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Divining the Secret of Deformed Roadkill

Judy Hoy has tracked genital malformations among Montana's roadkill for years. She's been reporting disturbing trends for years, but few are paying her heed.
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Hard as it is to be a voice in the wilderness, Judy Hoy has been sounding an alarm in southwestern Montana for more than 13 years.

For years she's been documenting, through autopsies, photos, articles and scientific papers, changes — mutations, really — she's observed in various ungulate species in the valley. In particular, she's seen malformed genitalia among male white-tailed deer.

Such observations are not unique. More and more scientists are documenting reproductive changes in male animals ranging from cricket frogs to polar bears. But the response from public health and governmental agencies has been underwhelming.

White-tailed deer came into Hoy's purview 30 years ago when her husband, Bob Hoy, began collecting road-killed deer as a warden with the Montana Fish, Wildlife and Parks Service, or FWP. Beginning in 1980, Judy Hoy, a former elementary school science teacher, used some of the roadkill to feed wildlife she nursed at her Bitterroot Wildlife Rehabilitation Center.

In 1996, the Hoys noticed something strange among the roadkill. "It started with Buck No. 9," Judy said. "We called him that because he was the ninth buck we had seen with malformed genitalia."

Of 54 male deer aged 3 months to 1 year they examined beginning in late 1996 through 1997, only about a third had what the couple, over decades of observation, had come to consider a normal scrotum in size and shape and the normal placement of genitals. Thirty had a scrotum that was misaligned, with one testes positioned in front of the other, one had no scrotum, one had misplaced organs, and nine had ectopic (positioned between the body wall and the skin) testes.

The next year, 25 of 49 males had anomalies in their genitals. Between 1998 and 2000, two-thirds of the bucks examined had abnormalities. Hoy took notes, kept data, shot photos and began calling Montana's FWP.

She tried to interest them, or wildlife scientists in the University of Montana's Wildlife Biology program, in further study. At first, FWP personnel and others seemed interested, but it wasn't long before Hoy felt the door close in her face.


A few different times she showed photos or deer carcasses to state officials or veterinarians, who she recalled would agree in her presence that what they were seeing were malformations, only to file a report that termed them "normal variations." In the case of one buck, pathologists at the Montana FWP wildlife research laboratory wrote in a response to Hoy that the cause was "vehicular impact." Hoy said the animal had been hit from the front and there was no damage to its hindquarters.

When the FWP discounted Hoy's findings, she sought out other experts in the field. In 2000, William Croft, a physician and veterinarian who works as a consultant in environmental toxicology, pathology and biochemistry, drove to Montana from his home in Wisconsin to examine Hoy's white-tailed deer.

He found, after viewing Hoy's records and photos, that eight of 10 dead deer "clearly demonstrated abnormal development" and found "a total of 70 abnormal male deer detected of the 114 bucks examined for 1996 and 1997." He also examined other mammals and birds for a lack of development in facial bones that causes an overbite of the lower jaw.

(Hoy is more concerned about these changes than genital malformations in the deer population because animals with severe underbite may not be able to consume enough while suckling or later in life when grazing to survive.)

Croft concluded: "These and other animals examined, observed and photographed by Judy Hoy clearly demonstrate abnormal development within the white-tailed deer, elk, bird, goat, and toad populations and represent serious health changes within the wildlife of the Bitterroot Valley of Stevensville, Montana." He had his report notarized and sent it to the Ravalli County commissioners, the local governing body.

Hoy kept at it. In 2001, the Journal of Environmental Biology published a study in which she and her husband, with Douglas Seba and Theodore H. Kerstetter, postulated that pesticide exposure was the cause of the abnormalities — although, as the paper noted, "no conclusions of cause and effect can be currently justified." Kerstetter was a Humboldt State University zoology professor who retired in the valley; he died in 2008. Seba is an independent marine scientist with extensive experience in air and water transport of organochlorine pesticides. He continues to present Hoy's ongoing findings at the annual International Symposium on Man and His Environment, where he has been a keynote speaker.


