Environmental Politics and Law

EVST 255 - Lecture 9 - Risk and Law: Pesticide Paradigm

Chapter 1. An Introduction to the Relationship between Risk and Law [00:00:00]

Professor John Wargo: 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.

Chapter 2. Evolution of Food and Pesticide Law: 1906 – Present [00:06:07]

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.

Chapter 3. FIFRA Amendments, EPA's Founding and Dietary Diversity [00:21:44]

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?

Chapter 4. Fractured Science, Fractured Law [00:33:54]

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.

Chapter 5. Pesticide Law: A Sequence of Changing Regulatory Priorities [00:40:41]

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. Â 

Okay, that's it for today. And we'll come back on Tuesday. Have a great weekend.

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