Persistent organochlorine concentrations in sediment and fish from Atlantic coastal and brackish waters off Savannah, Georgia, USA

Micro-organic pollutants and biological response of mussels in marinas and ship building/breaking yards in Turkey

Concentrations of PAHs, PCBs and OCPs in sediments and mussels (caged and/or native) were determined at 16 stations in six major sites of coastal Turkey. The biological effects of pollution were evaluated using sediment toxicity tests and enzyme activity assays. EROD, PROD, GST, AChE, CaE, and GR activities were evaluated using the digestive glands of mussels. The total PAH concentrations in the sediments varied between nd and 79,674 ng g(-1) dw, while the total OCP concentrations were in the range of nd to 53.7 ng g(-1) dw. The total PAH concentrations in mussels varied between 22.3 and 37.4 ng g(-1) ww. The average concentrations of total PCBs in mussels were 2795 pg g(-1) ww in the shipyard, 797 pg g(-1) ww in Marina 2 and 53 pg g(-1) ww in Marina 1 stations. The results of whole-sediment toxicity tests showed a strong correlation between toxicity test results and pollutant concentrations. Selected cytosolic enzyme activities in digestive glands differed significantly depending on localities. These differences in enzyme activities were mainly related to the different pollutant levels of the sampling sites. The micro-organic contaminant profile patterns, toxicity tests and biomarker studies showed that shipyards and shipbreaking yards are the major potential sources of organic pollution in coastal areas.

Distribution of organochlorine pesticides in sediments and mussels from the Istanbul Strait

This study was conducted to determine the status and trends of organochlorine pesticide (OCP) compounds in the sediment and mussel samples collected along the Istanbul Strait and from the coasts of an island in the Marmara Sea. The total concentrations of OCPs were found in the range of 40-13,852 pg g(-1) dry weight for sediments and 5,195-12,322 pg g(-1) wet weight for mussels. The levels of OCPs in both sediments and mussels were dominated by DDTs and HCHs; β-HCH, 4,4(')-DDD and 4,4(')-DDE were the major pollutants. The degree of sediment pesticide contamination was more severe in the inner part of the strait. OCP concentrations in sediments and mussels were compared with the sediment guideline values and legal limits for human health, respectively. The results showed that OC pesticide contamination in the strait might not pose a serious threat to the health of the marine inhabitants at most of the stations.

Organochlorine pesticide residues in sediments from coastal environment of Cantabria (northern Spain) and evaluation of the Atlantic Ocean

This paper documents levels of organochlorine pesticides (OCs) in coastal surface sediments from selected reference sites on the northern Atlantic Spanish coast. One hundred eight samples covering three estuaries in the Cantabrian Coast were sampled in 2006 and analyzed in the finer fraction (<63 μm) for 19 OCs by gas chromatography with electron capture detector after confirmation by mass spectrometry. Detected organochlorine pesticides were endosulfan α, endosulfan β, endosulfan sulfate, hexachlorobenzene (HCB), aldrin, dieldrin, methoxychlor, 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4'-DDE) and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (4,4'-DDD). Total OCs concentrations ranged from 1.8 ng g(-1) dry weight (dw) to 3.9 ng g(-1) dw, showing a uniform distribution along the studied area, and being consistent with recorded levels in the literature for coastal sediments in other reference sites with low levels of pollution by OCs along the Atlantic Ocean. Endosulfan, 4,4'-DDD, HCB, aldrin, and dieldrin seemed to be ubiquitous as the legacy of past uses and deposition. OCs concentrations were significantly correlated to organic matter content and particle size distribution. No adverse biological effects derived from these pollutants are expected to take place as it can be concluded from the comparison with the existent marine sediment quality guidelines.

Distribution of petroleum hydrocarbons and organochlorinated contaminants in marine biota and coastal sediments from the ROPME Sea Area during 2005

The composition and spatial distribution of various petroleum hydrocarbons (PHs), comprising both aliphatic and polycyclic aromatic hydrocarbons (PAHs), and selected chlorinated pesticides and PCBs were measured in biota and coastal sediments from seven countries in the Persian Gulf and the Gulf of Oman (Bahrain, Iran, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Evidence of extensive marine contamination with respect to organochlorinated compounds and PHs was not observed. Only one site, namely the BAPCO oil refinery in Bahrain, was considered to be chronically contaminated. Comparison of the results from this survey for Σ DDTs and Σ PCBs in rock oysters from the Gulf of Oman with similar measurements made at the same locations over the past two decades indicates a temporal trend of overall decreasing Σ PCB concentrations in oysters, whereas Σ DDTs levels have little changed during that period.

