by Nancy Maddox, MPH, writer
Hoosick Falls (population 3,600) is a rural river-bend village in upstate New York, about five miles from Vermont. Norman Rockwell and Grandma Moses both lived nearby, in a landscape adorned with rolling hills and the flowing waters of the Walloom and Hoosic rivers. Once upon a time, children flew down snowy village slopes on cast-off sheets of TeflonTM from the old, local Honeywell plant, according to the New York Times.
But that was years ago. Long before Michael Hickey’s father died of kidney cancer in 2013. Before Hickey tested his widowed mother’s tap water for the perfluorinated compounds (PFCs) once used to make TeflonTM here. Before the test results came back positive, with levels of perfluorooctanoic acid (PFOA) spiked above the US Environmental Protection Agency’s (EPA’s) “health advisory level” for drinking water—now set at 70 parts per trillion (ppt) PFOA and perfluorooctane sulfonate (PFOS) combined.
From that point onward, the feel of village life changed. Wadsworth Center Laboratories confirmed that Hoosick Falls’ public water supply, serviced by an underground aquifer, was laced with about 600 ppt PFOA. The state department of health provided residents with bottled water for drinking and cooking and made plans for water treatment. And an EPA administrator wrote the village mayor, noting PFOA’s “extreme persistence in the environment and its toxicity, mobility and bioaccumulation potential.”
Yet, in the midst of this situation, Hoosick Falls was fortunate in one regard. Just 30 miles south in Albany, scientists at the Wadsworth Center, part of the New York State Department of Health (DOH), had been investigating PFCs for many years, looking at levels in wildlife and then newborn screening bloodspots. The scientists knew these emerging, unregulated compounds—associated in some studies with endocrine disruption, developmental problems, testicular cancer, kidney cancer, liver damage and thyroid disease—had raised concerns in other states. And they recognized the value of being able to measure the chemicals in people—part of the science of biomonitoring.
“If it’s in the water, and we’ve been drinking it, are we exposed?”
An important early biomonitoring success story occurred in the late 1970s, when the US Centers for Disease Control and Prevention’s (CDC’s) second National Health and Nutrition Examination Survey (NHANES II)—the only US health survey incorporating laboratory testing on blood and urine—included lead testing for the first time. James Pirkle, MD, PhD, director of the Division of Laboratory Sciences (DLS) in CDC’s National Center for Environmental Health (NCEH) said NHANES II “showed, unexpectedly, that gasoline lead was a major exposure for children and for adults—a huge finding that we would not have known otherwise.” Soon thereafter, the country began phasing lead out of gasoline.
Today, NHANES tests a nationally representative slice of the population (about 5,000 people/year) for over 300 chemicals, providing critical baseline or “background” levels of exposure for US residents overall. But state biomonitoring efforts to document local background levels and to test for suspected elevated exposures have been little funded and lagging (as have efforts to track health outcomes associated with elevated exposures to determine high-risk exposure levels).
“Is every state prepared for biomonitoring emergency response?” asked Lovisa Romanoff, MS, deputy director of laboratory sciences at NCEH. “I would say it depends on what chemical we’re talking about. Lead, probably yes. PFOA, no. There are not that many labs that measure chemicals like PFOA.”
National health authorities and public health laboratory leaders would like to see this change. Said Pirkle, “It remains a main priority for me to help expand state biomonitoring programs.”
One step toward that goal is the November 2017 launch of the APHL/CDC National Biomonitoring Network (NBN), envisioned as a collaboration of biomonitoring laboratories with harmonized test methods and quality management systems that yield comparable data, accuracy and precision.
Although the network has yet to formally accept laboratory members, it is already seen as a resource to help laboratories plan studies across state lines, exchange lessons learned and access subject matter expertise. So far, the network has workgroups focused on study design, laboratory methods, and the revision and expansion of APHL’s 2012 Guidance for Laboratory Biomonitoring Programs.
Ultimately, said Pirkle, the NBN will provide “better opportunities for better science.” Ken Aldous, PhD, co-chair of the NBN Network Steering Committee and director emeritus of Wadsworth’s environmental health sciences program, said as soon as Hoosick Falls residents learned about the village’s tainted tap water, they had the exact kinds of questions biomonitoring is designed to answer: “Are we contaminated [with PFOA]? … If it’s in the water, and we’ve been drinking it, are we exposed?”
