9. Risk and Law: Pesticide Paradigm
19
September

By Adem Lewis / in , , , , , , , , , , , /


Prof: Today I want to
talk about the relationship between risk and law.
And I want to do this in the
context of the history of agriculture and regulating
pesticides during the twentieth century.
And also I want to have you
consider the idea of risk. And I’m reminded as I think
about this of T.S. Eliot’s line,
“Only those who will risk going too far can possibly find
out how far one can go.” So many believe that
environmentalists are in the business of trying to absolutely
minimize risk as opposed to balance the threat of loss or
danger against other opportunities.
And others argue that without
risk in life, things would be pretty boring.
I was traveling through Europe
last summer on a lecture tour, and I saw this village sitting
on the top of a cliff. And I wondered to myself about
the village, and I wondered how they chose to build so close to
the edge, and what kind of thinking was in their minds.
And I could imagine that this
used to be a number of fields where they grazed cattle and
sheep, and they probably worried about
losing cattle and sheep across the cliff.
Then as it grew into a little
village, I can imagine them worried about their children
playing near the edge. So much of environmental law is
about thinking about the buffer zone or the safety factor that
you would want to use to offer sufficient protection against
significant damage. So the idea of risk and
understanding risk is really a fundamental aspect of human
logic and instinct. Within law, it tends to become
defined as probability of loss, probability of damage.
It might be an endangered
species, it might be air quality, it could be human
health. And it’s often expressed in
both quantitative and qualitative terms.
So particularly over the past
thirty years, the field of quantitative risk
assessment has grown in importance to try to understand
what happens to chemicals or to species,
what kinds of pathways they travel,
what kinds of problems might occur from chemical release and
chemical movement. And increasingly,
it’s more sophisticated mathematically,
and more difficult to understand the different sources
of uncertainty that are embedded in these estimates of risk.
You may have heard of the idea
of an acceptable risk level for cancer or some other undesirable
outcome as being one in a million.
Well, the government has used
that standard on many occasions: a “one-in-a-million excess
risk.” Well, to put that into
perspective, you might think about the H1N1 infection.
So what was the actual
morbidity rate over the past year for H1N1?
Well, it turns out that you
would first think about the number of people in the United
States, say roughly 300 million people.
And you’d want to know what the
incidence rate was in the illness.
And those now,
I was looking at them last night on the Centers for Disease
Control and Prevention website. Their estimate is that between
30 and 45 or 50 million people carried the virus and had some
adverse effect from it. And then I was looking at the
statistics for mortality. And between 15 and 20,000
people were killed by the illness.
Why the uncertainty associated
with the estimate? Well, it’s an illness that can
harvest, so to speak, in epidemiological terms,
the more susceptible, those that have serious
background illnesses. So the expression of risk for
morbidity, which means illness,
would be roughly let’s say 30 million out of 300 million,
which is really quite striking. There are few illnesses that
have that rate. So roughly a one-in-ten risk.
And I mentioned when I started
this brief aside that a one-in-a-million risk is often
thought of as acceptable. The distinction between
environmental risks that are not biologically based or generated
by pathogens like H1N1 and chemical risks is often that
there was a clear causal relationship between exposure
and an understanding of the source of the illness,
and also what might be done to manage it more effectively,
such as the vaccine. By the way, the vaccine that
was produced and distributed this year was really pretty
remarkable. It was extremely effective,
and the incidence rate was projected to be far higher than
it actually turned out. So this concern over
quantitative risk assessment, try and understand who’s most
vulnerable, who’s going to basically
sustain the most serious effects,
this preoccupies the Environmental Protection Agency,
the Food and Drug Administration when they’re
thinking about allowing a new drug to be added to the
marketplace. And really, the decision is all
about balancing, trying to think through what
the quality of the evidence is and should the dangers be
balanced against the benefits. And this standard for balancing
has shifted dramatically over the twentieth century.
So that the lecture today
really will trace the evolution of law and demonstrate how it’s
shifted from 1906 to the present.
