Here is an online article from Wired.com

This environmental health tragedy is VERY serious in this day and age.

This is relevant to gene x environment interactions, … because, without a doubt, given the same dose of lead (in utero, infancy, or childhood) the response (risk of permanent damage to the central nervous system and kidneys especially) will vary depending on the genetic make-up of each individual.


IT DIDN’T TAKE long for Mona Hanna-Attisha to realize that something was wrong with the water in Flint, Michigan. In April 2014 the city switched its water source, from Lake Huron to the Flint River, in order to save money during the construction of a new Huron pipeline. “Patients’ families were complaining right away,” remembers Hanna-Attisha, a pediatrician at Hurley Children’s Hospital in Flint and a professor at Michigan State University’s medical school. “The water was brown. It looked gross, and it tasted gross.”

But it turned out that the most dangerous substance in Flint’s water couldn’t be seen or tasted: lead. Lead (Pb) metal exposure can lead to kidney problems and other health issues in adults, but it’s particularly dangerous for young children, whose growing bodies—and brains—absorb more of the chemical. Children exposed to lead often end up with developmental problems that can plague them for the rest of their lives. The same goes for children whose mothers were exposed when they were still in the womb. Even those children’s grandchildren might be affected, since lead exposure has an epigenetic effect that can be passed down for generations.

“Lead in the water—that motivates every pediatrician to freak out,” Hanna-Attisha says. It should. Decades of research have shown that lead exposure is virtually untreatable. And once it causes neurological damage—well, that’s irreversible.

Although the CDC says there is no safe level of lead, public health officials really start to worry once a child reaches five micrograms of lead per tenth-of-a-liter of blood (or 5 µg/dL, in science speak). So when Hanna-Attisha heard that scientists had found high levels of lead in Flint’s water in September 2015, she went back and looked at the city’s records of children’s blood lead levels. “In the entire city of Flint, the percentage of kids with elevated lead levels doubled” after the switch to river water, she says. In a couple of particularly poor neighborhoods, they tripled. “This is a preventable, population wide disaster,” says Hanna-Attisha.

There is a way to remove lead and other heavy metals from the body. It’s called chelation therapy. Basically, you take a drug that binds with lead to form a water-soluble molecule. That allows your kidneys to process the lead and excrete it in your urine, so it doesn’t hang out in your body and get stored in your bones. “Chelation therapy has saved the lives of thousands of children in the US and around the world,” says Kim Dietrich, an epidemiologist at University of Cincinnati College of Medicine. But doctors only use it in very severe cases of lead poisoning, when blood levels climb above 44 µg/dL and the immediate physiological effects are life-threatening.

But what about for kids like the ones in Flint? They weren’t going to die within hours from acute lead poisoning, but they could have neurological problems for the rest of their lives. Could chelation therapy stop the damage?

Between 1994 and 2003, Dietrich did a study to find out. Some children—one and two-year-olds—who came to their doctors with blood lead levels between 20 and 44 µg/dL got a placebo and others got chelation therapy. Dietrich and his team then followed up with them when they were five, and again when they were seven. Although the chelation therapy successfully reduced the blood lead levels of the treatment group at the time, “the active drug group was no better in terms of their neurobehavioral development or neurological development, or in any other areas of health that we examined, than the group that received placebo,” Dietrich says. In other words: It didn’t work. Kids treated with chelation therapy were just as likely to have developmental delays and cognitive problems as the kids who got the placebo.

There’s no pill for lead,” at least not for cases like Flint, says Hanna-Attisha. What there is—well, it’s not easy, it’s not sexy, and it’s not fast. The way to treat lead poisoning after the fact is to get kids the services they should have had anyway. Access to early childhood education, for example, is proven to help kids with developmental delays catch up with their peers. (There’s never been a clinical trial about the effects of early education on lead-exposed children specifically, because creating a control group that didn’t get the treatment, i.e. an education, would be beyond unethical.) Diets rich in iron, calcium, and vitamin C can help mitigate some of lead’s worst effects. And regular pediatrician visits make sure families catch any neurological problems early. “The sooner we get them services, the better the outcomes,” Hanna-Attisha says.

Of course, quality schools, doctors, and grocery stores are all services that poor communities like Flint often lack. If the city couldn’t even afford safe water, how is it supposed to pay for universal preschool? I asked Hanna-Attisha if she thought Flint’s kids were really going to get all the services they need to overcome their lead exposure. She said she’s trying to turn her “anger into optimism,” especially since the situation in Flint is so egregious that it’s getting a lot of attention from both the media and policy makers. Today, Hanna-Attisha’s hospital is announcing a new public health initiative intended to make sure kids who have been exposed to lead see doctors and get the help they need. The Community Foundation of Greater Flint has set up a fund you can donate to that will focus on making sure the city’s kids have access to healthy food and early education. And perhaps most important of all, Flint has already switched back to Lake Huron water, which should prevent more children from becoming exposed.

Still, lead exposure is a lifelong issue, and as Dietrich’s chelation study underscored, there’s no one-and-done solution. No matter how much money the community collects or how many new preschools open in Flint, the city is in for public health challenge that could last generations, thanks to lead’s epigenetic effects. There’s only one way for Flint to treat its lead poisoning problem: become the city its citizens always deserved.

This entry was posted in Toxicology. Bookmark the permalink.