Researchers ignore lead in soil
They gave us four studies to prove their point. Guess what!
By Skip Schloming & Lenore Schloming
Lead agency hands over studies
We asked the experts on lead poisoning to prove us wrong. To prove it’s the paint, not the soil, that poisons children.
Give us studies, we said. They gave us studies.
Did their studies prove it’s paint? No.
Using the Freedom of Information Act, we asked Brad Prenney, director of Massachusetts’ Childhood Lead PoisoningPrevention Program (CLPPP), to give us copies of any scientific studies his agency “relied on as the basis for abatement” of interior lead paint.
After all, maybe the “experts” have evidence we haven’t seen.
The EPA studies we’ve seen say the real source is lead dust that children get on their hands and put in their mouths.
And where do they say this dust comes from? From the soil around homes, which children play in, track in, and which blows in through open windows, sending up lead dust levels and blood lead levels especially in summertime.
An important study (by Yaffe) used isotopic analysis to show that lead in interior household dust comes from lead in the soil outside the home, and definitely not from the paint inside. CLPPP did not send us this study!
The EPA tells parents that “lead-based paint that is in good condition is usually not a hazard.” (Emphasis added.)
All this says it’s a waste of time to delead paint inside homes. But, maybe CLPPP had a study that showed otherwise.
What we asked for
We asked CLPPP to send us “any scientific study you have relied on as the basis for abatement” that shows (1) that lead-contaminated dust is created by lead-painted window or door surfaces rubbing or bumping, (2) that lead dust on window sills or window wells comes from the windows and not from dust blowing in from outdoors, (3) that interior lead dust comes from interior lead paint and not from lead in the soil or exterior lead paint, (4) that children chew or “mouth” interior painted surfaces, and (5) that children get “pica” or any other disease causing them to chew or “mouth” paint on doors and woodwork. The Massachusetts deleading law is based on the belief that the children get lead poisoned by chewing woodwork and eating paint chips. We asked CLPPP for the proofs needed to justify the Mass law.
What they gave us
After questioning exactly what we meant by “relied on as the basis for abatement” (the plain, ordinary meaning, we said), CLPPP sent us four studies and said there is “an enormous body of research” on the topic. They must have sent us the best available.
We studied the studies. Here’s what we found.
None of the studies answered any of our questions. CLPPP did not send us any study showing how much dust windows or doors produce by rubbing and bumping. They did not send us a study that showed that lead dust in homes comes from paint in the home. There was no study about children with “pica” chewing woodwork and eating paint chips. If that’s the best they have, then they just don’t have any studies showing that the paint on windows, doors, woodwork or walls turns into dust, or that children really chew woodwork. These are beliefs — even myths — taken on faith, not scientific facts. What they gave us instead was studies that all agreed with the EPA studies that lead dust is the real problem, but did not study exactly where the dust came from.
Lead dust: from inside or outside?
How can you tell whether household lead dust is coming from inside — from opening and closing windows, slamming doors, chewing woodwork, deteriorating walls — or from outside — from soil getting tracked or blown in? All these things may have lead in them, but if they don’t turn into dust, it doesn’t matter. The critical question is: does the lead dust come from paint or soil? does paint turn into household dust more than soil does?
One clear way to tell where the lead dust comes from is by finding out what kind of lead is in it. That’s what isotopic analysis does. It identifies the different kinds of lead isotopes in all sorts of places: in dust, blood, interior paint, exterior paint, soil, air, gasoline, lead smelters, batteries.
The major study using isotopic analysis (Yaffe) showthe isotopes in household dust, children’s blood, and the soil around their homes were all the same! And definitely not the same as the isotopes in the interior paint.
CLPPP didn’t send us this study or any other isotopic study showing different results! One study they did send us even misquotes the Yaffee study, saying: “This elegant technique revealed that the isotopic ratio of the children’s blood was virtually identical to the ratio found in house dust and some of the paint.” They don’t report that Yaffe identified it as the exterior paint, not the interior. They don’t report that Yaffe said “the soil was contaminated by paint derived from the exterior surfaces” and “the children spent much time playing in the lead-contaminated soil.”
