Lead: Risk Assessment Guidance for Lead in Blood

Date: May 2015
Chemical: Lead
CAS number: 7439-92-1
Endpoint(s): Nervous System
Elevated Blood Lead: 5 μg/dL blood (5 micrograms per deciliter blood)
Source: MDH, based on Centers for Disease Control and Prevention guidance (see Testing for Lead Poisoning in Children)

Minnesota Statutes 144.9501-144.9512, the Minnesota Lead Poisoning Prevention Act, were enacted to reduce exposures leading to harmful blood lead levels in children and pregnant women. On April 16, 2014, the Commissioner of Health issued a finding that changed the definition of an elevated blood lead level under Minnesota Statute 144.9501 to a blood lead level of five micrograms of lead per deciliter of whole blood (see Lead Laws and Rules).

At this time there is no level in blood that is known to be without harm to young children and MDH has not determined a level of lead in blood that poses a negligible risk to health. There is no known beneficial purpose for lead in the body. MDH’s finding that five micrograms per deciliter of blood is elevated is a policy decision related to prevention rather than an assessment of risk.

Similarly, MDH has not determined a level of lead in water that poses a negligible risk to health. MDH will continue to evaluate health information as it becomes available for possible development of guidance.

MDH findings for lead are consistent with the Federal Safe Drinking Water Act drinking water standard for lead. When developing a drinking water standard, the Safe Drinking Water Act requires the United States Environmental Protection Agency (US EPA) to first establish a Maximum Contaminant Level Goal (MCLG), which is the maximum level a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons is expected to occur, and which allows an adequate margin of safety. The MCLG for lead is zero. US EPA has set this level based on the best available science which shows there is no safe level of exposure to lead.

There are many environmental exposures to lead. Water is only one part of overall human exposure and there are also regulatory standards for building materials and soil.

More information

• Guidance values for water and air 
  Health Risk Assessment Unit
• Regulatory levels for public water supplies 
  Drinking Water Protection
• Health effects of lead and MDH Lead Prevention Program 
  Environmental Impacts Analysis Unit