Exposure of the Inuit population of Nunavik (Arctic Quebec) to lead and mercury

The authors conducted a survey during 1992 to evaluate blood levels of lead and mercury in Inuit adults of Nunavik (Arctic Quebec, Canada). Blood samples obtained from 492 participants (209 males and 283 females; mean age=35 yr) were analyzed for lead and total mercury; mean (geometric) concentrations were 0.42 mu mol/l (range=0.04-2.28 Nmol/l) and 79.6 nmol/l (range = 4-560 nmol/l), respectively. Concentrations of omega-3 fatty acid in plasma phospholipids-a biomarker of marine food consumption-were correlated with mercury (r=.56, p<.001) and, to a lesser extent, with blood lead levels (r=.31, p<.001). Analyses of variance further revealed that smoking, age, and consumption of waterfowl were associated with lead concentrations (r =.30, p<.001), whereas age and consumption of seal and beluga whale were related to total mercury levels (r(2) =.30, p<.001). A significant proportion of reproductive-age women had lead and mercury concentrations that exceeded those that have been reportedly associated with subtle neurodevelopmental deficits in other populations.