerable range (0.05-2.6pgTEQ/g ww or 2-238pgTEQ/g lw) for all species. PCB profiles were dominated by moderately chlorinated homologs, mainly hexachlorobiphenyls, but less chlorinated congeners were also consistently elevated, notably in Siganus rivulatus (Area III) and Mugil cephalus (Area I). It remains to be ascertained if the latter were breakdown products or due to fresh inputs. The top congeners based on dominance by both occurrence and abundance were identified as potential markers of ΣPCB in fish tissue, which can be used for future selective biomonitoring in case of reasonable constraints on full congener approach.

Assessment of PCB and chlorinated pesticide accumulation in mussels at Kaštela Bay (Eastern Adriatic)

The biological response of mussels Mytilus galloprovincialis, resident and transplanted to cages, to contamination with anthropogenic pollutants from Kaštela Bay, located in the central part of the eastern Adriatic coast, was investigated. The main purpose of this paper is to trace the accumulation of PCBs and chlorinated pesticides (HCB, lindane, heptachlor, aldrin, p,p'-DDTs) as a direct measure of potential contaminant availability to organisms, in a period from 2000 to 2011. In order to do so, cultured mussels (Mytilus galloprovincialis) of the same size and age were transplanted from the unpolluted Mali Ston Bay to the Kaštela Bay. Sampling was performed bimonthly, and the level of target contaminants in whole soft tissue was determined. After two months of exposure, the concentration of PCBs in transplanted mussels increased on average 6.5-times, and of DDTs 2-times, while the intensity of changes for HCB, lindane, heptachlor and aldrin was negligible. Seasonal variation of pesticide content was similar without a significant change throughout the experimental period, while that of PCBs was somewhat different showing increased accumulation in summer. Seasonal and spatial variation of organochlorines in the Kaštela Bay was likely the result of prevailing environmental rather than biological parameters. In accordance with prevailing hydrodynamic cycling, contaminant concentration decreased in acyclonic direction towards the exit of the Bay. Measurement of target contaminants in resident mussels sampled from the most contaminated area of the Bay exhibited decreasing concentrations of lindane, aldrin and p,p'-DDTs. However, PCBs exhibited statistically significant increasing concentrations in relation to the slightly increasing concentrations of HCB. With regard to human health, organochlorine (OC) levels in the mussel tissue were below prescribed limits for human consumption.

The flip-or-flop boutique: Marine debris on the shores of St Brandon's rock, an isolated tropical atoll in the Indian Ocean

Isolated coral atolls are not immune from marine debris accumulation. We identified Southeast Asia, the Indian sub-continent, and the countries on the Arabian Sea as most probable source areas of 50 000 items on the shores of St. Brandon's Rock (SBR), Indian Ocean. 79% of the debris was plastics. Flip-flops, energy drink bottles, and compact fluorescent lights (CFLs) were notable item types. The density of debris (0.74 m(-)(1) shore length) is comparable to similar islands but less than mainland sites. Intact CFLs suggests product-facilitated long-range transport of mercury. We suspect that aggregated marine debris, scavenged by the islands from currents and gyres, could re-concentrate pollutants. SBR islets accumulated debris types in different proportions suggesting that many factors act variably on different debris types. Regular cleaning of selected islets will take care of most of the accumulated debris and may improve the ecology and tourism potential. However, arrangements and logistics require more study.

Polychlorinated Biphenyls in the Plasma and Preen Oil of Black-Footed Albatross (Diomedea nigripes) Chicks and Adults on Midway Atoll, North Pacific Ocean

Polychlorinated biphenyls (PCBs) are ubiquitous in the environment. Midway Atoll, located in the North Pacific Ocean, was occupied by the military during and after World War II. However, Midway Atoll has become a national wildlife refuge and home to many different seabirds today, including the black-footed albatross (Diomedea nigripes) (BFAL). The profiles and toxic equivalents (TEQ) of PCB congeners in the plasma and preen oil of BFAL chicks and adults were determined in this study. The concentrations of the total PCBs in the plasma samples of chicks and adults collected in Midway Atoll ranged from 2.3 to 223.8 (mean 80.1) and 22.8 to 504.5 (mean 158.6) ng g(-1) (wet weight, ww), respectively. The TEQs ranged from 0.2 to 0.6 (mean 0.4) and 0.4 to 1.6 (mean 0.9) pg g(-1) ww, respectively, in the plasma samples of chicks and adults from Midway Atoll. The major congeners in the plasma samples of chicks and adults included PCBs 31, 87, 97, 99, 118, 138, 153, and 180, accounting for 70% of the total PCBs. The concentrations of the total PCBs in the adult preen oil samples ranged from 1693 to 39404 (mean 10122) ng g(-1) (ww), of which 97% were PCBs 105, 118, 128, 138, 153, 161, 172, and 183.

