EHP: The Researcher's Perspective

We live in a time when investigators have overwhelming amounts of health-related data at their fingertips. In this podcast, Nicole Kleinstreuer explains how environmental health scientists are using machine learning to make sense of the information in those data—for example, predicting toxicological end points based on large curated data sets. But even as machine learning advances, researchers are working to set realistic expectations and performance thresholds for these new methods. Visit the podcast webpage to download the full transcript of this podcast. 

Methylmercury, the most toxic form of mercury, is found in seafood around the world, and it can cause severe health effects in people who are exposed to it. Governments are working to reduce the amount of mercury that finds its way into the environment. Dozens of countries have pledged to implement measures to reduce mercury pollution. In this podcast, Niladri Basu discusses his recent systematic review, which estimates global baseline mercury exposures. These estimates will help countries gauge the success of their control measures. Visit the podcast webpage to download the full transcript of this podcast.

Can living in green surroundings make you healthier and happier? It’s a tantalizing idea. In this podcast, guest Rachel Banay discusses her recent EHP study on depression in older women in relation to the amount of greenness near their homes. The study is part of a growing body of research that suggests there may, in fact, be health benefits associated with spending time in or near green spaces—although it is too soon to draw any firm conclusions about the nature and direction of the relationship, if it exists. Visit the podcast webpage to download the full transcript of this podcast. 

It would be nearly impossible using current methods to test all the chemicals in use for toxic effects. So how do we prioritize which ones to study? In this podcast, Martyn Smith describes how he and his colleagues are developing lists of “key characteristics” shared by toxicants that cause specific adverse health effects, such as cancer or male or female reproductive toxicity. Risk assessors can use this information to predict the toxicity of other chemicals in an organized, systematic way. This approach may be useful in prioritizing chemicals for more detailed evaluation. Visit the podcast webpage to download the full transcript of this podcast. 

For some people, the whoosh of wind turbines is the sound of clean energy. For others, it is the sound of an environmental exposure that could possibly cause adverse health effects. Wind turbine noise has been studied in relation to diabetes, hypertension, preterm birth, and more. In this podcast, Aslak Harbo Poulsen discusses his research on wind turbine noise in relation to two more outcomes: likelihood of filling prescriptions for sleeping pills or antidepressants, and risk of heart attack or stroke. Visit the podcast webpage to download a full transcript of this podcast. 

DuPont introduced GenX almost 10 years ago as a chemical substitute for perfluorooctanoic acid (PFOA). Although GenX was intended to be less environmentally persistent than PFOA, it has turned out to be what is known as a “regrettable substitute,” whose effects may be as bad as or even worse than the chemical it replaced. In this podcast, guest Jane Hoppin discusses her work assessing exposures to GenX and related chemicals in people living in the Lower Cape Fear River Basin of North Carolina. Visit the podcast webpage to download the full transcript of this podcast.

Although obesity is a major risk factor for diabetes, certain environmental agents, such as arsenic, also appear to contribute to the disease. There is evidence that an individual’s risk of arsenic-related disease depends on how efficiently he or she metabolizes arsenic. But what if that individual is both obese and exposed to arsenic? In this podcast, guest Mirek Stýblo discusses his recent work exploring the role that diet plays not just in arsenic metabolism but also in the diabetogenic effects of arsenic. Visit the podcast webpage to download the full transcript of this podcast.

Several studies have reported links between asthma in children and the presence of phthalates in dust from the children’s homes. But the presence of a chemical is not the same thing as exposure, so Norway’s Environment and Childhood Asthma Study has taken the research a step farther by measuring phthalates in the urine of children with and without asthma. In this podcast Randi Bertelsen discusses her recently published findings. Visit the podcast webpage to download the full transcript of this podcast.

When you think about the health effects of air pollution, what comes to mind? Lung disease? Cancer? One health effect you might not immediately think of is low birth weight, a risk factor for a variety of other health problems later in life. Yet a growing body of evidence indicates that birth weight and other gestational outcomes can be influenced by a mother’s exposure to fine particulate matter air pollution. In this podcast Tracey Woodruff discusses new findings on this link from a global consortium of investigators who, between them, have analyzed more than 3 million births. Visit the podcast webpage to download the full transcript of this podcast.

