New study finds elevated cancer rates near toxic San Jacinto River waste pits

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Texans living in a 250-square-mile area of Harris County that includes a hazardous Superfund site had abnormally high rates of certain types of cancer, according to a new assessment from the state’s health department.

The study, which was published earlier this month, analyzed cancer rates across 65 census tracts surrounding the San Jacinto River both upstream and downstream of the San Jacinto River Waste Pits Superfund Site, which is contaminated with carcinogenic waste. Between 2013 and 2021, the study found, people in the area had cancer rates above the expected range for cervix uteri cancer, leukemia, lung and bronchus cancer and lymphoma.

The Superfund site near Houston is contaminated with dioxins, which the Environmental Protection Agency says are highly toxic and can cause cancer, reproductive and developmental problems, damage to the immune system, and can interfere with hormones.

The Texas Department of State Health Services said the cancer assessment was not intended to determine the cause of the cancers or identify possible associations with any risk factors. But environmental advocates said the assessment’s findings renewed calls for the cleanup of the Superfund site, an effort which has faced several delays due to disputes over who is responsible.

Jackie Medcalf, founder and CEO of the environmental nonprofit Texas Health and Environment Alliance, called the state’s new study a wake-up call for state and federal officials.

“Our bodies are toxic soup and we cannot ignore that any longer,” Medcalf said Monday at a press conference at the San Jacinto Community Center.

The study also reviewed seven types of childhood cancer. Results showed cancer cases were within the range of what is expected based on cancer rates in Texas.

The site’s pits were originally constructed in the 1960s to dispose of solid and liquid pulp and paper mill waste from the International Paper Co. and McGinnes Industrial Maintenance Corp. During this time the EPA didn’t know the risk of such contamination.

As much as 200,000 cubic yards of highly toxic waste was dumped into the pits and later eroded allowing for contaminants to leak into the San Jacinto River. In 2008, the site was added to the EPA's National Priorities List for cleanup under the Superfund program, which ranks “the nation’s most serious uncontrolled or abandoned hazardous waste sites.”

For decades residents in the area say they unknowingly lived, swam, boated and fished near and on top of a hazardous waste site.

Gene Hennigan is a long-time resident of Lynchburg, an unincorporated community located in east Harris County and near the waste site. At the press conference Hennigan said he knows many people in the community who have suffered from cancer, including his wife and son who died of cancer.

“The list goes on,” he said. “We know the area is a cancer cluster by experience not by a study.”

THEA and local residents requested the state to study the area’s cancer rates.

In 2011 temporary armored caps were installed to contain toxic sludge at the site. However, six years later Hurricane Harvey damaged the caps, exposing the waste. Environmentalists and lawyers have argued the temporary cap is an insufficient fix and continue to push for expedited removal of the waste to prevent further human and environmental harm. Full remediation of the site has a price tag of $115 million.

Medcalf with THEA said she is frustrated that the EPA hasn't taken stronger action to clean up the site. The agency could take over the clean up. However, she’s hoping the Trump administration will prioritize the cleanup of hazardous waste sites, as she said he did during the prior administration by creating a Superfund Task Force.

THEA will be meeting with the state health department Tuesday and with the EPA later this week to discuss the cancer assessment’s findings.

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