Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts 02115 , USA.
Environ Health Perspect. 2012 Apr;120(4):501-7. doi: 10.1289/ehp.1104170. Epub 2011 Dec 19.
The impact of environmental chemicals on children's neurodevelopment is sometimes dismissed as unimportant because the magnitude of the impairments are considered to be clinically insignificant. Such a judgment reflects a failure to distinguish between individual and population risk. The population impact of a risk factor depends on both its effect size and its distribution (or incidence/prevalence).
The objective was to develop a strategy for taking into account the distribution (or incidence/prevalence) of a risk factor, as well as its effect size, in order to estimate its population impact on neurodevelopment of children.
The total numbers of Full-Scale IQ points lost among U.S. children 0-5 years of age were estimated for chemicals (methylmercury, organophosphate pesticides, lead) and a variety of medical conditions and events (e.g., preterm birth, traumatic brain injury, brain tumors, congenital heart disease).
Although the data required for the analysis were available for only three environmental chemicals (methylmercury, organophosphate pesticides, lead), the results suggest that their contributions to neurodevelopmental morbidity are substantial, exceeding those of many nonchemical risk factors.
A method for comparing the relative contributions of different risk factors provides a rational basis for establishing priorities for reducing neurodevelopmental morbidity in children.
环境化学物质对儿童神经发育的影响有时被认为不重要，因为损害的程度被认为在临床上无足轻重。这种判断反映了未能区分个体风险和人群风险。风险因素对人群的影响取决于其效应大小和分布（或发病率/患病率）。
旨在制定一种策略，既要考虑风险因素的分布（或发病率/患病率），又要考虑其效应大小，以便估计其对儿童神经发育的人群影响。
估计了美国 0-5 岁儿童因化学物质（甲基汞、有机磷农药、铅）和各种医疗状况和事件（例如早产、脑外伤、脑肿瘤、先天性心脏病）而丧失的全量表智商点数。
尽管分析所需的数据仅可用于三种环境化学物质（甲基汞、有机磷农药、铅），但结果表明，它们对神经发育发病率的贡献很大，超过了许多非化学风险因素。
一种比较不同风险因素相对贡献的方法为确定减少儿童神经发育发病率的优先事项提供了合理的依据。