Your bulges are busier than you may think…Many people see adipose tissue—fat—as nothing more than lumpy extra baggage. But fat serves several important functions in the body. It helps us store energy and endocrine hormones that can affect behavior, energy regulation, immune and vascular function—to name a few. It also protects against toxic effects of persistent organic pollutants, or POPs. In this podcast, Michele La Merrill talks with host Ashley Ahearn about the diverse ways that fat interacts with these chemicals as both a modulator and a target of POP toxicity. Visit the podcast webpage to download the full transcript of this podcast.

Despite dramatic decreases in atmospheric lead levels over the past few decades, lead exposure remains a problem, especially for children. In this podcast, Marie Lynn Miranda discusses one remaining, albeit relatively minor, source of lead exposure: leaded aviation gasoline. Visit the podcast webpage to download the full transcript of this podcast.

Arsenic is a problem in communities around the world, from Bangladesh to New Hampshire. It’s one of the environmental chemicals the National Toxicology Program explored at a recent workshop as possibly contributing to the worldwide rise in diabetes. In this podcast, Ana Navas-Acien talks about a new review by investigators at that workshop, who summarize the evidence for a link between arsenic exposure and diabetes. Visit the podcast webpage to download the full transcript of this podcast.

New Orleans is already known as a hot, moist place—ideal growing conditions for mold. Now factor in Hurricane Katrina, which hit the city in August of 2005, leaving behind even more indoor mold and other asthma-causing allergens. Host Ashley Ahearn talks with Patricia Chulada about research to study and improve post-Katrina asthma symptoms in the children of New Orleans. Visit the podcast webpage to download the full transcript of this podcast.

Children whose mothers smoked during pregnancy are more likely to have problems like low birth weight, asthma, and possibly obesity, cancer, and high blood pressure. For clues into the mechanism behind these effects, scientists are looking to the epigenome, the personalized set of directions that tells our cells how and when to produce proteins, which is one of the ways gene activity is controlled. In this podcast Stephanie London and Bonnie Joubert discuss the results of their recent study in which they identified a set of genes with methylation changes present at birth in children whose mothers smoked during pregnancy. Visit the podcast webpage to download the full transcript of this podcast.

Over the past million years humans have migrated in response to food shortages, droughts, ice ages, and many other reasons, but in the coming decades, migrations related to climate change are expected to increase, perhaps dramatically. Different circumstances—be it forced displacement, a planned resettlement, or migration into a city—can present different humanitarian and health adversities, but population movements also can offer benefits for migrants themselves, the communities they left, and the communities where they land. In this podcast, Celia McMichael and Jon Barnett tell host Ashley Ahearn about research and policy steps needed in advance of the rising tide of climate change–related migration. Visit the podcast webpage to download the full transcript of this podcast.

Human beings, as a species, are putting on weight. Obesity rates are rising in rich and poor countries alike for a variety of reasons, from changing dietary habits and activity levels to exposure to artificial nighttime light. Mounting evidence from over the past decade suggests that certain chemicals may be playing a role as well. For some people, so-called obesogens may be altering their metabolism and fat cell development, making it harder to maintain a healthy weight. In this podcast, host Ashley Ahearn talks with Bruce Blumberg about the state of our understanding of obesogens. Visit the podcast webpage to download the full transcript of this podcast.

Reproduction, growth, behavior, and sleep patterns are just a few of the bodily functions controlled by hormones. Researchers around the world are examining what happens if chemical substances we’re exposed to in our daily lives interrupt or imitate natural hormonal messages. The body of scientific evidence so far suggests that even at very low doses, exposures to endocrine disruptors may have very real effects, and that low-dose effects may disappear at higher doses, giving an illusion of safety if chemicals are not tested at low-enough doses. In this podcast, host Ashley Ahearn talks with Laura Vandenberg about her recent review of the evidence on health effects of low-dose exposures to endocrine disruptors. Visit the podcast webpage to download the full transcript of this podcast.

