Legacy Contaminants of Emerging Concern: Lead (Pb), Flint (MI), and Human Health

Abstract

As a heavy metal industrially mined for millenia, lead (Pb) is a legacy contaminant. It is also a contaminant of emerging concern because of its persistence, toxicity, and recent discovery of its resurgence in drinking water serving homes and schools, recently and most notoriously in Flint, Michigan. Concern about lead, however, has reemerged beyond Flint, exemplifying adoption of bad science policy despite availability of relevant good science. Much is known about lead toxicity, and profiled here. Whereas adults chronically exposed to lead may experience peripheral neuropathy, infants and children are more susceptible. They constitute sensitive subpopulations because their blood-brain barriers are immature, making them susceptible to central nervous system effects, most notably reduced IQ, when lead penetrates to developing brains. Failure to protect disadvantaged populations in Flint and beyond despite availability of proven science and inexpensive technology also exemplifies instances of environmental injustice. Emerging concern about lead thus illustrates failure of social as well as science policy. A critical lesson to be learned is that vigilance must be maintained, as knowledge about lead exposure and toxic effects provided by science does not automatically result in consistent and evenhanded legal and regulatory protection provided by government.

Keywords:

• lead
• Pb
• drinking water
• children’s health
• legacy contaminants
• contaminants of emerging concern
• human health risk assessment
• environmental justice
• science policy
• social policy

Notes

1 DDT: 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane,

PAHs: polycyclic aromatic hydrocarbons,

PCBs: polychlorinated biphenyls, and

PFCs: perfluoroalkyl compounds.

2 Apoptosis: “a type of cell death in which a series of molecular steps in a cell lead to its death. This is one method the body uses to get rid of unneeded or abnormal cells. The process of apoptosis may be blocked in cancer cells. Also called programmed cell death.” National Cancer Institute, NCI Dictionary of Cancer Terms, https://www.cancer.gov/publications/dictionaries/cancer-terms/def/apoptosis, access date 9 August 2019.

Additional information

Notes on contributors

Robert A. Michaels

Robert A. Michaels, PhD, CEP ([email protected]) is President of Schenectady-based RAM TRAC Corporation, and a toxicologist specializing in assessment and management of risks to public health potentially posed by environmental contaminants. He has served numerous corporate clients, the U.S. Congressional Office of Technology Assessment, and public interest organizations such as the Natural Resources Defense Council (NRDC). Dr. Michaels chaired the State of Maine Scientific Advisory Panel, and for 20 years chaired the Certification Review Board of the Academy of Board Certified Environmental Professionals (ABCEP). He has been Secretary of the NFPA Committee on Classification and Properties of Hazardous Chemicals, Board Member of the National Association of Environmental Professionals, and Member of the Editorial Advisory Boards of Springer-Verlag and Cambridge University Press science journals. He earned his doctorate at SUNY at Stony Brook in 1979, and in 2004 was awarded ABCEP’s Kramer Medal recognizing his professional contributions.