CORVALLIS, Ore. - As weary Houstonians mop up after the freakishly powerful Hurricane Harvey, which dumped an estimated 27 trillion gallons of rain over Texas and Louisiana, they face a dismaying possibility: contamination from toxic chemicals lurking in the receding floodwaters.
Some Houston residents are taking part in an Oregon State University-led study to find out exactly what chemicals they’ve been exposed to in Harvey’s muddy aftermath. They’re wearing a simple silicone wristband invented by an OSU researcher — a “personal passive sampler” that picks up molecules of organic chemicals similarly to the way your own cells do.
After a week, the citizen scientists will mail the wristbands to the laboratory of Kim Anderson, environmental chemist in OSU’s College of Agricultural Sciences. She and her colleagues will analyze them for chemical contamination and give a customized report to each of the residents who wore them.
There are 13 Superfund sites in and near Houston, one of which — the San Jacinto River waste pits — has not yet been remediated. The city also is home to oil refineries and other industrial sites whose effluents can contaminate water and air.
“Community members were asking for some way to measure their chemical exposure after the flooding from Harvey,” Anderson said. “We were all geared up and ready to go, so we offered to come down, and they said, ‘Yes, please.’”
Anderson and her colleagues Peter Hoffman, Lane Tidwell and Holly Dixon, flew to Houston on Sept. 19, three weeks after the killer storm pummeled the city, as residents were tackling the Herculean cleanup task. The OSU team spoke at a community meeting in Houston’s Highlands and surrounding areas, which lie close to Superfund sites.
They offered residents the opportunity to take part in the wristband study. “We had about 50 people at this meeting, and we enrolled everybody who wanted a wristband, about 36 people,” Anderson said.
It took a while, she said. “There were questionnaires, consent forms, and other information to be gathered. But we stayed late until everybody was enrolled.”
Anderson, a professor in OSU’s department of environmental and molecular toxicology, is collaborating with Baylor College of Medicine, Texas A&M University and the University of Texas on the project. Baylor researchers distributed the passive samplers to residents of other flooded Houston neighborhoods later in the week.
OSU was able to respond first, Anderson said, because her team had already sought and received approval to conduct post-disaster research involving people.
Back in 2010, when she and her team came to the Gulf of Mexico to sample air and water after the Deepwater Horizon oil spill, “we were able to do environmental sampling, but we couldn’t sample individual people’s exposures because we didn't have an IRB” — authorization from a university’s Institutional Review Board to study human subjects.
“Any time you’re doing research on human subjects, there’s a detailed approval process you have to go through,” she said, “and it can take months.”
After Deepwater Horizon, Anderson applied for and received a “blanket IRB,” giving her team the authority to act quickly to gather information on human subjects, in case of a future disaster.
“So when Harvey hit, I knew we could help residents understand their individual exposures from the flooding,” said Anderson. “And I knew we could make it happen within the critical time period just after the flooding.”
The wristbands are made of soft silicone and come in a variety of colors. “We wanted to make the device lightweight and easy, fun to wear,” said Anderson.
How do they work? The material is porous, and chemically it’s very similar to a human or mammal cell, Anderson said. Molecules of contaminants lodge themselves in the silicone the same way they’d go into the cells in your body.
The wristband can sample thousands of organic chemicals: pesticides; hydrocarbon pollutants from wood or fossil-fuel combustion; benzene and toluene used in industrial solvents; and many others. It won’t pick up inorganic pollutants such as lead, chromium or carbon monoxide.
Anderson’s OSU laboratory is part of the Superfund Research Program, which has funding from the National Institute of Environmental Health Sciences. Anderson is looking for funding to do a 6-month follow-up study on the Houston residents’ chemical exposure.