New York State offered to test everyone in the village and outlying area. And Aldous secured CDC approval to utilize Wadsworth’s high-tech, CDC-funded, public health emergency preparedness laboratory, part of a nationwide network of surge capacity labs, collectively known as the Laboratory Response Network for Chemical Threats (LRN-C).
Wadsworth scientists immediately set about devising a high-throughput method to measure PFOA in blood, using liquid chromatography/tandem mass spectrometry with 96-well plate sample prep. Over the following months, the NYS DOH collected specimens from about 2,900 people. Unsurprisingly, given the US background exposure documented by NHANES, almost all tested positive for the compound. More concerning, the geometric mean level for specimens from people served by village water was significantly above national background levels.
Yet Hoosick Falls was not an isolated incident. Elevated levels of PFOA were confirmed in the water supply of nearby Petersburgh, NY ( about 90 ppt), and in private well water in North Bennington, VT (up to 2,880 ppt), both incidents associated with local manufacturing plants. And another PFC, PFOS (present in the foams used to suppress aircraft fires), was detected in:
- Lake Washington, the water source for Newburgh, NY (about 150 ppt). (Nearby Stewart Air National Guard Base has since been declared a Superfund site, with PFOS levels as high as 5,900 ppt.)
- Well water supplying New Hampshire’s Pease International Tradeport, the site of the former Pease Air Force Base.
Because Vermont and New Hampshire had no capability to test for PFCs in human tissues at the time, Wadsworth took on the bulk of the biomonitoring for all of these incidents, ultimately testing about 7,500 specimens, so far.
Community Outreach Key to Biomonitoring
All of those interviewed for this article agree that the need for biomonitoring is likely to grow, as the extent of existing environmental health threats becomes better understood and new threats arise.
Already, companies like DuPont are using a new compound, GenX, in place of the PFOA they once used to make TeflonTM, stain-resistant carpeting and other household products. The problem is, the limited data thus far available suggest GenX is associated with some of the same health problems as PFOA, including cancer.
Yet despite the multiplying threats, funding for biomonitoring remains scarce.
Perhaps the biggest booster has been CDC, which has funded state biomonitoring efforts since 2001, when the agency awarded planning grants to 25 state and regional programs, supporting 33 states in all. “The purpose of those awards was to task states with developing plans for what they would do with larger implementation grants,” said Romanoff. But after 9/11, the follow-up funding never made it through Congress. Instead, CDC cobbled together some of its own core revenue to compete just three new awards, running from 2003-2007.
“These were smaller awards,” said Romanoff. “The mass spectrometry [biomonitoring] platform is incredibly expensive We were just not able to do what we really hoped for.”
Then, in 2009, with dedicated funding for state biomonitoring, CDC competitively awarded California, New York and Washington full implementation grants, totaling $5 million/year for five years. And the agency currently supports nine states with six awards.
One of those programs is based at the New Hampshire Public Health Laboratories, where scientists are examining levels of arsenic and uranium in 500 private well water users, their well water and a comparison group of 50 public water users.
New Hampshire’s groundwater is known to be at risk for elevated arsenic, owing to two sources of the heavy metal: New England’s granite bedrock geology and past use of arsenic-laced pesticides on local orchards and farmland. Only Maine has a higher rate of bladder cancer than New Hampshire and, in both states, it is linked to arsenic exposure. Uranium was added to the study based on past research showing that it tends to co-occur with arsenic.
One of the most interesting aspects of the New Hampshire study is the public health laboratory’s outreach to recruit participants. Amanda Cosser, MPH, the laboratory’s biomonitoring program manager, said “We identified towns we want to target based on groundwater arsenic risk modeling from the US Geological Survey and picked a random set of addresses with private wells. Then we introduce the project with a postcard that gives three ways to contact us: call, e-mail or complete an online survey. If they don’t respond, we follow up with a formal letter.”
Additional outreach comes through the involvement of town administrators, managers and selectmen. After meeting with laboratory staff, said Cosser, “they’ve taken it upon themselves to advertise our study in their town letters and on their websites.”
So far, 375 well water users have joined the study.