Aroclor 1254 inhibits the chemiluminescence response of peritoneal cavity cells from sharpsnout sea bream (Diplodus puntazzo)

Chronic exposure to polychlorinated biphenyls (PCBs) affect the immune system of fish and could lead to a decreased disease resistance. The effects of Aroclor 1254, PCB mixtures, on the Diplodus puntazzo innate immunity were examined by assaying the zymosan stimulated chemiluminescence response (CL) of peritoneal cavity cells (PCCs) at various times (1, 24, 48 h and 1-4 weeks) from intraperitoneal injection of the xenobiotic (1 mg kg(-1) body weight). Controls were performed by assaying cells from medium-treated fish. Since the kinetic of the chemiluminescence response showed the highest peak at 25 min after the zymosan stimulation of the cells, the values found at that time were considered. The CL enhancement observed at 1 h after the treatment with xenobiotic was followed by a decreased response at 24 h and appeared to be lower at 1-4 weeks when compared to the CL response of the control, suggesting a protracted effect of PCBs on the peritoneal cavity. Since PCCs incubated in vitro for 1 h with 0.05 and 0.1 μg ml(-1) Aroclor showed an enhanced CL, the effect of the xenobiotic could be exerted on the cell responsiveness to zymosan. It is known that fish CL response of PCCs can be imputed to phagocyte (macrophages and neutrophils) activation, these cells and their responsiveness to zymosan can be used in immunotoxicology assay to monitor the fish health in polluted environment.

Comparative study of polycyclic aromatic hydrocarbons in coral tissues and the ambient sediments from Kenting National Park, Taiwan

Surface sediments and corals (Acropora sp. and Montipora sp.) from the coastline of Kenting were analyzed in 2009 and 2010 for content levels of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry. The total PAH concentrations (t-PAH) in corasls (143-1715 ng g(-1) dw) were significantly higher than in the ambient sediments (2-59 ng g(-1) dw) indicating the bioaccumulation of PAHs in corals. The spatial and seasonal variation in PAH levels suggested that land-loaded contaminants may be the main source of PAHs in the Kenting coral reefs. Based on molecular indices, PAHs were substantially of petroleum origin. The major PAH components were phenanthrene, pyrene and fluorine, but PAH congeners in corals and sediments still have characteristic composition patterns which would be altered by the bio/accumulation mechanisms. Further study is essential to assess and understand the impacts of these chemicals on coral reefs.

Concentrations, source and risk assessment of polycyclic aromatic hydrocarbons in soils from midway atoll, north pacific ocean

This study was designed to determine concentrations of polycyclic aromatic hydrocarbons (PAHs) in soil samples collected from Midway Atoll and evaluate their potential risks to human health. The total concentrations of 16 PAHs ranged from 3.55 to 3200 µg kg(-1) with a mean concentration of 198 µg kg(-1). Higher molecular weight PAHs (4-6 ring PAHs) dominated the PAH profiles, accounting for 83.3% of total PAH mass. PAH diagnostic ratio analysis indicated that primary sources of PAHs in Midway Atoll could be combustion. The benzo[a]pyrene equivalent concentration (BaPeq) in most of the study area (86.5%) was less than 40 µg kg(-1) BaPeq and total incremental lifetime cancer risks of PAHs ranged from 1.00×10(-10) to 9.20×10(-6) with a median value of 1.24×10(-7), indicating a minor carcinogenic risk of PAHs in Midway Atoll.

Persistent organic pollutants (PCBs and DDTs) in European conger eel, Conger conger L., from the Ionian Sea (Mediterranean Sea)

The present study provides novel data regarding levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (DDTs) in muscle tissue of European conger eel (Conger conger) from Ionian Sea (Mediterranean Sea). The mean concentration of PCBs (891 ng g(-1) lipid weight) was higher than those of DDTs (543 ng g(-1) lipid weight). PCB pattern was dominated by higher chlorinated congeners (hexa-CBs: 69.3 %, penta-CBs: 17.2 %, hepta-CBs: 13.3 %). Regarding DDT pattern, p,p'-DDE was prevalent in all samples (85.5 %), suggesting no recent DDT input. The total 2,3,7,8-TCDD toxic equivalent (TEQs) of coplanar PCBs, including mono-and non-ortho congeners was 0.41 pg g(-1) wet weight (29.92 pg g(-1) lipid weight). The PCB and DDT levels, as well as TEQ concentrations were lower than most of the corresponding published data for fish from Mediterranean and non-Mediterranean regions, probably reflecting a moderately contaminated area.

