A review of public health regulations on lead.

A review of public health regulations pertaining to lead exposure is the subject of this paper. Although lead had been used for centuries in the fabrication of a host of products, it was not until the mid-nineteenth century that the clinical pattern of lead poisoning was described in the medical literature. With this recognition gradually came government health regulations designed to limit human exposure to lead from occupational and environmental sources. The British, in particular, developed during the period 1890 to 1920 comprehensive rules and regulations pertaining to occupational lead exposures. The development and imposition of U.S. health regulations occurred later in the twentieth century; federal regulations not generally appearing until the 1970's. At present, several U.S. government agencies have promulgated regulations intended to prevent lead poisoning from paint; limit lead in ambient air, drinking water, workplace environments and consumer products; and reduce lead in fuels and fuel additives used in motor vehicles. These regulations are reviewed in terms of their extent of coverage. There is evidence, in some instances indirect in nature, that human exposure to lead in U.S. populations has been reduced, though comprehensive data are lacking. The Centers for Disease Control has reported that the mean blood lead level in the U.S. has decreased 36%, paralleling a reduction in the lead content of gasoline. For occupational lead exposure, comprehensive morbidity data do not exist, but an evaluation of NIOSH health hazard evaluations (HHE's) specific to lead show a gradual reduction since 1977 in the percentage of HHE's for which airborne lead exceeded 0.20 mg/m3, which at one time had been the federal standard for occupational lead exposure, prior to reduction of the U.S. standard to 0.05 mg/m3.