Organochlorine pesticides and heavy metals in green mussel, Perna viridis in Singapore

The green mussel, Perna viridis, was used to measure bioaccumulated levels of organochlorine pesticides (OCPs), together with various heavy metals, in the marine environment of Singapore. Samples were collected from eight different locations in the coastal waters of Singapore between April and May 2002. OCPs (i.e. DDT, Chlordane, Mirex, hexachlorobenzene (HCB), pentachloronitrobenzene (PCNB) and Heptachlor) were quantified by gas chromatography-mass spectrometry. Heavy metals (i.e. As, Cd, Cr, Cu, Ni, Pb and Zn) were quantified by induced coupled plasma spectrometry. The concentration ranged from 2.6 to 54 ng g(-1) dw for DDTs (i.e. sum of p,p'-DDT, p,p'-DDD, o, p'-DDE and p, p'-DDE), 3.1 to 15 ng g(-1) dw for Chlordanes (i.e. sum of alpha- and gamma-chlordane) and 0.26 to 1.5 ng g(-1) dw for Mirex. These levels can be considered low when compared to reported values from similar studies conducted elsewhere in the world. Other pesticides were not detected. All heavy metals analysed were detected in all P. viridis samples, but only Cu, Pb, Zn and As were close to existing safety standards. Samples taken from locations adjacent to the main shipyards on the coastline and busy shipping lanes demonstrated peak levels of heavy metals and pesticides in the mussel tissues.