| Author/Editor | | Alexander, Jan; Benford, Diane J; Boobis, Alan; Ceccatelli, Sandra; Cravedi, Jean-Pierre; Di Domenico, Alessandro; Doerge, Daniel; Dogliotti, Eugenia; Edler, Lutz; Filipič, Metka |
| Abstract | | Lead occurs primarily in the inorganic form in the environment. Human exposureis mainly via food and water, with some via air, dust and soil. In average adult consumers, lead dietary exposure ranges from 0.36 to 1.24, up to 2.43 micro g/kg body weight (b.w.) per day in high consumers in Europe. Exposure of infants ranges from 0.21 to 0.94 micro g/kg b.w. per day and in children from 0.80 to 3.10 (average consumers), up to 5.51 (high consumers) micro g/kg b.w. per day. Cereal products contribute most to dietary lead exposure, while dust and soil can be important non-dietary sources in children. Lead is absorbed more in children than in adults and accumulates in soft tissues and, over time, in bones. Half-lives of lead in blood and bone are approximately 30 days and 10-30 years, respectively, and excretion is primarily in urine and faeces. The Panel on Contaminants in the Food Chain (CONTAM Panel) identified developmental neurotoxicity in young children and cardiovascular effects and nephrotoxicity in adults as the critical effects for the risk assessment. The respective BMDLs derived from blood lead levels in micro g/L (corresponding dietary intake values in micro g/kg b.w. per day) were: developmental neurotoxicity BMDL01, 12 (0.50); effects on systolic bloodpressure BMDL01, 36 (1.50); effects on prevalence of chronic kidney disease BMDL10, 15 (0.63). The CONTAM Panel concluded that the current PTWI of 25 micro g/kg b.w. is no longer appropriate as there is no evidence for a threshold for critical lead-induced effects. In adults, children and infants the margins of exposures were such that the possibility of an effect from leadin some consumers, particularly in children from 1-7 years of age, cannot be excluded. Protection of children against the potential risk of neurodevelopmental effects would be protective for all other adverse effects of lead, in all populations.
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