EPA finds cancer-causing chemicals over screening levels near Fifth Ward creosote site
Some vapor samples taken near the Union Pacific rail yard in Fifth Ward include cancer-linked toxins like benzene at levels that require more safety testing. The U.S. Environmental Protection Agency (EPA) has identified potentially dangerous levels of toxic chemicals in several new vapor samples taken near a Union Pacific rail yard in Fifth Ward, Houston. The area has been plagued by residents for years, blaming the creosote process used to treat rail ties at the site for contributing to elevated cancer rates. The EPA's new test results reveal that 17 of 51 samples contained cancer-causing benzene above the EPA's screening levels in 17 of the samples. The samples were among 117 collected by contractors working on new EPA and Union Pacific-led testing. The partial data does not yet indicate that the chemicals present a current danger or that they will be cleaned up.
Published : a month ago by Rebekah F. Ward, Staff writer in Environment
The EPA has identified potentially dangerous levels of toxic chemicals in several new vapor samples taken near a Union Pacific rail yard in Fifth Ward, where residents have for years worried that the creosote process once used to treat rail ties at the site had contaminated their properties and made them sick.
Residents still living on top of an underground plume of creosote-contaminated water blame it for the area's elevated cancer rates, though the company said for years that they doubted the connection. In 2019, the zone was named a cancer cluster by Texas' Department of Health and Human Services.
The U.S. Environmental Protection Agency's new test results reveal chemicals, including cancer-causing benzene, at concentrations above the EPA's screening levels in 17 of 51 samples taken from sanitary sewers, storm sewers, monitoring wells and soil gas probes in the area.
The 51 samples were among 117 collected by contractors working on new EPA and Union Pacific-led testing begun in November to assess the contamination's impact on residents. EPA representatives said they do not know when the lab would finalize results of the remaining 66 samples.
Sandra Edwards, a longtime resident of Fifth Ward who lives on top of the creosote plume and has fought off cancer, said the initial results felt validating. When the new testing was starting, Edwards said earlier, she was relieved that action was being taken but worried that it had been so long since the wood treatment operation run by Southern Pacific were shut down in 1984 that the testing would come up short.
"These people thought we was crazy," Edwards said. "This is the beginning to a good ending. There's something happening, now get down to the bottom of it."
"EPA expects the vapor intrusion investigation to continue into the summer and will continue to publish results from the investigation as data are finalized," said Jennah Durant, a regional spokesperson for the agency.
The partial data does not yet indicate the chemicals present a current danger or that they will be cleaned up: the EPA uses risk-based screening levels at sites with legacy pollution "to determine if potentially significant levels of contamination are present to warrant further investigation," the agency said online. These screening levels are often more sensitive than health standards require, to make sure the agency knows where to take a deeper look.
Union Pacific said the initial vapor tests were just the beginning of the company's process with the EPA to conduct "extensive soil and air screening in the Fifth Ward neighborhood."
Four of the 17 samples that contained toxic chemicals above federal screening levels included contaminants that the EPA considers creosote-related, including cancer-causing benzene and likely carcinogens napthalene and ethylbenzene. Other chemicals in the samples that are not typically linked to creosote contamination included chloroform, which can be used as an industrial solvent.
In 2022, the Fifth Ward rail yard was linked to possible additional toxic chemicals when the Houston Chronicle found workers had mixed creosote with hazardous waste from other contaminated Houston-area Superfund sites to extend the wood-preserving substance.