Assessing the effects of polychlorinated biphenyls (Aroclor 1254) on a scleractinian coral (Stylophora pistillata) at organism, physiological, and molecular levels

Polychlorinated biphenyls (PCBs) are a group of widespread contaminants, and accumulation of PCBs has been observed in corals in the field. However, the toxic effects of PCBs on corals have not been investigated. In this study, we tested short and long term toxicity of Aroclor 1254, a commercial PCB mixture, on the scleractinian coral Stylophora pistillata. Coral nubbins were incubated in either control seawater or seawater dosed with PCBs (approximately 300ng/L) for 96h. The effect of PCB exposure on coral gene expression at 4h post exposure was tested with the suppression subtractive hybridization (SSH) and quantitative PCR methods. Photosystem II activity of the zooxanthellae was measured at 96h. After the exposure, nubbins were moved into clean seawater and their survival and growth were observed for another 50 days. All nubbins survived during the exposure and the following 50-d recovery period. Photosystem II activity and coral growth were not affected by PCB exposure in this study. Fifty-four clones were sequenced for gene expression analysis, and 15% of these sequences were identified, including genes involved in general stress response, peptide metabolism, cellular receptor, cytoskeleton organization, membrane trafficking, and oxidative stress response. However, the quantitative PCR did not show significant difference in the five selected genes. In conclusion, acute exposure of S. pistillata to Aroclor 1254 at 300ng/L did not affect coral survival, photosynthesis or growth but may alter the expression of certain genes involved in various important cellular functions. The nubbin technique proved to be an efficient approach to simultaneously characterize the impact of PCBs on the corals at multiple biological levels.

Environmental contamination of ready meals by polychlorinated biphenyls (PCBs)

The level of polychlorinated biphenyls (PCBs) contamination in ready meals was investigated to determine exposure compared to other foodstuffs. Chilled ready meals from nine categories (ambient, Chinese, Indian, Traditional UK, Italian, American Tex-Mex, Vegetarian and Organic), and three samples within each category were Soxhlet extracted in triplicate with hexane for 24 h, followed by a clean-up on deactivated silica gel. The cleaned extracts were concentrated to 1 ml under N(2) gas and analyzed on gas chromatography mass spectrometry (GC-MS) for 7 target PCBs (congeners 28, 52, 101, 118, 153, 138, and 180). Individual congener concentrations ranged from non-detectable to 0.40 ng g(-1) (wet weight). The cumulative concentration of all congeners (ΣPCBs) ranged between 0.20 and 1.00 ng g(-1) (wet weight). These values translate into exposure levels of less than 1 μg kg(-1)day(-1) for reference men and women of 70 and 57 kg, respectively. This preliminary study demonstrates that ready meals, like many other foods, are contaminated by PCBs and may represent an important route of human exposure given contemporary changes in consumer food choice. Even though low levels of contamination were observed, long-term exposure for population groups consuming a high volume of ready meals may have cause for concern regarding chronic health risks.

Spatial distribution of organochlorine contaminants in soil, sediment, and fish in Bikini and Enewetak Atolls of the Marshall Islands, Pacific Ocean

Several nuclear tests were performed at Enewetak and Bikini Atolls in the Marshall Islands between 1946 and 1958. The events at Bikini Atoll involved several ships that were tested for durability during nuclear explosions, and 24 vessels now rest on the bottom of the Bikini lagoon. Nine soil samples were collected from different areas on the two islands of the atoll, and eighteen sediment, nine fish, and one lobster were collected in the vicinity of the sunken ships. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polychlorinated terphenyls (PCTs) in these samples were analyzed using gas chromatography/ion trap mass spectrometry (GC/ITMS). The average recoveries ranged from 78% to 104% for the different PCB congeners. The limits of detection (LOD) for PCBs, PCTs, DDE, DDT, and dieldrin ranged 10-50 pg g(-1). Some fish from Enewetak contained PCBs at a concentration range of 37-137 ng g(-1), dry weight (dw), and most of the soils from Enewetak showed evidence of PCBs (22-392 ng g(-1)dw). Most of the Bikini lagoon sediment samples contained PCBs, and the highest was the one collected from around the Saratoga, an aircraft carrier (1555 ng g(-1)dw). Some of the fish samples, most of the soil samples, and only one of the sediment samples contained 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE) and PCBs. In addition to PCBs, the soils from Enewetak Atoll contained PCTs. PCTs were not detected in the sediment samples from Bikini Atoll. The results suggest local pollution sources of PCBs, PCTs, and OCPs.

