Exposure to mercury: developing states facing increasing health, environmental risks: UNEP report

Communities in developing countries are facing increasing health and environmental risks linked to exposure to mercury, according to new studies by the United Nations Environment Programme (UNEP). The UNEP report, 'Global Mercury Assessment 2013', assesses for the first time at a global level releases of mercury into rivers and lakes.
It observed in the report that much human exposure to mercury is through the consumption of contaminated fish, making aquatic environments the critical link to human health. "Parts of Africa, Asia and South America could see increasing emissions of mercury into the environment, mainly due to the use of the toxic element in small-scale gold mining, and through the burning of coal for electricity generation," it added.
According to the report, emissions of the toxic metal from artisanal gold mining have doubled since 2005, in part due to new and better information, but also due to rising gold prices that are expected to lead to further increases. Also, due to rapid industrialisation, Asia is the largest regional emitter of mercury, and accounts for just under half of all global releases. In the past 100 years, man-made emissions have caused the amount of mercury in the top 100 meters of the world's oceans to double. Concentrations in deeper waters have increased by up to 25 percent.
The study, which provides a comprehensive breakdown of mercury emissions by region and economic sector, also highlights significant releases into the environment linked to contaminated sites and deforestation. It says an estimated 260 tonnes of mercury (previously held in soils) are being released into rivers and lakes. "Mercury released from industry and other man-made sources can circulate in the environment for up to centuries at a time. This means that it is likely to be several years or decades before reductions in mercury emissions have a demonstrable effect on mercury levels in nature and the food chain.