And I want you to think about
how it really reflects changing science as well as changing
human values. So that as the science gets
stronger, we understand the relationship
between an exposure and an adverse outcome and oftentimes,
the government will intervene by setting a new law or a new
regulation. So that back in 1906,
the Pure Food and Drug Act of 1906 was passed after Upton
Sinclair published The Jungle,
that described filthy slaughtering conditions in
Chicago. The Pure Food and Drug Act was
passed in 1906 as well, and it forbade foreign and
interstate commerce and adulterated or fraudulently
labeled food and drugs. So products could now be seized
and condemned, and offending persons could be
fined or jailed, and fresh, canned,
or frozen food shipped in interstate commerce must be pure
and wholesome. That was the new standard back
in 1906. So basically,
the idea of adulteration and the idea of fraudulent labeling
became important. So the very first attempts to
try to control risk in society related to food and agriculture
really concentrated on the idea of labeling,
the idea of making sure that the product inside the package
was what it claimed to be and that it had an effectiveness
that was also claimed, and that it wasn’t excessively
dangerous. They really worried about
farmers buying pesticides, disposing pesticides,
and then basically having the container filled with sugar or
flour. How would they know the
difference? There were many cases of
fraudulent manufacturing practices early in the twentieth
century, before this law was put into place.
Another critical statute that
built on this was the Insecticide Act of 1910 that
similarly prohibited fraudulently labeled pesticides
and set standards for purity. So the idea of ingredient
labeling was added to the Insecticide Act.
And it was designed to protect
farmers from dangerous and impotent pesticides.
If you jump forward,
you find that the Federal Food, Drug, and Cosmetic Act of 1938
is important. And it became the home for
pesticide regulation for many years until EPA took over that
responsibility in 1970. And the Food and Drug
Administration was authorized to set, in 1938,
limits for chemicals in food. So the recognition that if you
sprayed a field of corn and you harvested the corn and then you
sold it in the supermarket that it might still carry residues,
this was beginning to be well recognized back in the 1930s.
The criteria used to set the
tolerances was really quite interesting at that time.
It wasn’t a health-based
criterion. It wasn’t an
environmentally-based criterion. It was how much residue should
be allowed to remain on the food product if the chemical is
sprayed in the field at a dose that’s effective to get the job
done, in other words,
to kill the pest? So that’s kind of interesting.
So it was really a standard
that was set to make sure that the residues would not cause the
food to be pulled out of the marketplace because they were
adulterated. So they were really designed to
protect the farmer and the economic value of the crop,
rather than the health of the population or the environmental
quality. The Miller Amendment of 1954
required tolerances for all pesticides if they might remain
as food residues. And then the Delaney Amendment
in 1958 became infamous, because it set a zero risk
standard, a tolerance for carcinogens in food.
So the exact language is that
if a pesticide or other food additive is carcinogenic in
laboratory animals or in humans, and that was the first time in
law that using evidence from laboratory animals was
considered to be sufficient in order to ban the use of a
chemical. Then it could not be used in a
way that would cause the residue to be present in the food
supply. Now, you can imagine that these
chemicals were applied to many different crops.
And I mentioned to you that DDT
in my last lecture was applied so heavily to so many different
foods, 300 different food crops had
tolerances by the mid-1950s. But the government’s ability to
detect these chemicals is really important to this story.
So if you use insensitive
detection technology, in other words,
supposing that your chemical detection equipment is only
capable of finding residues at the part per 100,000 level,
ten to the minus fifth, or even part per million level.
And the chemical is there,
but it’s there at the high part per billion level,
the chemical test is going to come back negative,
it’s going to come back as a non-detect.
So gradually,
you see this very interesting evolution in the concept of
purity and what constitutes a safe and pure environment that’s
very much driven by the sensitivity of the detection
equipment. So during the century as the
detection equipment became more and more sensitive.
Now for some dioxins,
we can detect those down to the part per quadrillion level.
And many chemicals are present
in food at the part per trillion level.
It’s got people thinking about
well, what does that mean? What does that mean to their
potential to influence human health?
So back in the ’40s and ’50s,
the detection technology was really quite limited,
and also the sampling was quite limited,
so that they really weren’t sampling that many foods.
You can imagine the scale of
the problem this presents today, given the international
character of our food supply. I ask this question with
respect to several commodities, first I started with apples and
wondered how many times the government tested apples for
pesticides. And then I looked at bananas.
And for bananas,
for a chemical that was, when I looked about eight years
ago, one of the most heavily used
insecticides on bananas grown in the tropics,
the government was looking at about fifteen to eighteen
samples of bananas for this compound when I then was able to
calculate that several trillion individual bananas had been
imported into the nation during that year.
