This blog post is part of a biomonitoring series.
Dr. Carin Huset began her career measuring chemicals in water, not people. “My doctoral thesis was on PFCs in wastewater, rivers and landfills,” she said. “It was all environmental, not public health, and much more abstract.”
Huset now spends her time testing people for chemical exposure. This work, known as biomonitoring, is on the leading edge of public health laboratory science. Huset and other laboratorians at the Minnesota Department of Health (MDH) public health laboratory are able to measure the amount of natural and manufactured chemicals inside of a person by analyzing blood or urine.
Currently, Huset and partners in the local health community are working with a group of Native American volunteers from the Fond du Lac Band of Lake Superior Chippewa to measure the chemical levels in their bodies. People living in this community may have greater contact with environmental chemicals as consumers of traditional foods such as fish and waterfowl.
This biomonitoring project is part of the wider federal Great Lakes Restoration Initiative (GLRI), which is focused on cleaning up toxins, resisting invasive species, protecting watersheds from polluted run-off and restoring wetlands. The GLRI is funding the MDH’s work with members of the Chippewa tribe to determine the impact of pollution on the local population.
Since biomonitoring is a relatively new area of laboratory science, Huset and her partners began designing a study that had no real counterpart, and therefore had to overcome a series of mundane, but critical, difficulties. Minnesota staff needed to work out tricky legal agreements with partner labs, add a new testing capability, identify and interview the study’s participants, and train clinic and other external staff.
“We needed to design a study that met the concerns of the community, as well as the requirements of the GLRI,” said Huset. The GLRI wants data on exposure to eight PCBs, Mirex, HCB, DDT and DDE, lead and mercury; the Minnesota laboratory added more than a dozen additional analytes to the test panel. Although mainly testing for chemicals resulting from potential environmental exposure, the lab chose to include a few extra, such as cholesterol and Hemoglobin A1C, which will allow study participants to follow up with their doctors to make personal health decisions. The lab is also studying the level of Omega-3 fatty acids in the participants, high levels of which are considered a positive effect of eating fish.
To conduct all of these tests, the clinic staff is “drawing 44 milliliters of blood, or about 7 tubes,” said Huset. Because each person’s blood must be divided for the varied laboratory tests and then delivered to more than one location, it was essential to design an easy-to-use sample kit; particularly since the blood is not drawn in-house, but at a clinic on the reservation. To reduce sample contamination and confusion, the kit has twenty different sample cups and vials with different colored caps.
A lab employee travels up to the clinic each Friday to collect the week’s frozen blood and urine samples, in part due to the clinic’s limited storage space, but more importantly, said Huset, because “the samples are precious and we worry about the potential for a power outage over the weekend, which would ruin them.”
Once the samples reach the MDH public health laboratory, some of them are then batched and sent to the Michigan Department of Community Health Laboratory or to private labs. Huset explained, “When the GLRI funding came through, one of the required tests was for PCBs, which affect other parts of the Great Lakes region, but are not a significant concern in Lake Superior or Minnesota.” Minnesota lab staff do not see a strong need for their facility to have this particular testing expertise, especially since PCB testing is relatively complex; also important, the GLRI funding did not come with an allowance to add new capacity. Fortunately, the Michigan laboratory has a robust PCB testing program.
“The contract work between the two states was more challenging than we expected. Both labs were willing participants, but we didn’t allow for the problems among the lawyers and the wording of the contracts,” said Huset. Once the technicalities were resolved, the partnership has worked smoothly.
Due to similar legal complications with a different laboratory partner, the Minnesota lab elected to allocate some of its own funds to develop testing capacity for 1-hydroxypyrene. “This was a test we wanted to develop anyway,” said Huset, “and it’s far less complicated than the PCB testing.” 1-Hydroxypyrene has been included in the study due to potential contamination in a Lake Superior watershed adjacent to a SuperFund site.
A great advantage to the researchers is that the Fond du Lac Band of Lake Superior Chippewa are “a very engaged and interested group,” said Huset. Participants have answered extensive questions about their personal history and habits.
A community’s engagement in a biomonitoring project is vital to its success. Prior to this GLRI project, the MDH ran four successful biomonitoring pilot studies, measuring arsenic levels in the urine of children who had played in contaminated soil, mercury in newborn screening collection cards, chemicals in pregnant women, and PFC levels in the blood of people affected by a contaminated community drinking water supply.
In the drinking water study, the participants’ commitment spurred the project on. “The community knew about their water contamination and were concerned. They pushed their legislators to push the funding through for the study,” said Huset.
In this case, PFC contamination had been discovered in 2004 in both private and municipal wells in a community. By the end of that year, the community’s exposure had been reduced through a combination of methods, including treating the municipal well, installing in-home filters, encouraging the consumption of bottled water, or transferring homes from private wells to the public water supply. In 2008, MDH conducted its initial biomonitoring study on people who had been exposed to the contaminated water and discovered that the levels of PFCs in their blood were higher than national levels. But then, in a follow up study in 2010, MDH discovered that the community’s average blood PFC levels had declined since 2008. The biomonitoring project demonstrated that the public health efforts undertaken in 2004 to reduce exposure had worked.
“This was a targeted public health action,” said Huset, “and it was effective.”
Part of the complexity of this process, in the pilot projects and again with the GLRI, is determining which chemicals to look for, what levels in people are safe, and when authorities should take action.
Noting the difference between measuring the chemicals levels in people and her earlier environmental work, Huset said, “People everywhere are very interested in what we do here, and they have a lot of questions.” Researchers do too, still trying to determine which pathways of exposure—such as diet, occupation or hobbies—predict contaminant concentrations in people. As studies like the GLRI project progress, it will be easier to identify public health actions that will protect people at increased risk of chemical exposure.
At the end of this study (sometime in 2014) researchers will have valuable new information about chemical exposure and human health. For more information about the Fond du Lac Band of Lake Superior Chippewa biomonitoring study, see www.health.state.mn.us/divs/eh/risk/studies/tribalstudy.html.
Without biomonitoring, public health practitioners face challenges in understanding whether environmental contaminants are actually being absorbed into people’s bodies. Given improvements in technology, the capabilities and expertise that exist in public health laboratories, and the increasing demand from the public for more information about chemical exposures, biomonitoring is poised to become an integral component of public health practice.
To learn more about biomonitoring, check out some of APHL’s Biomonitoring Resources:
Stay tuned for our soon-to-be-unveiled Meeting Community Needs page and of course, let us know if you have any feedback or suggestions.