Inorganic Arsenic Exposure Of The French General Population. Identification Of Toxicity Reference Values

Background and objectives. - The French national authority for health (Haute Autorite de sante [HAS]) and the French clinical toxicology society (Societe de toxicologie clinique [STC]) received a formal request from the French ministry for heath to elaborate recommendations for the screening of environmental overexposure to inorganic arsenic (iAs), for the medical management of overexposed patients and for the medical surveillance of exposed population. To allow these recommendations, characterizations of both the exposure of the French general population to iAs and its toxic effects, including the identification or the elaboration of toxicity reference values (TRY) for the protection of health. We report this preliminary evaluation.Methods. - Evaluations of inorganic arsenic toxicity conducted by national or international health agencies during the last 3 decades were all examined and analyzed. These evaluations were completed by literature retrieval through Medline and Scopus from January 2016 to December 2019.Results. - Repeated exposure to inorganic arsenic compounds can be responsible of various health effects. Because dose response relationship is well characterized for these effects and because they appear after the lowest cumulative exposures, non-carcinogenic skin effects of inorganic arsenic (hyperpigmentation and keratosis) should be considered as its critical non carcinogenic effects, and an oral TRV of 0.3 mu g/kg bw/d can be identified. Carcinogenic critical effects for the oral route are basocellular and epidermoid skin cancers with a unit risk of 1.5 x 10(-3) per mu g/kg bw/d. For inhalation exposure, the critical effect is the lung cancer risk with a unit risk of 3.3 x 10(-3) per mu g/m(3).Discussion. - The main source of inorganic arsenic exposure for the general population is food consumption (mainly water and cereals, especially rice). The last evaluations conducted in France indicate that the 95th percentile for alimentary exposure to inorganic arsenic was 0.46-0.51 mu g/kg bw/d in adults and 0.61-0.77 mu g/kg bw/d in 7-12 month children (part of the population with the highest exposure). These are higher levels than the recommended TRV for non-carcinogenic effects and correspond to a 6.9 x 10(-4)-1.2 x 10(-3) risk level for skin cancer. Because this background risk is high, other sources of environmental exposure to inorganic arsenic should be maintained as low as possible. (C) 2020 Societe Francaise de Toxicologie Analytique. Published by Elsevier Masson SAS. All rights reserved.