So one needs to think about
what standards are in place in different parts of the world,
where that food is likely to go, keeping records of import
statistics, and then think about what kind
of a sampling design would be necessary in order to find these
residues in a way that might eventually lead to health
protection. So the Delaney Amendment was
really quite striking. It was adopted really with
great support in Congress, in part because of the U.S.
fascination with cancer and
also cancer management. So this grew in part because of
the nuclear weapons testing era, but it is curious that within
the European nations, the regulatory approach to
environmental quality has not been as concerned with cancer,
it’s been more concerned with neurological decline and also
reproductive health. So it raises really interesting
questions about why the preoccupation in the United
States with cancer. So the first seriously health
protective statute that we can find in environmental law has to
do with food and it has to do with pesticides,
and it’s contained in this Delaney Amendment.
By the way, this amendment
applies to all food additives. And a food additive could be
defined also as a coloring agent, like the salmon coloring
I spoke of. It could be defined as a
packaging material migrant. It could be a flavoring agent
as well, so that the standard is very clear.
If it induces cancer in animals
or in humans, then it is not allowed.
Curiously, there is a clause
within the statute that applies only to pesticides that are
defined as food additives if they concentrate.
And you remember the story I
told you the other day about taking a grape and extracting
all the water out of it, or taking corn and extracting
the oil out of it, and having to be thoughtful
about what that really might mean for chemical residues.
So if you are concerned about
oil extraction, you need to think about
lipophilicity. So if you’ve got a chemical
such as a chlorinated carbon that is likely to bind onto fats
of one form or another, extracting the oil out will
likely also concentrate the chemical residue.
So if you look in the code of
federal regulations, it’s very curious.
You can go over to the law
library and pull out the code of federal regulations on
pesticides. Actually, it would be a good
assignment for teaching fellows to disseminate.
Go look at the code of federal
regulations for pesticide residues in food,
and you’ll see 40 CFR, 135.
And you go to the appendix,
and the appendix is several hundred pages long of individual
pesticide-food combinations. So I was quite struck by his
several years ago. And I added all of these up and
it turns out that there are about 10,000 different
pesticide-food combinations. And if you look carefully at
these combinations that set limits for benomyl in bananas or
let’s say chlorpyriphos in apples or DDT in milk,
that standard is still in place by the way.
It’s kind of interesting,
even though DDT was banned, as I said the other day,
in the 1970s. But if you look carefully,
you’ll see that you get a different residue limit allowed
for fresh corn or fresh apples or fresh soybeans than you do
for the processed product. And it’s basically because of
this concentration factor. So water extraction,
making raisins out of grapes, making wine out of grapes,
or making oils out of different kinds of grains can have this
effect. The Federal Insecticide,
Fungicide, and Rodenticide Act of 1947 was the central statute
that was passed, and it really set the stage for
the U.S. Department of Agriculture’s
authority to issues licenses or registrations.
So as I mentioned earlier,
the idea of registering a pesticide or allowing it to be
used for a certain crop, these registrations were given
out one after another after another,
decade after decade, so that by 1960,
there were 50,000 different pesticide registrations that had
been issued. And by 1970,
there were nearly 70,000 pesticide registrations.
And a registration is given for
a specific chemical use, and it may be also assigned for
a specific package. So you may have chemical X,
and that has one registration. And then it may be sold also
with chemical Y or chemical Y and Z, and they would have
different registrations assigned them.
And they might have different
registrations assigned for different kinds of uses,
so that these chemicals were not just used on food
commodities. Where else might they be used?
Well, think about it.
Many of the buildings at Yale
are sprayed by pesticides indoors.
So that type of use often had
to have a separate registration. Sprayed in subways,
sprayed in vehicles, added to materials such as
plastics that are components of cars or that are components of
urethanes, for example,
that coat the wood here. So that plastics have carried
biocides into our environment in a whole set of ways.
And the government had to keep
track of where these chemicals were going, and had to license
each of these distinctive uses. So the FIFRA of 1947 was
important because it defined these chemicals as economic
poisons, implying yes,
they’re poisonous, but they also carry an economic
benefit so that we need to look at this using a utilitarian
balancing standard, so that risk-benefit balancing
became the phrase that guided U.S.
Department of Agriculture to
crank out these registrations. It also extended the
regulations, not just to insecticides,
but to herbicides and rodenticides.
And right now,
in terms of volume of chemical released in the world,
you find the herbicides are the most heavily type of pesticide.
