Although national and local policies have reduced the prevalence of lead poisoning in the United States, severe cases still occur. Whereas, exposures at blood lead levels (BLLs) as low as 5 µg/dL have been associated with long-term irreversible cognitive deficits, more severe exposures at BLLs ≥45 µg/dL can result in organ damage and death. In a new study scheduled for publication in The Journal of Pediatrics, researchers identified sources of exposure and assessed outcomes for children with severe lead poisoning.
Dr. Jacqueline Ehrlich and researchers from the New York City Department of Health and Mental Hygiene collected data from children under 18 years of age who were found to have BLLs ≥45 µg/dL. Risk assessment questionnaires provided information on the children's behaviors, recent home improvements, and use of imported products. During home visits, inspectors measured the lead content of painted surfaces and healthcare providers were advised to obtain abdominal X-rays to check for recent ingestion of leaded material before starting treatments. According to Dr. Ehrlich, "Understanding the incidence, sources, and treatment outcomes can promote timely identification of cases, as well as help inform clinical practice and public health policy."
Between 2004 and 2010, a total of 145 children in New York City were identified with BLLs ≥45 µg/dL. The median age at identification was 3.8 years, and it took a median of 3.2 years for the BLLs to decline to <10 µg/dL. Major risk factors for severe lead poisoning included: eating paint (36%), spending time outside the United States (34%), having a developmental delay (27%), being born outside the United States (14%), being of Pakistani descent (12%), and having sickle-cell disease (4%). When compared with the age-standardized New York City population, children with BLLs ≥45 µg/dL were more likely to be Asian or black and live in housing built before 1940.
Even though many of the risk factors found in this study are well known, two previously unfamiliar ones, Asian ethnicity (specifically from Pakistan) and sickle-cell disease, were found. Dr. Ehrlich notes, "Physicians should be especially vigilant in certain at-risk populations, including children who eat paint, spend time outside the U.S. (particularly in Pakistan), use imported products, or have developmental delays of sickle-cell disease." Recognizing these risk factors could facilitate timely identification and treatment of lead poisoning.