Atlantic bluefin tuna (Thunnus thynnus) population dynamics delineated by organochlorine tracers

Atlantic bluefin tuna (ABFT) are highly valued and heavily exploited, and critical uncertainties regarding their population structure hinder effective management. Evidence supports the existence of two breeding populations of ABFT; a western population in the Gulf of Mexico and an eastern population in the Mediterranean Sea; both of which migrate and mix in the North Atlantic. Conventional tagging studies suggest low rates of trans-Atlantic migrations; however, electronic tagging and stable isotopes in otoliths indicate stock mixing up to 57% between management zones delineated by 45 degrees W longitude. Here we show that organochlorine pesticides and polychlorinated biphenyls (PCBs) can be used as tracers of bluefin tuna foraging grounds in the North Atlantic and confirm that stock mixing of juvenile tuna within the U.S. Mid Atlantic Bight is indeed high (33-83% eastern origin), and is likely spatially and temporally variable. We further demonstrate that >10% of the Mediterranean population is migratory, that young bluefin tuna migrate from the Mediterranean to western Atlantic foraging grounds as early as age 1, and then return to the Mediterranean Sea as young as age 5, presumably to breed. The tracer method described here provides a novel means for distinguishing bluefin tuna populations and ontogenetic shifts in migration in the North Atlantic.

Chlorinated hydrocarbons in marine biota and coastal sediments from the Gulf and Gulf of Oman

The spatial distribution of various organochlorinated compounds was investigated in the Gulf and Gulf of Oman based on marine biota (fish and various bivalves) and coastal sediment collected in Bahrain, Oman, Qatar and the United Arab Emirates (UAE) during 2000-2001. Several potential organic contaminants from agricultural (e.g., DDT and its breakdown products, lindane, endrin, dieldrin, endosulfan) and industrial (PCBs) sources were measured. Sediment burdens for all compounds, even for an apparent hot spot near a refinery in Bahrain, were amongst the lowest reported for surface sediments from other seas. Concentrations of DDTs were low in the muscle and liver of all fish (orange spotted grouper and the spangled emperor) analysed. Similarly, the levels of chlorinated hydrocarbons were low in the various bivalve species, notably rock oysters and pearl oysters. These results contribute to the sparse regional database for organochlorinated compounds in the marine environment. Moreover, they can be used as the most recent end point for elucidating temporal trends. Whereas the levels, albeit relatively low, SigmaDDTs in the rock oysters from the Gulf of Oman have remained uniform, there has been an irregular but generally decreasing trend in concentrations of summation SigmaPCBs during the last two decades.

Organochlorinated compounds in Caspian Sea sediments

Several organochlorinated contaminants, including numerous pesticides, were determined in coastal sediments from the Caspian Sea. The most important contaminants were p,p'-DDT (up to 7400 pg g(-1)) and its breakdown products, p,p'-DDD (up to 3400 pg g(-1)) and p,p'-DDE (up to 1300 pg g(-1)). Although the contamination was most severe in Azerbaijan, the sediment concentrations and percentage distribution of the three DDT-related compounds indicated that such contamination constitutes a contemporary and ubiquitous problem in the Caspian Sea. Lindane represented the second most significant contaminant, particularly in the Russian Federation, with concentrations up to 609 pg g(-1). The concentrations of HCB and other chlorinated pesticides (cis- and trans-chlordane, methoxychlor, heptachlor, heptachlor epoxide, aldrin, endrin, and endosulfans) were lower and not generally of concern, but the pesticides did demonstrate markedly different distributions reflecting differing agricultural usage in the region. The concentrations of Sigma PCBs were also quite low and ranged from 0.03 to 6.4 ng g(-1), with the highest amounts in the Russian Federation and Azerbaijan.