So there are pesticides,
there are insecticides, herbicides, rodenticides
designed to kill rats or mice, slimicides, that are applied to
kill slime and algae on the side of nuclear power plant cooling
towers. There are nearly a hundred
different chemicals. Any swimmers in the room?
Probably a few,
or former swimmers? Well, there are nearly a
hundred different pesticides that have been registered for
use in swimming pools to kill a variety of viruses,
bacteria, as well as molds and other pathogens.
If you think about that
carefully and you think about the relative risk that is
associated with using those chemicals as opposed to not
using them, it’s probably a really good
choice, given the illnesses that could
live in that environment. So that this statute was the
first to really break down these different categories of biocides
and really assign different regulatory responsibility.
No authority was given to the
Department of Agriculture, however, to remove hazardous
chemicals from the marketplace. So that they always found that
the benefits outweighed the risk.
There are no instances that I
can point to that the Department of Agriculture either banned a
chemical or found that the risk was too serious.
They may have adjusted the
allowable use rates or the type of environment it could be
released to or the type of crop. But no product bans.
And think about this.
The government gave,
the Congress gave the Department of Agriculture the
authority to manage this program, to implement the
program. Now, is that a good idea?
What’s the Department of
Agriculture’s basic role? Well, it’s really to promote
economic production of a variety of different agricultural
commodities. And they really also do not
have and have not had much expertise in environmental
science to know what happened to the chemicals once they were
released or to think carefully about the health effects.
So the medical expertise within
the Department of Agriculture throughout their period of
jurisdiction, which ended in 1970,
when the Environmental Protection Agency was formed,
was a period when they really had very little expertise in
environmental science or in medical science,
which is really fundamental to the way that we’re thinking
about regulating pesticides today.
The FIFRA amendments in 1964
came after Rachel Carson’s book, Silent Spring,
raised the alarm and caused the population to be quite upset
about pesticide residues, particularly their effect on
wildlife, but also growing recognition
that these chemicals could build in the human body.
And also the Food and Drug
Administration’s admission that they had found pesticides in
human breast milk as early as 1952.
The public wasn’t warned about
this. And basically,
if you find a chemical, regardless of what it is,
you find it in another species of mammal’s breast milk,
you can presume that it’s likely to get into human breast
milk as well. So Rachel Carson’s Silent
Spring turned out to be a real watershed,
not just legally for pesticides, because it really
increased the sense of susceptibility to biocides or
the economic poisons, but it really met with quite a
bit of resistance in Congress. Again, this was the end of the
nuclear weapons testing era in the atmosphere.
And it was also a period of
great unrest in the United States.
The origin of the Civil Rights
Movement may be traced to this period.
The Civil Rights Act of 1964,
recall that. Also, we were getting more
deeply embedded in the war in Vietnam at that point in time.
And environmentalism was
growing up, creeping up on the agenda.
But it was really quite an
interesting period. Congress, however,
was preoccupied. Other than making some minor
revisions to the statute that included adding these words:
caution, warning, and hazard,
depending upon the relative toxicity.
This didn’t really help very
much because of public confusion about what those phrases meant.
And the Department of
Agriculture’s secretary was given authority finally to
remove pesticides from the market based upon a finding of
imminent hazard to public. Now, EPA was created in 1970,
and it was given the responsibility to manage
pesticides and it was consolidated from other
agencies. Some fifteen or sixteen
different subunits of different agencies were pulled together to
create EPA back in 1970, including the Department of
Agriculture, that had formerly had the
pesticide management responsibility.
So you can imagine entire
sub-bureaucracies picking up and moving their materials to EPA.
And the stories from some of
the early administrators about how they did this and what the
effect was are really quite striking.
They described that the
Department of Agriculture had kept files on individual
chemicals, but they were completely
disorganized, often just handwritten,
often with no environmental science data,
often no testing of chemical presence in different
commodities that it had been licensed to be used on.
And some chemicals had no data
at all. So EPA was in this situation of
becoming immediately responsible for 70,000 different pesticide
registrations. The public was quite concerned
about these residues getting into their bodies and into the
environment and the wildlife effects.
So they felt a lot of heat.
Increasingly,
environmental laws had these citizen suit provisions,
so EPA was getting sued in the early 1970s,
and they got sued on a variety of compounds,
such as DDT and aldrin and dieldrin.