Many organic foods and high-energy products are sweetened with brown rice syrup as an alternative to high-fructose corn syrup. Consumers who eat these products may be avoiding high-fructose corn syrup, but they also may be exposed to arsenic that's been absorbed by the rice plants from which the syrup is made. In this podcast, Kathryn Cottingham talks with host Ashley Ahearn about her recent market-basket study of products containing brown rice syrup and other rice-based ingredients. Arsenic was detected in all the products tested, although Cottingham cautions it's too soon to say what this means in terms of potential health effects. Visit the podcast webpage to download the full transcript of this podcast.

Burning forests, grasslands, and fields have been part of the landscape probably for as long as humans have been on the planet. But it's only in recent years that we've begun to explore the health effects of exposure to landscape fire smoke, which is now known to exacerbate preexisting disease and induce new disease. In some parts of the world, people are chronically exposed to smoke from landscape fires that burn for a large portion of the year. In other areas, exposure is sporadic and short-term. In this podcast, host Ashley Ahearn talks to Fay Johnston and Sarah Henderson about their their study in which they estimate the number of deaths worldwide attributable to smoke from landscape fires. Visit the podcast webpage to download a full transcript of this podcast. 

Americans are widely exposed to phthalates in soft plastic products from toys to medical equipment. A perhaps lesser-known potential source of exposure is the timed-release coatings on certain pharmaceuticals and dietary supplements, which enable active ingredients to reach the correct part of the gastrointestinal tract for working properly. In this podcast, host Ashley Ahearn talks to Katherine Kelley about her new study on the extent to which phthalates are used in medicinal products. Visit the podcast webpage to download a full transcript of this podcast.

Hydraulic fracturing ("fracking") is a controversial practice used in natural-gas drilling. Fracking makes it much more feasible to free the vast reserves of natural gas locked underground, but the practice comes with concerns that the natural gas boom is proceeding too fast, before we understand the human health impacts. Discussions about fracking and community health typically involve questions about methane contamination of drinking water wells around drill sites. In this podcast, host Ashley Ahearn talks with Robert B. Jackson about another fracking-related water concern: the millions of gallons of contaminated wastewater generated by the process. Visit the podcast webpage to download a full transcript of this podcast.

In our daily lives we're rarely exposed to just one chemical at a time. Metals, for example, are ubiquitous in the environment, and most of us are exposed to different combinations of metals each day through air, water, and food. Simultaneous exposures to different metals may have synergistic effects in children, whose developing brains are particularly vulnerable to adverse effects from these potentially neurotoxic agents. In this podcast host Ashley Ahearn discusses the neurodevelopmental effects of metals mixtures with researcher Robert O. Wright. Visit the podcast webpage to download a full transcript of this podcast.

With more than 1 billion people estimated to not have enough to eat, food security is a pervasive problem. An estimated one-third of the global burden of disease afflicting children under the age of 5 is caused by undernutrition. Climate change is anticipated to reduce cereal yields, further threatening food security and potentially increasing child undernutrition. In this podcast, host Ashley Ahearn discusses the connection between climate change and undernutrition with researcher Sari Kovats. Visit the podcast webpage to download a full transcript of this podcast.

Cell phones have become an integral part of many people’s lives. But could our constant contact with these devices be affecting our health? That question has been the subject of international debate and intense study in recent years. In this podcast, David Savitz of Brown University discusses evidence from epidemiologic studies of cell phone safety with host Ashley Ahearn. Visit the podcast webpage to download a full transcript of this podcast.

Studies are showing a trend of girls developing breasts and going through puberty earlier than they did in years past. Now researchers are investigating the role environmental exposures may play in this trend and the potential long-term health effects of earlier development. In this podcast, host Ashley Ahearn discusses with researcher Suzanne Fenton how research on environmental exposures and mammary gland development in rodents might be used to assess risks for humans. Visit the podcast webpage to download a full transcript of this podcast.

