On April 26, 2021, a virtual briefing was hosted by Senator Dianne Feinstein with the purpose of reviewing results from a seafloor survey of a DDT dumpsite off the Southern California Coast, near the Santa Catalina Islands. DDT – a once-popular insecticide – is a highly toxic chemical that while banned from use, continues to haunt the California oceans and coastline due to decades of hazardous waste dumping. Researchers on the panel included Dr. Eric Terrill, Director of Marine Physical Laboratory at the Scripps Institute of Oceanography at UC San Diego, Dr. David Valentine, a professor of Earth Science at UC Santa Barbara, and Dr. Eunha Hoh, Professor of Environmental Health at San Diego State University. Throughout the congressional briefing, the researchers presented their findings on the dumpsite, which contains hundreds of thousands of DDT barrels, ecological and environmental impacts.
Dr. Eric Terrill began by presenting his findings as the researcher who initially discovered the metal barrels containing DDT approximately 1000 meters below the ocean surface. Although this was a known dumping ground for DDT, no documentation existed to inform local officials or Californians about the expansive presence. Dr. David Valentine spoke next where he presented video evidence demonstrating a DDT barrel that was leaking, as well as documented research that demonstrated DDT contamination in the surrounding sediment. The contamination is close to 40 times higher than the other largest known DDT dumping ground off the Palos Verdes Peninsula. Finally, Dr. Eunha Hoh presented her research which found the DDT contamination is already affecting marine mammal species. Although many environmental health researchers focus on 4-6 compounds of DDT, Dr. Hoh found 45 DDT compounds among bottlenose dolphins from the region. She also found that the DDT accumulation in the regional marine mammals was highest compared to other US regions and globally.
Dr. Euhna Hoh stated that this congressional briefing helps to get congressional support to begin a mitigation effort to prevent further DDT pollution in the region including determination of potential risks with the DDT barrels that are still largely unknown.
To learn more about this pressing issue, please read the LA times article.