And they were forced to go back
and look at the data that they had available,
and they found that they really had very little data to justify
many of these registrations. But the law was set up that
forced them to look at this problem a chemical at a time.
So if you’ve got 70,000
different chemicals, and the law requires that you
look at them one at a time and you’ve got a staff that doesn’t
have the basic data in place, this basically put the
regulatory process in deep freeze.
So how would you manage that if
you were responsible? Well, Congress thought about
this, and they allocated more and more money to the
Environmental Protection Agency. And EPA became much more
aggressive and starting banning chemicals.
They banned DDT first and then
aldrin and then dieldrin, heptachlor and then chlordane.
All of these were the
chlorinated hydrocarbons. The FIFRA amendments of 1975
gave the Secretary of Agriculture authority to be
notified of pending cancellations,
which meant that he was given a voice to oppose cancellations.
But the Environmental
Protection Agency really became the stewards for human health
and environmental quality so that the Secretary of
Agriculture’s voice was diminishing in the 1970s.
Congress also recognized that
EPA’s not making much progress on this sea of chemicals,
so they’d better do something about it.
They mandated that each
chemical had to be reviewed within a nine-year deadline.
Well, EPA was not able to
accomplish that, so the ’70s and the ’80s and
’90s were all great examples of what I call the rule of twenty,
that each chemical might get some attention every twenty
years. But what does that mean?
You can think about the fact
that new chemicals are being added to the marketplace,
new registrations are being issued,
the data are lousy and EPA is taking twenty years to review a
single chemical, that doesn’t make sense.
The science is evolving at a
lightening pace on where the chemicals are in the environment
or what the health effects are, or what the effects on
different species are. And EPA is like this ship that
is frozen, it’s icebound, unable to move with a speed
that it really needed to. Well, this was recognized by
the National Academy of Sciences,
in two publications that I had a chance to work on,
one regulating pesticides and food that really critiqued the
Delaney paradox. And a bunch of us thought that
the zero risk standard as it had been interpreted by the Food and
Drug Administration really did not make much sense.
FDA had interpreted zero risk
to mean a little bit of risk. So de minimis is the
phrase that it used. And de minimis means a
trivial amount of risk. And they define that generally
as a one-in-a-million risk threshold.
So that this was a curious
experience for me, because it was my first
exploration of the human diet and its variability.
So I started poring through
food intake surveys, which is the reason that I
asked a section on Monday night to keep track of just one day of
your own diet. Think about that,
what foods do you eat, as a way of thinking about how
patterns in your diet might lead to predictable patterns of your
exposure to residues that had been allowed by government.
So in this case,
we were looking only at that subset of chemicals that had
some evidence of carcinogenicity.
So that these chemicals induced
cancer in animals or were known to induce cancer in humans.
And we were thinking
particularly about how cancer risk might add up across the
chemicals. So a hundred different
chemicals that are cancer inducing in laboratory
experiments, how would you deal with that issue of risk
additivity? Would it be possible that there
may be a negative effect on risk if you had two chemical
exposures at the same time? Well, scientists have found
some cases where that actually occurred,
where a lower risk chemical is able to bind onto a site in a
cell and prevent a higher risk chemical from doing the same
thing. In other cases,
there’s a synergistic relationship,
so that the risk is not just additive,
but if you’re exposed to chemical A and then chemical B,
you’ve got a higher risk of getting cancer.
So working with a bunch of
specialists in cancer, as well as specialists in
residue chemistry and exposure analysis,
we came up with a not too complimentary picture of the way
that EPA had regulated carcinogens in the food and
recommended also that they pay much more attention to the
individual diet, that the diet was likely to be
the key route of exposure to a variety of different chemicals.
The second book flowed from the
first by the National Academy of Sciences, called Pesticides
in the Diets of Infants and Children.
And this focused on a finding
inside the red book, the finding that there’s a lot
of variability out there in the diets that people eat that is
quite predictable. So if you’re Italian,
you’re likely to eat more tomato products.
If you’re Latino,
you’re likely to eat more corn products.
If you are an African American
from the southern part of the United States,
people generally eat more greens.
If you are living in
California, you’re going to eat more fresh produce than you
would if you live in the Northeast.
Its cost does not go up the way
that it does in the Northeast. So diet varied by season,
it varied by region of the country, it varies by age,
and it also varies quite a bit by ethnicity.