Climate change is not just a problem for rivers and reservoirs that are running dry, or forests and grasslands that are seeing an increased incidence of wildfire, or Arctic wildlife stressed by rapidly changing ecosystems. It’s a problem for human health, too, as John Balbus discusses with host Ashley Ahearn. It can be tricky to attribute specific health effects to climate change, which reflects trends in the weather averaged over decades. But short-term weather fluctuations are known to alter the risk of several diseases. As short-term fluctuations become long-term patterns, health effects also may adopt new patterns. Visit the podcast webpage to download a full transcript of this podcast.

In the 2007 news feature "Waste Couture: Environmental Impact of the Clothing Industry," EHP explored the environmental and occupational health implications of producing cheap—indeed, virtually disposable—clothing. This story has gone on to become the journal’s most popular article of all time. Author Luz Claudio tells host Ashley Ahearn about the inspiration for "Waste Couture," why this story has captured so much attention, and changes she has seen in fashion since its publication. Visit the podcast webpage to download a full transcript of this podcast.

The Tohoku earthquake and tsunami of 11 March 2011 devastated entire swaths of the Japanese coastline and killed thousands of people. Much of the attention following the disaster has focused on radiation exposures from the damaged Fukushima Daiichi nuclear power plant. Now public health officials are beginning to assess another potential source of disaster-related exposures: hazardous chemicals that may have been released when major industrial centers along Japan’s east coast were damaged or destroyed. In this podcast, journalists Lizzie Grossman and Winnie Bird talk with host Ashley Ahearn about their EHP feature story on the potential chemical contamination following the Tohoku disaster. Visit the podcast webpage to download a full transcript of this podcast.

Air pollution in China, one of the world’s oldest civilizations, reflects a combination of traditional and modern-day factors. Severe air pollution in Chinese cities is the result of rapid industrialization, urbanization, and growth in vehicle use. At the same time, traditional indoor burning of solid fuels such as coal and dung presents acute, severe exposures to pollutants including particulate matter, carbon monoxide, arsenic, and mercury. In this podcast, Junfeng (Jim) Zhang tells host Ashley Ahearn about some of the factors that make air pollution a significant problem in China. Visit the podcast webpage to download a full transcript of this podcast.

Biomonitoring studies reveal what we've been exposed to, but the significance of these exposures is not always clear—and when the participants in such studies are children or pregnant women, this lack of certainty can be especially unnerving. Reporting body burden findings back to study participants and to the general public therefore poses major ethical and logistical dilemmas, as Tracey Woodruff and Rachel Morello-Frosch discuss with host Ashley Ahearn. Visit the podcast webpage to download a full transcript of this podcast.

The International Agency for Research on Cancer, the National Toxicology Program, and the Environmental Protection Agency all declared asbestos a known human carcinogen decades ago. Yet U.S. imports of crude chrysotile asbestos fibers rose by 235% between 2009 and 2010, and use is also on the rise in many industrializing, developing countries. Richard Lemen tells host Ashley Ahearn what's driving this growth and how asbestos is currently used worldwide. Visit the podcast webpage to download a full transcript of this podcast.

In honor of its fiftieth anniversary the Society of Toxicology teamed up with the National Institute of Environmental Health Sciences, the National Toxicology Program, and Environmental Health Perspectives to produce a poster celebrating some of the foremost "benchmarks" of the field. In this podcast Peter Goering tells host Ashley Ahearn how he and other members of the evaluation group chose from centuries' worth of accomplishments to select the people and events that best illustrate the promise and achievements of toxicology. Visit the podcast webpage to download a full transcript of this podcast. 

Bisphenol A (BPA) is used in a wide variety of consumer products, and biomonitoring studies indicate widespread exposure to the compound. Much of the hesitation to regulate BPA up to now has stemmed from uncertainty about whether health effects reported in laboratory animals—which include heart disease, obesity, diabetes, reproductive health problems, and several types of cancer—can be extrapolated to humans. In this podcast, Frederick vom Saal discusses recent findings that suggest mice, rhesus monkeys, and humans metabolize BPA at similar rates, raising the possibility that effects observed in animal models may be relevant to humans as well. vom Saal is a Curator’s Professor of biology at the University of Missouri. Visit the podcast webpage to download a full transcript of this podcast.

