War of words, science still rages over lead contamination in Flint

Karen Bouffard
The Detroit News
There is a debate over what threshold of lead levels in children's blood should be considered "lead poisoning" in the wake of the Flint water crisis.

Three years after Dr. Mona Hanna-Attisha faced down the state over elevated lead levels in Flint’s drinking water, debate is again raging over whether kids there were “poisoned” or simply “exposed” to the toxin. 

Physician colleagues at Hurley Medical Center, where Hanna-Attisha is director of the Pediatric Public Health Initiative, voted in May to banish the words “lead poisoned” to describe what happened after the city switched its water source to the Flint River in April 2014 as a money-saving measure. 

Gathered for their annual meeting, the Hurley doctors had just listened to a presentation by Dr. Hernan Gomez, a board certified toxicologist, pediatrician and emergency room doctor at Hurley. He argued that the increase in Flint children’s blood lead levels was not significant, and that the term “lead poisoning” stigmatizes an entire generation of Flint children.

"We know that lead is a powerful neurotoxicant, that there is no safe level ... that long-term exposure to low to moderate levels of lead is associated with decreased I.Q.s and other cognitive and behavioral problems, including criminal behavior," Gomez acknowledged in the a July op-ed piece in the New York Times, co-authored by University of Cincinnati's Kim Dietrich. 

“But there is no reason to expect that what happened for a year and a half in Flint will inevitably lead to such effects. The casual use of the word ‘poisoned,’ which suggests that the affected children are irreparably brain-damaged, is grossly inaccurate." 

For Hanna-Attisha, Gomez’s argument not only is déjà vu, reminiscent of the state's initial denial of lead contamination in Flint, but dangerous for its policy implications — a concern shared by some scientists and population health experts. 

"Lead levels have been coming down for the last few decades, so kids are no longer coming into our E.R.s seizing and comatose and dying because of acute ingestion," Hanna-Attisha said. "But at the same time, we have learned so much —and we now know about the population-level sub-clinical impact.

"What happens at a population level is even more damning in terms of the impact on cognition and behavior and all the life-course-altering trajectory."  

After more than a year of denials by state and city officials that the water was unfit for human consumption, Hanna-Attisha released in September 2015 her initial research that showed a statistically significant increase in the number of Flint kids with elevated blood levels after the water switch.

Together with community activists, the doctor was publicly scorned by state officials —the Department of Environmental Quality spokesman described her press conference as “near hysteria.” But the strength of her data ultimately forced a reckoning.

Flint returned to safe Detroit water in October 2015, a federal emergency was declared in January 2016, and the state and federal governments have invested — and continue to spend — hundreds of millions to repair the water system and mitigate the effects of lead on the city’s kids.

Gomez’s commentary followed the release of "The Poisoned City: Flint's Water and the American Urban Tragedy," a book by Metro Detroit writer Anna Clark. It coincided with release of Hanna-Attisha’s book, “What the Eyes Don’t See,” her scathing account of the mishandling of the Flint water crisis.

It also came in the midst of preliminary exams of Michigan Department of Health and Human Services Director Nick Lyon and Chief Medical Executive Eden Wells, who have been charged with involuntary manslaughter and other crimes related to the crisis. 

"It is very coincidentally coming up at a time when we have lots of investigations, class action lawsuits and criminal charges in terms of Flint, and the need for our long term-recovery," Hanna-Attisha said of Gomez's assertions. 

Mona Hanna-Attisha, ’98, MPH ’08: After Flint, Mich., switched its water source, Hanna-Attisha spearheaded a study that showed lead levels in young children nearly doubled. This prompted President Obama to declare a federal emergency in 2016 and Time magazine to name the Michigan State pediatrics professor/physician one of its 100 most influential people in the world.

Flint Mayor Karen Weaver said it defies reality to say Flint residents weren't poisoned by the lead in their water.

"An entire city was drinking lead-poisoned water for 18 months before the government stepped in to do anything," Weaver said. "We need not to downplay what happened here."

Conflicting studies

Hanna-Attisha and Gomez each studied children's blood lead levels in Flint before and after the water switch. Both found an increase in the number that were elevated.

Hanna-Attisha's initial study, later validated by the federal Centers for Disease Control and Prevention and confirmed by state data, compared the blood lead levels of Flint children in 2013 prior to the water switch with those during the same months in 2015 after the water switch. 

Prior to April 2014, the number of lead-exposed kids had been dropping in Flint and across the state.  After the switch, the percentage of children with elevated blood lead levels above the federal "reference level" of 5 micrograms per deciliter was nearly double.  Zip codes with the highest water-lead levels saw the greatest percentage increases.

Gomez looked at Flint children from 2006 though 2016 and found that the annual percentage of Flint children whose blood lead levels surpassed the reference level did increase — but "only" from 2.2 percent to 3.7 percent, after the water switch.  

“It is not possible, statistically speaking, to distinguish the increase that occurred at the height of the contamination crisis from other random variations over the previous decade,” he wrote in the Times commentary. 

