锰(Mn)的暴露与神经行为效应有关。对于焊接中是否经常发生的暴露存在分歧,铁合金,和其他工业过程产生神经学上显著的神经行为变化,代表帕金森病。对锰的人类流行病学文献中的方法学问题进行了综述:(1)专注于特发性帕金森病的研究,而不考虑锰。帕金森综合征;(2)具有健康工人效应偏倚的研究;(3)具有有问题的统计模型的研究;(4)源自诉讼案例系列的研究。通过适当的研究设计和暴露评估进行的调查显示,一致的神经行为效应以及可归因于的亚临床和临床体征和障碍症状。28项研究表明锰与神经行为效应之间存在暴露-反应关系,包括11个连续曝光指标和6个三个或四个对比曝光水平。持续低浓度暴露于锰的影响与早期锰中毒的表现一致,即,与帕金森主义一致。这是令人信服的证据,表明Mn是一种神经毒性化学物质,并且有充分的证据表明,Mn暴露于远低于当前美国标准5.0mg/m(3)的Mn会导致损害。
Exposure to manganese (Mn) is associated with neurobehavioral effects. There is disagreement on whether commonly occurring exposures in welding, ferroalloy, and other industrial processes produce neurologically significant neurobehavioral changes representing parkinsonism. A
review of methodological issues in the human epidemiological literature on Mn identified: (1) studies focused on idiopathic Parkinson disease without considering manganism, a parkinsonian syndrome; (2) studies with healthy worker effect bias; (3) studies with problematic statistical modeling; and (4) studies arising from case series derived from litigation. Investigations with adequate study design and exposure assessment revealed consistent neurobehavioral effects and attributable subclinical and clinical signs and symptoms of impairment. Twenty-eight studies show an exposure-response relationship between Mn and neurobehavioral effects, including 11 with continuous exposure metrics and six with three or four levels of contrasted exposure. The effects of sustained low-concentration exposures to Mn are consistent with the manifestations of early manganism, i.e., consistent with parkinsonism. This is compelling evidence that Mn is a neurotoxic chemical and there is good evidence that Mn exposures far below the current US standard of 5.0 mg/m(3) are causing impairment.