What Might Cause This?
As Hoy collected examples of mutated deer, she kept asking why this was happening. As her paper with Seba and Kerstetter demonstrates, she started learning about chemicals that affect the endocrine system, which is made up of the intricate and mysterious interplay of hormones, organs and tissues that regulate metabolism and a wide range of functions, including reproduction.

For example, that underbite she'd noted has been linked to hypothyroidism and disruption of the thyroid system, which is a part of the endocrine system.

She described examining different endocrine-disrupting compounds, like a detective at a murder scene, eliminating suspects until she met up with chlorothalonil, a broad-spectrum fungicide. It had been the go-to fungicide in 1994 when neighboring farmers in Idaho were fighting potato blight.

The government monitors pesticide use, and Hoy learned chlorothalonil (sold under the commercial names of Bravo, Echo and Daconil) had been applied on potato fields in heavy doses in 1994 and for several subsequent years. Many of the fields where it was used lie directly west of the valley across the Bitterroot Mountains.

In 2007, Hoy found a scientist, Diane Henshel of Indiana University, interested in conducting a study of air circulation pattern, which Hoy suspected might bring chlorothalonil wafting into the valley. Henshel studies environmental pollutants, particularly pollutants' effects on developing organisms. She visited Hoy and examined animals at the rehabilitation center and reviewed Hoy's data and photos.


In 2008, three of Henshel's graduate students completed a baseline risk assessment for the Bitterroot Valley through air modeling. They found pesticides used in Idaho — but not in the Bitterroot — have been found in the valley, including chlorothalonil. And they confirmed that a metabolite of the chemical is chemically akin to cyanide and is many times more toxic to the endocrine system than is chlorothalonil. The authors recommended sampling of more pesticides in air, water and soil and testing of xylene, a toxic chemical released from a surgical-products manufacturer in the county. They also suggested testing possible synergistic effects of multiple pesticides in use in the valley, commonly referred to as a "cocktail effect" of chemicals.

Henshel told local media at the time that chlorothalonil was not detected at high enough levels to cause the deformities Hoy was finding, although she did not discount what she saw at Hoy's rehabilitation center. "I think that the jaw deformities are indicative," Henshel said. "I think the gonadal deformities are more than indicative, and they indicate there's a problem. You just don't show up with these deformities.

"I think what their report says is there's a lot more that needs to be looked at, and it really should stop being ignored."

In April, chlorothalonil was included on a list of pesticides that will be studied by the U.S. Environmental Protection Agency in its Endocrine Disruptor Screening Program.

Meanwhile, studies have been emerging from around the globe that lent credence to Hoy's suspicions, if not her specific suspects. Congenital hypothyroidism was found in foals in Saskatchewan. Hermaphrodite polar bears have been found in Alaska, as well as deer with undescended testes. A small, endangered population of Florida panthers has abnormal sperm, low sperm density and undescended testicles.

What had first been detected in toads, fish and birds was showing up in mammals around the world. Gwynne Lyons and Elizabeth Salter-Green of Britain's CHEMTrust — an organization that focuses on the problems of manmade chemicals in the environment — brought much of the research together in a 2008 report, "Effects of Pollutants on the Reproductive Health of Male Vertebrate Wildlife — Males Under Threat."

Lyons used the term "gender bender" chemicals in a press release on the report, noting, "Affected species are widespread and include flounder in United Kingdom estuaries, cod in the North Sea, cane toads in Florida, peregrine falcons in Spain, and turtles from the Great Lakes in North America." Hoy's paper was included in this study.

EDCs have slowly come into the public consciousness starting in the 1960s with severe birth defects caused by the prescription drug thalidomide. A decade later, daughters of women who took the synthetic estrogen known as DES to counter miscarriages in the 1950s were found to have high rates of vaginal and uterine cancer, and other health problems, including a high incidence of autoimmune diseases.

Since the 1960s, hundreds of EDCs have been identified; few have been assayed beyond standard industry tests, but a growing body of scientific study is pointing arrows at them and puzzle pieces appear to be falling into place around the globe, including a rather large piece: the finding that genes can be altered chemically through epigenetic switches.

