ИСТИНА

Arsenic contamination of groundwater due to natural processes (weathering of soil and bedrock) is a well-known problem in Asia. However, anthropogenic activities, such as mining, agriculture and other industries, may considerably increase arsenic inputs to aqueous systems. Arsenic contamination is further coupled to climate change, which may alter hydrological conditions and change the As transport pathways and As concentrations of aqueous systems. We study the impact of mining and hydroclimatic changes on arsenic contamination within the Lake Baikal Drainage basin. Results show that As concentrations, in both ground and surface waters, often exceed WHO permissible levels. Additionally, net increases in loads to riverine systems are seen as a result of mining activities. Considering also pressures related to projected hydroclimatic changes, these results call for continued monitoring and modelling of arsenic spreading to this unique ecosystem and freshwater resource.