Concentration of DL-PCBs in fish from market of Parma city (north Italy): estimated human intake

The concentrations of 12 congeners of non-ortho and mono-ortho dioxin-like polychlorinated biphenyls (ΣDL-PCB) were measured in 30 fish samples from Parma markets by GC/MS technique. The samples were randomly purchased, choosing the species commonly found in supermarkets. The concentration of DL-PCBs estimated remained under the fixed Italian limit of 4 pg g(-1)ww WHO-TEQ (World Health Organization-Toxic Equivalent) in the major part of the samples, so the situation seems to be not at a level sufficient to pose a risk to human health of the Parma population. The medium daily intake for DL-PCBs for Italian consumers (Parma) was also estimated. This value generally resulted minor than 2 pg g(-1) ww WHO-TEQ kg(-1) body weight, exceeding only in four cases: eel, smooth hound, starry smooth hound and tuna.

Accumulation and maternal transfer of polychlorinated biphenyls in Steller Sea Lions (Eumetopias jubatus) from Prince William Sound and the Bering Sea, Alaska

The western stock of the Steller sea lion (Eumetopias jubatus) in the northern Pacific Ocean has declined by approximately 80% over the past 30 years. This led to the listing of this sea lion population as an endangered species in 1997. Chemical pollution is [corrected] one of several contributing causes. In the present study, 145 individual PCBs were determined in tissues of male sea lions from Tatitlek (Prince William Sound) and St. Paul Island (Bering Sea), and placentae from the Aleutian Islands. PCBs 90/101, 118, and 153 were abundant in all the samples. The mean toxic equivalents (TEQ) were 2.6, 4.7 and 7.4 pg/g lw in the kidney, liver, and blubber samples, respectively. The mean TEQ in placentae was 8 pg/g lw. Total PCBs concentrations (2.6-7.9 μg/g lw) in livers of some males were within a range known to cause physiological effects, further [corrected] suggesting the possibility of adverse effects on this stock.

Molecular toxicology of corals: a review

Coral reefs worldwide have become increasingly affected by a phenomenon known as "coral bleaching," the loss of the symbiotic algae from the host corals. The underlying causes and mechanism(s) of coral bleaching are not well known, although several have been hypothesized. While coral bleaching has been a primary focus in recent years, corals respond differentially to numerous environmental stresses. The impacts of heat, hydrocarbons, salinity, sewage effluents, biocides, heavy metals, and ultraviolet light have been investigated in both laboratory experiments and field surveys among multiple coral species. Herein what is known regarding the biological impacts of such stresses on corals at the molecular level of organization is summarized. The objective is to focus attention at the early stages of biological effects in order to encourage and facilitate research that provide ways to understand how changes at the molecular level might elucidate processes likely occurring at the population level. This, in turn, should accelerate studies that may elucidate the cellular and physiological changes contributing to coral decline, rather than just document the continued global loss of coral diversity and abundance.

Tissue distribution of polychlorinated biphenyls and organochlorine pesticides and potential toxicity to Alaskan northern fur seals assessed using PCBs congener specific mode of action schemes

The fur seal (Callorhinus ursinus) population has decreased in their primary breeding grounds in the Bering Sea; contamination is among suspected causes. Our goal was to better understand the extent of contamination of seal tissues with certain organochlorine compounds by measuring the concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in fur seal tissues from St. Paul Island, to gain a better perspective of tissue congener distribution and to evaluate the observed PCB levels against toxicologically significant levels for modes of action. Concentrations of 145 PCB congeners (Sigma(145)PCBs) and 12 OCPs were measured with gas chromatography-ion trap mass spectrometry in 8 different tissues of 10 male northern fur seals. The mean concentrations of SigmaOCPs [in ng/g lipid weight (lw)] were 1180 in blubber, 985 in the heart, 1007 in the liver, 817 in the kidney, 941 in muscle, 660 in reproductive tissues, 204 in the brain, and 322 in the lung. The mean concentrations of Sigma(145)PCBs (in ng/g lw) were 823 in blubber, 777 in the liver, 732 in the heart, 646 in reproductive tissues, 638 in muscle, 587 in the kidney, 128 in the lung, and 74.3 in brain tissues. Concentrations of PCBs affecting the aryl hydrocarbon receptor expressed as total PCB toxic equivalents (SigmaPCB-TEQs) ranged from 0.3 to 545 pg/g lw for the various tissues. The major contributors to SigmaPCB-TEQs are CB-118 in muscle, brain, lung, kidney, and liver, CB-126 in blubber, and CB-118 and CB-126 equally in the heart and reproductive tissues. Concentrations of PCBs affecting Ca(2+) homeostatsis expressed as the neurotoxic equivalent (NEQ) showed SigmaPCB-NEQs ranged from 17.7 to 215 ng/g lw in all tissues. Although no composite measure of perturbation of thyroid function is available, sufficient amounts of congeners with high binding to the thyroxine transport system were present to warrant consideration of this mode of action in future studies. Analyses of 145 PCBs and mode of action evaluation suggest that PCB contamination could potentially exert an effect on the Alaskan northern fur seal population although the PCB concentrations have been decreasing in the fur seals over the last decade.

