Ting David, Howd Robert A, Fan Anna M, Alexeeff George V
Pesticide and Environmental Toxicology Branch, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California 94612, USA.
Environ Health Perspect. 2006 Jun;114(6):881-6. doi: 10.1289/ehp.8684.
We evaluated animal and human toxicity data for perchlorate and identified reduction of thyroidal iodide uptake as the critical end point in the development of a health-protective drinking water level [also known as the public health goal (PHG)] for the chemical. This work was performed under the drinking water program of the Office of Environmental Health Hazard Assessment of the California Environmental Protection Agency. For dose-response characterization, we applied benchmark-dose modeling to human data and determined a point of departure (the 95% lower confidence limit for 5% inhibition of iodide uptake) of 0.0037 mg/kg/day. A PHG of 6 ppb was calculated by using an uncertainty factor of 10, a relative source contribution of 60%, and exposure assumptions specific to pregnant women. The California Department of Health Services will use the PHG, together with other considerations such as economic impact and engineering feasibility, to develop a California maximum contaminant level for perchlorate. We consider the PHG to be adequately protective of sensitive subpopulations, including pregnant women, their fetuses, infants, and people with hypothyroidism.
我们评估了高氯酸盐的动物和人体毒性数据，并确定甲状腺碘摄取减少是制定该化学品健康保护饮用水水平[也称为公共卫生目标（PHG）]过程中的关键终点。这项工作是在加利福尼亚州环境保护局环境健康危害评估办公室的饮用水项目下开展的。为了进行剂量反应特征描述，我们对人体数据应用了基准剂量模型，并确定了一个起始点（碘摄取抑制5%时的95%下限置信限）为0.0037毫克/千克/天。通过使用10的不确定性系数、60%的相对源贡献以及针对孕妇的暴露假设，计算出的PHG为6 ppb。加利福尼亚州卫生服务部将把PHG与其他因素（如经济影响和工程可行性）结合起来，制定加利福尼亚州高氯酸盐的最大污染物水平。我们认为PHG足以保护包括孕妇、其胎儿、婴儿以及甲状腺功能减退患者在内的敏感亚人群。
