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The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop (2016)

Chapter: 7 Obesity Policy Solutions Discussed at the Workshop

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Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
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Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
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Page 124
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 125
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 126
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 127
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 128
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 129
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 130
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 131
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 132
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 133
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 134
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 135
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 136
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
×
Page 137
Suggested Citation:"7 Obesity Policy Solutions Discussed at the Workshop." National Academies of Sciences, Engineering, and Medicine. 2016. The Interplay Between Environmental Chemical Exposures and Obesity: Proceedings of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/21880.
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Page 138

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7 Obesity Policy Solutions Discussed at the Workshop Faiyaz Bhojani of Royal Dutch Shell presided over the last session, which was dedicated to the discussion of policy solutions to reduce exposure to chemicals associated with the development of obesity. A policy, he said, can be thought of as a vision for the future that outlines priorities and the expected roles of the stakeholders and groups. A policy, broadly defined, also includes building consensus and informing people or the public, he said, emphasizing that informing the public is a topic that deserves greater attention than it sometimes gets. A policy needs the commitment of a state, an organization, or other entity to implement it, and it requires not only the laws or regulations that define the policy but also a variety of other mechanisms involved in its implementation. Concerning policies regarding environmental exposures and obesity, Bhojani said, a key question will be whether sufficient and clear evidence should be required before the next step is taken, whether that would be too late and the next steps should be taken in the absence of such evidence, and, if that is the choice, exactly how that would be done. The session consisted of presentations by four speakers1 and then a wide-ranging discussion period involving not just the speakers but the Roundtable members and members of the workshop audience. 1 This summary reflects the order of the presentations as they were given at the workshop, which differed slightly from the workshop’s agenda. 123

124 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY PRESENTATIONS Jeanne Conry The first discussant was Jeanne Conry, the assistant physician chief at Kaiser Permanente, who was representing the American Congress of Obstetricians and Gynecologists (ACOG), where she introduced an agenda on reproductive health and environment. She spoke by phone. As background, she said that ACOG is the nation’s leading group of physicians who provide health care for women. It has about 57,000 members, and it works both to educate physicians and to advocate for policy changes. Obstetricians-gynecologists (OB-GYNs) see themselves as primary care providers, caring for women across their life spans, Conry said. In particular, they see women before, during, and after pregnancy, so they have the opportunity to discuss care with women during these times, which is important in terms of environmental exposures, where many of the critical periods occur during pregnancy or in the first few years afterward. Pregnancy care should be viewed as an investment in the next generation, she said. Research has shown that children are born, in some respects, “prepolluted,” she said. That is, there are harmful environmental chemicals that are ubiquitous, and one study found that 43 chemicals were seen in virtually every pregnant woman in the United States. Furthermore, research has shown that environmental chemicals can cross the placenta, and a number of the environmental chemicals that women are exposed to are known to affect fetal development. Exposure to mercury during pregnancy, for instance, is known to affect cognitive development, and diethylstilbestrol (DES) can even have a transgenerational impact. So it is clear that exposures during pregnancy can have serious effects on a child’s health. In 2013, ACOG and the Society for Reproductive Medicine came out with a committee opinion on reproductive health and the environment designed to educate OB-GYNs. It was based on current research, Conry said, and one of its main messages is that not all exposures are created equal. For instance, underserved and minority populations are dis- proportionately affected by environmental chemicals. And women of reproductive age with occupational exposures to toxic chemicals are particularly vulnerable to adverse reproductive health outcomes.

