LA Seabed Barrel Graveyard Exposes Caustic Waste, Not DDT

Researchers from UC San Diego’s Scripps Institution of Oceanography found caustic alkaline waste in barrels dumped off Los Angeles decades ago, not the DDT waste expected. An estimated 300,000 barrels were dumped between the 1930s and 1970s, with about 27,000 still visible on the seafloor roughly 3,000 feet deep. Leaking barrels have left white halos and altered the seabed’s chemistry, potentially disrupting nitrogen and sulfur cycling and microbial communities for centuries. Cleanup is being approached cautiously because contents and sealed-status are uncertain, and researchers call for further study; the findings were published in PNAS Nexus.