Changes

:Despite its notoriety as a deadly poison, arsenic is an essential trace element for some animals, and maybe even for humans, although the necessary intake may be as low as 0.01 mg/day.<ref>[http://www.lenntech.com/periodic/elements/as.htm#Health%20effects%20of%20arsenic#ixzz1NrfnT6IU Arsenic (As) - Chemical properties, Health and Environmental effects]</ref>

:Despite its notoriety as a deadly poison, arsenic is an essential trace element for some animals, and maybe even for humans, although the necessary intake may be as low as 0.01 mg/day.<ref>[http://www.lenntech.com/periodic/elements/as.htm#Health%20effects%20of%20arsenic#ixzz1NrfnT6IU Arsenic (As) - Chemical properties, Health and Environmental effects]</ref>

:Desirable arsenic concentrations in the body seem to be reasonable. This consideration results in the conclusion that arsenic could play an essential role in human health. Thus, reference arsenic concentrations in different human tissues and body fluids should be established in order to recognize not only arsenic intoxication, but also arsenic deficiency.<ref>[http://www.ncbi.nlm.nih.gov/pubmed/7682827 Essential trace elements in humans. Serum arsenic concentrations in hemodialysis patients in comparison to healthy controls] - Biol Trace Elem Res. 1993 Apr;37(1):27-38.</ref>

:Desirable arsenic concentrations in the body seem to be reasonable. This consideration results in the conclusion that arsenic could play an essential role in human health. Thus, reference arsenic concentrations in different human tissues and body fluids should be established in order to recognize not only arsenic intoxication, but also arsenic deficiency.<ref>[https://www.ncbi.nlm.nih.gov/pubmed/7682827 Essential trace elements in humans. Serum arsenic concentrations in hemodialysis patients in comparison to healthy controls] - Biol Trace Elem Res. 1993 Apr;37(1):27-38.</ref>

==External links==

==External links==