North Carolina

When CDC lowered the blood lead reference value (BLRV) for children from 5 µg/dL to 3.5 µg/dL in the fall of 2021, the North Carolina Childhood Lead Poisoning Prevention Program (NC CLPPP) needed to revise the blood lead testing and follow-up schedule used by clinicians for case management of children under the age of six years to align with CDC. Feedback from clinics indicated some had difficulty using the guidance revised in 2018, including misunderstandings about minimum time periods for performing a confirmatory diagnostic lead test. This often resulted in delays in performing these tests. Some clinics also misunderstood what actions were required after the diagnostic tests.

In 2014, NC CLPPP enlisted the help of the University of North Carolina Institute for the Environment (UNC IE) to successfully establish the NC Lead and Healthy Homes Outreach Task Force. Building on the network of public health professionals on the task force, NC CLPPP and UNC IE created the Ad Hoc Lead Surveillance Advisory Committee. The committee, consisting of 25 task force members representing 17 clinical and public health organizations, met in December 2021 and February 2022 to redesign the state blood lead testing and follow-up schedule.

During the first meeting, committee members discussed the impact of the lower BLRV on clinical and environmental follow-up recommendations. They also discussed improving other aspects of the revised testing and follow-up schedule. In the second meeting, the committee provided feedback for the final version of the follow-up schedule and suggested strategies for outreach to clinical and public health agencies. The new follow-up schedule advises that clinical follow-up should begin at 3.5 µg/dL to match the CDC BLRV.

On the advice of the committee, NC CLPPP used several outreach channels to announce the revised follow-up schedule on March 21, 2022. NC CLPPP and UNC IE electronically distributed the revised schedule to more than 600 public health and private medical professionals and published it on their websites. The NC CLPPP program manager also presented the new follow-up schedule at a meeting of the NC Pediatric Society.

Based on pre-pandemic blood lead data from 2019, the new BLRV and the revised follow-up schedule have the potential to provide up to 2,000 children and their families with important educational information about lead, including sources of exposure and prevention measures. This represents a four-fold increase from approximately 500 children and their families in 2019 who had blood lead levels of 5 µg/dL or higher that were eligible for these services. This effort also enhanced coordination and developed stronger relationships between NC CLPPP and other professional, local, and state organizations and agencies that focus on the health of children, women, and refugees.

In May 2016, a North Carolina Childhood Lead Poisoning Prevention Program (NC CLPPP) epidemiologist noted clusters of elevated blood lead levels (BLL) among 16 children documented as take-home lead exposures in North Carolina’s lead surveillance system. Local lead investigators visited the homes of the children with confirmed BLLs greater than 5 micrograms per deciliter (µg/dL). They found lead dust on household members’ work boots, laundry areas, car upholstery, and children’s car seats. NC CLPPP partnered with North Carolina’s Occupational and Environmental Epidemiology Branch (OEEB), which houses the Adult Blood Lead Surveillance (ABLES) program. Through this partnership, NC CLPPP determined that the children’s exposures were linked to employees of two workplaces: a lead oxide manufacturer with 26 current employees and a battery manufacturer with over 400 employees. As the employees resided in multiple counties, the investigation crossed many jurisdictional boundaries. Concurrently, the North Carolina Occupational Safety and Health (NC OSH) Compliance Branch was investigating a complaint about the lead oxide manufactuer.

In July 2016, the  NC CLPPP worked with the local county health department to offer seminars to employees of each company on how to protect their household and themselves from lead exposure. The NC CLPPP team notified local health directors in employees’ home counties, coordinated with the State Laboratory of Public Health to provide free blood lead level testing to employees’ household members at local health departments, and urged private practices to retest affected patients. Few household members came to the health department for blood lead testing; however, private practices responded by testing many of the children at their next visit. OEEB industrial hygienists conducted site visits at the facilities, suggested improvements in engineering controls, and reviewed company policies for potential interventions. Due to the consistently elevated BLLs among the lead oxide manufactoring workers, OEEB epidemiologists and an occupational health nurses interviewed employees about their work procedures and personal hygiene.

Major successes of this investigation include enhanced coordination and stronger relationships between the NC CLPPP, ABLES, and external agencies including NC OSH, NC Division of Waste Management, and the county health department where these workplaces are located — each of which are crucial for navigating restrictions of jurisdictional boundaries. A written workflow was developed for improved coordination of future cases. New fields were created in North Carolina’s lead surveillance system (NCLEAD) for capturing company name and occupational exposures to alert NCLEAD data personnel of potential occupational clusters. NC CLPPP drafted questions for ABLES case investigation interviews to assist in linkage of family members. NC CLPPP now also coordinates with ABLES to provide counseling to families on exposure reduction. Since starting active surveillance in May 2016, NC CLPPP identified 19 more children exposed to lead through take-home exposure from the two companies, totaling 35 linked children with confirmed BLL ≥5 µg/dL during 2012–2018. NC CLPPP continues to monitor these children quarterly and matches employee rosters annually to identify new cases.