So if you don’t understand
these differences in dietary patterns,
you really don’t have much hope of understanding the variability
in the chemical matrix that these individual diets might
convey into your body. So it also presents a really
kind of an interesting idea that you could use cropping patterns
as a way of predicting which chemicals make their way into
certain environments. So if you were looking at the
effect of corn on environmental quality in the United States,
corn production, you would want to know where it
is planted. Predominantly in the Midwestern
part of the U.S., ground zero is pretty much Iowa
through Ohio and Pennsylvania. And if you map out the pattern
of chemical use, you’ll see that herbicides are
applied much more intensely in this area than in other parts of
the nation. And that explains why herbicide
residues are detectable in the water supplies of nearly 30
million people in the United States and also in human
tissues. So that this understanding of
dietary diversity turned out to be extremely important because
it had been completely neglected by environmental law.
And the diversity in patterns
of exposure in environmental law is something that I became
curious about and wondered about whether or not you’d find the
same thing relative to drinking water.
Would you find the same issue
relative to air quality? Are there pockets of high
exposure out there in the population that could be
predictable that would make environmental law and regulation
able to focus in a way that was more effective?
And the answer is yes.
So as we look across cases over
the next couple of weeks, we’ll see the same pattern
emerging, that once you understand
variability in the diet, in other words,
once you focus in and you look for pockets of high exposure,
high consumption of corn or high consumption of a certain
cluster of foods. Or you look at certain
populations, such as athletes,
that have a higher respiration rate than non-athletes do,
that because of that higher respiration rate,
they’re going to absorb more chemicals that are present in
the air. So across a whole array of
different kinds of environmental problems that are managed by
law, there’s basically,
there had been neglect of this issue of variability.
So how do you take a body of
law such as the body that I just described to you for these
chemicals, and transform it to be more
sensitive to the reality of these patterns of chemical use
and exposure? So what I’m painting here is a
picture of what I think of as fractured science and fractured
law, so that the legal authority for
pesticides is now broken into three different bureaus,
the Environmental Protection Agency,
that is responsible for tolerance setting,
but also toxicity testing. The Food and Drug
Administration is responsible for detecting residues in the
food supply. And the Department of
Agriculture is responsible for the enforcement of these
statutes in meat and poultry, and also for the assessment of
economic benefits associated with producing the nation’s food
supply. So you’ve got these different
agencies with different legal mandates, and they tend not to
talk to one another. So that in Great Britain,
they’ve created a new food safety organization that is
really quite distinctive as a model.
They had the same fractured
pattern of bureaucratic control in Great Britain,
and they decided that they would consolidate that.
They’d centralize the authority
in one group. And it’s very curious,
because by doing that, it has allowed conservative
administrations to slow down regulation and to become less
environmentally protected much more quickly than if the
authority is diffused among different agencies.
So this is a very interesting
kind of a problem. The primary authority for
tolerance setting was taken away from the Department of
Agriculture, just like the authority for
regulating nuclear power was taken away from the Atomic
Energy Commission, so the Nuclear Regulatory
Commission was created. So you don’t want the producer
and the protector of the public interest to be sitting inside
the same organization, that’s really the key
principle. For those of you that I haven’t
stunned to death enough with this lecture so far,
if you want to know more about pesticide science and history in
law, I published this book about ten
years ago, and this really details the
description of how we discovered that kids were more exposed to
many different pesticides than adults,
that was eventually adopted into the Food Quality Protection
Act, passed in 1996.
So that this law was designed
to deal with this problem of risk being not equally
distributed in society. And it included a new general
safety standard. It did away with the
risk-benefit balancing standard and it said,
“Okay, instead, EPA must make its choices based
upon the phrase ‘reasonable certainty of no harm.'”
It’s kind of interesting. If you were given the
assignment to include a decision standard in a statute that was
health protective, what would you choose?
Would you choose a balancing
standard? Probably not.
Would you choose the Delaney
clause model, which is a zero-risk standard?
You might.
Would you choose a standard
such as this, reasonable certainty of no
harm? Well, you can imagine that this
was hammered out politically in Congress with great interest on
the part of chemical companies and also food manufacturers to
try to understand what its implications might be for them.
It also requires a finding of
safety. This had not been part of the
law until 1996. So EPA must now find that
chemicals are safe for children. This is really quite new and
striking. And it requires a tenfold
additional safety factor to account for uncertainty in the
data that they have as they set their limits.
