Health & Environmental Research Online (HERO) is the site online to find the research that the EPA has been doing. Yesterday’s blog described the Particulate Matter Study using diesel fumes blown directly into the lungs of asthma and other chronic breathing issues. Today, I’m going to cover the other studies done under the HERO umbrella.
Ammonia (Draft, 2012)
DCM (Dichloromethane) (Final, 2011)
1,4-Dioxane – Inhalation (Draft, 2011)
Hexachloroethane (HCE) (Final, 2011)
Libby Amphibole Asbestos (Draft, 2011)
Methanol (Non-Cancer) (Draft, 2011) (67-56-1)
Tetrachloroethylene (Perc) (Final, 2012)
Trichloroacetic acid (TCA) (Final, 2011)
Trichloroethylene (TCE) (Final, 2011)
Vanadium Pentoxide (Draft, 2011)
Following the links, we find the page that explains what the EPA thinks it’s doing. Perhaps more frightening is a section at the bottom of this page:
Does EPA evaluate whether children may be at greater health risks than adults?
Almost 500 years ago Paracelsus (1493-1541) wrote: “Dosis facit venenum” or “the dose makes the poison.” The relationship between dose and response (health effect) is still one of the most fundamental concepts of toxicology – or is it? For pollutants that act as developmental toxicants, the same dose that may pose little or no risk to an adult can cause drastic effects in a developing fetus or a child. Methyl mercury is but one example of a chemical that is much more toxic early in life. Scientists have become increasingly aware that children may be more vulnerable to environmental exposures than adults because:
their bodily systems are developing;
they eat more, drink more, and breathe more in proportion to their body size; and
their behavior, such as crawling and hand-to-mouth activity, can expose them more to chemicals and microorganisms.
In light of what is now known about the greater susceptibility early in life to some stressors, Executive Order 13045 — Protection of Children from Environmental Health Risks and Safety Risks — was issued in 1997. This Executive Order directs that all federal agencies, including EPA, shall make it a high priority to identify and assess environmental health risks and safety risks that may disproportionately affect children; and shall ensure that their policies, programs, activities, and standards address disproportionate risks to children that result from environmental health risks or safety risks.
Note: To assist scientists in assessing risks specifically to children, EPA has developed A Framework for Assessing Health Risk of Environmental Exposures to Children along with specific guidance to risk assessors including Guidance on Selecting Age Groups for Monitoring and Assessing Child-Hood Exposures to Environmental Contaminants and Supplemental Guidance for Assessing Susceptibility from Early-Life Exposure to Carcinogens.
There is a course for determining the ethical status of human experiments. It is called Program in Human Research Ethics (PHRE). So there are actually regulations to be considered. Let’s see what some of them are:
In the context of research, vulnerable individuals are defined as those who cannot fully protect their own interests.
Examples of vulnerable populations include:
Mentally impaired persons
Other individuals who cannot fully protect their own interests
Subparts B, C, and D of EPA’s human studies rule provide additional protections for three specific vulnerable groups:
The key part of the exposure research definition is that the exposure would not have occurred but for participation in the study.
In intentional exposure research, the researcher controls some aspect of the exposure under study.
One way to do this is by intentional dosing where the study substance is administered directly.
Another way is by controlling the subject’s behavior to bring him or her into contact with a study substance already in the environment.
Risk level (including zero or minimal risk) is irrelevant to the determination of whether the research involves intentional exposure or is observational.
A direct dosing study: Asthmatics and non-asthmatics are exposed, in a chamber, to varying levels of air containing particulate matter in order to determine the effects on their breathing.
A controlled exposure study without direct dosing: Participants are asked to walk, according to a scripted protocol, on a deck treated with commercially available wood preservative. Exposure to the chemicals is measured by wipe samples collected from the bottom of their shoes.
Subpart B of the regulations prohibits intentional exposure research, under all circumstances, in children and women who are pregnant or nursing.
The ban is categorical and is not based on a risk-benefit ratio, including prospect of direct benefit.
So we find that by their own rules, the EPA is not allowed to do “intentional exposure research” on children and women who are pregnant and nursing. That’s reassuring.
I understand how difficult it is to do research around this ban. But a well designed project can work around it. An example is a Spanish study on the association between air pollution and birth weights published in 2009. And the whole list of others referred to in the bibliography.
Let’s hope the EPA meant it.