Trace metals in scalp hair of children and adults in three Alberta Indian villages.

This study examined trace metal levels in scalp hair taken from 122 children and 27 adult residents of three small northern Alberta (Canada) Indian villages, one of which is situated close to the world's first tar sands oil extraction plants. The three communities studied were: Fort McKay (the exposed village), Fort Chipewyan (also in the tar sands ecosystem but distant from the plants), and Garden River (not in the tar sands ecosystem). Inductively coupled argon plasma emission spectroscopy was used to determine hair sample metal content. Nineteen metals were included in data analysis. Children from Fort McKay had the highest average hair lead, cadmium and nickel levels. Chromium levels were approximately equal in hair from Fort McKay and Garden River children, and significantly elevated above levels found in the hair of Fort Chipewyan children. Children from Garden River showed highest hair levels of eight metals: vanadium, aluminum, iron, manganese, barium, zinc, magnesium and calcium. Fort Chipewyan children had the highest hair levels of copper, but the lowest levels of all other metals. Among adults, hair lead, nickel and cadmium levels were highest in Fort McKay residents, while phosphorous and vanadium were highest in hair from Garden River residents. Bioaccumulation of lead, cadmium, nickel and chromium in hair from Fort McKay residents may be related to exposure to extraction plant pollution. Plant stack emissions are known to contain appreciable amounts of lead, nickel and chromium. Spills into the Athabasca River, until recently the source of Fort McKay drinking water, have been reported from plant wastewater holding ponds, known to contain elevated levels of lead, nickel and cadmium. An increased number of significant metal-metal correlations in hair metal levels for Fort McKay children suggests a richer source of multiple metal exposure, relative to children in the other two communities.