The story of how epidemiology has revealed “silent epidemics” in children, and how the Trump administration is systematically denigrating that child-centric science, begins and ends with lead poisoning. In 1979, in The New England Journal of Medicine, Harvard scientist Herbert L. Needleman published the results of the first study laying out the public-health implications of minuscule lead exposures — cognitive delays, behavioral anomalies, and lower IQ. Those results highlighted a debate that has roiled environmental science ever since: Epidemiology had revealed that low levels of lead exposure caused brain damage in children, whereas most traditional toxicology experiments — conducted on animals — had not.

After Needleman’s work, laws requiring reductions of lead in gasoline and paint led to dramatic declines in the amount of lead in the blood of virtually every American child. The Flint water crisis notwithstanding, reduction of environmental lead is widely considered one of the public-health triumphs of the past half-century. But Needleman paid dearly for it.

Gasoline and chemical companies like E.I. DuPont, Dutch Shell, and the Ethyl Corporation of America attacked the lead studies as inconclusive and poorly conducted; one scientist allied with the gasoline industry argued that the loss of IQ in children was due not to lead but to their parents’ low IQs. Needleman, who had moved to the University of Pittsburgh, later faced allegations of scientific misconduct from industry-associated researchers, prompting a two-year investigation by the National Institutes of Health, in which he was ultimately exonerated. In a bid for “transparency,” recalled Philip Landrigan, who headed children’s environmental health research at Mount Sinai School of Medicine for three decades, lead-industry representatives gained access to Needleman’s raw data and tried to use it to discredit his findings.

The lead findings were debated for more than two decades, and Needleman, denied access to his own research files for two years, emerged a bruised and embittered figure. In a 1992 article for the journal Pediatrics chronicling his travails, Needleman made clear he felt like the victim of a witch hunt; the title was “Salem Comes to the National Institutes of Health.” “Needleman was hounded,” said Lynn R. Goldman, dean of the Milken Institute School of Public Health at George Washington University. “But by the time it was all done, there were a dozen other studies showing exactly the same thing.” By 2012, the Centers for Disease Control and Prevention concluded there was no safe level of lead exposure, in part because its deleterious effects were irreversible.

InApril 1979, in the same week the New England Journal paper on lead poisoning came out, Eskenazi interviewed with Needleman for a job at Harvard. Eskenazi — a proud alumna of Flushing High School, Queens College, and Woodstock Nation (she attributes her original interest in neuropsychology to watching a young man at the music festival who dove headfirst into the pavement while tripping) — had just gotten a Ph.D. at the City University of New York, and one of her first research projects focused on lead. She didn’t get the job, but she and a new generation of environmental epidemiologists considered Needleman’s paper revolutionary. “It was like the first really good study to do what we were doing,” she recalls.

Eskenazi went on to join the faculty at UC Berkeley. In 1998, the National Institute of Environmental Health Sciences and the EPA began to fund ambitious research projects on children’s health, and her CHAMACOS study was among the first. The Berkeley researchers chose the Salinas Valley, which generates some $4.4 billion worth of lettuce, produce, and fruit each year, in large part because the mild, Mediterranean-like weather extends the growing season to 11 months. “We might lose families more easily in the Central Valley, whereas in the Salinas Valley they were more likely to stay put,” Eskenazi explains. As is standard in human-subject research, the Berkeley group baked in absolute privacy protections, including a “certificate of confidentiality” from the NIH pledging that the researchers could not “be compelled to reveal to anyone outside of the study the identity of study participants or information about them.” By 1999, the group had recruited 601 pregnant women to join the study; in 2000, the first children were born.

Since then, the Berkeley group has collected upwards of 350,000 biological and environmental samples — blood, urine, breast milk, saliva, and even household dust — from participants and has published more than 150 papers on the health effects on children of environmental toxins, including elevated levels of organophosphate (or OP) pesticides, which account for roughly 70 percent of all pesticide use in the U.S. There was good reason to study OP pesticides: They block an enzyme in nerve cells, essentially causing a synaptic stutter of hyperstimulation. That nervous-system frenzy makes for a highly effective insecticide, but in animal experiments, researchers have shown that this class of chemicals disrupts the formation and proper function of synapses, which are crucial to brain function. The Berkeley group found an association between in-utero exposure to OP pesticides and adverse neurological effects, including loss of IQ, cognitive deficits, behavioral issues like lack of attention, and respiratory problems. The effects are long-lasting, Eskenazi said, “from early age into the teens.”