Brominated and chlorinated flame retardants are widely used in upholstered furniture and foam products. These compounds have been found to accumulate in the bodies of humans, and although more information is needed on health effects, the available toxicity data are troubling. In this podcast, Åke Bergman discusses the San Antonio Statement on Brominated and Chlorinated Flame Retardants, drafted in September 2010, in which an international group of scientists calls for greater awareness of and responsibility for this group of chemicals, including better life-cycle management. Bergman is a professor of environmental chemistry at Stockholm University in Sweden. Visit the podcast webpage to download a full transcript of this podcast.

Attention deficit/hyperactivity disorder, or ADHD, is one of the most frequently diagnosed neurobehavioral problems in children and is thought to be largely hereditary. But only a small number of cases have been linked to specific genes, leading many researchers to explore the impact of environmental exposures. In this podcast, Susan Schantz discusses how the neurologic effects of lead and polychlorinated biphenyls compare with symptoms of ADHD and what environmental health researchers can learn from those similarities and differences. Schantz is a professor of veterinary biosciences at the University of Illinois at Urbana–Champaign. Visit the podcast webpage to download a full transcript of this podcast.

Chlorine is one of the most common disinfectants used to kill microbes in water and make it safe for humans to swim in and drink. But when chlorine and other disinfectants combine with organic matter in pools such as sweat, urine, and skin cells, the results are disinfection by-products (DBPs), which have been linked with adverse health effects in animals and humans. In this podcast, Manolis Kogevinas discusses recent research on the carcinogenic and genotoxic potential of DBPs, but he also explains why people don't necessarily need to stop swimming in pools. Kogevinas is a professor and co-director of the Centre for Research in Environmental Epidemiology in Barcelona, Spain. Visit the podcast webpage to download a full transcript of this podcast.

In the past several decades there has been a sharp increase in the amount of artificial dyes and flavorings children encounter daily in foods, beverages, medicines, and toiletries such as toothpaste. Over the same period there has been a marked increase in the number of diagnoses of neurobehavioral disorders such as attention deficit/hyperactivity disorder. Bernard Weiss began studying potential links between artificial food dyes and neurobehavioral effects in children in the late 1970s. In this podcast he discusses some of his earliest research and tells why he remains convinced the two are connected. Weiss is a professor in the Department of Environmental Medicine at the University of Rochester Medical Center. Visit the podcast webpage to download a full transcript of this podcast.

The collapse of the World Trade Center buildings on 11 September 2001 created a massive cloud of dust that blanketed lower Manhattan and parts of Brooklyn. That dust comprised a complex mixture of building materials, office equipment, jet fuel, and combustion by-products. In this podcast, Paul Lioy discusses how this dust differs from other particulate matter and how these differences may have affected the health of those who were exposed to the dust. Lioy is the deputy director of the Environmental and Occupational Health Sciences Institute at the Robert Wood Johnson Medical School and Rutgers University. He is also the author of the book Dust: The Inside Story of Its Role in the September 11th Aftermath. Visit the podcast webpage to download a full transcript of this podcast.

As many as 70,000 volunteers and rescue workers responded to the 11 September 2001 World Trade Center (WTC) attacks, many toiling for months to clear mountains of debris containing a range of toxic compounds. Health effects seen since that time in WTC responders include respiratory, gastrointestinal, chemosensory, and mental health problems; many of these effects have persisted for years. In this podcast, Philip Landrigan discusses his work with WTC responders as a physician and an epidemiologist and how lessons learned from the WTC cleanup may be applied to other disasters. Landrigan is the chair of the Department of Preventive Medicine and dean for Global Health at Mount Sinai School of Medicine in New York. Visit the podcast webpage to download a full transcript of this podcast.

