Blood lead levels in Flint, Mich., spiked when children were exposed to contaminated water but still were lower than they had been several years prior, according to a new study.
“These findings suggest that even when taking into account exposure to corrosive Flint water, long term public health efforts to reduce lead exposure in the community have been largely effective,” lead author Hernan F. Gomez, M.D., a medical toxicologist and pediatrician at Michigan Medicine, said in a news release.
Flint officials began using Flint River water on April 25, 2014, but stopped after Oct. 15, 2015, due to an investigation by Mona Hanna-Attisha, M.D., M.P.H., FAAP, and her colleagues that found increases in children’s blood lead levels (BLLs). Lead exposure has been associated with health, learning and behavior problems, and no amount is considered safe.
Researchers in this new study set out to look at children’s blood levels before, during and after the switch. They published their findings in "Blood Lead Levels of Children in Flint, Michigan: 2006-2016” (Gomez HF, et al. J Pediatr. March 26, 2018, https://www.sciencedirect.com/science/article/pii/S0022347617317584).
Upon analyzing data on 15,817 children ages 5 years and younger, they found 11.8% had BLLs of 5 micrograms per deciliter (µg/dL) or higher in 2006, which dropped to 3.2% in 2016, a 73% decrease.
During that same period, the geometric mean decreased from 2.33 µg/dL to 1.15 µg/dL, a nearly 51% drop.
Two spikes occurred during that decade. The first — from 1.75 µg/dL in 2010 to 1.87 µg/dL in 2011 — was deemed random by the authors. The second occurred during the water switch when levels rose from 1.19 µg/dL in 2014 to 1.30 µg/dL in 2015.
“We found that the increased blood lead levels of Flint children during the water crisis — while very concerning — was not higher than that found in years prior to 2013,” Dr. Gomez said.
However, he noted exposure to drinking water with elevated lead concentrations is “unacceptable.” The study also pointed to several Michigan counties that had even higher percentages of children with elevated BLLs.
“… public health officials, legislators, and clinicians should continue efforts and allocate appropriate resources to continue reducing environmental lead exposure of children in all communities at risk,” they wrote.