Instead, CLPPP sent us four studies focussed entirely on the effects of interior lead paint abatement. All the study authors acknowledge that lead dust is what elevates blood lead levels. They acknowledge that soil has lead in it. But they never, never, never ask where does the household lead dust come from: inside or outside? On blind faith, they assume the dust comes from interior paint. Ironically, by assuming it, they never prove it.
Study 1: Dust, dust, dust. Yes, but is it paint or soil?
This is not an original study, but a review of many other studies on household lead dust. It says: (1) There is a connection between household lead dust and elevated blood lead levels in children. (2) The smallest particles of lead get absorbed into the body much more easily than larger particles (paint chips). (3) Deleading is hazardous because it contaminates homes with small lead dust particles that go right through the filters of ordinary vacuum cleaners and right into a child’s bloodstream. That’s all, folks. Nothing showing that interior lead paint turns into dust.
Study 2: Abatement fails. Lead dust comes back.
Guess what. This thorough study found interior lead paint abatement did not work! All the lead dust came back!
The key finding of this 1990 study in the authors’ own words: “At six months [after abatement], lead dust levels were similar to, or greater than, their respective pre-abatement levels in both abatement groups.” The results are a disaster for the policy of removing paint inside the home.
This thorough study tested the lead dust levels in 71 dwellings before, immediately after, and six months after interior lead paint abatement, testing each dwelling an average of 44 times in 13 different locations. When old-fashioned deleading was done, lead dust levels zoomed up afterwards — 10 to 100 times higher than before deleading — showing how hazardous deleading can be. When workers carefully washed down dusty surfaces right after abatement with high-phosphate detergent, then dust levels went down. But they didn’t stay down.
Six months later, regardless of high or low dust levels immediately after abatement, the dust levels were right back to their pre-abatement levels.
Obviously, the dust must come from somewhere else. The authors mention several times that soil contributes lead to household dust. They mention that dust levels in their own study went up “significantly” in the summer when children spend more time outdoors. Do they admit that soil contaminated the dust in their study? No. The authors blind themselves to the outdoor source of dust and cling to the belief that it has to be the inside paint. They recommend “more extensive, if not complete, abatement of lead-paint on interior and exterior surfaces,” deciding they did not abate enough. Just like the true believers in communism who insist that Russian communism didn’t work because it wasn’t “true” communism!
Study 3: Just delead everything (and clean).
The disastrous results of their 1990 study led the same authors to study the more extensive abatement they urged. It was so expensive, they could do only six dwellings.
They went crazy and did everything to the hilt. Abate floor-to-ceiling, not just to five feet. Special emphasis on windows: delead completely or replace (something not done in their previous study). No dust-generating techniques, not even dry-scraping. Special emphasis on making all surfaces smooth and cleanable, especially floors. Super clean-up after abatement.
And guess what else they did! They talked to the occupants. When the families moved back in, they urged them to clean thoroughly, telling them especially about window sills and window wells.
Finally, success. Although lead dust levels still went up during abatement, as soon as they cleaned up, dust levels went down and stayed down for the nine months of the study.
Like true believers everywhere, the authors hang on to their belief and ignore the implications of the parents’ cleaning. If they had not told parents about cleaning and just did their super-abatement, they would have proof (if the dust levels stayed down) that interior lead paint produces lead dust and abatement stops it. But the parents were cleaning. As other studies show, household lead dust comes from soil and cleaning effectively stops it. If so, the parents were cleaning up dust from outdoors and abating the interior paint was useless. The paint wasn’t producing dust.
Study 4: Housing condition, yes. But what housing condition?
The same failure happens again in this 1985 study which tracked children when they left the hospital after chelation therapy. Chelation brought their high lead levels down low and the researchers tracked what happened when they went home to different types of housing.
Children who went back to “lead-free” public housing had lower lead levels than children who went back to “older housing.”
Surprise! The older housing had been deleaded! Once again, interior paint is removed, but the dust comes back. Do the researchers give up on deleading? No. As in the previous studies, they stick to the belief that interior paint turns to dust and conclude that the deleading had been done “partially” or “incompletely.” Meanwhile, they blind themselves to the outdoors, to the yards and soil around the housing which are part of a child’s environment, part of “housing condition.” Public housing usually has black-topped or concreted yards. Older housing, especially poor housing, often has untended bare-dirt yards. That difference could easily explain why deleaded older homes got recontaminated with lead dust — from the lead in the soil outside, as other research shows.
