We are facing new challenges from an old adversary: children’s exposure to lead. First, in response to compelling evidence that blood lead levels (BLLs) once thought harmless have significant impact on children’s ability to learn, the Centers for Disease Control and Prevention (CDC) formally announced a reduction from the reference value (RV) of 5 µg/dL, established in 2012, to 3.5 µg/dL in October 2021.1 The RV is based on the 97.5% of the distribution of BLLs in US children as determined by the National Health and Nutrition Examination Survey. Second, blood lead testing for children has decreased both as a consequence of coronavirus disease precautions and the recall of the BLL point-of-care (POC) testing instrument.
Clinical Challenges
The challenges to pediatric health care providers (PHCPs) posed by these concurrent events are many. The revision of the RV has resulted in a doubling in the estimate of the number of children who require follow-up. This increased number will require additional time and effort investments by pediatric practices in connecting these children and their families to community services. At the same time, the rate of testing young children for lead exposure dramatically decreased early during the coronavirus disease crisis.2 In the first months of the pandemic in 2020, many office practices paused all well-child care. Families were in lockdown; many were afraid to risk exposure to the virus by taking children for a doctor’s appointment.3 More time spent at home, coupled with unsafe do-it-yourself home renovation projects, also increased the risk of lead exposure. Nationally, lead screening rates fell by an estimated 34% during the first 5 months of 2020.4 In 34 jurisdictions during January to May 2019, some 1 429 016 children were tested for lead and reported to the CDC compared with 948 844 during the same period in 2020.4 Thus, >480 000 children went untested between January and May 2020 versus the same period in 2019; an estimated 9600 children with elevated levels were missed because of the decline in testing.4 Although “catch-up” well-child care was reinstituted later in 2020 and has continued during 2021 and 2022, some states may not have seen a return to prepandemic rates of adherence with lead testing of eligible preschool children. Many children, now aged >3 years and missed during the pandemic, will never receive testing or remediation of lead hazards. Low-income, disadvantaged families, including those living in poorly maintained, older housing in disadvantaged “environmental justice” communities, who also face considerable barriers to accessing quality health care, will be disproportionately impacted by these circumstances.5,6 African-American children and immigrant and refugee children are more likely to have elevated BLLs, but because of disparities in access, may not have the necessary testing done.7
Against this backdrop, a major recall of the POC blood lead testing instrument, LeadCare II was announced.8 All testing with those devices was temporarily discontinued during the latter half of 2021; LeadCare II kit distribution has only resumed starting in February 2022. Because of the recall, office practices reverted to sending families to commercial or hospital-based laboratories for testing. Because families need to travel to the laboratory for testing and sometimes need to make a separate appointment for their child at the laboratory, parents may not follow through. The rate of adherence with lead testing is known to increase when POC testing is available.9 There are also concerns that some pediatric practices may not return to POC testing, even though the Food and Drug Administration has approved the resumption of LeadCare II kit production.
Opportunities
Renewed focus on children with BLLs greater than or equal to the RV provides an opportunity to promote dialogue about the importance of follow-up. PHCPs should:
Explore creative strategies, responsive to local conditions, to overcome barriers to BLL testing (eg, scheduling laboratory testing before an office visit, using e-systems to remind parents about needed tests, and/or using the electronic health record to identify missed screenings).
Counsel parents to get their homes inspected for lead hazards.
Ask about hobbies or occupations that may involve lead or imported goods, firearms rounds, jewelry, spices, ethnic remedies, or other contaminated products in the home.
Ask about the source of the family's drinking water.
Inquire about recent home renovation projects.
Offer nutritional guidance to maximize dietary source of iron, calcium, and other essential minerals and vitamins.
Review with parents the child’s developmental progress and refer families for assessment by local early intervention programs for children meeting age eligibility.
Inquire about behaviors that put children at risk including excessive oral exploratory habits and pica.
Offer simple measures to reduce the risk of further lead contamination, for example, removing shoes when entering the house; frequent dusting and damp mopping; cleaning up and covering chipping or peeling paint or plaster; opening older windows from the top; and frequent hand-washing.
Advocate for policies and statutes that control or eliminate sources of lead in the environment.
Public Health Challenges
The public health community is also facing challenges in its efforts to decrease children’s BLLs. A nearly 45-year trend of BLL decreases over time has stalled.10 The 97.5% BLL in children not declined in a decade.11 This leaves open the question of whether activities at the individual home level can be expected to reduce BLLs as low as 3.5 µg/dL. In most cases, no “smoking gun” for the lead exposure has been identified.12 The decrease in BLL testing also hampers state and local lead surveillance systems. Public health surveillance is critical for the identification and prevention of emerging/reemerging lead sources. The use of such local data to target populations and areas with disproportionate risk for lead exposure is foundational for population-based efforts to decrease exposure. In addition, jurisdictions’ ability to use surveillance data to compare progress within that jurisdiction over time has been hampered.
Opportunities
Widespread reduction in lead pollution has been the most effective strategy for reducing population BLLs. Public health agencies must integrate primary prevention strategies into their existing work. Efforts to reduce water lead levels by replacing lead pipes is expected to reduce average BLL.
Public health agencies should:
Ensure the entire lead pipe is replaced during system updates and maintenance.
Revise protocols and local ordinances to ensure that all units in multifamily housing are made lead-safe when a child with a BLL greater than or equal to their RV is identified in any unit.
Work with nonprofit and advocacy groups to advocate for increased resources for lead hazard abatement.
Work with refugee resettlement agencies to ensure that families are placed in lead-safe housing and children have BLL tests.
Work with local housing authorities to ensure that properties with rental subsidies comply with lead-safe regulations.
Work with local code enforcement and building departments to ensure that renovation of older homes is done safely.
Conclusion
No safe BLL threshold has been identified for children. Public health and clinical care providers need to implement and sustain open communication systems for exchanging information about cases, emerging sources, and areas with disparities in risk for BLLs greater than or equal to the RV. We urge parents, PHCPs, and the public health community to rise to these new challenges and continue to fight against childhood lead exposure by eliminating residential leaded paint and other environmental lead hazards. Together, we can work toward the overarching goal of bringing every newborn home to a lead-safe environment.
All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.
FUNDING: No external funding.
POTENTIAL CONFLICT OF INTEREST: Dr Woolf has no conflicts of interest to disclose. Dr Brown is a technical advisor for Magellan Scientific, manufacturer of the lead point-of-care testing instrument.
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