After two UNLV researchers discovered asbestos in Southern Nevada soil, they wanted to study it further. Why did state health authorities stand in their way?
Sitting in her small, cluttered office on the fourth floor of UNLV’s Science and Engineering Building, geology professor Brenda Buck pauses to ponder my question: Has her recent discovery of naturally occurring asbestos in the Boulder City area had any personal — emotional, maybe — impact on her? The sun shines through a north-facing window, lighting up her strawberry-blond hair and blue eyes.
“Yes,” she finally says. “I used to board my horse, Jimmy, at a stable in Boulder City. Sometimes, when my grandkids were little, I’d take them for rides out there. I can’t remember specifically where we’d go or whether it was windy, which would have increased their chance of exposure (to any asbestos in the air), but I do think about that now.”
A few weeks later, from his Carson City office at the Nevada Division of Public and Behavioral Health, Ihsan Azzam says almost exactly the opposite, without the slightest hesitation: “I would move to Boulder City in a heartbeat,” he says. “I would be happy to live there with my kids and grandkids. I would not be worried about the risk at all.”
As the state epidemiologist, Azzam says, it’s his responsibility to make sure Nevadans are safe. Sounding every bit as sincere over the phone as Buck appeared in person, he repeats several times that he is convinced her discovery is no cause for alarm, that the existence of asbestos in the environment alone does not equal an impending public health crisis.
How are we to know who’s right?
Buck has recently been on a public speaking tour of sorts, appearing in community forums and academic gatherings to present the findings she and fellow UNLV geology professor Rodney Metcalf have gleaned from nearly five years of collecting and testing soil samples in Southern Nevada — findings that were published in an academic paper in January. At a December luncheon hosted by fundraising nonprofit Nevada Biotechnology & Health Science, I witnessed the impact of her presentation firsthand.
“This is blowing me away,” a middle-aged woman in the audience said. “Let’s say you were able to do all this further study and you find that there is a high concentration of asbestos in the air. You’re going to be fighting a lot of different people to get anything done about it. It’s very difficult to change the (political) environment.”
The “further study” that the shaken spectator was alluding to is the crux of the real question at hand: Does Buck and Metcalf’s work merit continued examination — and funding — and if so, then why did the state health department bar them two years ago from accessing patient data critical to their work? Or are they, as Azzam’s stance suggests, barking up the wrong tree, looking for a danger that simply isn’t there?
It’s not just a philosophical problem. If citizens are, indeed, inhaling a harmful amount of asbestos fibers and the state knowingly ignores it, then there could be long-term health implications that add up to expensive lawsuits — not to mention ruined lives. If, on the other hand, there’s nothing in the air around Boulder City worth worrying about, the spotlight on asbestos could create an unnecessary stigma, stunting economic development projects such as the I-11 freeway. In Buck’s view, her preliminary findings are compelling and deserve a public airing; to the state — which controls the health data — her team has violated good-faith research protocols.
What’s in a fiber?
The phrase “naturally occurring asbestos” is redundant, says National Institutes of Health toxicologist Christopher Weis, who worked on the high-profile environmental disaster in Libby, Montana, site of a vermiculite mine that sickened many of the townspeople. In fact, all asbestos is naturally occurring, because “asbestos” is the generic term for a variety of mineral particles that are elongated. (Under a microscope, they look like hairs.) Because “asbestos” came to be associated with its industrial applications — in home insulation, for instance — scientists took to distinguishing its natural and processed forms. Apart from “naturally occurring asbestos,” they will use terms such as “fibrous minerals” and “asbestos-like minerals” to be clear that they’re talking about the stuff that’s coming out of the Earth, not out of a factory.
The distinction also has political undertones. Asbestos, both in nature and in manufacturing, has been the subject of intense controversy. There are approximately 400 types of fibrous minerals, but only six of them are regulated. The small number is probably due to their broad industrial application; these tiny particles have a handy ability to resist both heat and chemical degradation. They also have the ability to wreak havoc on the human body.
“When they’re breathed in, they can find their way down deep into the lung, to the place where oxygen is exchanged with carbon dioxide, the alveoli,” Weis says. “Because of that, and their being made out of rock, the lung has a difficult time removing them. They’re too big to be efficiently removed by the alveoli, so they cause scarring. That part of the lung is extremely fragile, so that scar tissue no longer participates in gas exchange. It reduces the person’s ability to breathe. A couple particles is not a problem. A few, not a problem. But if you’re exposed to these materials every day, you can load your lung with enough of those particles to create a serious breathing problem. And once that scarring process starts, it progresses, even if you remove the exposure. Ultimately, it can lead to death.”
The inflammatory respiratory diseases resulting from this process are often lumped under the diagnosis “asbestosis,” which triggers an inflammatory chain reaction in the lung that can lead to debilitating disease whose symptoms are indistinguishable from COPD.
