The San Diego County District Attorney’s Office is seeking records from the Mexican government to determine whether Tijuana-based industrial businesses might be contributing to cross-border pollution, officials said Thursday. While billions of gallons of sewage flow into the county via the Tijuana River on an annual basis, jeopardizing the health of South Bay residents, the D.A.’s Office cited a recent report from nonprofit environmental organization San Diego Coastkeeper that found industrial pollutants were also present in the water. Among the chemicals detected were volatile and semi-volatile compounds such as heavy metals, pesticides, PFAs, acetone, phenols and benzoic acid. Coastkeeper’s report, the 2025 Tijuana River Valley Water Quality Report, stated that the findings pointed to pollutants coming from Tijuana factories known as maquiladoras.