Study: Lead in Flint kids’ blood drops to historic low

Karen Bouffard
The Detroit News
View Comments

The amount of lead in the blood of Flint’s children dropped to a historic low in 2016 after action was taken in response to the city’s water crisis, according to a University of Michigan study published Monday in the Journal of Pediatrics.

Researchers analyzed lead concentrations of 15,817 blood samples of Flint children 5 years old and younger over an 11 year period, including before, during and after the city’s use of corrosive Flint River water.

According to the study, the average blood level for Flint children reached an all-time low in 2016 of 1.15 micrograms per deciliter, decreasing from 2.33 in 2006. The average blood lead level in 2015, during the height of the city’s lead-tainted water crisis, was 1.3 micrograms per deciliter — up from 1.19 in 2014, when the city began using the Flint River as its municipal water source.

“There shouldn’t be a reaction such as ‘Oh, goodie, it’s the lowest levels ever in Flint, what a wonderful thing, let’s just back off now,” said lead author Hernan Gomez, an associate professor in the department of emergency medicine at UM, on Monday. “That would be just horrendous.

“Infrastructure issues clearly need to be addressed. There were a couple of silly decisions, the lack of (anti-corrosive chemicals) and the like, that were not carefully planned. I would expect a responsible government to fix the infrastructure that was damaged.”

The percentage of Flint children with blood lead levels over 5 micrograms per deciliter — the level at which the Centers for Disease Control and Prevention recommends public health actions — declined annually beginning in 2006, when 11.8 percent of kids tested had positive results. By 2013, positive lead tests reached a historic low of 2.2 percent.

After officials failed to properly treat Flint River water with anti-corrosive chemicals, the percentage of positive blood lead level tests inched upward to 3.3 percent in 2014 and to 3.7 percent in 2015.

Flint used river water from April 2014 until October 2015, when the city was moved back to Detroit’s system following an outbreak of Legionnaires’ cases and evidence of elevated levels of lead in the city’s children.

The percentage of positive tests declined to 3.2 percent in 2016 after the city brought in bottled drinking water and instructed residents to use filtered water for drinking and cooking. The city also began its efforts that year to remove residential lead service lines. Through 2017, more than 6,200 properties have had their lines replaced.

According to Gomez, the results show that corrective actions taken in Flint significantly reduced the number of Flint children with high blood lead levels. Gomez, also a pediatrician and emergency doctor at Flint’s Hurley Medical Center, said those efforts should continue.

“It’s unacceptable that any child was exposed to drinking water with elevated lead concentrations,” Gomez said.” There is no known safe blood level of lead, and the ultimate public health goal is for children to have zero amounts of lead in their system.”

Dr. Mona Hanna-Attisha, director of the Pediatric Public Health Initiative and Pediatric Residency Program at Flint’s Hurley Medical Center, said the study’s findings are consistent with other research. But data from lead screening tests “massively underestimate” the number of Flint children exposed during the crisis.

Lead screening rates were extremely low in Flint prior to the water crisis, with only 40 percent of children on Medicaid being tested, she said. Since the lead poisoning problem was underestimated, many Flint parents didn’t think they needed to get their children tested.

Among children who were tested, some would have gotten negative results, even if they were exposed to lead, she added. That’s because blood tests can only detect lead if the child was exposed within the previous 28 days.

Hanna-Attisha’s own research uncovered the problem of lead poisoning in Flint children following the water switch. High blood lead levels can lead to developmental problems, behavioral disorders and learning difficulties, so the exposure in any child is concerning, she said.

“Lead is bad, all sources are bad, even though we had higher levels before, it's still bad,” Hanna-Attisha said Monday. “I feel I need to say it one million times in one million different ways.”

View Comments