Organochlorines and trace elements in upland game birds harvested in Canada

Abstract

American woodcock, common snipe, two species of ptarmigan (willow and rock), and three species of grouse (ruffed, spruce, and sharp-tailed) were collected from 21 locations between 1991 and 1994 as part of a nationwide survey of contaminants in game birds harvested in Canada. Breast muscle was analysed for organochlorines (chlorobenzenes, hexachlorocyclohexanes, chlordane-related compounds, DDT metabolites, mirex, dieldrin, and PCBs) and trace elements (Hg, Cd, Se, and As). The concentrations of organochlorine compounds measured in breast muscle of the birds in this survey were very low. Median concentrations for the organochlorines measured were less than 0.001 mg kg-1 in breast muscle of all ptarmigan and grouse species sampled. Only SigmaPCB, SigmaDDT and SigmaCHL were found above trace levels in breast muscle of all of the woodcock, and only SigmaPCB and SigmaDDT were found above trace levels in the snipe. Total Hg was detected only in the woodcock and the snipe whereas Se was above detection levels in all samples of all species except one sample pool of willow ptarmigan from Nunavut. Cadmium was detected in all species except for the spruce and sharp-tailed grouse with the highest overall concentrations found in the ptarmigan species. Arsenic was detected in all of the woodcock and snipe samples but was not found in any of the grouse samples. The highest Hg and As concentrations were both found in snipe sampled from southeastern New Brunswick. Concentrations of As, Hg and Se measured in breast muscle of the birds in this survey were below toxicological threshold levels found in the literature. Concentrations of Cd, however, were elevated in some birds, particularly in willow ptarmigan from the Yukon. Health Canada determined that the organochlorine and trace element levels found in samples of breast muscle of game birds analysed in this study did not pose a health hazard to human consumers and therefore these birds were safe to eat.