Other research groups from that era, funded by both the NIEHS and the EPA, have reported similar findings. As any savvy consumer of medical news knows, correlation does not equal causation, and single studies should be viewed with caution, but as Eskenazi and others noted in a commentary published last fall, 26 of 27 studies have found a link between OP-pesticide exposure and adverse neurological effects in children. As Harvard’s Bellinger put it, “What’s important is the weight of evidence that accumulates, study after study … If all that kind of evidence together seems to be telling a consistent story, then I think the inference of causality becomes progressively more tenable.”

Studies relying on brain imaging to show the effects of environmental toxins on a child’s neurological development have only reinforced that link. In 1997, Virginia Rauh, deputy director of the Columbia Center for Children’s Environmental Health, and her colleagues began studying the prenatal effects of exposure to airborne pollutants on a group of pregnant women who lived in Washington Heights, central Harlem, and the South Bronx. Part of their study focused on chlorpyrifos. It is the most widely used insecticide in the country, according to the EPA, even though its use has declined since Rauh and Eskenazi began their studies; farmers use it on everything from Georgia peaches and California tree nuts to Kansas corn and Christmas trees grown in Oregon. The women in the Columbia study, mostly African-American or of Dominican ancestry, encountered chlorpyrifos because it was also widely used at the time as the active ingredient in household insecticides, including Raid. EPA scientists became so concerned about the possible health effects that in 2000 the agency began to phase in a ban on most residential uses of the chemical.

The Columbia group has followed approximately 370 children who were born to women exposed during pregnancy. Every few years, they bring the children in for psychological and cognitive tests and, more recently, brain-imaging sessions with an MRI machine. In a series of papers, Rauh and her colleagues have documented a link between higher levels of exposure to chlorpyrifos in the womb and early cognitive and behavioral deficits. MRI images showed that children with the highest prenatal exposure had structural “anomalies” in parts of the brain involved in attention, language, and executive function; Rauh is reluctant to call them abnormalities, because no one knows exactly what they mean. But the study showed, Rauh says, “significant differences, years later, in structural characteristics of the brain” between kids who had high versus low pesticide exposure in the womb. In some cases, higher exposure to chlorpyrifos in the womb was linked to surprising changes in brain architecture: females exhibited structural features typical of the male brain and males exhibited features typical of female brains. More recently, the Columbia researchers have reported that about 40 percent of the children who had the highest exposures to chlorpyrifos in the womb exhibited “mild to moderate tremor” in at least one arm.

The insidious thing about environmental toxins is that they can turn up far from farm fields or cockroach-infested housing units. The National Health and Nutrition Examination Survey, a research project conducted by the CDC, has consistently detected the breakdown products of OP pesticides in the urine of a random sample of Americans. “It’s not like the exposures that the farmworkers are getting are so outside of the realm of possibility of the general U.S. citizen,” says Eskenazi. “They’re also getting exposure from residues in food, just like we are.” Chlorpyrifos, Rauh adds, is widely used on golf courses.

Atthe start of 2015, around the same time the tremor findings came out, Ruth Etzel, a pediatrician and international leader in children’s environmental health, became head of the EPA’s Office of Children’s Health Protection. Although this was a tiny 15-person office in a vast 15,000-employee bureaucracy, Etzel had the ear of top officials at the agency.
She had monthly one-on-one meetings with EPA administrator Gina McCarthy and weighed in on the robust, wide-open scientific debates McCarthy famously convened to reach consensus on safe health standards. Etzel soon found herself involved in the long-running debate about the proposed ban on chlorpyrifos.

In 2007, two public-interest groups petitioned the EPA to ban all uses of the pesticide, arguing that there was no safe level of exposure in food. That triggered a legitimate debate within the EPA about whether the agency should weigh epidemiological studies more heavily than animal testing to establish safe health standards. Chlorpyrifos emerged as the test case. EPA scientists and administrators concluded in November 2016 that the epidemiological findings out of Columbia, Berkeley, and elsewhere warranted a total ban on chlorpyrifos. “Everybody was in agreement that it should be banned,” Etzel recalled during several interviews last fall, “because the scientific data were so compelling. There were no dissenters at EPA that I’m aware of, at least not that were in our discussions.”

