Difference from earlier surveys credited to cleanup efforts, more accurate data
A new investigation by researchers from the University of Texas Medical Branch at Galveston and the Galveston County Health District has shown that blood lead levels in one- and two-year-old children in Galveston are at or below state and national averages — a dramatic contrast with previous studies that appeared to show a high rate of elevated blood lead levels among Galveston children.
Using blood lead level data from 1,430 electronic medical records documenting routine checkups at UTMB Health from 2006 to 2008, the team found that 1.12 percent of children in their sample exceeded the blood lead level recommended by the Centers for Disease Control and Prevention as a threshold for response by medical and public health authorities. The rate of elevated blood lead levels was higher among Galveston Island children (1.48 percent) than those from the mainland (0.5 percent), but still very close to the national (1.4 percent) and state (1.3 percent) averages.
The study was conducted by the LEAST Lead Initiative, a project created by a coalition of UTMB departments, community leaders, the Galveston County Health District and the Galveston Independent School District in response to issues raised by Galveston’s Childhood Lead Poisoning Prevention Task Force.
In a report documenting the investigation and their other efforts (“Childhood Lead Exposure in Galveston, Texas, 2006-2008,” available at http://www.utmb.edu/cehd/index.html ) the LEAST Lead Initiative researchers attribute the difference between their results and those produced by earlier investigations to two main factors. First, Galveston has undertaken significant measures to reduce lead exposure since data was collected for the other studies — conducting major lead cleanups focused on the large number of homes in the city built before lead-based house paint was banned in 1978, and mounting lead abatement programs in public housing developments and playgrounds. Second, rigorous data collection methods allowed the LEAST team to produce a more accurate depiction of current blood lead levels in Galveston children.
“This is a snapshot of what’s actually happening with childhood lead exposure in Galveston,” said Alexandra (Lexi) Nolen, director of the UTMB Center to Eliminate Health Disparities and an author of the report. “Our results are drawn from a complete set of institutional data, and that enabled us to generate a very clear picture of blood lead levels — one that shows that in terms of actual exposure of children, Galveston is quite similar to the rest of the state and nation: not perfect, but much better than what was previously reported.”
Lead toxicity is a particular concern for children under six, in whom even low blood lead levels have been linked to permanent neurological damage, behavioral disorders and other long-term health problems. Lead levels in the American population have declined steadily in recent decades, thanks in part to the federal ban on leaded gasoline. Other sources of lead exposure persist, however — most importantly lead-based paint associated with older homes, a major concern in Galveston, where most housing was built prior to the adoption of lead-free paint.
The vast majority of children in the LEAST lead samples had blood lead levels that were less than half those designated by the CDC as “elevated” — 10 micrograms of lead per deciliter of blood. But recent work has demonstrated that even such “sub-threshold” levels can be cause for concern, and one of the goals of the LEAST effort was to determine whether Galveston children were being exposed to potentially harmful levels of lead that fall below the current CDC standard.
“Research has shown that even sub-threshold blood lead levels can measurably reduce IQ,” said Meredith Masel, program manager for the Center to Eliminate Health Disparities and an author of the report. “Unfortunately, the labs are inconsistent in how they report levels below 10 micrograms per deciliter — sometimes they send back a number, and sometimes they just say that the result was under 10. That could be nine or two or zero, and we don’t know how to interpret that.”
To improve lead testing, monitoring and reporting in Galveston, the report’s authors recommended improving methods for reporting sub-threshold blood lead levels and reviewing sub-threshold lead level policy. Other suggestions included changes to UTMB Health’s electronic medical record system to make lead level records more easily available for patient care, reporting to state agencies and future analysis and monitoring; better information coordination between UTMB Health, the Galveston County Health District and the Texas Department of State Health Services; and updated training for health care providers on state guidelines, new research, new electronic medical record system features and lead-related policy changes.
“We’ve presented these recommendations to the UTMB administration and their responses are provided in the report,” Nolen said. “They’ve been very willing to work on these issues, which I think is a great credit to them, because it’s very important to the community that the institution be able to monitor this issue.”
Other authors contributing to the report include Associate Professor Sharon Petronella-Croisant and Professor Jonathan Ward of UTMB’s Department of Preventive Medicine and Community Health; Dr. Christine Turley of UTMB’s Department of Pediatrics; John Sullivan, director of public forum and toxics assistance for the UTMB National Institute of Environmental Health Sciences Center for Environmental Toxicology and the Sealy Center for Environmental Toxicology; and Dana Beckham, chief epidemiologist for the Galveston County Health District.
The LEAST Lead Initiative received funding from the Mitchell Foundation, the Harris and Eliza Kempner Fund, the Mary Moody Northen Endowment and the Moody Foundation. “LEAST” stands for “Laboratory analysis of blood lead level samples, Education for parents to make home environments lead-safe, Administer treatment for children with elevated lead levels, Studies based on empirical evidence and Tracking of health system functioning.”