Monitoring of polychlorinated biphenyl contamination and estrogenic activity in water, commercial feed and farmed seafood

We evaluated the concentration and congener distribution of seven "target" polychlorinated biphenyls (PCBs) present in water collected in different aquaculture farms of the Mediterranean area, commercial feeds, and farmed seafood. PCBs were present in feed and in tissues of all the analysed organisms at levels ranging from 1.96 ng g(-1) to 124.00 ng g(-1) wet weight, and in 10.5% of the water samples, at levels from under detection limit to 33.0 ng l(-1) with total PCB concentrations significantly higher in samples from the Tyrrhenian Sea than the Adriatic Sea. PCB congener distribution in tissues resembled that of feed, suggesting that commercial feed is an important source of PCBs. The estrogenicity of organic extracts of the samples was also evaluated by using an in vitro yeast reporter assay. Estrogenic activity higher than 10% of the activity induced by 10 nM 17 beta-estradiol was observed in 20.0% of seafood samples and 15.8% of water samples. Seafood and water samples from the Tyrrhenian Sea were more frequently estrogenic than the Adriatic ones (16.45 versus 4.08%). A significant correlation of total PCB concentrations on biological activity was observed for sea bass and mussels from the Adriatic Sea (p < 0.045 and p < 0.04, respectively), and for sea bass of the Tyrrhenian Sea (p = 0.05). These results indicate the need of an integral approach in the exposure assessment to potential toxic compounds for human via food.

Detection and quantitative analysis of polychlorinated biphenyls in tilapia from Hawaiian waters

The purpose of this study was to investigate polychlorinated biphenyls (PCBs) contamination in tilapia (Oreochromis mossambicus) collected from the Manoa stream and Ala Wai Canal of O'ahu, an island of the geographically isolated Hawaiian archipelago. Our results show that the average concentrations of PCBs varied from 51.90 to 89.42 ng g(-1) lipid weight for the sampling sites. Relative toxic potencies (RTPs) and toxic equivalencies (TEQs) were determined to be 20.38-40.60 ng TCDDg(-1) lipid weight and 2.89-4.17 ng TEQ g(-1) lipid weight by 7-ethoxy-resorufin-O-deethylase (EROD) activity analysis and calculation of PCB concentrations based on toxic equivalency factors (TEFs), respectively. Penta-chlorinated congeners were found to be predominant, which revealed that Aroclor 1254 was a possible major source of PCBs in our fish samples. PCB 118, an indicator PCBs, constituted more than 55% and 30% of the total PCBs and TEQs, respectively. In addition, PCB 118 was found to have a linear correlation to the total PCBs (R=0.975) and TEQs (R=0.782). Detection of concentrated PCBs in Hawaiian waters suggests a potentially adverse impact of this pollutant on human health, as well as ecological systems, and suggests the necessity of environmental monitoring and hazard assessment of PCBs within the Hawaiian Islands.

Organochlorine contaminants in endangered Hawaiian monk seals from four subpopulations in the Northwestern Hawaiian Islands

We analyzed blubber and blood samples for organochlorines (OCs) from 158 Hawaiian monk seals (Monachus schauinslandi) at four of their six primary breeding colonies in the Northwestern Hawaiian Islands. Levels of OCs in blubber were lower in adult females compared to juveniles or adult males, evidently owing to the transfer of these lipophilic compounds to pups by pregnant and lactating females. Concentrations of SigmaPCBs and p,p'-DDE in blubber generally increased with age until seals were sexually mature and then continued to increase with age in males after puberty. Average levels of PCBs and PCB toxic equivalents (TEQs) in blubber were significantly higher in adult male and juvenile seals at Midway Atoll than the same age class of seals at the other colonies. Unlike concentrations of OCs in blubber, circulating levels of OCs in blood did not vary consistently among age classes of seals or among breeding colonies. Though the concentrations of OCs measured in Hawaiian monk seals were generally equal to or lower than those reported for other pinniped species in the North Pacific Ocean, they were high enough in a few seals to potentially affect their health.