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 125 The most important point for OB-GYNs to understand about environmental chemicals, Conry said, is that, unlike pharmaceuticals, they enter the marketplace without detailed research on their reproductive toxicity, so not much is known about them in that respect. OB-GYNs do not have to be experts in environmental health, she said, but they should be able to do an intake exam and inform their patients about what their potential exposures are. ACOG’s main policy-centered message in this area is that controlling toxic exposures relies on working toward the greater good, Conry said. Many toxic exposures cannot be controlled by individual actions, and thus, changes in the levels of environmental chemicals generally occur only in response to changes in national policy. So, once ACOG had a committee opinion to work from, it began working at the national and state levels to regulate environmental chemicals. ACOG has identified various policy gaps. An important one is that while pharmaceuticals must be shown to be safe and effective before being used in humans, manufactured chemicals must be shown to be harmful to people before they can be removed from manufacture. This is particularly important to emphasize to OB-GYNs, she said, because while they are familiar with the rules regulating pharmaceuticals, many are not familiar with the world of environmental chemicals, where chemicals are released into the environment without careful study of their effects on humans. That difference is critical in educating physicians on the topic, she said, because they quite often say that they cannot offer advice about environmental exposures because there is no good research on the topic. “They simply don’t understand how different it is between chemical and environmental exposures and that the burden of proof needs to shift,” Conry said. ACOG has several specific recommendations on the topic. First, at the individual level, physicians should educate women to do such things as eat healthy, wash fresh fruits and vegetables, and look at what their exposures are. More importantly, though, it recommends that the U.S. Congress should enact meaningful preventive and protective chemical safety legislation so that the burden of proof is transferred from individuals and physicians to the chemical industry. Specifically, the legislation should identify and reduce exposures to toxic environmental chemicals, should require the U.S. Environmental Protection Agency (EPA) and other federal agencies to take all necessary actions when reviewing substances to guarantee health and safety, and should fund

126 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY rigorous scientific research into the causes and prevention of birth defects. Nearly two-thirds of voters worry about chemicals in consumer products, Conry said, and almost 90 percent support legislation that ensures that products are safe for human use. The support spans demographic and partisan lines, she said. So it is incumbent on everyone in health care each to make their voices heard in support of such action. Sonya Lunder The next presenter was Sonya Lunder, a senior analyst at the Environmental Working Group, a nonprofit advocacy organization. Lunder described the group’s mission to be to evaluate the available scientific information and look for opportunities for policy intervention and also for public education. Concerning environmental chemicals that promote obesity, she said, the good news is that there are ample data that may be used to take action and reduce public exposures to the endocrine disrupters like bisphenol A (BPA), arsenic, and persistent organic pollutants that had been presented as case studies at the workshop. Much is known about these chemicals from research on hormone disruption, she said, and these chemicals are ripe for intervention. The scientific and regulatory communities have generated a great deal of biomonitoring data, and scientists can, in many cases, identify the populations that are at risk. Collectively, scientists can identify the sources of exposure via pathways like consumer products and industrial chemical releases and can state with certainty that people are being harmed by these exposures, particularly because the chemicals are among the better-studied endocrine disrupters. Lunder said that her role as an advocate is not only to learn from the data but also to identify those sources of human exposure to chemicals that are known to be harmful. A major challenge that the public health community faces is that the United States is behind much of the rest of the developed world in its screening of chemicals on the market and in its ability to prioritize out the hazards posed by chemicals. She traced much of the problem to the Toxic Substances Control Act (TSCA) of 1976, which grandfathered in 62,000 chemicals that were already on the market and were assumed to pose no unreasonable risk to human health or the environment. “We obviously see that that is not a safe assumption

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 127 to make about the chemicals that were in widespread use at that point,” she said. EPA faces an incredible burden in trying to take action on those chemicals that were grandfathered in, and so far, under its authority under TSCA, it has been able to ban only polychlorinated biphenyls. The agency also faces a challenge in its screening of new chemicals, she said. Its new chemical program has only 90 days to evaluate chemical applications, and about half of the new chemicals submitted have very little or no data about physical or chemical properties and health endpoints. And, in reality, the companies have little incentive to develop those data because then they would have to be disclosed for the new chemical submission process. “EPA has approved 40,000 new chemicals since TSCA was enacted,” Lunder said, “and the names and basic identities of these chemicals are, in many cases, trade secrets and not disclosed—even within EPA, let alone to the greater research world or to the public.” Furthermore, because there is a rapid turnover in the chemical market, 20 percent of the high-volume chemicals in one reporting cycle actually are not even produced in significant volumes in the next. So one very important policy need is finding a way to rapidly screen and address chemicals during the period of time that they are on the market, given that there will always be an influx of new chemicals. Still, despite these problems, Lunder said, she believes that environmental interventions hold great promise in averting health problems such as obesity and other metabolic disorders. The reason is that, unlike attempts to change individual behavior practices, which often revert to the original practices even after changes have been made, environmental interventions have the potential to create permanent changes that affect an entire population. In many cases, she said, environmental interventions have been cost-effective ways of reducing exposure to hormone disrupters. Even in the absence of governmental actions, there can be effective responses to the presence of environmental chemicals, Lunder said. The general public is incredibly concerned about the role of environmental chemicals in health, and this has resulted in some rapid changes in the marketplace, such as the removal of BPA from the liners of baby formula containers. Liquid baby formula was commonly sold in cans whose linings contained BPA, resulting in low levels of BPA in baby formula, a product that could be 100 percent of a child’s diet for the first 6 to 12 months of life. The removal of BPA from the liner of baby formula cans