A Primer on EDCs
To understand how EDCs affect the body, one needs to know a little about the way hormones operate. DES and other man-made and natural compounds mimic natural estrogen and are able to essentially take the place of estrogen at receptors that send chemical messages throughout the reproductive system. Studies have shown that small disruptions to the system at the right time can cause lasting damage.

DDT, PCBs and dioxin are other known hormone-disrupting chemicals thajunet have reached the public consciousness. In recent years, other EDCs have been identified, including bisphenol-A (or BPA), which has been found to leach from polycarbonate plastic baby bottles and other containers, and Dow Chemical's 2,4-D, which was banned recently in Quebec province.

In 1996, Congress passed the Food Quality Protection Act, which called for the EPA to screen and test pesticide chemicals for possible endocrine disruption. But it has taken 13 years and a lawsuit from the Natural Resources Defense Council to get the ball rolling. In April, the EPA's screening committee released a list of 67 pesticides that will be the first tested in the program.

The Food Quality Protection Act requires the EPA to "provide testing of all pesticide chemicals." That could take awhile. There are about 80,000 chemicals in production today, and the majority of them are neither pesticides nor pharmaceuticals, according to NRDC staff scientist Sarah Jannsen. Also, there is no mandate to screen inert ingredients, such as phthalates, which have been identified as EDCs; bisphenol-A is another chemical not on the initial list.

Theo Colborn, co-author of a 1996 book about EDCs, Our Stolen Future, has gone on record in a Scientific Americanarticle opposing the EPA's testing protocol, calling it "insensitive, crude and narrowly limited." She wrote that scientists at the leading edge of the study of EDCs were not included in the screening program.

However, Janssen, who writes a blog for the NRDC and holds an M.D. and a doctorate in reproductive biology from the University of Illinois, doesn't entirely agree: "It's taken EPA this long to get this far, and we'd rather that they start with what they have and become more nimble in the future. I think it's important that they put in screening assays and testing that are more understanding of today's science. But we don't want them to scrap the whole program and start all over, because here we are $100 million and 12 years later and we still haven't tested a single chemical."

One of Colborn's main concerns as to how the testing will take place relates to what is called the low-dose hypothesis. Simply stated, the hypothesis is that "a broad selection of chemicals can interfere with the normal development of a baby at extremely low levels of exposure." This flies in the face of the creed toxicologists have gone by for decades, that the size of a dose likely determines deleterious effects — or "the dose makes the poison."

Many endocrinologists are joining Colborn in the call for low-dose testing. A study published in Environmental Health Perspectives in July referred to the dose-makes-the-poison hypothesis as "16th century dogma" (it's based on an observation of Paracelsus) and noted that it "conflicts directly with well-established principles in endocrinology regarding hormone action." The report, which was led by John Peterson Myers, CEO and chief scientist for Environmental Health Sciences, discusses several scientific studies that have shown high- and low-dose exposures of EDCs rendering unexpected outcomes, with low doses often affecting gene regulation.

The American Chemistry Council says low dose is a "hypothesis that remains to be proven," according to Richard Becker, senior toxicologist with the organization. (A link to his 2004 presentation on EDCs can be found here.) And so far, the EPA seems to agree. In 2002, the EPA released a statement that "additional research is needed to better understand the low-dose hypothesis" but that "it would be premature to require routine testing of substances for low-dose effects."

Becker said that the chemical industry has used a battery of tests designed to screen for adverse health effects during fetal development. He said studies that assay low-dose effects haven't resulted in a model that is reproducible.

Asked if he was concerned about potential health problems suggested by recent work, he cautioned about studies that "haven't used state-of-the-art standards of practice." He pointed to the World Health Organization for its synthesis of scientific papers on the subject and a site developed by the University of Ottawa as a clearinghouse on endocrine science.

The WHO registry includes a review and discussion of all studies published worldwide deemed scientifically worthy on a topic. The most recent discussion of EDCs by WHO was completed in 2002.

Janssen would disagree with Becker about the studies to date. She cites "hundreds of studies by independent academic scientists" that tie EDCs to human health problems.