Diagnosing asbestosis is tricky. People move around, maybe living near an asbestos mine at one point in their lives and working in a factory that uses asbestos at another. Their health history may include both asbestos exposure and smoking, as well as other causes of respiratory diseases. Weeding out the exact cause of their ailment requires lengthy interviews and precise tools. Buck says she went to one of Las Vegas’ best pulmonologists for tests to determine whether she had asbestos in her lungs, and he lacked the scanning technology and interpretive expertise to tell her for sure.
So, if you’re a geologist who has stumbled on fibrous minerals in the soil, and you’re worried that they may be finding their way into people’s bodies, what do you do? You consult the public health record.
A difference over data
“The way you worry about fibrous minerals is, you first need to look at mesothelioma,” Buck says, near the beginning of her presentation, “because it can only be caused by exposure to fibrous minerals. It doesn’t matter if you smoke or not; it won’t make any difference to this particular disease, so this is a great disease to use to figure out if people are being exposed to fibrous minerals. Unfortunately, it’s fatal. Fortunately, it’s preventable; you just need to not be exposed to fibrous minerals.”
Mesothelioma is an aggressive form of lung cancer. It’s primarily an occupational disease, and it takes a long time after exposure to get sick, often 30 years or more. So, if you’re exposed at a typical working age of 30-50, you may not get sick until your 60s or later. The median age for diagnosis is 74. One other thing: It’s extremely rare. Only a couple Americans out of every 100,000 get it, according to the National Cancer Institute.
This, Buck says, means that mesothelioma caused by environmental exposure to asbestos sticks out. It occurs in the young, who haven’t lived long enough to be exposed at work and then have the disease take hold. It also occurs evenly among men and women, in contrast to occupational mesothelioma, which is more common in men.
So, she examined U.S. Center for Disease Control and Prevention’s mesothelioma figures for Nevada, looking for the tell-tale signs of incidence among the young and women. What she saw, she thought, called for a second opinion. Despite being a medical geologist, who specializes in minerals’ impact on human health, Buck lacked mesothelioma expertise. For that, she turned to Francine Baumann, an epidemiologist at the University of Hawaii’s Cancer Center whose specialties include identifying environmental clusters of malignant mesothelioma.
Baumann requested data from the Nevada health department’s cancer registry. Her analysis fell in line with Buck’s: a small number of cases of mesothelioma among young people (as young as 15 to 24) and a relatively low male-to-female ratio of incidence in Southern Nevada. She, Buck and Metcalf compiled their findings for a presentation at the 2012 conference of the Geological Society of America. The abstract’s title, “Potential Link Between Young Malignant Mesothelioma Cases and Environmental Exposure to Fibrous Carcinogenic Minerals Near Urban Areas of Southern Nevada,” backs up Buck and Metcalf’s description of it as preliminary, meant to be hashed out with their scientific peers. The GSA published the abstract on its conference website, and it caught the eye of journalist Leslie Harris O’Hanlon. Reporting on a story for the Journal of the National Cancer Institute, O’Hanlon interviewed not only Baumann, Buck and Metcalf, but also the health department’s Azzam.
He was not pleased. Looking back today, Azzam says, he was taken by surprise. Why would this researcher, who’d gotten data from his office, not bring a possibly serious public health issue to his attention, but instead offer it up for public discussion? He went to state biostatistician Jay Kvam, who’d provided the data to Baumann, and they did their own internal review. A disagreement over the meaning of the numbers is shown playing out in a series of ensuing emails between Azzam and O’Hanlon, and Baumann and O’Hanlon, with the reporter playing intermediary, conveying to each epidemiologist the other’s divergent point of view.
Baumann stuck to her argument that the numbers, while low, included sufficient incidence among the young and females to suggest non-industrial exposure.
“We disagree,” Kvam says. “We found the Nevada data to be on par with that of other states, or below it.”
Kvam, who readily fulfilled all of Desert Companion’s requests for statistics, insists that the problem with Baumann’s interpretation is the small sample size. “As you see,” he says, walking me through a customized search on the health department’s cancer data portal, “most years the number of cases of mesothelioma is zero. For example, in 2008, there were no deaths from mesothelioma. Does that mean it was eliminated in 2008? No, it’s just so uncommon that it didn’t occur that year. In 2009, someone died of mesothelioma. Does that mean that the rate of mesothelioma doubled? No. Any rate related to such a small number would be subject to variation. Really, that’s the takeaway: Very few people, an incredibly small number, are dying from this disease.”
Buck doesn’t dispute this. But she also doesn’t believe averaging the number of cases statewide and comparing that with other states’ averages is a useful measure of environmental exposure to asbestos as distinguished from industrial exposure. In Libby, Montana, she notes, there have only been a couple dozen cases of mesothelioma, yet it’s widely considered to be among the United States’ worst public-health catastrophes (and hundreds of other Libby residents were afflicted with asbestos-related diseases).