Another CDC-funded study is underway at the Virginia Division of Consolidated Laboratory Services (DCLS), under the direction of Chris Retarides, PhD, and Shane Wyatt, the lab’s lead biomonitoring scientists. The focus here is two-part: (1) a surveillance survey to determine baseline, local exposures to six heavy metals and perchlorate (a naturally occurring contaminant in fertilizer and a rocket fuel constituent, linked to thyroid disease) and (2) an assessment of firefighter’s exposure to toxic combustion products, including polycyclic aromatic hydrocarbons (PAHs) produced by burning wood and cyanide produced by burning plastics.
“If we see high levels of PAHs and very low levels of cyanide, we know the exposure was mostly dermal,” said Retarides, since PAHs can be absorbed through the skin or inhaled, while cyanide is largely inhaled.
As in New Hampshire, community outreach is a key study component. Retarides said the researchers initially considered working through local health departments to enlist surveillance survey participants, but found health department staff to be taxed with other important duties. Instead, they chose to recruit participants at the Commonwealth’s 23 community colleges, knowing that most recruits would be under Virginia’s median age of 37.
Said Retarides, “It says on the Virginia Community College System webpage that, no matter where you are in the state, you’re no more than 30 minutes from a community college. ... These are commuter schools; people go there because they’re convenient. And most [community college students] are exposed to the local environment and water systems.”
As of late September, the DCLS team had collected over 900 urine specimens for the surveillance survey and completed analyses on about 500, with no unusual findings thus far. The firefighter study is still ramping up.
A New Frontier: The Exposome
Retarides has high hopes for NBN, which he called “a great undertaking.” Having been on the periphery of efforts to establish the network, he said, “I know the people involved are a great treasure trove of knowledge. It will be a big help to states looking for survey methods, analytical methods and epidemiology and analytical chemistry expertise. [Biomonitoring] is not just about measuring samples, you have to go out and get them, and the measurements have to be meaningful.”
In addition to providing information and training, network members could also perform testing for other laboratories within or outside NBN, either as part of an emergency response or to support a biomonitoring study. Aldous said, “It’s not just routine testing, but testing for novel compounds that can be disseminated across the network, maybe something in commerce now that people aren’t taking great notice of, but that needs to be looked at across the country.”
Julianne Nassif, MS, director of APHL’s Environmental Health program, said NBN will focus initially on developing technical guidance for biomonitoring programs, a membership application process and a network structure, with tiers based on a laboratory’s capability and activities.
NBN leaders also plan to convene additional workgroups, to begin an initiative on quality management and quality systems, and to investigate options for where to store state biomonitoring data, such as in the EPHT Network maintained by CDC or a new, stand-alone database.
In the meantime, the science of biomonitoring continues to evolve in ways big and small. The latest buzz word in the field is exposome, encompassing the entire universe of one’s environmental exposures from the prenatal period onward, together with all the associated biological responses to those exposures throughout the lifespan. Thanks to technological advances, particularly in digital electronics, scientists expect to measure more and more exposome analytes in ever tinier specimens.
But it’s not just scientists who are concerned with biomonitoring these days. Doug Farquhar, JD, who monitors environmental health legislation at the National Conference of State Legislatures, said the topic increasingly arises in state law: “[Historically] if I saw a couple [biomonitoring-related] bills it would stand out. This year, it’s like wham! We had four states include a biomonitoring effort in their state’s appropriation [MA, MN, NH, NJ,] and another six with legislation including a biomonitoring component.”
Back in New York, Aldous cited one reason biomonitoring should be of interest to policymakers: program evaluation. For example, since a new water-treatment plant filtration system was installed in Hoosick Falls, water going out through the public distribution system has measured less than 2 ppt PFOA. Given the compound’s three-year half-life in the human body, residents’ body burden should be dropping.
A biomonitoring study to confirm that assumption, Aldous said, “would show the value of the remediation, the effort put in and the money spent to reduce the exposure.”
Biomonitoring may not yet be a household word, but the concept is gaining currency, with consumers seeking out products like paraben-free make-up, BPA-free water bottles and phthalate-free pacifiers.
“People want to know more about what’s in their bodies, “ said Kristin Dortch, MS, CDC’s biomonitoring project officer. “If they know another state tested for [a high-profile chemical], they want to know, Why not us?”