In order to assess the contamination of edible marine organisms in Quanzhou and Xinghua Bays,Fujian Province,China,concentrations of organochlorine pesticides(hexachlorocyclohexane isomers or HCHs and dichlorodiphenyltrichloroethane isomers/derivatives or DDTs) and heavy metals(Cu,Pb,Zn,As,Cr,Cd,Ni and Hg) in 13 species collected from different sites in the bays were analyzed by GC-ECD and ICP-MS.The concentration of the sum of DDTs exceeded that the sum of HCHs in the samples.Most of the organisms showed higher levels of DDTs than the first level criterion(10 ng/g) for marine biological quality in China(GB 18421-2001) but conformed to the first level criterion(20 ng/g) for HCHs.The estimated mean daily uptake of pesticides was below the level for minimal risk to the consumers.The levels of Cd,As and Pb in most organisms from both bays were markedly elevated and above the recommended legal limits for human consumption.Our results showed the need for routine monitoring of marine species contamination to ensure public and environmental health.
Mangala YatawaraOdhiambo Joshua OwagoJulia E Burnet
Soil samples collected from several sites along an altitudinal transect on the eastern slope of the Tibetan Plateau were analyzed for hexachlorobenzenes(HCHs) and dichlorodiphenyltrichloroethanes(DDTs).The results showed that HCHs and DDTs were found in the soil samples from the remote high altitude areas away from source regions,which confirmed the long-range atmospheric transport phenomenon of these organochlorine pesticides(OCPs) insecticides.The OCP concentrations in the soils had a significant negative correlation with altitude;they showed a trend to increase with decreasing altitude,but the increase was not continuous,being interrupted at some moderate-altitude sites on the transect.The distances from the source region,landforms,soil properties,and physical-chemical properties of OCPs were more important than total organic carbon content to the distribution of OCPs in soils disturbed by human activities.An analysis of the compositions of HCH isomers and DDTs revealed predominantly low ratios of α-HCH to γ-HCH,ranging from 0.06 to 4.79,which suggested current lindane inputs.On the other hand,low p,p-DDT/p,p-DDE and o,p-DDT/p,p-DDT ratios were observed,indicating mainly aged historical DDT residues in the study area.
XING Xin-LiQI Shi-HuaZHANG YuanYANG DanJ. O. ODHIAMBO
The concentrations of organochlorine pesticides (OCPs) in sediments from Xinghua (兴化) Bay,Fujian (福建) Province,China,were determined. The OCP concentrations ranged from 2.48 to 313.88 ng/g,with a more serious contamination in the upper sediment. But the OCP concentration in the upper layer was less than that in the lower sediment at the exit of the bay due to the influence of the Coriolis force. At the joint of the internal and external bays,OCPs accumulated abundantly because of freshwater and seawater mingling. The isomer percentage combined with isomer ratios indicated that DDTs (dichlorodiphengltrichloroethanes) were mainly derived from long-term weather soils,while lin-dane was introduced recently to the bay. The rivers flowing into the bay contributed more to DDT and HCH (hexachlorocyclohexane) contamination,especially at low tide. Compared with the corresponding quality guidelines from Ingersoll,the sediments from Xinghua Bay were likely to pose biological im-pairment and should be taken into account.