The whole process for determining health risks changed with the arrival of the Trump administration. Pruitt took over as EPA administrator in February 2017 and immediately struck a new tone: Industry had a more prominent presence (Dow, the manufacturer of chlorpyrifos, contributed $1 million to the Trump inauguration fund), and career staff were reduced to being spectators at Pruitt’s weekly staff meeting. “The nonpolitical people were just there to listen,” says Etzel, one of about 15 top-echelon career officials who attended the meetings. Secrecy was in, and science was out. Pruitt installed a $43,000 soundproof phone booth in his office, and security guards limited access to a long corridor on the third floor that led to the EPA administrator’s office, according to Elizabeth Southerland, who resigned in 2017 after 33 years at the agency and now consults with the Environmental Protection Network, an organization of former EPA employees. She said only political appointees were typically allowed to pass the Pruitt checkpoint. “Scientists just became irrelevant at the agency,” Southerland said, “because we were not allowed in the room where the decisions were being made.” The freeze-out extended to the Office of Children’s Health Protection; rather than having the ear of the EPA administrator, Etzel says, “the meetings stopped altogether.” Her supervision was reassigned to the acting deputy chief of staff, and she never again met one-on-one with the EPA administrator.

Pruitt’s reversal of the planned total ban on chlorpyrifos was an explicit repudiation of the epidemiological studies. “By reversing the previous administration’s steps to ban one of the most widely used pesticides in the world,” Pruitt said in announcing the decision, “we are returning to using sound science in decision-making — rather than predetermined results.” An EPA press release dismissed the peer-reviewed epidemiological findings as “novel and uncertain,” adding that “reliable data, overwhelming in both quantity and quality, contradicts the reliance on — and misapplication of” — the epidemiological studies.

Scientists just became irrelevant at the agency, because we were not allowed in the room where the decisions were being made.

Chemical and agricultural interests have long insisted that use of the pesticide is both safe and essential. DowDuPont, whose Dow AgroSciences division makes chlorpyrifos, cited “fundamental limitations” in epidemiological studies, and said the Berkeley and Columbia findings were “unreliable and not valid for purposes of regulatory decision-making,” according to a company spokesperson.
DowDupont says chlorpyrifos use is supported by “more than 4,000 studies and reports examining the product in terms of health, safety and the environment.” And Sonny Perdue, Trump’s secretary of the Department of Agriculture, alluded last fall to “significant flaws” in the EPA’s 2016 assessment of health risks, adding that “the available scientific evidence does not indicate the need for a total ban.” By contrast, the American Academy of Pediatrics says the evidence of chlorpyrifos’s risk to children is “unambiguous.”

“We were stunned,” Etzel says of Pruitt’s decision. “I was not consulted. Nobody in my office was consulted. We learned about the decision when we picked up the newspaper or turned on the radio that day.” The courts were stunned too. In August, a three-judge panel of the U.S. Court of Appeals for the Ninth Circuit ordered the agency to reinstate the total ban within 60 days. Earlier this month, the court granted the Trump administration’s request to rehear the case.

Despite the chlorpyrifos decision, Etzel, oddly, remained cautiously optimistic about the new EPA regime. “I’m a Midwesterner,” she says. “I look at the world through rose-colored glasses.” In a three-minute pitch to Pruitt, Etzel pushed the idea of an ambitious federal strategy to eliminate lead poisoning. An estimated 500,000 American children still have elevated levels of lead in their blood. “That is an epidemic in anybody’s book,” said David Jacobs, chief scientist for the National Center for Healthy Housing, “and requires urgent action.” Etzel had been co-chairing a multiagency presidential task force to develop just such a plan since 2016, and she felt Pruitt was genuinely interested in what he called a “war on lead.” In fact, he set a June 2018 deadline to present the government’s new lead strategy.

But events — including mounting pressure on the scandal-challenged Pruitt to resign — intervened. On July 5, Pruitt was gone, and Andrew Wheeler, a former coal-industry lobbyist who had served as Pruitt’s deputy, was installed as acting EPA administrator. As Etzel’s staff put it to her, “unusual things were happening.”

