The mistake could be made that the ingestion of seafood, for example, would contribute to health risks more than by drinking water. That assumption is false because even though the food contains a great deal of arsenic, it is of a low toxicity due to the fact that it is organic arsenic. On the other hand, groundwater contains inorganic arsenic. Inorganic arsenic has a much higher toxicity level than inorganic arsenic. This toxic arsenic found in groundwater may be of a lower level than organic arsenic found in the seafood, but it is imperatively more harmful.
Inorganic arsenic finds it way into the water supply in a variety of ways.
Erosion, dissolution of minerals and ores industrial effluents and by atmospheric deposition. 2 Different geographical areas of the United States have varying levels of arsenic as shown by the USGS representation in Figure 1. As shown in the above representation, the western states contain significantly higher levels of arsenic in drinking water than the rest of the country. Well, that question remains open for debate. 7 Various studies have shown the long term effects of arsenic exposure in varying amounts from different regions of the earth.