Although dispersants have been used to help clean up oil spills since the 1960s, it wasn't until the Deepwater Horizon disaster in the Gulf of Mexico that these chemicals made their way into the public consciousness. Use of dispersants always involves an environmental tradeoff, but the Deepwater Horizon situation presents special considerations because the chemicals are being used a mile underwater for the first time ever. In this podcast, Dana Wetzel discusses the dispersants used in the Deepwater Horizon spill and research needs regarding how these chemicals may affect aquatic species. Wetzel is a senior scientist and program manager at the Mote Marine Laboratory in Sarasota, Florida. Visit the podcast webpage to download a full transcript of this podcast.

Exposure to certain chemicals or stressors in utero can cause immediate health effects for fetuses and babies including lowered birth weight, birth defects, and impaired neurodevelopment. New lines of research are now showing that prenatal exposures may also contribute to health problems that typically arise later in life—such as obesity, diabetes, cardiovascular disease, cancer, and Parkinson disease—via changes to DNA transcription and the hypothalamic–pituitary–adrenal axis. In this podcast, Deborah Cory-Slechta discusses the phenomenon known as the fetal basis of adult disease. Cory-Slechta is a professor of environmental medicine at the University of Rochester School of Medicine and Dentistry. Visit the podcast webpage to download a full transcript of this podcast.

In the United States more than 40,000 women die of breast cancer each year, and almost 200,000 women develop the disease. Although survival rates have improved and risk factors have been identified, the causes of breast cancer remain unclear. In 2004 researchers at the National Institute of Environmental Health Sciences (NIEHS) began recruiting sisters of breast cancer patients for a study to explore environmental and genetic factors behind this disease. Now that more than 50,000 women have been recruited, Dale Sandler discusses what comes next for the Sister Study. Sandler is the principal investigator of the Sister Study and chief of the Epidemiology Branch at the NIEHS. Visit the podcast webpage to download a full transcript of this podcast.

Flame retardants known as polybrominated diphenyl ethers (PBDEs) are added to products such as furniture, car seats, textiles, and electronics. These chemicals improve safety by giving consumers more time to react if a fire breaks out. But now they are also showing up in the food we eat, the dust in our houses, and the bodies of possibly the entire U.S. population; meanwhile, recent evidence suggests the potential for worrisome neurodevelopmental effects. In this podcast, Heather Stapleton discusses what we know about routes of PBDE exposure and how these exposures may affect human health. Stapleton is an assistant professor of environmental chemistry at the Nicholas School of the Environment at Duke University and coauthor of "Metabolism of Polybrominated Diphenyl Ethers (PBDEs) by Human Hepatocytes in Vitro." Visit the podcast webpage to download a full transcript of this podcast. 7KbQa51d9Suzkb8B384c 7KbQa51d9Suzkb8B384c

In the 1950s biologists began noticing unusual behavior and various reproductive health problems in wild animals. Environmental health analyst Theo Colborn was one of the first to start asking what those trends might mean for humans. In this podcast marking the 40th anniversary of Earth Day, Colborn discusses her research on the endocrine-disrupting effects of chemicals in the Great Lakes ecosystem—research that broke new ground in the field of environmental toxicology. Colborn, co-author of Our Stolen Future, now heads The Endocrine Disruption Exchange in Paonia, Colorado, and is a professor emeritus at the University of Florida in Gainesville. Visit the podcast webpage to download a full transcript of this podcast. 

Every year about 2,000 new chemicals are submitted to the U.S. Environmental Protection Agency (EPA) for safety approval. Figuring out how a chemical might affect human health involves lab studies that can cost millions of dollars and take years to complete. Now a team of researchers at the EPA is working on a way to make the safety testing process more efficient and less expensive. In this podcast, Robert Kavlock describes the EPA ToxCast™ project, which uses existing toxicity knowledge as a blueprint for broad-scale chemical assessment. Kavlock is director of the EPA National Center for Computational Toxicology and coauthor of "In Vitro Screening of Environmental Chemicals for Targeted Testing Prioritization: The ToxCast Project." Visit the podcast webpage to download a full transcript of this podcast. 

