Organoarsenical compounds: Occurrence, toxicology and biotransformation

Arsenic is a ubiquitous metalloid found in the environment. Its chronic exposure is of global health concern as it causes lung, skin and bladder cancers, as well as non-cancer illness such as skin lesions, and cardiovascular and neurological diseases. While the environmental occurrence, fate, and toxicity of inorganic As has been well documented, limited research is available on organic As compounds. Organic As compounds often result from As metabolism in marine organisms, but they also enter the biosphere through anthropogenic activities including feed additives for livestock. Here, the state of knowledge on organic As is reviewed, encompassing their occurrence, toxicology and biotransformation including biosynthesis, methylation, and degradation. Knowledge gaps and possible research directions are identified, including metabolic pathways of synthesis and degradation, the impacts of metabolic transformations on toxicity and development of new analytical methods.