Inlate June, just before Pruitt’s resignation, Etzel and Eskenazi found themselves together at a scientific meeting in Taipei. Informally voicing the sentiments of the scientific community, Eskenazi implored Etzel not to quit her key regulatory post at the EPA. “We need you there,” she said. “We need you to protect the children.”

Etzel chuckles when I ask her if she recalls the conversation. “I do, I do,” she says, “because so many people felt like we needed to just stand up despite the guerrilla warfare and continue to say what needed to be done.”

Although things were “really tough,” she told Eskenazi, “I’m going to stay.”

And she did — though things only got tougher. EPA administrators, who had defended Pruitt’s $43,000 phone booth and $3.5 million taxpayer-supported security detail, began to question the staff of the Office of Children’s Health Protection in an apparent attempt, Etzel believes, to find financial irregularities within her department. During the summer, the employees responsible for travel expenses and grants in her office were called to the office of the administrator and, according to her, were “tormented” by the questioning. “Ruth, they’re after us,” one of her staffers told her. Another amended that impression: “I’m not sure they’re after us, but they’re after you!”

At the same time, progress on the federal lead initiative appeared to stall, according to Etzel, just as the plan was due to be finalized. The perception among other agencies in the presidential task force, she says, “was that EPA was holding it up. Nobody knew exactly why.” In early August, Etzel’s standing meeting with her supervisor were permanently canceled without explanation.

No sooner had Eskenazi returned to California from the Taiwan conference than she had her own issues with the EPA. On July 12, she received an email from someone in the EPA’s “Pesticide Re-Evaluation Division,” asking her to turn over her raw data from the CHAMACOS study; the EPA group wanted “to explore the uncertainty” about how pesticides affected developing brains. Eskenazi immediately referred the inquiry to University of California lawyers.

This request was not an isolated incident. In April 2018, resurrecting tactics from the Needleman era, Pruitt had announced a policy called Strengthening Transparency in Regulatory Science, which stipulated that no research could be used to establish health standards for EPA regulations unless the scientists made their data publicly available. “The era of secret science at EPA is coming to an end,” Pruitt declared at the time. (This tactic dates back to the Obama era: Beginning in 2010, the EPA — “spurred by industry,” according to an agency source — has repeatedly requested the Columbia group’s data; the university has, while working to accommodate the EPA’s request, repeatedly expressed concerns about compromising the confidentiality of study participants.)

Although the idea of transparency sounds reasonable, even desirable, scientists regarded the intent behind the EPA policy as “very misleading and very disingenuous,” according to Landrigan, who fought the lead wars of the 1980s before helping to set up the Office of Children’s Health Protection. “We have an old saying in epidemiology,” Etzel says. “ ‘If you torture the data long enough, it will confess.’ ” The real motive, Landrigan said, was “to reanalyze the data and try to come up with different conclusions than the original authors. Another aim, he said, would be to use the data to track down individual study subjects and try to get those people to change their stories. “This happened in the 1970s and 1980s during the lead wars,” he said. Lynn Goldman, the dean of the public health school at George Washington University, said, “The thing that is worrisome is that they’re doing it because they’re trying to destroy you.” And epidemiologists have been especially targeted, she said, because “often from epidemiology, we see that things are far more hazardous than the animal data would have predicted.”

The surrender of raw data is a particularly sensitive issue to researchers who study children’s health, because potential violations of privacy could strip away the anonymity of minors with intellectual disabilities, mental-health issues, or, in the case of the CHAMACOS study, immigration-related concerns. In addition to Eskenazi’s, two other research groups, both of which had reported links between pesticide exposure and neurodevelopmental deficits, received requests from the EPA to turn over their raw data during the summer. In Landrigan’s view, whether the scientists comply or not, the transparency policy — which is still under review by Wheeler — is a win for the Trump EPA in its attempt to exclude the epidemiological studies from influencing regulations. If the scientists submit their data, they’ll open it to attack; if they withhold it on privacy grounds, they will effectively give the agency an excuse to ignore evidence of harms to children when they consider regulations.

