Houston residents’ chemical exposure increased after Hurricane Harvey, study finds

Researchers at Oregon State University used silicone wristbands to measure Houston residents’ increased exposure to hazardous chemicals in the aftermath of Hurricane Harvey in 2017.

The wristbands recorded exposures to 162 different chemicals, including pesticides, flame retardants, industrial compounds, phthalates and polycyclic aromatic hydrocarbons.

Researchers followed study participants a year after Harvey to get closer to a baseline so they could analyze which exposures were caused by the storm. On average, 75% of chemicals detected at both time points were found at higher concentrations immediately after the hurricane, but people’s baseline exposure was already high.

“Houston is one of our most industrialized cities,” said co-author Kim Anderson, chief of OSU’s Department of Environmental and Molecular Toxicology and inventor of the study’s wristbands. “When we look a year after the storm, we see that several neighborhoods closer to industrial areas – socio-economically disadvantaged neighborhoods – had higher concentrations of chemicals from the outset, and this was only exacerbated when the storm hit. hurricane has arrived.”

Silicone wristbands absorb chemicals from air and skin contact, making them a useful screening tool. Anderson has used them in similar studies in Africa, Europe and South America.

Many of the chemicals recorded in the Houston study have not yet been thoroughly tested for their potential health effects, the researchers said. But some heavier polycyclic aromatic hydrocarbons have been shown to cause cancer, and exposure to phthalates can have adverse effects on reproductive health.

The research team began work almost immediately after Harvey landed, receiving approval for sampling within a week and distributing bracelets for the study to 173 residents within three weeks.

“At that time, the flooding was still happening. I think that’s a huge strength of this study,” said co-author Diana Rohlman, associate professor in the College of Public Health and Human Sciences at the University. USO. “From a public health perspective, this is the data that people want: ‘I’m actively flooding, I’m actively cleaning my house; what am I exposed to right now?'”

This rapid response is important, she said, because previous disaster responses have been slowed by up to six months pending test approvals, such as with the 2010 Gulf of Mexico oil spill.

The team also conducted a small pilot study with 27 residents within the first 10 days after Harvey struck. These 27 samples contained the highest number of chemicals of any study conducted by the researchers anywhere in the world, Anderson said.

A major concern in Houston was the number of Superfund sites that were damaged by flooding after Harvey. Superfund sites are areas whose pollution is severe enough that the Environmental Protection Agency considers them to be in need of federal mitigation efforts.

A 2020 report from the Shriver Center on Poverty Law found that 70% of Superfund sites nationwide are located within one mile of federal housing projects, highlighting the disproportionate burden of pollution placed on low-income communities. , most often communities of color.

Oregon State has nine total Superfund sites; the city of Houston has 41. Of those, 13 were flooded during the hurricane, but the total effect of that flooding is unclear, the researchers said.

“There’s this pocket of contaminants that mobilized in the water, but they were also in five feet of rain, which could be a dilution factor,” Anderson said.

During the hurricane’s first days, 89 industries reported “unintentional releases,” Rohlman said. Some Houston factories closed in the wake of the storm, reducing their emissions, but the state of Texas also granted emergency exemptions to clean air requirements for manufacturing plants, so that some may have polluted more, researchers said.

In addition to the chemicals released by the storm damage, the wristbands also recorded many of the chemicals used in common household cleaners, which residents were exposed to when cleaning their homes after the flood.

Until more research is done on the individual chemicals recorded in the study, Rohlman said they could not offer specific safety information other than the standard recommendation to wear gloves and masks when cleaning up flooded areas.

Other authors of the Houston study were Samantha Samon, Lane Tidwell and Peter Hoffman of OSU and Abiodun Oluyomi of Baylor College of Medicine.