An estimated 1-1.5 million Americans live with autism, a neural disorder characterized by impaired social interaction and communication. Some research suggests environmental factors play a role in autism, while other findings point to a genetic basis. More recently there's been a heated public debate about whether autism is caused by the mercury in vaccines commonly given to children. In this podcast, Irva Hertz-Picciotto discusses the implications of research comparing blood mercury levels of autistic children with those of typically developing children. Hertz-Picciotto is an environmental epidemiologist with the Medical Investigation of Neurodevelopmental Disorders (MIND) Institute at the University of California, Davis, and the first author of "Blood Mercury Concentrations in CHARGE Study Children with and without Autism." Visit the podcast webpage to download a full transcript of this podcast. 

DDT is unique among the "dirty dozen" compounds banned under the Stockholm Convention on Persistent Organic Pollutants because specific exceptions are made for the indoor spraying of this pesticide to control the mosquitoes that spread malaria. DDT is a cheap, effective weapon against the spread of this disease, which infects nearly 250 million people each year and kills nearly 1 million. However, little is known about the long-term human health effects of exposure to DDT in the context of indoor spraying. In this podcast, Brenda Eskenazi describes research issues surrounding the use of DDT to control disease vectors. Eskenazi is a member of the DDT Expert Group of the Stockholm Convention, and is the Maxwell Professor of Maternal and Child Health and Epidemiology and director of the Center for Children's Environmental Health Research at the University of California, Berkeley. She also is the first author of "The Pine River Statement: Human Health Consequences of DDT Use." Visit the podcast webpage to download a full transcript of this podcast. 

Industrial-scale farms known as concentrated animal feeding operations (CAFOs) have become an increasing focal point for environmental health research because of their emissions and concerns they may contribute to antibiotic resistance, adverse community impacts, and zoonotic disease outbreaks. They are also a source of political controversy in states including North Carolina and Missouri where government agencies are grappling with decisions about CAFO monitoring and permitting. In this podcast, Peter Thorne describes some of the health concerns surrounding these facilities. Thorne, director of the NIEHS-funded Environmental Health Sciences Research Center at the University of Iowa, is the lead author of an EHP mini-monograph on environmental health effects of CAFOs. Visit the podcast webpage to download a full transcript of this podcast. 

A number of recent studies have reported finding measurable levels of persistent organic pollutants in human milk, and many daily activities expose nursing women to toxic chemicals that can end up in their milk. Although many of these chemicals can cause adverse health effects in humans, studies consistently conclude that, overall, the benefits of breastfeeding outweigh the potential toxicity threats posed to nursing children. In this podcast, Lynn R. Goldman discusses why breastfeeding is still the optimal method of infant feeding despite the presence of pollutants in human milk, and describes precautions that mothers can take to protect their milk. Goldman is a principal investigator for the Johns Hopkins University Center for the National Children's Study and a coauthor of "Global screening of human cord blood proteomes for biomarkers of toxic exposure and effect." Visit the podcast webpage to download the full transcript of this podcast.

Heat waves kill more people in the United States each year than any other natural hazard, and many regions worldwide are experiencing more frequent and more severe heat waves. But not all people and not all places have the same vulnerability to heat-related health effects. Identifying those who are more vulnerable will be critical to effective public health interventions. In this podcast, Colleen Reid discusses an innovative method for mapping the sections of urban areas across the United States where residents are more likely to suffer heat-related health effects. Reid is the lead author of "Mapping Community Determinants of Heat Vulnerability" and a PhD candidate at the University of California, Berkeley. Visit the podcast webpage to download a full transcript of this podcast. 

The many adverse health effects caused by chronic arsenic exposure are a concern for the hundreds of millions of people worldwide whose drinking water contains elevated levels of this naturally occurring element. A new rodent study suggests arsenic may also contribute to immune suppression. In this podcast, Josh Hamilton describes the potential implications of this finding for human health, including the possibility that arsenic exposure could help explain why certain populations have been hit harder by pandemic novel H1N1 flu. Hamilton is the senior author of "Low-Dose Arsenic Compromises the Immune Response to Influenza A Infection in vivo" and a senior scientist at the Bay Paul Center for Comparative Molecular Biology and Evolution, part of the Marine Biological Laboratory in Woods Hole, Massachusetts. Visit the podcast webpage to download a full transcript of this podcast.