Health risk assessment of environmental selenium: Emerging evidence and challenges (Review).
New data have been accumulated in the scientific literature in recent years which allow a more adequate risk assessment of selenium with reference to human health. This new evidence comes from environmental studies, carried out in populations characterized by abnormally high or low selenium intakes, and from high-quality and large randomized controlled trials with selenium recently carried out in the US and in other countries. These trials have consistently shown no beneficial effect on cancer and cardiovascular risk, and have yielded indications of unexpected toxic effects of selenium exposure. Overall, these studies indicate that the minimal amount of environmental selenium which is source of risk to human health is much lower than anticipated on the basis of older studies, since toxic effects were shown at levels of intake as low as around 260 µg/day for organic selenium and around 16 µg/day for inorganic selenium. Conversely, populations with average selenium intake of less than 13-19 µg/day appear to be at risk of a severe cardiomyopathy, Keshan disease. Overall, there is the need to reconsider the selenium standards for dietary intake, drinking water, outdoor and indoor air levels, taking into account the recently discovered adverse health effects of low-dose selenium overexposure, and carefully assessing the significance of selenium-induced proteomic changes.
CREAGEN, Research Center of Environmental, Genetic and Nutritional Epidemiology, Section of Public Health, University of Modena and Reggio Emilia, Modena, Italy.
Marco
M
Vinceti
CREAGEN, Research Center of Environmental, Genetic and Nutritional Epidemiology, Section of Public Health, University of Modena and Reggio Emilia, Modena, Italy.
Tommaso
T
Filippini
CREAGEN, Research Center of Environmental, Genetic and Nutritional Epidemiology, Section of Public Health, University of Modena and Reggio Emilia, Modena, Italy.
Silvia
S
Cilloni
CREAGEN, Research Center of Environmental, Genetic and Nutritional Epidemiology, Section of Public Health, University of Modena and Reggio Emilia, Modena, Italy.
Annalisa
A
Bargellini
Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.
Anna Valeria
AV
Vergoni
Department of Forensic Sciences and Toxicology, University of Crete, Heraklion, Crete, Greece.
Aristides
A
Tsatsakis
Department of Medical, Surgical Sciences and Advanced Technologies 'G.F. Ingrassia', University of Catania, Catania, Italy.
Margherita
M
Ferrante
D009202:Cardiomyopathies / Q000209:etiology*; D002986:Clinical Trials as Topic; D019587:Dietary Supplements; D004769:Enterovirus Infections / Q000209:etiology*; D004785:Environmental Pollutants / Q000009:adverse effects*; D006801:Humans; D009369:Neoplasms / Q000517:prevention & control; D016566:Organoselenium Compounds / Q000008:administration & dosage / Q000009:adverse effects*; D018570:Risk Assessment; D012643:Selenium / Q000008:administration & dosage / Q000009:adverse effects*
D004785:Environmental Pollutants; D016566:Organoselenium Compounds; D012643:Selenium