128 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY is a great example of a quick market change that could drastically reduce exposure during a critical period, she said. In addition to such positive moves as the ban on phthalates in some children’s products, some hard lessons about the complexities of making chemical substitutions have also been learned, Lunder said. For example, she said, a number of savvy consumers began to avoid products with high levels of high-fructose corn syrup, which led to an increased use of organic brown rice syrup as a sweetener in many processed foods. “And now we are realizing that rice, and especially brown rice, is loaded with arsenic,” she said, “so people who are buying supposedly more healthy processed food are actually buying food with arsenic in it.” The Environmental Working Group, Lunder said, has been working to identify the most obvious problems concerning consumer exposures, problems for children, and the safety of the food supply and trying to fix them. It has, for example, been performing product testing to identify the presence of various chemicals in foods as a way of raising awareness among consumers and researchers. It has developed several apps for consumers that are intended to highlight the widespread use of endocrine-disrupting chemicals, including an online database of about 80,000 food products, and a similar app that rates cosmetics, soaps, and lotions. It has written numerous public comment letters and lobbied on behalf of TSCA reform for the support of research and biomonitoring for toxic chemicals. “I would like to encourage you guys to join us in this effort,” she said. Finally, Lunder commented that Kristina Rother’s statistic about the role of soda in promoting obesity—that drinking only a soda or two per day is associated with a significant increase in body mass index over a long period of time—is very helpful for the public to hear, and it could be very motivating for some people. That sort of clear information that pinpoints problems and helps people prioritize in a nonjudgmental way is really helpful, she said. Researchers should strive to provide more such information. Judy LaKind The next discussant was Judy LaKind, the president of LaKind Associates and an adjunct associate professor in the Department of Epidemiology and Public Health at the University of Maryland School of Medicine and the Department of Pediatrics at the Milton S. Hershey Medical Center. She spoke by phone.

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 129 LaKind described a systematic review of the epidemiological literature on the relationship between chemical exposure and obesity and obesity-related illnesses that she and her colleagues carried out. In particular they examined BPA, phthalates, and their associations with obesity, diabetes, and heart disease. The papers appeared in Critical Reviews in Toxicology in 2014 (Goodman et al., 2014; LaKind et al., 2014a). Showing a slide that included all the studies that had been published at the time of the review of BPA and obesity, LaKind illustrated the range of results that had been observed. From the slide, she noted, it was obvious that there had been a large number of studies on the subject but also that the results had been inconsistent. In individual studies there were many times when the authors found inconsistent results, depending on how obesity was assessed, LaKind said, and there were also inconsistencies in results across studies when authors used the same approach for assessing obesity. “So, when you look at the totality of the data, I think what you will see is that it neither supports nor refutes the hypothesis of an association between BPA and obesity,” she said. In the case of the relationship between BPA and diabetes, there were fewer studies but still a substantial number of them, and again, there was a great deal of inconsistency in results across studies. LaKind and her colleagues observed similar inconsistencies for reports on associations between urinary BPA levels and various types of assessments for heart disease. Similar inconsistencies were found for studies examining associations between the levels of phthalate metabolites and obesity, type 2 diabetes, and cardiovascular disease. Overall, the literature does not shed light on whether BPA or phthalates are associated with these three health outcomes. There are various reasons for this problem, LaKind said. One issue is that these studies are focused on short-lived chemicals. Researchers are quite good at measuring and interpreting data on persistent chemicals, such as dioxins, but best practices for measuring and interpreting biomonitoring data on short-lived chemicals are in the early stages (LaKind et al., 2014b), and studies often include measures that are unlikely to properly capture exposures that are relevant for the time frame of interest (LaKind et al., 2012). In the studies that she and her colleagues looked at, too few samples were generally taken to capture the variability that occurs from hour to hour and day to day or over longer

