Borella P, Sturloni N, Rovesti S, Vivoli R, Bargellini A, Vivoli G
Dipartimento di Scienze Biomediche, Università degli Studi, Modena.
Ann Ist Super Sanita. 1998;34(1):97-104.
Potential neurotoxicity of lead in children has been explored in many recent epidemiological studies carried out all over the world. Within a multicentric European study, an investigation was carried out also in Italy on children living in an industrial area and characterised by a non steady-state exposure condition with higher exposure at the early stages of life. This peculiar feature allowed to observe interesting associations between neurobehavioural functions and the levels of Pb measured in teeth, but not in blood. Indeed, Pb in teeth was associated with the results of psychometric tests which evaluate the discriminant ability and the attention. Other associations, like those found between the intelligence quotient (IQ) scores and Pb in teeth disappeared after correction for the socioeconomical status of parents. In general, in children exposed to environmental Pb, more consistent associations were found with visual-motor integration and attention than with IQ measurements. In agreement with literature data from other countries, we suggest that the relevance of neurotoxic effects of Pb is limited, at least at the current exposure levels, but also that a threshold Pb level associated with no effect cannot be identified.
世界各地近期开展的许多流行病学研究都探讨了铅对儿童潜在的神经毒性。在一项多中心欧洲研究中,意大利也对居住在工业区的儿童进行了调查,这些儿童的特点是处于非稳态暴露状况,在生命早期阶段接触量较高。这一独特特征使得能够观察到神经行为功能与牙齿中而非血液中铅含量之间有趣的关联。事实上,牙齿中的铅与评估辨别能力和注意力的心理测试结果相关。其他关联,如智商(IQ)得分与牙齿中铅含量之间的关联,在对父母的社会经济地位进行校正后消失。总体而言,在接触环境铅的儿童中,与视觉运动整合和注意力的关联比与智商测量的关联更为一致。与其他国家的文献数据一致,我们认为,至少在当前暴露水平下,铅的神经毒性作用的相关性有限,而且也无法确定无效应的铅阈值水平。