Environmental Contaminants levels in Traditional Fish Species and Harvesting Areas

The First Nation communities of Cape Breton have a longstanding relationship with the Bras d’Or Lakes, which have provided food and transportation for their people for centuries. In recent years, concerns have been raised regarding the possible contamination of traditional food fish by heavy metals and other chemicals resulting from the Sydney Tar Ponds, nearby industrial activities and other discharges.

Samples of various species of fish were collected and analysed for methylmercury, lead, arsenic, and cadmium. In addition, water and sediment samples were taken from the Bras d’Or Lakes as well as other costal areas in which Unama’ki First Nations typically fish. These water and sediment samples were analysed for methylmercury, DDT, lead, arsenic, and polycyclic aromatic hydrocarbons (PAHs). A human biomonitoring component was also included, in which hair samples were collected from participants in the study in order to test for levels of methylmercury.

The results of this study confirmed that the concentrations of contaminants in the samples were largely within acceptable limits, including those of methylmercury in the hair samples. However, the study authors recommended further analysis of fish using a larger sample size, given mercury’s subtle neurological effects in children. There was also some concern about mercury and cadmium levels in water and sediment samples. A final recommendation that came out of this study was that children and individuals who smoke should restrict the amount of oysters they eat per month due to the elevated lead and cadmium concentrations that were found in oyster samples.