After years of controversy, the Central Valley Regional Water Quality Control Board in California assured the public that eating local crops irrigated with oil field wastewater “creates no identifiable increased health risks,” based on studies commissioned as part of an extensive Food Safety Project. Yet a review of the science and interviews with a public health scientist affiliated with the project and other experts, Liza Gross and contributor Anne Marshall-Chalmers reported, showed little evidence to support the board’s safety claims. GSI Environmental, a “neutral, third-party consultant” retained by the board to conduct the studies, had regularly worked for the oil industry, Gross found. More than a fifth of the chemicals GSI identified, and 60 percent of those deemed most likely to pose a health risk, lacked both toxicity information and approved testing methods. The water board conceded that data gaps left “potentially significant unknowns.” Colorado State University’s Thomas Borch, a specialist on treating and reusing oilfield wastewater, said GSI’s data was “way too limited” to reach conclusions about the lack of toxicity of the chemicals in the wastewater and to say they posed no identifiable health risks. Judge Lauren Weber of Kaiser Health News said the reporting by Gross “exposed not just the conflicts of interest, but also painstakingly explained the science behind it all.” Judge Robert Lee Hotz called the story “an impressively thorough investigation” into the potential risk to agricultural irrigation affecting most of the U.S. almond crop. The reporting, he said, “is in the best tradition of science journalism in the public interest.” Liza Gross said she was dubious when California regulators said it was safe for farmers to irrigate crops with oil companies’ wastewater. “But what I found shocked me,” she said. “Regulators’ so-called neutral consulting firm actually worked for the oil industry and produced data that couldn’t support the conclusion about safety—no reputable journal would have published the work. I’m grateful for the recognition this award brings to the arduous, time-consuming reporting it takes to parse technical, controversial science, and lucky to work for an outlet that supports this type of work.”