So that this idea of a buffer
zone, if you think the risk is X, then you have to allow X over
what in order to set your standard for exposure?
Well, do you want a tenfold
safety factor? Do you want a hundredfold,
a thousand fold? Well, the tradition had been to
use a hundredfold safety factor. So if you think that this is
what it is, you account for your absence of knowledge or your
ignorance, by dividing the allowable level by a hundred.
And in this case,
Congress said, “That’s not good enough.
You a have to divide it by an
additional ten to account for the uncertainty about the
distributional patterns.” And also, the issue of some
groups being more susceptible to these chemicals than others.
It also required that the
agency for the first time needed to consider how people might be
exposed to the same chemical, not just from food or different
crops, but food, drinking water,
and other kinds of environments.
So the same chemical might be
sprayed on fruits and vegetables, and it might get
into dairy cattle. But it also might be sprayed in
your apartment building. Or it also might be used as an
algaecide in a swimming pool. So that formerly EPA had just
kind of given out licenses as USDA had to these different
allowable uses, and not thought about the fact
that to somebody as they basically walked through their
daily life could be exposed to the same chemical across these
environmental compartments, so to speak.
So the idea of aggregate risk
is new, and it’s an attempt to think
about the complexity of the way that these compounds can move
through environments. The idea of cumulative risk is
also new. That the government had to
consider the idea that a group of chemicals might act the same
way in the human body, and the risk might be at least
additive, if not synergistic.
So for the first time in 1996,
EPA had to review all of its tolerances to think about
cumulative risk. And the pace of review was also
sped up so that all chemicals that it had licensed had to be
reviewed by 2006. That was accomplished,
quite remarkably. But the critique I could give
you of the quality of the review is a different matter.
And finally,
Congress directed the agency not to give equal attention to
every pesticide, but to come through,
or to develop some sort of a strategy to concentrate and
focus on chemicals that it thought would be the most risky.
So how would you do that?
How would you define the most
risky chemicals? Well, you’d try to find those
that had the highest dose-response rate.
In other words,
they seemed like they were the most potent, or the most toxic.
But you’d also probably want to
concentrate on chemicals that were persistent,
chemicals that got into different environmental
compartments, or chemicals that were used in
food or environments that people frequent,
foods that people eat a lot of or environments that were highly
frequented, such as schools or such as
occupational settings or homes. So that the idea of strategic
attention on the most toxic chemicals is an important
concept. So what’s happened here as you
think back across history? You’ve got kind of a sequence
of changing regulatory priorities.
And you might ask yourself,
well, why is that? So that the first attempt back
in 1906 was to protect the economy of farmers against
fraudulent labeling. Then the obligation became to
protect food and crop uses. So set limits for levels of
residue in different kinds of foods.
Then wildlife residues became
extremely important as people worried about how chemicals were
causing decline in species that were really much loved in the
United States, particularly large raptors,
bald eagles, the national symbol,
or the gold eagle, the peregrine falcon,
ospreys that now you can see coming back along the shoreline
here in Connecticut, if you take the train from New
Haven up to Boston, for example,
and look out over the salt marshes,
you’ll see these poles sitting in the middle of salt marshes
with ospreys. Ospreys came very close to
extinction because of the chemical DDT that was building
up in its body and causing its eggshells to thin so its
reproductive success declined. Soil contamination became
important as instances where a chemical had been used in the
field one year and had persisted in that field.
Another tenant farmer comes
along the next year and plants a different crop.
That crop is not permitted to
have that chemical used on it, but it absorbed the chemical up
through its roots and becomes adulterated.
So that failure to think about
soil contamination was causing some foods to become adulterated
in ways that were not predictable.
And drinking water
contamination has come late to the attention of the
Environmental Protection Agency. Why would that be?
You know, if you think about
water as one of the most consumed foods in the human
diet, why wouldn’t the government
have paid more attention to water?
Also think about indoor
environments. I’ve come to believe that all
of the attention given to food is really probably misplaced
relative to exposures that occur in indoor environments.
So that in many situations
today, people can be in rooms when they are sprayed by a
licensed applicator. So the exposures that occur
after that often are far, far higher than the exposures
that come from food-borne residues.
The idea that the susceptible
need attention, this is new in environmental
law as of 1996. And new areas that deserve
additional attention that I think are extremely important,
is the use of these chemicals as they’re impregnated into a
variety of consumer products. So if you’re hiking long
distances, you may want a pesticide
impregnated into the fabric that you buy,
if you don’t have an opportunity to wash your
clothes. But what does that mean?