130 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY periods of time. Many of those papers acknowledged that this was a problem, she said. A second problem arises from matrix adjustment issues. Many of the studies look at urinary measures of chemicals, and it is known that urine dilution varies from person to person and day to day. LaKind pointed out that the best approaches for accounting for these variations are still debated. The method used can have a significant effect on the analyses of associations between exposure and outcome, and, indeed, depending on the method used for matrix adjustment, it is possible to get completely different associations from the same data (Goodman et al., 2014; LaKind and Naiman, in press). A third issue is the lack of consistency in study design (LaKind et al., in press). This makes it very difficult to compare one study with the next. Yet another issue is that most researchers performing these studies have not taken diet into account as a confounding variable, yet diet is one of the main exposure pathways for BPA, and diet is also critical to understanding obesity and obesity-related disease. The take-home message, LaKind said, is that research that promotes and provides higher-quality exposure estimates should be supported if this research is to be useful in public health decision making. Sheela Sathyanarayana The last presenter was Sheela Sathyanarayana, an associate professor of pediatrics in the Department of Environmental and Occupational Health Sciences at the University of Washington and chair of EPA Children’s Health Protection Advisory Committee. She was representing the American Academy of Pediatrics at the workshop. She began by describing some of the characteristics of good environmental policy. To start, it should take all stakeholder opinions into account. It should be well written, concise, and easy to understand. In particular, because many members of the public have a difficult time understanding environmental exposures, policy needs to be written in a way that they can easily understand and that allows them to implement it in their daily lives. It can be very difficult to write a policy that is effective in achieving its goal, Sathyanarayana said. Many times policies are put into place without evidence about whether they will be effective, and it is only years later, after studies have been done to examine the results, that it becomes clear that they were not effective.

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 131 Good environmental policy should consider the weight and strength of the evidence. Without concrete evidence concerning the harms of different chemicals, one can use screens to detect and prioritize chemicals and then do a risk assessment to estimate the various risks. Risk assessment is at the core of a lot of environmental policy that gets put into effect, Sathyanarayana said. Good environmental policy should also take into account a cost– benefit analysis. This should include the cost of imposing the regulation but also the cost of doing nothing. Who should be putting forth the policy? There are many possibilities: medical schools can carry out changes in medical school curricula. The American Academy of Pediatrics could revise its guidelines to clinicians. And even within an organization it is not always clear who should put forth the policy. Within the American Academy of Pediatrics, for example, it could be the Council on Environmental Health, the Council on Endocrinology, or perhaps representatives from the entire organization. The individual states can put policies in place. Sathyanarayana explained that Washington State has placed limits on the amounts of certain chemicals that can be in children’s products to protect their health. “But I can say, having sat on the governor’s committee to implement these regulations, it is really difficult to implement on the ground level,” she added. The federal government can also put policies into place. For instance, the Chemical Safety Improvement Act was introduced in the Senate in 2013 to reform TSCA, but it has not been moving forward. To conclude, Sathyanarayana spoke about the difficulties of making a difference through changing individual behavior. She works with the Pediatric Environmental Health Specialty Unit, a national organization of networks across the country that does environmental health consults for families. It provides a document that offers various recommendations on how to reduce exposures to phthalates and BPA: buy low-fat dairy products such as skim milk and low-fat cheeses, buy fresh or frozen fruits and vegetables when possible, avoid canned and processed foods, and so on. The document also recommends to people that they avoid certain plastics and, ideally, to use stainless steel or glass when possible. To determine how effective it is to provide families with written guidelines on reducing exposures to phthalates and BPA, Sathyanarayana and colleagues performed a study. They recruited 10 families with two children between the ages of 4 and 8 years. Half got a catered dietary

