ias continues to poison the drinking water of tens of millions of people around the world

iAs continues to poison the drinking water of tens of millions of people around the world

>63,000 wells over 10 yrsMax=800 ppb1436 wells contaminated above 10 ppbHundreds exceeded 50 ppb

More than 2.3 million people in North Carolina use water from private, unregulated wells

Sanders et al 2011

Data from 2009

Sanders et al 2011

Data from 2009

75,000 people

More than 2.3 million people in North Carolina use water from private, unregulated wells

>63,000 wells over 10 yrsMax=800 ppb1436 wells contaminated above 10 ppbHundreds exceeded 50 ppb

Cytochrome c oxidase• The enzyme cytochrome c

oxidase or Complex IV) is a large transmembrane protein complex found in bacteria and the mitochondrion.

• The complex contains two hemes a cytochrome a and cytochrome a3, and two copper centers, the CuA and CuB centers

1

2

3

Cd and Zn transporters

Methylmercury and methionine

Monovalent, divalent

elemental

inorganic

Inhibits ability to make hemoglobin

Cr(VI) is generally considered 1,000 times more toxic than Cr(III) [EPA 1998; ATSDR 2000; Dayan and Paine 2001].

• The toxicity of chromium compounds depends on the oxidation state of the metal.

• Occupational exposure to chromium(VI) compounds has been associated with increased incidence of lung cancer.

• Chromium(III) is an essential nutrient that can be toxic in large doses.