Analysis of organochlorine pesticides in coral (Porites evermanni) samples using accelerated solvent extraction and gas chromatography/ion trap mass spectrometry

A gas chromatography/ion trap mass spectrometry method was developed for analysis of organochlorine pesticides (OCPs) in coral samples, which were extracted with accelerated solvent extraction (ASE) and cleaned up on a sulfuric acid-modified silica gel column. The optimal ASE conditions were found to be 100 degrees C and 2000 psi, with a mixture of acetone and methylene chloride (1:1, v/v). The target analytes include hexachlorocyclohexanes (HCHs, specifically, alpha-, beta-, gamma-, and delta-HCH isomers), heptachlor, and hexachlorobenzene (HCB), o,p'-, p,p'-dichlorodiphenyltrichloroethane (o,p'-, p,p'-DDT), o,p'-, p,p'-dichlorodiphenyl-dichloroethylene (o,p'-, p,p'-DDE), and o,p'-, p,p'-dichlorodiphenyldichloroethane (o,p'-, p,p'-DDD). Standard sand samples were used as an alternative matrix spiked with OCP standards to determine the method precision and accuracy. Average recoveries of OCPs ranged from 82% to 102%, with relative standard deviations (RSDs) of 3%-6%, at a level of 10 ng/g and from 50% to 68%, with RSDs of 13%-19% at a level of 2 ng/g. The developed method was applied for analysis of OCPs in coral samples collected from Tern Island and Bikini Atoll in the Pacific Ocean. The concentrations of HCB were 7-26 pg/g dry weight in the samples from Bikini Atoll and 3-45 pg/g in those from Tern Island, and heptachlor concentrations were 208-2200 and 44-104 pg/g in the coral samples from Bikini Atoll and Tern Island, respectively. (summation operator)HCH (sum of alpha-, beta-, gamma-, and delta-HCH) were 8-82 pg/g in Bikini Atoll coral and 86-629 pg/g in Tern island coral, and (summation operator)DDT (sum of o,p'-, p,p'-DDD, o,p'-, p,p'-DDE, and o,p'- p,p'-DDT) were 80-212 pg/g in Bikini Atoll coral and 593-3165 pg/g in Tern Island coral. The results suggest that coral is a viable indicator species for pollution monitoring, which pollutants and their concentrations may be related to dated carbonate layers.

Persistent organic pollutants carried by synthetic polymers in the ocean environment

Thermoplastic resin pellets are melted and formed into an enormous number of inexpensive consumer goods, many of which are discarded after a relatively short period of use, dropped haphazardly onto watersheds and then make their way to the ocean where some get ingested by marine life. In 2003 and 2004 pre-production thermoplastic resin pellets and post-consumer plastic fragments were collected and analyzed for contamination for persistent organic pollutants (POPs). Samples were taken from the North Pacific Gyre, and selected sites in California, Hawaii, and from Guadalupe Island, Mexico. The total concentration of PCBs ranged from 27 to 980 ng/g; DDTs from 22 to 7100 ng/g and PAHs from 39 to 1200 ng/g, and aliphatic hydrocarbons from 1.1 to 8600 microg/g. Analytical methods were developed to extract, concentrate and identify POPs that may have accumulated on plastic fragments and plastic pellets. The results of this study confirm that plastic debris is a trap for POPs.

Organochlorinated contaminants in decapod crustaceans from the coasts of Brittany and Normandy (France)

The contamination and distribution of organochlorinated compounds were considered in three crustacean species (edible crab, Cancer pagurus; spider crab, Maja brachydactyla; velvet swimming crab, Necora puber) from five sites along the coasts of Brittany and Normandy (Western and North-Western France). PCBs (16 single congeners), pp'-DDE and HCB were measured in hepatopancreas, gonads and muscle: in all, 175 samples were analysed. The spider crab was the only species found in the five sampling sites, thus enabling comparison between areas. Specimens from Antifer were much more contaminated (summation operator 16 PCBs in hepatopancreas=2000-4000 ng g(-1) dry weight) than those from other sites (50-1000 ng g(-1) d.w.). Among all the three species, the spider crab appeared more contaminated by PCBs than the edible crab, by a factor 2-3, probably in relation with specific differences in their life cycle. There was no difference due to the gender of the species. Within the different analysed tissues, contamination levels increased from muscle to gonads and hepatopancreas in relation with the fat content. A very similar PCB composition was observed in all samples, PCB fingerprints being characterised by the relative importance of the more persistent PCB congeners: CB153, 138, 180, 187, and 118. Finally, these results were compared to recent food regulations first of maximum marker PCB intake and secondly of maximum dioxin-like PCB intake. By considering the muscle, all samples were far below the regulatory limits; for hepatopancreas and gonads, however, some samples were unfit for human consumption.

PCB levels in European eel (Anguilla anguilla) from two coastal lagoons of the Mediterranean

Eels are exposed to pollutants due to their unusual life cycle and are vulnerable to contamination associated with sediment due to their diet, feeding habits and territoriality. Since the 1980s, a decline in American and European eel populations has been recorded. The causes of this decline still are unknown but pollution from domestic and industrial effluents is known to be involved. Since little data is available on PCB contamination in eels from Italian waters, PCBs were measured in muscle of Anguilla anguilla captured in 2001 in two brackish ecosystems of the Mediterranean: the lagoons of Orbetello and Santa Giusta (Italy). PCBs were higher in samples from Orbetello lagoon than in those detected from Santa Giusta lagoon (P < 0.05). Congener and isomer analyses indicated Aroclor 1260 as a likely source of PCBs in the Orbetello and Santa Giusta samples. Only the toxic equivalents (TEQs) of mono-ortho PCBs were calculated.

