Arsenic can be found in both organic and inorganic forms and is not necessarily found in the environment unless it has been mobilized, which requires specific physical and chemical conditions. These physical and chemical conditions may occur naturally or be produced by various human activities.
Organic arsenic compounds, which are formed when arsenic combines with carbon, are less harmful to health and are rapidly eliminated by the body. Examples where organic arsenic is found include fish and shellfish.
Inorganic arsenic, formed when arsenic combines with elements such as oxygen, chlorine and sulfur, can be acutely toxic, particularly when it can be dissolved in water. Inorganic arsenic is present in more than 200 types of minerals and is most common in arsenopyrite, an iron arsenic sulfide. It can be found in soil, sediment and groundwater.
In the case of Paracatu, arsenic is part of the natural composition of minerals found in the soils, sediments and mineralogy of the rocks that contain minerals such as arsenopyrite found in the geological formation of Morro do Ouro, where Kinross operates. There are thirty-seven chemical elements found in Morro do Ouro, including arsenic that when combined, form various minerals, such as quartz, arsenopyrite and sericite.
The results of extensive scientific research involving years of data sampling by leading arsenic experts and diagnostic specialists in Brazil and abroad have found environmental exposure to arsenic in Paracatu to be low, with no evidence of adverse health effects related to arsenic. Kinross’ mining activities are considered to be a very minor contributor to overall arsenic exposure.