University at Buffalo: low blood lead levels linked to higher odds of strep throat in children
Analysis of medical records of more than 13,000 children found higher odds of strep throat even at blood lead levels below the CDC action threshold, the authors report.
Even low levels of lead exposure are associated with a greater risk of strep throat in children, according to researchers at the University at Buffalo, as reported by EurekAlert eurekalert.org
EurekAlerteurekalert.orgOpen source ↗. The team examined medical record data on more than 13,000 children aged 14 or younger in Philadelphia, Pennsylvania, from 2010-20
eurekalert.org
EurekAlerteurekalert.orgOpen source ↗. Lead exposure data came from routine blood lead screening, and the records were checked for a clinical diagnosis of strep throat or croup.
Strep risk by blood lead level
Children with blood lead concentration under 1 microgram per deciliter, which is below public health intervention thresholds, served as the comparison group. Children with levels between 1 and 3.4 micrograms per deciliter had about 2.5 times the odds of being diagnosed with strep eurekalert.org
EurekAlerteurekalert.orgOpen source ↗. Those at or above 3.5 micrograms per deciliter, the Centers for Disease Control and Prevention threshold for taking public health action, had about 2.7 times the odds
eurekalert.org
EurekAlerteurekalert.orgOpen source ↗.
Higher lead concentrations were also associated with more frequent strep diagnoses. The researchers found no clear association between lead exposure and croup.
Immune system and housing context
The study, "Environmental lead exposure and clinical infectious respiratory disease in a sample of urban and disadvantaged children," was published in the Journal of Exposure Science and Environmental Epidemiology on Sept. 19. According to the authors, environmental lead exposure in children can adversely affect the development and maturation of the immune system and increase susceptibility to infectious respiratory illnesses. Scientific evidence on childhood respiratory outcomes linked to lead exposure remains inconclusive.
The effects were evident even below the blood lead action level set by the CDC. That value is based on the blood lead concentrations of the top 97.5% of children in the United States. It is meant to alert clinicians to increase observation and potentially recommend remediation of lead exposure in the home, but it does not have any health indications.
Corresponding author Marina Oktapodas Feiler said that homes in many older cities have historical lead paint that can chip, and that dust and deteriorating windows are especially problematic. She added that renters and people with lower incomes are disproportionately affected because they cannot maintain homes or carry out renovations that remove lead.