Estrogen-like activity of seafood related to environmental chemical contaminants

BACKGROUND

A wide variety of environmental pollutants occur in surface waters, including estuarine and marine waters. Many of these contaminants are recognised as endocrine disrupting chemicals (EDCs) which can adversely affect the male and female reproductive system by binding the estrogen receptor and exhibiting hormone-like activities. In this study the estrogenic activity of extracts of edible marine organisms for human consumption from the Mediterranean Sea was assayed.

METHODS

Marine organisms were collected in two different areas of the Mediterranean Sea. The estrogenic activity of tissues was assessed using an in vitro yeast reporter gene assay (S. cerevisiae RMY 326 ER-ERE). Concentrations of polychlorinated biphenyls (PCBs) (congeners 28, 52, 101, 118, 138, 153, 180) in fish tissue was also evaluated.

RESULTS

Thirty-eight percent of extracts showed a hormone-like activity higher than 10% of the activity elicited by 10 nM 17b-estradiol (E2) used as control. Total PCB concentrations ranged from 0.002 up to 1.785 ng/g wet weight. Chemical analyses detected different levels of contamination among the species collected in the two areas, with the ones collected in the Adriatic Sea showing concentrations significantly higher than those collected in the Tyrrhenian Sea (p < 0.01).

CONCLUSION

The more frequent combination of chemicals in the samples that showed higher estrogenic activity was PCB 28, PCB 101, PCB 153, PCB 180. The content of PCBs and estrogenic activity did not reveal any significant correlation.

Distribution of polychlorinated biphenyls in the water, sediment and fish from the Pearl River estuary, China

The concentrations and distribution of polychlorinated biphenyls were determined in water, surface sediments and fishes from the estuaries of Pearl River, PR China. The results showed that the concentrations ranged from 2.47 ng l-1 to 6.75 ng l-1 in water, from 11.13 ng g-1 to 23.23 ng g-1 in sediments (dry weight) and from 68.64 ng g-1 to 316.85 ng-1 in fish (lipid weight). It was found that the feeding habits of fish were very significant in the accumulation of polychlorinated biphenyls and pattern of congeners. Carnivorous and benthic fishes such as eel (Anguilla japonica) and Chinese sea catfish (Arius sinensis) were found to have high concentrations of polychlorinated biphenyls and of high-chlorinated congeners, while herbivores such as shad (Clupanodon punctatus) and mullet (Mugil cephalus) exhibited an opposite trend. Congeners IUPAC Nos. 153, 138, 118, 87/81, 170 and 52 were found frequently in most samples (both sediment and fish). In comparison with other places in the world, the concentration of polychlorinated biphenyls in sediment and fish from the estuary of Pearl River were low.

Persistent organic pollutants and heavy metals in typical seafoods consumed in Singapore

In this study, the levels of several heavy metals and persistent organic pollutants (POPs) were measured in the edible portions of 20 different seafood types consumed in Singapore (2 < n < 12). The mean heavy metal concentrations among the seafood types ranged from below detection limits (BLD) to 14.2 microg/g wet weight (ww) for As (shark), to 0.50 microg/g ww for Cd (kunning), to 25.5 microg/g ww for Cu (gray prawn), to 0.58 microg/g ww for Hg (eel), and to 1.21 microg/g ww for Pb (salmon). Chlordane, polychlorinated biphenyls (PCBs), and p, p'-DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] and its related metabolites (sum noted as DDTs) were the main POPs found among the seafood types, with highest concentrations in salmon fillets and green mussels. Polybrominated diphenyl ether (PBDE) concentrations in salmon fillets (2.75 ng/g ww) were one order of magnitude lower than the highest concentration of PCBs (28.5 ng/g ww). The mean daily intake of contaminants from seafood was calculated for the general population of Singapore. Daily intakes of heavy metals and POPs from seafood are below the oral reference dose set by the U.S. Food and Drug Administration (FDA), except for As, although our study did not characterize the species of As present. Daily intake of As, DDTs, heptachlor, and PCBs in seafood exceeded the conservative cancer benchmark concentrations set by the U.S. Environmental Protection Agency (EPA), suggesting that a significant number of people are potentially at risk in Singapore over a lifetime from seafood consumption.

