Crustaceans at 10,000 metre depths contain higher concentrations of chemicals than some animals in coastal waters
Research reported in this month’s NATURE shows that toxic chemicals, including anti-fouling compounds from ship hulls, are accumulating in marine creatures in Earth’s deepest oceanic trenches.
The research, conducted from the University of Aberdeen and presented at a conference inShanghai, details the first measurements of organic pollutants at 7,000 to 10,000 metre depths. Previous studies of pollutants in deep-sea organisms had only gone as far down as 2,000 metres.
Alan Jamieson and colleagues at Aberdeen tested for levels of organic chemicals in amphipods from the western Pacific Mariana Trench and the Kermadec Trench near New Zealand.
Amphipods from these areas contained polychlorinated biphenyls (PCBs) — which have been used to make plastics and as anti-fouling agents on ship hulls – and polybrominated diphenyl ethers (PBDEs), used as flame retardants.
Both PCBs and PBDEs are carbon-based compounds and are considered persistent organic pollutants (POPs) because they are hard to break down. Production of the carcinogenic PCBs has been banned in many countries since the late 1970s, but in other studies paint samples from ships as late as 1996 have revealed the presence of PCBs. PBDEs meanwhile are only now being phased out. Animal studies suggest that PBDEs disrupt hormone systems and interfere with neural development.
See the NATURE article here