Burgess COMMENTARY

Peter Burgess

Yvette CabreraFollow Investigative reporter at ThinkProgress: criminal justice, immigration & environmental issues. Contact: ycabrera@thinkprogress.org Jul 15 The lead crisis: Tackling an invisible, dangerous neurotoxin Community awareness and action are key to enacting solutions Artwork by Diana Ofosu As Howard Mielke makes his way down the streets of his tree-lined New Orleans neighborhood toward the Bayou St. John, his walk is careful and deliberate. The canal’s waters are calm and glassy, reflecting the wisps of clouds above, and revealing none of the dangers below where alligators sometimes lurk. Mielke is a man of habits and, as he does every workday, he makes his way across the canal to the bright red streetcar that awaits the first of the morning’s commuters near the lush gardens of New Orleans’ City Park. At exactly five minutes to 8 a.m. on a steamy September morning, he boards the streetcar and a few minutes later it lurches toward his downtown office at the Tulane University School of Medicine. It’s the briefest of trips for Mielke on a journey that has stretched decades to try to help save the country’s children from a danger hidden in the soil on which they play. Tulane University School of Medicine Professor Howard Mielke walks through his New Orleans neighborhood on his way to work. Mielke has studied the effects of lead on children’s health for decades. CREDIT: Daniel A. Anderson for ThinkProgress Mielke has spent four decades investigating the dangers of lead contamination in soil across the country — from Baltimore, Maryland to Minnesota’s Twin Cities to New Orleans, where he has geographically mapped lead soil levels over the course of 20 years. He is an urban geochemistry and health expert who teaches in the department of pharmacology at Tulane University’s School of Medicine. The result of his life’s work is spread across his office: from awards like the Katrina Heroes commemoration he received from New Orleans in 2015 to the 1984 photograph taped to a file cabinet showing Mielke testifying before the U.S. Senate. The words “Thanks Howard, with your help we’re ‘getting the lead out!’” are scribbled underneath, a note from former Sen. David Durenberger (R-MN). But Mielke has given the most prominent position on his office wall to a large, colorful map of New Orleans he created. It shows the median levels of lead in the city’s soil, illustrated in a range of reds. The highest lead levels, those greater than 1,000 parts per million, are a vibrant crimson—signaling danger. What’s illustrated so colorfully on the map is not visible to the human eye in the real world. “You’re always working with invisibles,” he said, pointing to the map, which is peppered with dots and triangles representing childcare play areas and public playgrounds. “The map — nobody sees this on the ground. You wander around, you don’t realize that there’s a mountain of lead downtown.” The map is the result of countless hours that he and his small team of research associates have poured into collecting dirt samples, testing for the presence of lead, and analyzing the results in order to create a map showing just how pervasively lead has contaminated soil in New Orleans. Tulane University School of Medicine Professor Howard Mielke rides a streetcar to work every day in New Orleans, where he has researched the effects of lead soil contamination on children for two decades. CREDIT: Daniel A. Anderson for ThinkProgress Mielke’s work, geographically mapping contaminated soil and documenting the effects on the blood lead levels of children who ingest or inhale these particles, confirms the predictions of a scientist who decades ago broke new ground on lead’s impact: Clair C. Patterson, a California Institute of Technology geochemist. Patterson pioneered techniques to measure lead levels. By measuring the accumulation of lead within Arctic ice-core samples, he discovered that tetraethyl lead additives in gasoline fuel had contributed significantly to the rise in atmospheric lead levels. “You wander around, you don’t realize that there’s a mountain of lead downtown.” In the 1960s and 1970s, Patterson also challenged the notion that existing levels of lead in the environment were normal, and argued that Americans’ blood lead levels were unsafe. His findings subsequently provided key evidence for environmental activists who sought to remove lead from gasoline and reduce emissions. In a 1980 report to the National Academy of Sciences, Patterson wrote that “Sometime in the near future it probably will be shown that the older urban areas of the United States have been rendered more or less uninhabitable by the millions of tons of poisonous industrial lead residues that have accumulated in cities during the past century.” Urban geochemistry and health expert Howard Mielke in his office at Tulane University School of Medicine in New Orleans where he teaches in the department of pharmacology. CREDIT: Daniel A. Anderson for ThinkProgress Patterson’s research was instrumental in the work that led the government to ban the lead additives, which significantly reduced lead gasoline emissions. But the battle was far from over. Decades of emissions left a dangerous legacy behind: large deposits of lead particles that remain in the soil today and continue to plague communities with a history of high-density traffic flow. “It’s a long story and it’s a continuing one, and it would be nice to have an ending to it,” said Mielke. Cleaning up a crisis Over the last decade, a growing body of scientific evidence has shown that the harmful effects of childhood lead exposure are far greater than previously thought. Today, the consensus among health experts is that there is no safe level of lead exposure. Studies have also shown that there is no type of intervention that is effective in lowering blood lead levels. In short, prevention is paramount. Yet the most effective approach to reducing childhood lead exposure — removing the lead from the environment — is a solution that has been largely ignored in favor of simply treating lead-exposed children first, then remediating the problem secondarily, said Mielke. “We can measure the environment, we can map cities, that’s within our grasp. It’s easy to undertake and do, but we’ve chosen instead to measure blood lead,” said Mielke. “We can measure the environment, we can map cities, that’s within our grasp…. we’ve chosen instead to measure blood lead.” Funding, however, is one of the biggest roadblocks to achieving primary prevention, which requires locating sources of exposure in the environment, plus screening communities with high risks of environmental exposure. “We know where the higher lead levels are going to be. This is not complicated. We know that in the deep interiors of our urban centers that’s where the problem really lies,” said the University of Cincinnati’s Kim Dietrich, director of epidemiology and biostatistics at the university’s College of Medicine. “Unfortunately, the resources don’t exist or the will probably doesn’t exist to go through these communities and test every home, every flat, every apartment for hazardous levels of lead,” said Dietrich. The preventative approach also requires pediatricians serving families in these areas to abide by the federal screening laws, said Dietrich. Federal law requires all Medicaid-enrolled children to be tested at 12 and 24 months for lead exposure, but previous research has shown compliance rates are low. Dietrich recommends targeted screening for children living in high-risk areas at the ages of 6 months, 12 months, 24 months and three years. His research has shown that blood lead levels start to rise when an infant begins to crawl. Lead screening “should be as done as faithfully as we try to do vaccination immunization. It should be part of the medical regimen for children,” said Dietrich. The cost of inaction versus the cost of cleanup The cost of lead remediation on a national scale would be significant. In New Orleans, the soil cleanup projects that Tulane University’s Howard Mielke has overseen target high-risk areas, such as childcare centers, by covering lead-contaminated soil with geotextile fabric and placing a six-inch clean river soil cap atop the fabric. The geotextile fabric costs about 2 cents per square foot, while the truckload of Mississippi river soil costs about $180 per project, which amounts to $2–4 per square foot. For a 1,000 square foot area the total cost is about $4,000 said Mielke. There are also soil removal methods known as “dig and haul” that are more expensive at $36 per square foot. The U.S. Environmental Protection Agency has used this technique to remove contaminated soil from urban areas, but at an urban soil workshop last fall, one EPA regional administrator noted the cost savings and effectiveness of Mielke’s approach. “It costs a ton of money to haul off soil and replace it with clean soil. Howard has done inches instead of feet, and there is no haul away. There is a ripple effect and it is amazing how much change can take place,” said EPA toxicologist Marc Stifelman, according to the meeting summary notes.