For anyone wondering the relevance: Arsenic is released into the...

For anyone wondering the relevance:

Arsenic is released into the environment naturally through the weathering and erosion of sulphide minerals. [1] These sulphide minerals can form soils with very high concentrations of arsenic, and can dissolve in water. [1] An estimated 25% of arsenic emissions into the atmosphere come from natural sources, mostly volcanoes. [8] The majority of the arsenic released ends up in the soil and the ocean. [8]

Since valuable metals such as copper and gold can also be found in sulphide mineral deposits, mining exploration companies will often look for soil and water with a naturally high arsenic content as a means of locating an ore body. [9] It is therefore very important to establish baseline or existing arsenic concentrations in the surrounding environment in order to distinguish between human contamination and natural background levels. [10] The measurement of baseline concentrations is usually part of the environmental impact assessment processes practised in more than 100 countries. - See more at: http://www.miningfacts.org/Environm...-in-the-mining-industry/#sthash.jgZsdqAt.dpuf