Flame retardants organotin compounds and surfactants in opossum shrimps of the Scheldt estuary.
Context of the study
Flame retardants (like PBDEs) are used globally and are very persistent when they end up in the environment. Surfactants (like APE) have also been widely produced, and most of them end up in the aquatic environment. Together with organotin conpounts they are ofthen detected at high levels in estuarine waters world wide. All three groups might have long term effects on the endocrine system. Little is known however on how these compounds transfer to hyperbentic communities.Verslycke, T.; Vethaak, A.D.; Arijs, K.; Janssen, C.R. (2004). Flame retardants, surfactants and organotins in sediment and mysid shrimp of the Scheldt estuary (The Netherlands). Environ. Poll. 136(1): 19-31
Content of the study
In the Scheldt estuary (one of the most contaminated estuaries in Western Europe), organotin compounds, flame retardants and surfactants were measured in sediments and in opossum shrimp. Further it was examined whether the estuarine water, and sediments, showed estrogenic properties (and thus whether their are contaminants present which could act as estrogens).
Main results of the study
Concentrations of organotin compounds, APEs and PBDEs were high in opossum shrimp (1110 ng/g, 1119 ng/g and 2095 ng/g respectively) and lower in the sediments (219 ng/g, not detected and 272 ng/g). This result indicate that the Scheldt estuary is highly contaminated for organotin compounds (especially for TBT). This is due to shipping, since TBT is mostly used as a antifouling paints. TBT seams to accumulate in opossum shrimp at a much higher rate than in other species (perhaps due to lower TBT degradation), leading to higher concentrations in opossum shrimp than in fish. The PBDE concentrations are among the highest in Western Europe, and the values in opossum shrimp are extremely high. This is due to the high concentrations of PBDEs in the estuary (caused by industry in Antwerp, Terneuzen and other cities) and the fact that the opossum shrimp eat lots of suspended particulate matter. Since PBDEs are mostly adsorption|adsorbed to these particles the shrimp eat high amounts of PBDEs.The study also showed that the estuarine water, and sediments, contained a relative high concentration of substances which act as estrogens. It is suspected that this is due to the 3 groups of contaminants found.
This study concludes that the concern about potential effects of endocrine disrupting compounds on invertebrates in the Scheldt estuary are justified.
Verslycke, T.; Vethaak, A.D.; Arijs, K.; Janssen, C.R. (2004). Flame retardants, surfactants and organotins in sediment and mysid shrimp of the Scheldt estuary (The Netherlands). Environ. Poll. 136(1): 19-31