Blind to soil as a source of lead, all these researchers leave children exposed to lead poisoning and drive up the cost of housing by enforcing interior lead paint abatement that their own studies repeatedly show is completely ineffective and hazardous.
The four CLPPP studies are: Chisolm, Mellits, & Quaskey, “The Relationship between the Level of Lead Absorption in Children and the Age, Type, and Condition of Housing,” Environmental Research, 1985; Chisolm, “Toxicology of Exposure to Lead: The Role of Particulate Lead,” lecture, Johns Hopkins University School of Medicine, 1987; Farfel & Chisolm, “Health and Environmental Outcomes of Traditional and Modified Practices for Abatement of Residential Lead-Based Paint,” American Journal of Public Health, 1990; Farfel & Chisolm, “An Evaluation of Experimental Practices for Abatement of Residential Lead-Based Paint: Report on a Pilot Project,” Experimental Research, 1991.
Skip Schloming has a Ph.D. in Sociology from Brandeis University. Lenore Schloming has a Master’s Degree in Psychology from Boston University, and has done advanced graduate work towards the Ph.D. degree at Harvard and Brandeis Universities. Unader the name Lenore Monello, she published research at the Harvard School of Public Health with the late Dr. Jean Mayer, former president of Tufts University.
Archaic deleading method persists
Researchers don’t study paint chips, they study dust. Yet paint chips remain the heart of deleading today, the 50-year-old practice of removing intact lead paint from woodwork, not because paint turns into dust, but children might chew it.
One study sent us by CLPPP virtually admits the procedure is archaic. Abatement procedures developed around 1950, it says, were “based on the idea that only through repetitive ingestion of paint chips” could a child get poisoned. This, the study says, “provides the official rationale” for removing intact lead paint from “biting surfaces” up to four or five feet high. Critically, it says: “such traditional procedures do not take into account newer data which show clearly that lead in dust and soil are most important sources of lead for children.”
Around 1950, blood lead levels were on the rise, in response, no doubt, to the increasing national consumption of leaded gasoline. Post-war America was, after all, the big boom in automobile production, a car for every American family.
At the time, however, officials could see one and only one source: paint chips eaten by children. They couldn’t see the lead dust on children’s hands, in the air or in soil contaminated by exterior paint or auto exhaust.
So the first attempts to delead aimed at paint chips. Officials made owners remove the paint on woodwork any way they could — torch, heat gun, power sander — up to four or five feet high, unaware of the huge dust they were generating.
The method was a disaster. Children were getting repoisoned in deleaded homes. Gradually, officials realized the critical role of lead dust, not only from deleading itself, but as a primary source in the environment, especially soil.
The shift in focus from paint chips to lead dust is reflected in all four studies CLPPP sent us. One study is subtitled: “The role of particulate lead.” It concludes: “Dust and soils are major environmental sources of lead for children.” No mention of paint chips. “The major route of entry is the gastrointestinal route in conjunction with normal hand-to-mouth activity, such as thumb and finger sucking and the mouthing of toys.” No mention of children chewing woodwork.
Another study: “Ingestion of lead-contaminated house dust via repetitive hand-to-mouth activity is a major route of entry of lead into preschool children.” Dust, not paint chips.
And another critical new fact: the finer the dust, the easier it gets absorbed into children’s bodies. Absorption is “highly efficient” when the particles are “too small to be trapped by the ordinary household vacuum cleaner.”
When officials around 1950 fixed their minds on paint chips, they did not realize the heavy load children were getting from environmental lead dust. And despite dramatic declines in lead levels since the 1980s when lead was taken out of gasoline, they still haven’t changed their minds. Today, 50 years later, the dry-scraping of intact lead paint remains the cornerstone of lead paint abatement. Crude. Hazardous. Costly. And no research supports it. The one approach that stops dust and chips no matter what the source — cleanliness — is just too simple. It would eliminate their jobs. Paint chips are a mantra from the past, a ritual of deleading that survives on faith, out of historic habit, saving jobs.