"I think one of the other big problems happening at EPA is that they've been unwilling to regulate pesticides based on their endocrine disruptor effects," she said. "And I think they've kind of been hiding behind this smoke screen of the screening committee when we have information that would be reliable information for us to use."

In a recent interview on the "Living on Earth" radio program, Tracy Woodruff, who worked as an EPA scientist for 13 years and now directs the program on reproductive health and the environment at the University of California at San Francisco, concurred with Janssen's assessment.

Janssen was not familiar with Hoy's study or with the chemical chlorothalonil. Still, she said, "Wildlife are really the canaries in the coal mine for us because the things we're seeing in wildlife are impacting human health."

She said undescended testes and malformed genitals are two of the most common birth defects seen in baby boys in the U.S. A recent study links these birth anomalies to phthalate exposure. "We don't keep very good records here," she said, "but in Western European countries, they've seen a dramatic increase in these conditions in last 40 years. Why is it happening? We probably can't pinpoint one chemical. It's probably a combination of several chemicals. The hard part is going to be trying to find out how we're going to be able to reduce the incidence of this condition by eliminating chemical exposure. We'll probably never be able to go back and say, 'This was the one thing.'"

Focused on Chlorothalonil
Hoy grew up on a ranch and is quick to tout her experience with "critters." She wears jeans with a large belt buckle and her hair in tight ponytails. She and her husband are no-nonsense Montanans. Their living room centers around two recliners and a television set, with Judy's computer and files taking up a corner area next to a massive stone hearth. The dining room table is stacked with papers, books and studies.

Hoy is clearly on a mission, and conversation with her is largely one-sided. She has a lot to say and not a lot of finesse in saying it. She almost snorts when she refers to state FWP personnel who she said dismiss her photos and other evidence by saying, " 'Judy wants everything to be perfect.'"

Even her defenders note her tendency to alienate. Linda Dworak, a physician and veterinarian who lives in the valley, wrote a letter to the editor of a weekly newspaper in 1998: "Hoy is easy to discount. She lacks credentials of scientific training, she draws conclusions prematurely, she overstates findings, and her determined persistence results in a sometimes brash demeanor that makes her message difficult to absorb. But, whatever one might think of her methods, Hoy's concerns are valid."

More than a decade later Hoy's concerns may have found some traction. Reports and studies in the summer of 2009 verify a decline in ungulate populations in Montana. A story published in the area's newspaper, The Missoulian, reported steep declines in elk population in the Bitterroot Valley at the time this was being written (wolves were the FWP's prime suspects). A study by Montana State University researchers released in July showed poor nutrition and lower birth rates in elk populations in the greater ecosystem of Yellowstone Park. Researchers tied the problems to predation by wolves but also noted that elk living in the presence of wolves had lower levels of progesterone, a hormone necessary to maintain pregnancy.

Hoy's fervor to indict chlorothalonil and, more broadly, to bring attention to possible effects of EDCs has led her to write more and to publish in places unlikely to win her many academic allies, including an article that documented findings of prognathism (or underbite) in several species in the valley, including deer, elk horses, cattle and domestic sheep and goats, that appeared in Wise Traditions in Food, Farming and the Healing Arts, a project of the Weston A. Price Foundation. (Dr. Stephen Barrett, a retired psychiatrist who runs the Web site, lists the foundation as an organization he views with "considerable mistrust.")

Meanwhile, people in the Bitterroot Valley increasingly come to her with reports of abnormalities in many species, including boy babies. "They bring their goats, dogs, horses here," she said. "I ask them if they're ready to write a letter yet."

When her name comes up, two camps form — those who trust her observations, which she has learned to present in scientific parameters, often with the help of scientists, and those who call her names and mistrust her findings.

A local taxidermist with 17 years in the Bitterroot, Gary Haas, recounted a hunting trip he was on with a longtime hunting partner. The man, who had worked for the FWP, was surprised to learn Haas was working with Hoy. "'She's a nut. She has no formal education,'" he recalled him saying. "I told him, 'Guess what? You don't need a formal education to see that something's wrong.'"

All along, Hoy has tried to get the FWP to agree that her observations represent a problem worthy of study. If it did, it would be easier to secure money for a study of deer populations in the valley. But the department remains unconvinced.