There are a whole new array of
products in the marketplace now that carry these residues,
for obvious functions, such as durability,
keeping them from degrading. Pesticides are added to paints,
for example, to keep the bacteria in paint
from breaking it down and chipping and causing you to have
to repaint in a short period of time.
So that the functional side of
these chemicals used in consumer products is pretty well
understood, but the long-term implications
for environmental quality and human health really are not.
So the underlying problems here
include the human inability to sense chemical risk.
You know, we basically don’t
know where these chemicals are in our environment because we
can’t see them, we can’t taste them,
we can’t feel them. We have to imply where they are
by proxy, thinking about “Gee, I’m living on a tract
of land and I’ve got a well. And this used to be a farmland.
Maybe I ought to test my
drinking water.” Or, “I’m living next to a
field that is planted with a crop that’s routinely sprayed by
a plane that flies over. Maybe the drift is getting into
my environment.” So that thinking about where
these things are in the environment really demands a
certain level of background literacy and knowledge that
often is not present. The underlying problem of lack
of sensitivity to susceptibility is really important.
Who’s susceptible?
Well, the very youngest are.
And remember that all these
concentrations are measured how? They’re expressed per unit of
your body weight. So when in life does a human
have the lowest body weight? In utero, first trimester.
So if the concentration in the
mom is the same moving across the placenta as the
concentration in the fetus, and you get to an exposure
estimate by taking that concentration and dividing it by
body weight, and the mom’s body weight might
be 160 pounds and the fetus’ body weight might be a quarter
of a pound. I’m sorry Laura, about this.
You get the idea.
The same concentration in the
environment affects the fetus much more than it would the
average adult. So this has really transformed
the way that government regulators have begun to think
about chemical management. We’ve had poor monitoring of
chemical release. We have thought much more about
chemical persistence and environmental fate having
learned from strontium-90 and the DDT story.
And we’ve misunderstood
variability in human exposure. Still we’re not putting
monitors on individual people. Although increasingly,
the government is monitoring human tissue,
taking blood and urine and hair samples to try to figure out
what the matrix of chemicals might be that an individual is
exposed to. So looking not just by sampling
in the marketplace, but looking at this pattern by
taking human tissue samples, this is a whole new wave that’s
giving people the opportunity literally to go to a doctor and
say, “I want to be measured for
this entire array of chemicals.”
So it may cost you a couple
thousand dollars to go through that process,
but increasingly people are doing this,
trying to make some sense out of the way that they feel,
their medical condition, and environmental quality.
Single chemical exposure is
still the focus of government. No company wants its chemical
to be compared to another company when they’re making a
regulatory choice. Toxicity testing is incomplete
in a variety of areas, especially relative to the
immune system. And you know the rise in
allergies that we’re experiencing,
severe allergies. More people are walking around
with Epi-Pens today because of worries about anaphylaxis than
ever before. Something is happening to the
human immune system. It’s not clear why,
but many of the chemicals that are released,
such as some pesticides, do influence the human immune
system. That’s one example of an area
of human health that has been neglected by the government.
Also, the endocrine effects are
quite misunderstood. The behavior of these chemicals
as human hormones–that we’ll speak about a bit next week.
Also, failure of labeling as a
management strategy. Labeling is still the dominant
approach that EPA takes to try to inform the public,
to educate the public how they might be able to use these
economic poisons in as safe way. But you need to think about
whether or not that’s really a potentially effective way of
controlling these kinds of risks.
And we’re also misunderstanding
trends in human illness. For example,
we had no asthma registry in Connecticut until 2003.
So we couldn’t figure out
whether or not people that lived in areas that have had higher
levels of air pollution were more likely to have asthma.
So the absence of surveillance
of health conditions makes it impossible to correlate these
exposures to health outcomes. And finally,
a variance in human capacity to manage risk.
There’s a real environmental
justice issue here that needs to be paid attention to,
that there are many members of society that do not have the
capacity to get the education necessary to self-manage risk.
So that some people simply are
more reliant on government standard setting than other
people are. So these are all underlying
problems of law, and all of them are pretty well
exemplified by this history of pesticide management.
Okay, that’s it for today. And we’ll come back on Tuesday.
Have a great weekend.


Leave a Reply

Your email address will not be published. Required fields are marked *