“We wouldn’t be stupid enough to say it was a 100 percent increase (from a year with 0 cases to a year with 1),” she says. “What we’re saying is, if there’s one 20-year-old person who has it, then why is that? If as many women as men have it, why? That suggests environmental exposure. It needs further exploration. And the fact that we did find asbestos in the environment intersects with that.”
Anyway, it became a moot point. On October 30, 2012, Nevada State Health Officer Tracey Green sent Baumann a cease and desist letter regarding the GSA conference abstract. It requested that Baumann not only retract the abstract, but also cease presenting or publishing her work based on the statistics the state gave her in any other forum. Although Green questions Baumann’s scientific conclusions, the basis she gives for the cease-and-desist is more straightforward: The researcher, in being granted access to the data, had signed an agreement including a clause that gives the state health department the right to examine and approve any resulting material proposed for publication, prior to publication.
“Despite having acknowledged this legal obligation, you chose to proceed with publishing your abstract to the GSA website without having first provided a copy to me or, to my knowledge, any other staff member at NSHD,” Green writes. In the letter’s conclusion, she says, “I’d like to take this opportunity to also inform you that your request for NCCR data of mesothelioma cases is disapproved and that no further data requests from you shall be considered.”
“To be honest, I was scared,” Metcalf says, looking back today at the moment he got a copy of the cease-and-desist from Baumann. He, Baumann and Buck scrambled to get the abstract removed from GSA’s website and retool their presentation to omit any of the forbidden data. They say they called and wrote to Green asking for further explanation, for a second chance, but got no answer. Baumann stopped working on the project. (She has since gone on to study the distribution of fibrous erionite, an asbestos mineral, in the U.S. and its implications for human health, funded by a U.S. Geological Society grant.) Buck and Metcalf regrouped. Then, they went underground, focusing on the geology so as not to attract the attention of, or further upset, the health department.
Using Metcalf’s expertise in predicting which types of minerals will be found where, they sketched a map of possible asbestos sites in the valley.
“We’ve sampled 43 sites so far — doing bedrock, soil, dust and clothing at each one. Every sample has had asbestos in it,” Buck says. “Pretty much, the model is holding up.” Once, she says, she even went straight to her lab after riding Jimmy for a couple hours and took samples from her clothing and shoes. They tested positive too. In her presentation, she shows slides of gravel and rock in an area that tested positive. The gravel lines Adams Boulevard in Boulder City, passing in front of Martha King Elementary School.
Yet, as Azzam is quick to remind, the presence of asbestos alone doesn’t equal human exposure. “Tell me where the air is clean,” he says. “Our air is full of biological and chemical agents. So, having these fibers, it’s fact. I can’t say that it’s not. What I can say is, not all hazardous materials in our air have to translate into negative health outcomes. For hundreds of years, people have lived here. … The only thing that has changed is, they discovered asbestos.”
Buck agrees that the key is the exposure, since risk is determined by exposure. And the route for asbestos exposure is the air. During construction of the Boulder City Bypass for U.S. route 93, she says, contractors collected ambient air samples at four stations for three months. “The average of those three months is nearly an order of magnitude higher than the EPA’s reference concentration for non-cancer diseases, and those months were unseasonably wet," says Buck. "That’s really disconcerting, based on what I know is in the soil, and it being open to the wind more.”
She believes it’s cause to look closer — measure how much asbestos people may be breathing, if any, in a variety of places and circumstances (dry, wet, windy, calm) and doing a variety of activities (walking, driving an ATV). She wants to give mesothelioma patients the kinds of lengthy questionnaires developed post-Libby that help pin down their exposure and help train local doctors to identify signs of asbestos-related illnesses. She wants the ability to access health records unfettered, so that she can publish papers establishing the validity of her work, a prerequisite to grant applications that could keep her lab open, staff paid and experiments running.
Azzam says he’s not stopping her.
“To be honest, it’s public data,” he says, of the cancer registry numbers that have been accessible online since the Nevada Health Statistics Portal went live in early 2014. “The portal is open to everybody. Anybody can jump in.”
When Buck hears this, she’s surprised and encouraged, but also skeptical. The statistics one can glean using the portal are not the same as raw data. On the portal, incidence of a disease that numbers between zero and 5 cases per 100,000 are suppressed as statistically insignificant, and it could be a patient privacy violation to identify particular cases in particular areas. Only someone going through research protocols could see such data.
The health department does show signs of softening its stance. Azzam says, “We are way ahead of other states in identifying the naturally occurring asbestos in our environment, thanks to the work of Dr. Buck and her colleagues. Now that we know about it, we can keep an eye on it.”
With or without their help, Buck is plowing ahead. She and Metcalf are working with the Bureau of Land Management on a study of asbestos on its lands in Southern Nevada, and the EPA is analyzing some of their soil samples for asbestos in both the Boulder City area and on BLM land.
“There’s so much other work I could be doing,” she says, “but I’m pretty much 100-percent focused on this now. I truly believe it’s an emerging health issue.”