MMWR Morb Mortal Wkly Rep. 1997 Feb 21;46(7):141-6.
Lead is an environmental toxicant that may deleteriously affect the nervous, hematopoietic, endocrine, renal, and reproductive systems. Lead exposure in young children is a particular hazard because children absorb lead more readily than do adults and because the developing nervous systems of children are more susceptible to the effects of lead. Blood lead levels (BLLs) at least as low as 10 micrograms/dL can adversely affect the behavior and development of children. CDC's National Health and Nutrition Examination surveys (NHANES), an ongoing series of national examinations of the health and nutritional status of the civilian noninstitutionalized population, have been the primary source for monitoring BLLs in the U.S. population. From NHANES II (conducted during 1976-1980) to Phase 1 of NHANES III (conducted during October 1988-September 1991), the geometric mean (GM) BLL for persons aged 1-74 years declined from 12.8 micrograms/dL, and the prevalence of elevated BLLs (BLLs > or = 10 micrograms/dL) decreased from 77.8% to 4.4%. This report updates national BLL estimated with data from Phase 2 of NHANES III (conducted during October 1991-September 1994), which indicate that BLLs in the U.S. population aged > or = 1 year continued to decrease and that BLLs among children aged 1-5 years were more likely to be elevated among those who were poor, non-Hispanic black, living in large metropolitan areas, or living in older housing.
铅是一种环境毒物，可能对神经、造血、内分泌、肾脏和生殖系统产生有害影响。幼儿接触铅是一种特别的危害，因为儿童比成人更容易吸收铅，而且儿童发育中的神经系统对铅的影响更敏感。血铅水平（BLLs）至少低至10微克/分升就可能对儿童的行为和发育产生不利影响。疾病控制与预防中心的国家健康和营养检查调查（NHANES）是对非机构化平民人口的健康和营养状况进行的一系列持续的全国性检查，一直是监测美国人群血铅水平的主要来源。从第二次国家健康和营养检查调查（1976 - 1980年进行）到第三次国家健康和营养检查调查的第一阶段（1988年10月 - 1991年9月进行），1 - 74岁人群的血铅几何平均值（GM）从12.8微克/分升下降，血铅水平升高（BLLs≥10微克/分升）的患病率从77.8%降至4.4%。本报告用第三次国家健康和营养检查调查第二阶段（1991年10月 - 1994年9月进行）的数据更新了全国血铅水平估计值，这些数据表明，美国1岁及以上人群的血铅水平继续下降，1 - 5岁儿童中，贫困、非西班牙裔黑人、居住在大城市地区或居住在老旧住房中的儿童血铅水平更有可能升高。