Four days after the data request from the EPA, Eskenazi received another bombshell: The office of the director of the NIH informed her that it would not be renewing her $7.5 million grant. She had only a month to secure new funding. She does not believe the NIH decision was politically motivated (an NIH spokesperson said that, “regrettably,” the Berkeley study did not meet the requirements of the grant), but the action stunned other researchers, who have described the CHAMACOS study as “groundbreaking” and “a national treasure.” “I don’t really know why they pulled the money,” Eskenazi says. “I lay awake a lot at night, wondering what it was all about.”

While Eskenazi scrambled to find new funding to keep the CHAMACOS study afloat, the Trump EPA spent much of August announcing deregulatory initiatives that appeased the fossil-fuel industry — and ignored the science suggesting that those policy changes would perpetuate harm to children.

On August 2, the Trump administration announced its intention to delay emissions standards for cars and light trucks, in effect sanctioning continued high levels of traffic-related air pollution; a growing body of evidence links exposure to it to respiratory problems, early signs of neurodegenerative disease, and even autism-spectrum disorder. On August 21, the Trump EPA opened the door to increased amounts of black carbon and small particulate matter in the air with a planned rollback of restrictions on pollution from coal-burning power plants; even the EPA’s own analysis predicts 1,400 more deaths annually due to the increased pollution that will result. And on August 29, the Trump administration took the first step in dismantling Obama-era regulations governing mercury emissions from power plants; scientists have known for decades that developing fetuses are especially susceptible to mercury poisoning. “What became crystal clear to me is that EPA knew full well, because of the robust scientific literature, that chlorpyrifos and mercury and lead were harming the next generation,” Etzel says. “And despite that full knowledge, they refused to take action.”

Etzel’s final battle on behalf of children’s health may have been over lead. An August 31 draft of the federal lead policy was circulated internally to members of the president’s task force. Etzel declines to discuss any specifics of the lead strategy, but this version represented a retreat from previous versions, according to a source who saw multiple drafts. It abandoned provisions Etzel had argued for, including specific goals for eliminating lead and a specific budget to accomplish those goals. Conspicuously missing were any new regulations.

Throughout August and September, Etzel sent weekly emails requesting a meeting with Wheeler to discuss the lead plan. She was repeatedly told Wheeler was not available. Then, on the morning of September 25, while the rest of the country was gripped by the imminent Brett Kavanaugh hearings, Etzel’s scheduler got a call from the acting deputy chief of staff’s office, requesting a meeting that afternoon. At 4 p.m., Helena Wooden-Aguilar walked in, paused to compliment one of Etzel’s office decorations — a wall hanging from Guatemala — and then slid a piece of paper across her desk. “I’m putting you on administrative leave,” she said. Wooden-Aguilar refused to give a reason. “Give me your keys,” she said, according to Etzel. “Give me your iPhone and your credit card and your badge. And then I’ll walk you out.” Two people who appeared to be security personnel were waiting in the hallway, and the three EPA officials escorted Etzel to the door. She is not allowed to communicate with any EPA employees, including her former staff, and she still has not been told, more than four months later, why she was so unceremoniously evicted from her office, although she is still being paid. (The EPA press office did not respond to requests for comment.)

At 5:21 p.m., barely an hour later and still in shock, Etzel fired off a plaintive email to Landrigan and other colleagues, describing what had happened. “I appear to be the ‘fall guy’ for their plan to ‘disappear’ the office of children’s health,” she wrote. First reported by BuzzFeed, the email went viral in the children’s-health community.

“Based on all the facts I can see, including the timing of the drafts, it really appears that putting Ruth Etzel on administrative leave was at least partially driven by a desire to remove her from the discussion on lead specifically,” said Tom Neltner of the Environmental Defense Fund, who is also on EPA’s Children’s Health Protection advisory committee. “They’d clearly taken steps backward in the August 31 version, then three weeks later she gets put on administrative leave. That’s about the time it takes for a bureaucratic organization to review it, recognize that Ruth would be vocal on the issue, and figure out a strategy to silence her.”

In late December, just before the government shutdown, the EPA released the president’s long-delayed lead-poisoning plan. The National Resources Defense Council called it a “lead balloon.” Neltner said the final document did not amount to a strategy at all. “From my perspective,” he said, “the plan goes backwards from where we were in 1999.”