Body burden of metals and persistent organic pollutants among Inuit in the Canadian Arctic.

Inuit living in the Arctic are exposed to elevated levels of environmental contaminants primarily due to long-range atmospheric transport. Blood sampling and contaminant biomonitoring was conducted as part of the International Polar Year Inuit Health Survey in 2007-2008. The body burden of metals (e.g. Cd, Pb) and persistent organic pollutants (e.g. PCBs, DDT & DDE, toxaphene, chlordane, PBDEs) were measured for Inuit participants (n=2172) from 36 communities in Nunavut, Nunatsiavut, and the Inuvialuit Settlement Region, in Canada. The geometric mean of blood concentrations for Cd, Pb, PCBs, DDE & DDT, toxaphene, and chlordane were higher than those in the Canadian general population. A total of 9% of study participants exceeded the intervention guideline of 100µgL(-1) for Pb, 11% of participants exceeded the trigger guideline of 5µgL(-1) for Cd, and 1% exceeded the intervention guideline of 100µgL(-1) for PCBs. Also, 3% of women of child-bearing age exceeded blood Pb of 100µgL(-1) while 28% of women of child-bearing age exceeded 5µgL(-1) of PCBs. This work showed that most Inuit Health Survey participants were below blood contaminant guidelines set by Health Canada but that metal and POP body burdens commonly exceed exposures observed in the general population of Canada.

Corporate crime: why we cannot trust industry-derived safety studies.

The control of pesticides, as of all synthetic chemicals, in most industrialized countries relies heavily or even entirely on safety data supplied by the manufacturers. Such a regulatory system can only be effective if the companies conducting and reporting the studies honestly disclose any adverse findings. The record shows, however, that all too often company executives and their scientists knowingly suppress or manipulate information that could affect the licensing and sale of their products. A case in point is the gross manipulation of health and related data on the pesticides heptachlor and chlordane by the U.S. chemical company, Velsicol.

Persistence of residues in water and sediment of a fresh-water lake after surface application of technical chlordane.

A fresh-water lake, free from detectable pesticide residues before this study, was treated with a commercial formulation of technical chlordane. Water and sediment samples were analysed for chlordane residues 7, 24, 52, 279. and 421 days after treatment. Residues moved rapidly from the water to the lake bottom, supporting earlier results of a laboratory study with other organochlorines. In water, alpha- and gamma-chlordane concentrations remained proportional to total chlordane concentrations, as determined by total-peak area measurements of gas-liquid chromatogrammes. But in bottom sediments, alpha- and gamma-chlordane were more persistent than other constituents of technical chlordane, supporting recent evidence that quantification of technical chlordane residues on the basis of gamma-chlordane quantification only (or that of alpha- and gamma-chlordane only), can lead to incorrect results and that this method, although simple and fast, should no longer be recommended.