Based on his research, Gomez concluded "the furor over this issue seems way out of proportion to the actual dangers to the children from lead exposure."

The CDC recommends medical treatment only for blood lead levels at or above 45 micrograms per deciliter, he noted. "Not a single child in Flint tested this high," said Gomez, who is an associate professor of emergency medicine at the University of Michigan.  

The CDC has not set a definitive level beyond which children are considered "poisoned," but states: ‘‘Even low levels of lead are harmful and are associated with decreased intelligence, impaired neuro-behavioral development, decreased stature and growth, and impaired hearing acuity."

Flint's tip of iceberg

The absence of high-lead-level kids was inconsequential to Hanna-Attisha, because she viewed the results as the tip of an iceberg that was impossible to see due to limitations in the data. 

The most vulnerable kids were infants who were fed powdered baby formula mixed with the city's tap water, she said. This group of children was never tested, since lead testing is required at 12 months and 24 months by the federal Medicaid program. About half of Medicaid kids were tested. 

Since lead dissipates from the blood stream within 28 days of exposure, those exposed early in infancy would have escaped detection, Hanna-Attisha said.

"Imagine me as a general pediatrician telling the parents of my children: 'OK, if you can’t breast feed, bottle feed using formula, not whole milk,'" said Dr. Lawrence Reynolds, a general pediatrician in Flint and a member of Gov. Rick Snyder's task force on the Flint crisis.

"And so they mix the formula every day, six to eight times a day, and feed their infant, and the water is lead contaminated."

Asked if he agrees that infants consuming water-mixed formula were most in danger of high levels of lead exposure, Gomez said, "(W)e currently don’t have any scientific research to support that."

Edwards: Reject 'poisoning' label

Marc Edwards, the Virginia Tech environmental scientist who identified the problem of lead in Flint's water system, said it's impossible to know if infants were exposed but went undetected.

Virginia Tech Professor Marc Edwards

Edwards agreed with Gomez that Flint children shouldn't be labeled as poisoned. The effects of lead exposure will be minimal for the average Flint child, he argued.

"I feel that some children were damaged irreparably, both physically and psychologically, but that telling the average child in Flint that they can’t learn because of what has occurred — that’s also wrong and tragic, in and of itself," Edwards said.

"I witnessed that myself. We went to Flint schools, I heard that from Flint children, I heard that from Flint parents. That has a horrible cost." 

To Hanna-Attisha,  Edwards' evidence of lead in the city's water supply should have been enough to launch an aggressive public response — regardless of how much was detected in children's blood. 

"That is where this crisis should have ended," she said."That’s what public health is all about. 

"It should not have been an emergency based on the blood levels — it should have been an emergency based on the water levels." 

Hanna-Attisha's study zoomed in on 1,746 Hurley Medical Center pediatric patients.  By contrast, Gomez's studied 15,817 blood lead levels of Flint children taken over 10 years.

Low exposure hurts IQ

Gomez's study provided more of an aerial view, said Bruce Lanphear, a professor in health sciences at Canada's Simon Fraser University in British Columbia and an internationally recognized expert on environmental neurotoxins.

"When you step back and look at a 10-year trend, you lose what happens to those younger children — and you lose what happened to those children who lived in neighborhoods who had much higher levels because that’s where the lead service lines were located," Lanphear said. 

Regardless, a huge body of scientific evidence accumulated over decades has demonstrated that even low-level lead exposure robs children of intelligence quotient points, he said. 

On average, children with blood lead levels greater than 5 micrograms per deciliter lose about six IQ points per child — a pretty sizable difference, Lanphear said.

The next strata down, children with blood lead lead levels between 2.1 and 5 micrograms per deciliter will lose about one-and-a-half IQ points each.  At levels below that, lead robs the average child of about half an IQ point. 

"So why even bother to worry about those? If you only focus on the half a million children in the United States who have a blood lead in excess of 5, you only preserve 3 million out of the 23 million IQ points lost —18 percent," Lanphear said.

"So even though fewer IQ points are lost per kid at lower blood lead levels, because there’s so many of those children, that’s where you lose the vast majority of IQ points." 

Lead exposure is most common in older urban areas where children also struggle with poverty, violence, parental incarceration and other challenges that can interfere with learning, Lanphear said.  

"Children who live in impoverished communities have a cumulative impact of a number of different risk factors — like lead, like pesticides, like second hand smoke, like poor diet perhaps, like poverty— and all of that adds up," Lanphear said. 

"It's like death by a thousand cuts."

Dr. Lawrence Reynolds, a Flint resident, talks about the Flint water crisis from a health, social, political and race perspective.

Reynolds, the Flint pediatrician, said the consequences will unfold over years as children encounter problems with reading, calculation, attention, memory or mood.

"So we should lie to them? " Reynolds asked. "And then what we start doing is blaming the victim.

"Our children are not the ones who need to be stigmatized. It is we the adults who were charged with taking care of them."