Lead is a metal that has developmental neurotoxic properties for humans and is found naturally in the environment. The effects of lead poisoning—including death, cognitive and central nervous system impairment, and sterility—have been recognized for thousands of years. The industrial revolution increased usage of lead and the atmospheric spread of aerosolized lead particles significantly, contributing to increased blood lead levels among US children from 1900 to 1975. In response, exposure to specific sources were addressed with 1970s’ and 1980s’ federal policies to remove lead in paint and passenger car gasoline. As a result, childhood lead poisoning rates plunged during 1975 to 2000, from previously observed peaks, giving the impression that the problem was solved.
Since that time, increasing lead use in industries, infrastructure renewal projects exposing lead components, expansion of global trade, and, with it, uncertain sources of manufactured goods have all increased exposure potential. Legacy traces of lead are found in paint and pipes of homes built before 1978 and in aging community infrastructure, in soil contaminated by leaded gasoline, or around crumbling industrial sites. Lead can be inhaled in dust particles or in fumes from burning lead-painted wood. Imported cookware and food products, toys and toy jewelry, imported cosmetics, spices, and folk remedies may contain lead. Other routes of exposure include lead used in arts and crafts, take-home lead from occupations using lead products, and from firearms, ammunition, and fishing tackle. Such potential exposure routes continue to pose public health risks, as the Flint, Michigan, water crisis demonstrated in 2014, which reintroduced lead to public discourse. The proliferation of lead sources influenced researchers to continue building evidence on lead’s hazards.
Multiple scholars in the past 40 years chronicled the continuing threat that environmental lead poses to humankind, especially for children ages 0 to 5 years, and that there is no safe level of lead exposure. Scholars have produced a flow of published research confirming the harmful effects of lead at lower and lower exposure levels. The Centers for Disease Control and Prevention currently uses a blood lead reference value of 3.5 micrograms of lead per deciliter of blood. Children with blood lead levels at or above the reference value are among the top 2.5% of US children with the highest blood lead levels.
Images of populations affected by childhood lead poisoning are generally of disadvantaged inner-city minority children, chewing on paint chips peeling from the walls in dilapidated public housing, which gives the impression that lead poisoning risk is restricted to certain populations. To be sure, evidence clearly demonstrates that children living in poverty and minority children bear a disproportionate risk of exposure. However, given the almost ubiquitous nature of lead, wider swaths of children are potentially at risk.
The time for action is now. Lead poisoning prevention is complex and requires a recalibration of current public health approaches and perspectives. Lead poisoning prevention, as a model for the future of public health, forces us to boldly confront health equity issues such as safe housing, clean drinking water, safe schools and childcare facilities, environmental justice, community infrastructure repair, occupational risks, and so on. We must protect young children from exposure to lead to ensure that future leaders have the mental capacity to confront the challenges ahead. Thus, childhood lead exposure prevention should be a national priority.
[For additional reading, please see the Appendix, available as a supplement to the online version of this article at https://www.ajph.org.]
Tanya Telfair LeBlanc, PhD, MS
Erik Robert Svendsen, PhD
Paul Allwood, PhD
Guest Editors
Division of Environmental Health Science and Practice
National Center for Environmental Health
Centers for Disease Control and Prevention
6. Years Ago
Elevated Blood Lead Levels in Children Associated With the Flint Drinking Water Crisis
Through vigilant public health efforts, lead exposure has fallen dramatically over the past 30 years. With the increasing recognition that no identifiable BLL is safe and without deleterious and irreversible health outcomes, Healthy People 2020 identified the elimination of EBLLs and underlying disparities in lead exposure as a goal. Regrettably, our research reveals that the potentially increasing threat of lead in drinking water may dampen the significant strides in childhood lead-prevention efforts. As our aging water infrastructures continue to decay, and as communities across the nation struggle with finances and water supply sources, the situation in Flint, Michigan, may be a harbinger for future safe drinking-water challenges. Ironically, even when one is surrounded by the Great Lakes, safe drinking water is not a guarantee.
From AJPH, February 2016, p. 288
86. Years Ago
Lead Pipes as a Source of Lead in Drinking Water
The literature is quite replete with reports of lead poisoning, and not the least common source is water. In some instances the occurrence of lead poisoning from water has been so extensive as to be spoken of as an epidemic. . . . [T]he use of lead pipes in connecting the mains to the domestic pipelines is a usual practice. Furthermore we are aware of the fact that in some communities, many domestic service pipelines are of lead throughout. It seems entirely plausible that the sporadic cases of lead poisoning, and possible illnesses that are not diagnosed and recorded at all, may be due to a number of circumstances connected with lead service pipes.
From AJPH, August 1936, p. 778
Biography
Note. The findings and conclusions in this editorial are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention or the Agency for Toxic Substances and Disease Registry.