Organochlorines in the free-ranging Hawaiian monk seal (Monachus schauinslandi) from French Frigate Shoals, North Pacific Ocean

The Hawaiian monk seal (Monachus schauinslandi) is an endangered species found only in the Hawaiian Island chain. The largest subpopulation, at French Frigate Shoals, has been in decline since 1989. In order to assess organochlorine (OC) levels in the Hawaiian monk seals, whole blood and blubber samples were collected in 1999 from 46 free-ranging Hawaiian monk seals at French Frigate Shoals, and were analyzed for eight dioxin-like polychlorinated biphenyls (PCBs) as well as six other PCB congeners, DDT and DDT metabolites. Average levels of the total PCBs in blood samples from adult male, juvenile and reproductive female groups were 4800, 4000 and 3000 ng/g lipid wt., respectively, whereas 3200, 1300 and 1200 ng/g, respectively, in blubber from the three corresponding groups. p,p'-DDE was the only DDT detected in blubber samples, and no DDTs were detected in blood samples. Concentrations of the total PCBs in adult males were significantly higher than the levels measured in either reproductive females or juveniles. There were significant correlations between age and blubber p,p'-DDE, estimated mass and total blood PCBs or blubber p,p'-DDE, and body condition and total blood PCBs. Although it is clear that the Hawaiian monk seal has been exposed to OCs, it is unclear what biological effects, if any, these xenobiotics may have on the animals.

Relationships between persistent organic chemicals residues and biochemical constituents in fish from a protected area: the French National Nature Reserve of Camargue

The Reserve of Biosphere of Camargue [French National Nature Reserve of Camargue (NNRC)] is a protected area frequently exposed to natural and anthropogenic environmental alterations. To evaluate potential contamination of fish with lipophilic chemicals-organochlorines (OCs) and polycyclic aromatic hydrocarbons (PAHs)-a biological monitoring survey was carried out. Metabolic reserve levels were evaluated to select appropriate biological indicators able to be significant biomarkers. In addition, the incorporation of xenobiotic molecules in the lipid compartments was investigated. The contents of glycogen, total lipids, proteins and lipidic phosphorus were analyzed in liver and skeletal muscles of three teleostean: the European eel (Anguilla anguilla); the crucian carp (Carassius auratus); and the catfish (Ictalurus melas). The atmospheric origin of the PAH detected in any season in the biomass and the OCs compounds contamination by derive from agricultural treatments are established. In contradiction with some laboratory acute intoxication studies, we observe a positive correlation between tissue concentrations of contaminants and the muscular glycogen amount, a sensitive energy reserve marker. Moreover, it seems likely that the incorporation of these xenobiotics is located preferentially in the membrane structures.

Congener-specific profile and toxicity assessment of PCBs in green turtles (Chelonia mydas) from the Hawaiian Islands

Chemical pollution may play a role in the etiology of fibropapillomatosis in green turtles (Chelonia mydas). In this preliminary study, polychlorinated biphenyls (PCBs) were measured in the livers and adipose fats of green turtles collected after they were stranded on Oahu Island, Hawaii in 1992-1993. Average concentrations of total PCBs were 45-58 ng/g dry weight and 73-665 ng/g in the liver and adipose tissues, respectively. Hexachlorobiphenyls were predominant homologues, PCBs 153 and 138 were dominant congeners in all the turtle tissues. Among the most toxic coplanar congeners, in the order of abundance, were PCB 77 > 126 > 169. Estimated toxic equivalents (TEQs) of PCBs to 2,3,7,8-tetrachlorodibenzo-p-dioxin were 8-15 pg/g in the livers and 13-48 pg/g in the adipose tissues. PCB 126 contributed 85-91% of the total TEQs.

Comparative concentrations of metals in marine species from French Frigate Shoals, North Pacific Ocean

Concentrations of arsenic, cadmium, chromium, copper, lead, mercury, selenium, and zinc were measured in coral, crab, eel, fish, lobster, and sediment samples collected from French Frigate Shoals, North Pacific Ocean. The sediments contained relatively high concentrations of selenium; moderate concentrations of arsenic, cadmium, copper and lead; and low concentrations of chromium and zinc. Metal concentrations were also determined in coral and crabs collected from the island of Oahu. Notably, a crab (Grapsus tenuicrustatus) and the undulated moray eel (Gymnothorax undulatus) exhibited high levels of copper and arsenic, respectively, relative to the other species studied. The concentrations of arsenic in the eel averaged 225 microg g(-1) dry wt, which was 3-12 times higher than that in all of the other species tested. The average concentration of copper in the crab was 343 microg g(-1) dry wt, 3-86 times greater than that in the other species studied. These data indicate background and comparative levels of the metals among the studied species. Lead levels in the coral (9-10 microg g(-1) dry wt) and crab (42-57 microg g(-1) dry wt) from Tern and Disappearing Islands were 23-283-fold greater than those from Oahu (0.4 and 0.2 microg g(-1) dry wt, respectively).