In 2004, the FWP released a second report in response to Hoy's ongoing advocacy, this time acknowledging a growing body of literature that ties exposure of certain chemicals to endocrine-disrupting processes. That victory was tempered as it maintained that the only clear malformation of white-tailed deer reported by Hoy up to that time were two deer with undescended testicles.

Not on the Evidence We've Seen So far
In a recent interview, Neil Anderson, the wildlife laboratory supervisor for the FWP, portrayed Hoy as a "passionate person" who tends to "see malformations" wherever she looks. He said populations of deer in the valley are normal, and FWP rangers are not finding anomalies.

Anderson said there is a need for clear data supporting a cause and effect before the agency would act. "She may be on to something," Anderson said. "But I don't have a way of proposing a study that would cost multimillions of dollars on the evidence we've seen."

When asked if he had kept up-to-date on studies on endocrine disruptors since he wrote the 2004 report, he said he had, but cautioned that findings in studies are not always what they appear to be. He referred to a paper in Environmental Science and Technology that postulated that organohalogen pollutants may reduce the size of sexual organs in both male and female polar bears in East Greenland.

"You have to be very critical of every study and how the data was collected," Anderson said. He criticized the polar bear study because there was "no discussion of the influence of age on the model or the findings." Nonetheless, a table in the paper provides the age of each bear studied, and the discussion breaks the ages down into adult and sub-adult and effects of chemicals on each group.

The free Web site uses mathematic algorithms and publication data to rank scholarly journals. A publication's "Eigenfactor" score measures its relative importance to the scientific community based on the journal's size and publication frequency, while its "article influence" score uses citation records to gauge the average influence one of the journal's articles in the first five years after publication. The top 1,000 scholarly journals have Eigenfactor scores between 0.01 and 1.99; the average article influence score for the journals in their database is 1.

The journal Environmental Science and Technology, which published the paper on Greenlandic polar bears, had an Eigenfactor score of 0.17 and an article influence score of 1.4. (The Journal of Environmental Biology, which published Hoy's paper, on the other hand, has an Eigenfactor of 0.001 and an article influence score of 0.088.)

While FWP is not convinced a study is needed, other people and groups have called for one. In 2002, a local group established through the U.S. Fish and Wildlife Service's Lee Metcalf National Wildlife Refuge, which is located in the valley, reviewed Hoy's findings. Members of the group included Dworak (the writer of the letter to the editor previously mentioned), William Hadlow, a nationally known veterinary epidemiologist, Donald Maclean, a physician with the Ravalli County Board of Public Health, Judy Smith, a physician with a background in molecular biology and public health, and Kerstetter. They recommended that "an investigation begin as soon as possible to evaluate the health of the white-tailed deer population in the Bitterroot Valley."

Nothing came of that, but Hoy kept at it. When Bob Hoy retired from the FWP in 2000, roadkill was not as easily available to her for autopsies. In the mid-2000s, FWP enacted a policy that required all motherless fawns be killed, and she was no longer able to rehabilitate young deer orphaned through roadkill, making another source of empirical data not easily available. So she found a way to keep recording data by examining roadkill where it fell and examining fawns rescued by neighbors.

Her latest numbers — for 2006 through June 2009 — show only six of 33 male fawns examined had bilateral scrotums; 26 had the left testes positioned in front of the right, and one had no scrotum formed. She has also continued to find malformed facial structure across several species, usually an underbite.

Haas, the taxidermist, has seen the incidence of prognathism in white-tail deer increase noticeably in recent years. He said he has talked with several traditional taxidermists (he uses an alternative approach, enlisting flesh-eating beetles to clean bones and skulls) who are "having a difficult time trying to mount these animals because they have a short lower lip — what they call a parrot lip. Many of them can't really close their mouths."

Haas, who has a degree in wildlife biology, is turning over his data on this "malocclusion" to Hoy for a study she is working on.

"I've seen what she's talking about — orientation of testicles on bucks and the changes in the jaws. I can't deny that there's something out there. There's something wrong."

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