A press release on EurekAlert caught my eye because it looked suspicious. The headline: “Children living near toxic waste sites experience higher blood lead levels resulting in lower IQ.” That assertive headline implies a rigorous study that tested the blood lead levels of many children, but, as we will see, the assertion is an assumption based on computer modeling, not testing.

We often see ominous headlines similar to the one above in the mainstream media. They can cause great concern. But it pays to look at the details. The headline is qualified in the first sentence of the press release with the phrase “may experience higher blood lead levels” but many of the media reports went with the headline. This headline came from a press release by the  Mount Sinai School of Medicine (see the entire press release here).  So, what methods did the researchers use to justify even the modified description?

The operative paragraph in the press release is this one:

“Researchers measured lead levels in soil and drinking water at 200 toxic waste sites in 31 countries then estimated the blood lead levels in 779,989 children who were potentially exposed to lead from these sites in 2010. The blood lead levels ranged from 1.5 to 104 µg/dL, with an average of 21 µg/dL in children ages four years and younger. According to Dr. Chatham-Stephens, first author of the study, these higher blood lead levels could result in an estimated loss of five to eight IQ points per child and an incidence of mild mental retardation in 6 out of every 1,000 children.”

There are many precise numbers implying rigorous research. But, the phrases “estimated the blood levels,” “potentially exposed,” and “could result” should raise a red flag.

The whole thesis of this research is based on guesswork and assumption. The researchers did not measure lead levels in children’s blood; nor did they test IQ levels; and they did not interact with 779,989 children. Further investigation reveals that all the numbers, including the reported blood lead levels, are extrapolations from computer modeling.

The paper title is “The Pediatric Burden of Disease from Lead Exposure at Toxic Waste Sites in Low and Middle Income Countries.” I could not find the full published paper, but I did find the abstract here. From the abstract we find that the numbers reported in the press release are indeed products of computer modeling, not from actual measurement. The paper in question is apparently a subset of a larger study by the same authors:“Burden of disease from toxic waste sites in India, Indonesia, and the Philippines in 2010″ which is available online. The methodology described there confirms that no blood tests were performed. So, all those impressive looking precise numbers in the press release are mere artifacts of the assumptions used in a computer model.

The point here is that while the contention of the research might be correct, the reality is that we don’t know because the researchers, as far as I can tell, never validated the modeling with ground truth. We know no more now than we did before the research was conducted and the relationship postulated.

I think stories like this reflect poor practice in both journalism and science. I also noted that the study was done in conjunction with the Blacksmith Institute, an advocacy group, so there may be some promotional incentive for the press release headline.

The principle danger from this kind of study, besides worrying the public, is that policy makers may read only the headlines and propose inappropriate solutions to problems that may not exist.

A version of this article first appeared in the Arizona Daily Independent.

See also:

Be wary of statistical traps

Public health consultant Steve Milloy, publisher of Junkscience.com and the nonprofit American Tradition Institute Environmental Law Center (ATI) have sued the EPA for conducting illegal life- and health-threatening scientific experiments on human subjects. The tests are still ongoing and conducted “with the assistance of the University of North Carolina School of Medicine” according to Milloy.

Milloy says:

Since at least 2004 and up through the Obama administration, the U.S. Environmental Protection Agency (EPA) has been secretly testing highly toxic/lethal air pollutants on unhealthy human study subjects for the sole purpose of finding out what harm would be caused by the exposures. In no case, were the human study subjects fully informed of the dangers posed by the experimentation, nor were they intended to benefit from the experimentation.

The mere approval and conduct of these experiments (in which the EPA treated human beings as guinea pigs for toxicity testing), not to mention the EPA’s failure to obtain informed consent from the study subjects, violates virtually every regulation established since World War II, including federal regulations and EPA’s own rules, concerning the protection of human subjects used in scientific experimentation. EPA may also incur criminal and civil liabilities from this conduct.

What are the EPA experiments?

EPA has conducted/is conducting at least four separate projects in which already-unhealthy study subjects were/are being exposed to high-levels of diesel exhaust and toxic air pollution particles (known as “PM2.5″). “High-levels” means exposures 10-20 times greater than EPA regulatory standards.

XCON Study. Starting in 2004, the EPA exposed adults with metabolic syndrome (including the elderly) to high levels of toxic PM2.5.

OMEGACON Study. Starting in 2007, the EPA exposed older adults to high levels of diesel exhaust (which contains PM2.5 and other “toxic” substances) and then “treated” them with omega-3 fatty acids to see if whatever harm caused by PM2.5 was mitigated. In 2008, the diesel exhaust was replaced by plain PM2.5.

KINGCON Study. Starting in 2008, the EPA exposed older adults with moderate asthma to PM2.5.

CAPTAIN Study. The EPA is now recruiting older adults (including the elderly up to 75 years) to “… find out if a component of ambient air pollution to which we are all exposed, particulate matter (PM), produced by car and coal-fired power plants, increases the risks of changes in the heart and whether genotype will lessen the risks caused by PM.

　

The findings are given in detail at a new website: http://epahumantesting.com/ . The left sidebar of that site takes you on a guided tour.

A new study from Stony Brook University, published in the journal of Photochemistry and Photobiology, revealed “significant levels of UVC and UVA, which appeared to originate from cracks in the phosphor coatings, present in all CFL bulbs studied.” UVC and UVA can cause skin cancers.

The paper abstract reads:

Compact fluorescent light (CFL) bulbs can provide the same amount of lumens as incandescent light bulbs, using one quarter of the energy. Recently, CFL exposure was found to exacerbate existing skin conditions; however, the effects of CFL exposure on healthy skin tissue have not been thoroughly investigated. In this study, we studied the effects of exposure to CFL illumination on healthy human skin tissue cells (fibroblasts and keratinocytes). Cells exposed to CFLs exhibited a decrease in the proliferation rate, a significant increase in the production of reactive oxygen species, and a decrease in their ability to contract collagen. Measurements of UV emissions from these bulbs found significant levels of UVC and UVA (mercury [Hg] emission lines), which appeared to originate from cracks in the phosphor coatings, present in all bulbs studied. The response of the cells to the CFLs was consistent with damage from UV radiation, which was further enhanced when low dosages of TiO2 nanoparticles (NPs), normally used for UV absorption, were added prior to exposure. No effect on cells, with or without TiO2 NPs, was observed when they were exposed to incandescent light of the same intensity.

See the press release here.

Dr. Miriam Rafailovich, the lead researcher said, “Our study revealed that the response of healthy skin cells to UV emitted from CFL bulbs is consistent with damage from ultraviolet radiation.” She also noted, “Skin cell damage was further enhanced when low dosages of TiO2 (titanium dioxide) nanoparticles were introduced to the skin cells prior to exposure.” Titanium dioxide is frequently used in sun blocker creams and in cosmetics.

Dr. Rafailovich added, “Our research shows that it is best to avoid using them [CFLs] at close distances and that they are safest when placed behind an additional glass cover.”

Reader note: I did not have access to the full paper, so I am unable to assess their methodology.

See also:

How Many Haz-Mat Suits Do You Need to Change a Lightbulb?

The EPA procedures you must follow if you break a compact fluorescent light bulb

Would you pay $50 for a light bulb?