Impact of Informal and Illegal Alluvial Artisanal and Small-Scale Gold Mining in the Madre de Dios River Basin, Peru: Total Mercury Levels in Human and Farmed Fish Populations

Abstract

Alluvial gold mining in the region of Madre de Dios, Peru has caused extensive environmental degradation, human health risks, and social unrest. Poor legislation and strong political pressure has prevented the regional government from regulating artisanal small-scale gold mining. In March of 2012, local police clashed with 15,000 mining federation protesters in the capital city of Puerto Maldonado (Gardner, 2012). Several smaller conflicts between military police and local populations have since ensued, yet little has been accomplished by the government in the way of legal reform. Meanwhile, artisanal small-scale gold mining in the region continues. Large tracts of lowland rainforest are transformed to desert (see figure 1), human populations are exposed to mercury health risks, and the ecosystem becomes increasingly impacted by the anthropogenic inputs of mercury into the environment. Samples of human hair showed that location was an important factor in predicted mercury levels. Samples of fish tissue from aquaculture ponds in Madre de Dios showed levels of mercury below the reference level at the halfway point in production. The conclusion supports the need for artisanal small-scale gold mining regulation. In addition, the author concludes that the underlying causes of continued unregulated alluvial mining in the area rests at least in part on the international community’s failure to enact and enforce appropriate international environmental policies.