132 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY intervention, and the other half got educational handouts. They expected that the half with the catered intervention would have lower levels of phthalates and BPA at the end of the trial because they were eating food that was carefully prepared to avoid contact with materials containing these chemicals. On the other hand, they expected that the half given the written guidelines would show little or no change because they were unlikely to change their food preparation and eating patterns significantly. What they found at the end of the trial, however, surprised them. The half given the educational handouts showed no change, as expected, but the half given the catered meals showed a large increase in phthalate concentrations in their blood. It turns out that the ground coriander used in preparing the catered meals had a huge amount of phthalate in it. The lesson is this: it can be very difficult to advise people on how to avoid these exposures because even the most careful, doctor-designed programs may not do what they are expected to do. DISCUSSION The discussion period began with a question from a Web audience member, Janet Young, who referred to Judy LaKind’s comments about inconsistencies in studies on the effects of environmental chemicals and commented that in 2009 Chemical and Engineering News reported that gut bacteria influence the toxicity and effectiveness of pharmaceuticals. Her question was, Wouldn’t the individual gut microbiome signature affect the toxicity of exogenous chemicals and, therefore, research outcomes? LaKind responded that it is not an area she works in, so she could not speak to the issue directly, but there are dozens or even hundreds of different factors that affect the outcomes that are observed. However, she added that it would not surprise her if the microbiome was found to play a role and add to the complexities in examining exposure–outcome associations. Lynn Goldman of George Washington University agreed with LaKind, saying that she has reviewed many of these studies herself, and the exposures that are likely of most importance—those that have occurred over years or decades or even prenatally—are generally not the exposures that can be measured. The studies end up measuring more immediate, short-term exposures, which do not provide any sense of the cumulative burden. Linda Birnbaum of the National Institute of Environmental Health Sciences also agreed, commenting that many human epidemiological

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 133 studies of the short-lived chemicals, even if they are longitudinal, are often based on a single urine measurement, and it is well known that for some of the short-lived chemicals, this can be completely misleading. There are some studies with BPA levels that indicate that it requires at least four to seven urine measurements to have any idea of what the average urine levels may be, and even then there may be no good idea of what the peak concentrations are, which may also be important. Sheela Sathyanarayana commented that it is known that the highest exposure concentrations for many of these chemicals, because they are derived from the diet, come at night after an entire day of eating. Thus, when they do their studies they ask their study participants to get samples at night. Most of the epidemiological studies do not do this, however, so Sathyanarayana estimated that the exposure estimates are underestimating the actual body burdens by a significant amount. Dennis Devlin from ExxonMobil said that one of the concerns that has been expressed in a small industry group that has been working on revisions to the TSCA is whether EPA will find it too difficult to declare that chemicals are safe for human use, which is one of the approaches that many are calling for in the revision of TSCA. Because EPA’s culture is designed more for saying no to hazardous chemicals, he suggested, the agency might have a difficult time saying, “Yes, this chemical is completely safe.” One particular concern is that EPA might be swayed by the history of chemicals that were once thought to be safe and that later turned out to threaten health or the environment in one way or another. So, he asked, will this proposed new role for EPA demand a tremendous cultural change at the agency, and how difficult will it be to create that change? Goldman answered that, having served as an assistant administrator at EPA, she does indeed believe that EPA is capable of making such judgments; indeed, it already makes such decisions in a variety of situations, as in determining significant new use rules. The real challenge for EPA, she said, is identifying which chemicals are likely to be bioactive and to pay much more attention to those and their intended uses. Nor did she think that EPA will be particularly bothered by the possibility that a chemical judged to be safe at one point turns out years later to have unexpected consequences. “Is it possible the judgment will change? Well, I hope so. Science moves onward, and things do change, so I think that is important.” She added that she believes that the U.S. Food and Drug Administration (FDA) will have to be part of the big picture of regulating

134 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY various chemicals that may play a role in obesity. If a chemical is used as a food additive, for example, EPA is not allowed to regulate that use; instead, FDA must decide on its safety. “So the capacity of FDA to be able to scrutinize those [chemicals] and, if you may, the willingness of FDA to use its authority to look at those [are] extremely important,” she said. Reforming TSCA may be necessary for improvement in this area, but it will not be sufficient. FDA will also have to pay attention to such chemicals. Furthermore, she added, the private sector has a major role to play in all of this as well. It has already been demonstrated how market demand can influence such things as the presence of BPA in food containers, but it is also the case that a number of corporations are moving away from some of these substances on their own. Johnson & Johnson, for example, took the formaldehyde out of its baby shampoos without any order from EPA. Thus, many changes may be made without the creation of new regulations, but those changes will not come quickly enough, she said, as long as there are such large gaps in knowledge about these chemicals. Frank Loy commented that TSCA reform is the biggest single legislative effort that the health community and the environmental community are going to see but that it will inevitably be a bipartisan effort, which means that, from the health community’s point of view, it will not be the absolutely ideal bill. It is going to have serious flaws, he said. Thus, the health community and the nongovernmental organization community will have to decide whether it is good enough. It is impossible to predict exactly what the bill will look like, but it will not satisfy everybody. One of the things that the bill will have, he predicted, is preemption; that is, it will prohibit certain state-level rules or certain future state-level rules from making some tests tougher than the level set forth in the bill itself. “We are going to have to make decisions like that,” he said, “and I would just say, having been in the game of politics for a while … if we do not get a bill this time, we are not going to get one for another x years. So taking an imperfect bill and dumping it is probably going to leave us where we are for a very long time.” Nsedu Witherspoon of the Children’s Environmental Health Network asked for some key messages that public health and child health policy advocate communities may be able to prioritize and rally around to reduce some of these exposures and related health outcomes. Sonya Lunder suggested targeting some “egregious” uses of endocrine-disrupting chemicals in consumer products. As examples, she

