About DDT & PCB Contamination

Photo showing MSRP Trustee Council and Staff in MSRP logo shirts.

MSRP Trustee Council and staff during a meeting on Santa Cruz Island in 2008.

From the late 1940s to the early 1970s, millions of pounds of DDTs and PCBs. were discharged into ocean waters off the southern California coast. Most of the DDT originated from the Montrose Chemical Corporation manufacturing plant located in Torrance, California. This site was one of the largest DDT manufacturing plants in the world. The plant released their wastewater into the collection system operated by the Los Angeles County Sanitation District. Eventually the wastes were discharged in the ocean through outfalls offshore of White Point, and a large amount of DDT contamination settled onto the Palos Verdes Shelf.  At the same time, large quantities of PCBs from numerous sources throughout the Los Angeles basin were also released into ocean waters through the same wastewater outfall pipe. The Montrose Chemical Corporation also dumped hundreds of tons of DDT-contaminated waste contained in drums into the ocean near Santa Catalina Island.

DDTs and PCBs are both toxic chemicals that are slow to break down in the environment. The chemicals can accumulate in plants and animals as they move up through the foodweb becoming more concentrated in higher predators. These pollutants contaminated fish, causing local authorities to warn against eating them and even ban commercial fishing in some cases. The pollutants also harmed birds—the DDTs caused their eggshells to be too thin to survive the nest, which decimated populations of bald eagles and peregrine falcons in the Channel Islands.

Decades later, more than 110 tons of DDTs and 11 tons of PCBs remain in the sediments at the ocean bottom. In 2001, NOAA and other federal and state agencies reached a settlement with the responsible parties, establishing the Montrose Settlements Restoration Program (MSRP).

Who is MSRP?

MSRP oversees the restoration of natural resources in the southern California marine environment that were harmed by DDTs and PCBs.

MSRP Trustee Council: