People exposed to metals as hunting lodges replace mines.

Reglero, MM, MA Taggart, L Monsalve-Gonzalez and R Mateo. Heavy metal exposure in large game from a lead mining area: Effects on oxidative stress and fatty acid composition in liver. Environment Pollution doi:10.1016/j.envpol.2008.11.036.

None of the measured metals were at toxic levels, but the deer from the mining area had subtle changes in tissue biochemistry when compared to their neighbors from a non-mining area. The "observed biochemical changes in deer highlight the importance of the study of other sublethal effects to assess the impact of pollution on wildlife," say the authors.

Hunting lodges and hunters have now replaced the mines and miners. So, there may also be concern over human health. People who eat the region's contaminated animals are likely exposed to higher levels of metals than they normally would be. The metal mix may have adverse health effects, although more research is needed to make this connection in humans.

The study area in the southern Spanish province of Ciudad Real was mined for more than 2,100 years. Though mining stopped in 1990, more than 500 abandoned mines pepper the region. Miners extracted a range of metals; mainly lead and zinc, but also silver, copper, tin, antimony, tungsten, bismuth and arsenic.

The red deer and wild boar acted as animal sentinels in this study. The mammals -- which directly contact the local air, soil and water -- were compared to animals from a nearby, non-mined region.

Those living in the mining area had higher levels of lead, cadmium, copper and selenium in their liver and bones, the researchers reported. Glutathione (a protein that helps detoxify metals) and docosahexaenoic acid (a fat that helps proper brain development) were both reduced in animals from the mining region. The changes indicate very early damage that could lead to health problems.

Elevated metal exposures and the subtle physiology changes in wildlife raise concern about human exposures. Residents are exposed to the same water, air, and soils as the animals and could also pick up the metals. Hunters could be exposed by eating the meat.