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 135 pointed to the polyvinyl chloride (PVC) used in medical tubing and also in food processing. Much of the contamination in food happens during the processing stage, she said, so getting the PVC out is of critical importance. “I think we have reached the point where that should be a no-brainer,” she said, “and I would love everybody’s help on that.” Birnbaum cautioned, however, that one must think carefully about alternatives. Newborns in the neonatal intensive care unit may be particularly vulnerable to the diethylhexyl phthalate softener used to make PVC medical tubing, but they still require some sort of tubing in their treatment, and whatever is chosen as a substitute may have its own, lesser-known problems. Concerning the issue of key messages, Goldman suggested that one bit of advice for parents is that they should themselves take control over different aspects of what their children are exposed to. For instance, they should pay attention to the commercial advertising that their children see—during Saturday morning children’s programming, for instance— because many of those commercials are for junk food, and studies have shown that young children are not critical about advertising messages. Parents should also take control over what their children are served at school, she suggested. They should work to get the sodas and the junk food out and the fresh fruits and vegetables in. Henry Anderson of the Wisconsin Division of Public Health said that it would be very useful for consumers to have an idea of exactly where different chemical exposures are coming from. It would be very helpful, for instance, if the public were told whether they should worry about eating canned food or whether they need to worry about food that has been kept in plastic containers for several days. LaKind responded that she thought that this was a very good point. With the advent of biomonitoring, it has become possible to get very good measurements of what a person has been exposed to, but it is often difficult to interpret all those data because the idea of source apportionment—knowing exactly how much exposure is coming from each type of source—has been lost. While the traditional methods of exposure science, which inherently included source apportionment, might feel outdated to some people, she said, they are extremely important and capture information not available from biomonitoring. Sathyanarayana commented that such source apportionment can be very complicated for a number of reasons, one of which is that manufacturers change their formulations constantly. In personal care products, for example, the concentration of chemicals tested one year may

136 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY be different in the exact same product when tested the next year, she explained. It is the same with foods, she added. There are often changes in processing over time, which changes the sorts of chemicals that the foods are exposed to—and contaminated with—during processing, so it can be difficult to say exactly where certain chemical exposures arise. Linda McCauley of Emory University asked if any of the clinicians at the workshop might comment on the best ways for health practitioners to talk with members of the public about the various issues related to environmental exposures and obesity. Jeanne Conry replied that ACOG is working with its board certification unit to provide information for physicians to read as part of their board certification so that they are exposed to and understand some of what is going on in this area. It is an incremental process, she said, working with the board certification and then with the education of medical students and with the education of residents. Sathyanarayana described the sort of scenario that she might see in her clinic and how she deals with it. An obese 5-year-old is visiting the clinic, and Sathyanarayana has about half an hour with him or her. She first talks about the growth curve, making sure that the parents understand that the child is gaining weight at a rate that is more rapid than normal and making sure that they understand what obesity is, why it is important, and what it can lead to. Then she talks about the child’s diet. If there are obvious problems—such as one case where the family was consuming five 2-liter bottles of soda every week—she explains what they should be doing instead. And she also talks about other things to do around the home to keep the child safe and reduce exposures. LaKind offered two closing thoughts. First, she suggested that in doing studies of the effects of environmental exposures and obesity, it will be important for the research teams to include exposure scientists, who could offer valuable expertise and insights. Second, she reiterated an earlier point that it will be important to be careful with alternative products. Otherwise, there may be a move to alternatives that end up posing a greater risk (LaKind and Birnbaum, 2010). Sathyanarayana referred back to the observation that evaluation of the interplay between environmental exposures and obesity is a broad, multidisciplinary field, and she said that just as attacking its issues will require researchers from different areas to work together, coming up with effective policies will require policy makers to work together to come up with comprehensive policies that address all the different aspects of obesity management—not just the environmental exposures but also all

