Laws
At least theoretically, scientific facts are supposed to be
universal. Therefore, the EPA cannot
have a law of gravity that is different than the one used by the FDA. On the other hand, regulatory policies
enacted under different statutes may vary not only between agencies, but within
the same agency. For example, the National Park Service can
have different speed limits in national parks than the Department of
Transportation does on interstate freeways.
No one thinks that violates any laws of nature.
When an ought-to-is argument is used to create a lab-cloaked
pseudoscientific fact, the public will expect it to be valid throughout the
Federal Government. That’s what the
shell game is all about. If you can
confer the aura of science onto a social policy, then when other agencies with different regulatory statutes get in the way, you can call it political interference with the science. Well, at least that’s what the true believers
think. But, unbelievers think otherwise.
The Reference Dose for Lead
The EPA doesn’t have one.
Many years ago, the agency (EPA,
2004) decided it wouldn’t be a good idea:
By comparison
to most other environmental toxicants, the degree of uncertainty about the
health effects of lead is quite low. It appears that some of these effects,
particularly changes in the levels of certain blood enzymes and in aspects of
children's neurobehavioral development, may occur at blood lead levels so low
as to be essentially without a threshold. The Agency's RfD Work Group discussed
inorganic lead (and lead compounds) at two meetings (07/08/1985 and 07/22/1985)
and considered it inappropriate to develop an RfD for inorganic lead.
Although the lack of a threshold was the primary
justification for not having an RfD, another possible motivation is that it
allowed, and even demanded, that different program offices develop their own
strategies for dealing with lead. Specifically,
the use of lead paint was banned, while levels for lead in both air and water
were justified with a cost-benefit analysis.
The FDA also developed their own standard for limiting exposure to lead
from food (Carrington, and Bolger, 1992).
The Reference Dose for Methylmercury
Most reference doses are developed by the Office of Research
and Development for use by multiple offices.
However, the Office of Pesticide Programs develops many RfDs their own
with some minor procedural differences from ORD. The reference dose for methylmercury is unusual. First, even though the Office
of Air also regulates atmospheric mercury that may be transformed in to
methylmercury in the environment, it was developed by the EPA Office of Water
for their own use. Second, instead of
being used to develop regulations, the RfD is primarily used to develop fish
consumption advice for recreationally-caught fish.
In 1999, congress asked the National Academy of Sciences to evaluate
the USEPA Reference Dose for methylmercury.
That wasn’t a good idea; if you ask a political question, you are bound
to get a political answer. So, arguably
the main damage was done before the committee ever met. But, the main body of the NRC report pretty
much stuck to the science. They
calculated a benchmark dose, which does have a factual interpretation, and the
then they applied a standard safety factor of 10 to get a Reference Dose, which
doesn’t. However, in the executive
summary, the following statement appeared:
The committee estimates that over 60,000 children are born each year at risk for adverse neurodevelopmental effects due to in utero exposure to MeHg.
The FDA took interest in this statement and sent an inquiry
to the chairman of the committee asking what, exactly, were the developmental
effects that occur in 60,000 children each year? This prompted the following response (Goyer,
2000):
The term “at risk” refers to children born each year from mothers with a level of methylmercury that is above the current RfD. (Note that the subcommittee concluded that the level of EPA’s RfD is scientifically justifiable.) The offspring of those mothers are exposed to mercury levels that are not considered safe, and, therefore, the committee considered them to be “at risk”. The calculation presents an estimate of the number of children at risk because of high exposure (maternal dose exceeding current RfD). That number should not be interpreted as an estimate of the annual number of adverse neuro-developmental effects. The committee does not believe it is possible to estimate a meaningful number of children that might be affected within the at risk population. It should be noted that there is presently no established NOAEL (no observed adverse effect level of methyl mercury). Therefore, there may be some increased risk above population background levels to developing infants below the 95 percentile. These infants are not included in the 60,000.
That, my friends, is the shell game spoken from the bully
pulpit of the National Academy of Science with all the sound and fury of
protection, yet signifying nothing about what the risk really is. Is-To-Ought-To-Is-To the FDA, where agency
management fell for it hook,
line, and sinker. That the lawyers
were so gullible is somewhat understandable.
They thought of the National Academy as the supreme court of
Science. Telling them that a) the RfD is
not a statement of scientific fact, and b) there is no supreme court of science (Carrington, 2008) just didn’t register. After all,
congress asked for the RfD to be evaluated as a scientific fact, and therefore,
that must be what it is. You might think
the FDA doctors would know better, but most doctors are not scientists either;
at least that’s the only way I can explain it.
In any case, that’s when the war started.
References
Carrington CD and Bolger PM (1992). An assessment of the hazards of lead in
food. Regul Pharmacol Toxicol 16:265-272.
Carrington PD (2008). Freedom to Err: The Idea of Natural Selection in Politics, Schools, and Courts. William & Mary Bill of Rights Journal 17:1-42.
Carrington PD (2008). Freedom to Err: The Idea of Natural Selection in Politics, Schools, and Courts. William & Mary Bill of Rights Journal 17:1-42.
Goyer, RA. Chair,
Committee on the Toxicological Effects of Mercury. (2000, December 1). Letter to
Joseph A. Levitt.
National Research Council (2000). Toxicological
Effects of Methylmercury. National
Academy Press, Washington, DC.
U.S. Environmental Protection Agency (2004). Lead and compounds (inorganic) (CASRN
7439-92-1). http://www.epa.gov/iris/subst/0277.htm
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