Between the late 1940s and the early 1970s, the Montrose Chemical Plant discharged an estimated 1,800 metric tons of the pesticide DDT through the Los Angeles County Sanitation Districts' wastewater system into the Pacific Ocean off the Palos Verdes peninsula. Montrose also dumped hundreds of tons of DDT-contaminated acid sludge into the ocean near Santa Catalina Island. Other Los Angeles-area industries also flushed PCBs into the ocean via the local wastewater system.

Scope of Injuries

DDTs and PCBs have injured and continue to injure natural resources that live in and around the coastal waters of Southern California. The specific injuries for which the trustees received natural resource damages include breeding failures in bald eagles and peregrine falcons, and contamination levels in fish that have led the state of California to issue fishing restrictions.

Sports and commercial fish. The state of California has issued fish consumption advisories for many commonly caught saltwater fish in certain areas along the Southern California coast (approximately 50 species in 8 groups). The advisories recommend that people limit their consumption of certain fish in some locations. A particular species, white croaker, is so contaminated in some locations that the state advises people not to consume it at all. The state has also banned commercial fishing for white croaker near the Palos Verdes Shelf. Read the California state fishing advisories.

Bald eagles and peregrine falcons. Because DDTs and PCBs are slow to break down, they bioaccumulate and become more concentrated in predators. When feeding on food contaminated with DDTs and PCBs, animals at the top of the food web, like bald eagles and peregrine falcons, can accumulate high concentrations of these chemicals. DDTs, particularly, cause abnormalities in eggs, including thinning of eggshells, and have harmed bird populations in the Southern California Bight. When DDTs were heavily used in the United States, populations of many birds, including bald eagles and peregrine falcons, declined. After the United States banned the use of DDTs in 1973, populations of bald eagles and peregrine falcons rebounded almost everywhere except in the Southern California Bight.

Peregrine falcons have returned to the Channel Islands through reintroduction efforts, but they continue to experience eggshell thinning and have not reached their population levels prior to the contamination. In the 1980s, efforts began to reestablish bald eagles on Catalina Island. However, contamination levels in their prey are still so high that they continue to experience reproductive problems and must be maintained through an active annual chick fostering program.

Seabirds. Many seabird species, including the California brown pelican and the double-crested cormorant, were severely impacted in the past by the discharges of DDTs to the coastal waters of the Southern California Bight. Although the evidence is not conclusive regarding continuing injuries to these birds on the same scale of the continuing injuries to bald eagles, the Trustees considered seabirds and their habitats to be an appropriate recipient for restoration actions, and are targeting seabirds that have demonstrated severe or significant eggshell thinning and/or seabirds whose DDT egg residues were significantly elevated in their colonies of the Southern California Bight. These birds include: double-crested cormorants, Brandt's cormorant, California brown pelicans, western gulls, ashy storm-petrels, Cassin's auklets, pelagic cormorants, and pigeon guillemots.

By present estimates, DDTs and PCBs will continue to contaminate marine resources and birds in Southern California for future generations. According to U.S. Geological Survey studies, a substantial amount of DDTs probably will remain in the sediments and biota of the Palos Verdes Shelf for decades.