OBESITY POLICY SOLUTIONS DISCUSSED AT THE WORKSHOP 137 the other components that were not specifically addressed in the workshop. Goldman said that she had been struck by the differences in the federal response to, on the one hand, issues of physical activity and diet and, on the other hand, issues related to environmental exposures and obesity. For the first, she noted, there has been remarkable White House leadership, with the First Lady being very engaged, bringing together people from federal agencies, foundations, and industry to work on the issue. But the second issue has not been a part of that. The question, then, is how to get issues related to environmental exposures and obesity to be considered part of that broader effort to fight obesity. Dealing effectively with environmental exposures and obesity will require an effort broader than that which has been waged to date, she said. “It needs to bring in more of the science, and it needs to bring in FDA, EPA, and others to be able to assume their responsibilities in this…. So we have a way to go before we have a policy framework that actually is addressing these issues.” REFERENCES Goodman, M., J. S. LaKind, and D. R. Mattison. 2014. Do phthalates act as obesogens in humans? A systematic review of the epidemiology literature. Critical Reviews in Toxicology 44(2):151–175. LaKind, J. S., and L. S. Birnbaum. 2010. Out of the frying pan and out of the fire: The indispensable role of exposure science in assessing replacement chemicals. Journal of Exposure Science and Environmental Epidemiology 20:115–116. LaKind, J. S., and D. Q. Naiman. In press. Changes in bisphenol A exposure in the United States from 2003–2012, factors associated with BPA exposure, and effect of creatinine adjustments. Environmental Research. LaKind, J. S., M. Goodman, and D. Q. Naiman. 2012. Use of NHANES data to link chemical exposures to chronic diseases: A cautionary tale. PLoS ONE 7(12):e51086. LaKind, J. S., M. Goodman, and D. R. Mattison. 2014a. Bisphenol A and indicators of obesity, glucose metabolism/type 2 diabetes and cardiovascular disease: A systematic review of epidemiologic research. Critical Reviews in Toxicology 44(2):121–150. LaKind, J. S., J. R. Sobus, M. Goodman, D. B. Barr, P. Fürst, R. J. Albertini, T. E. Arbuckle, G. Schoeters, Y. M. Tan, J. Teeguarden, R. Tornero-Velez, and C. P. Weisel. 2014b. A proposal for assessing study quality: Biomonitoring, Environmental Epidemiology, and Short-Lived Chemicals (BEES-C) instrument. Environment International 73C:195–207.

138 ENVIRONMENTAL CHEMICAL EXPOSURES AND OBESITY LaKind, J. S., M. Goodman, S. L. Makris, and D. R. Mattison. In press. Environmental epidemiology harmonization to improve public health decision-making: A three-part proposal. Journal of Toxicology & Environmental Health, Part B.

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In March 2015, the National Academies of Sciences, Engineering, and Medicine held a workshop to explore the role that chemical exposures may play in the development of obesity. The obesity epidemic that has gripped the United States and much of the developed world for the past several decades has proved remarkably resistant to the various approaches tried by clinicians and public health officials to fight it. This raises the possibility that, in addition to the continued exploration of consumer understanding and behavior, new approaches that go beyond the standard focus on energy intake and expenditure may also be needed to combat the multifactorial problem of obesity.

The speakers at the workshop discussed evidence from both studies with animal models and human epidemiological studies that exposure to environmental chemicals is linked both to weight gain and to glucose tolerance, insulin sensitivity, inflammation, and other aspects of the metabolic syndrome. In addition to conventional environmental chemical exposures, this workshop also included one panel to discuss the potential role of other exposures, including sugar, artificial sweeteners, and antibiotics, in aiding or causing obesity. The participants also examined possible biological pathways and mechanisms underlying the potential linkages. This publication summarizes the presentations and discussions from the workshop.

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