As scientists continue to uncover more damages associated with the undersea DDT dumpsite offshore Los Angeles, a cleanup operation remains elusive.

A research vessel in March discovered and photographed over 27,000 barrels lying on the sea floor about 12 miles (19.3 kilometers) offshore Los Angeles, some still leaking toxic waste, which scientists believe to be DDT.

A recent study conducted by the Marine Mammal Center in Sausalito, California, has found that approximately one in five California adult sea lions have died from cancer developed from a herpes virus in sea lions. Another study led by the same team showed that pollutants such as Polychlorinated biphenyls (PCBs), man-made industrial chemicals, and DDT play a significant role as co-factors in the development of this cancer. This is particularly relevant to Southern California, where most of the sea lion population gathers each year to breed.

Scientists have been aware of the negative effect of the toxic chemical on animals up the marine food chain, from zooplankton to pelicans to sea lions, and leading to mass die-offs of bees and insects as well as sea birds. DDT has also been associated with growing risks of breast cancer in women and testicular cancer in men, and other health problems.

Despite the growing concern, a cleanup action that could remove these barrels dumped decades ago remains out of sight so far.

An article published on Saturday on a local newspaper, the Catalina Islanders, noted that the push for the DDT waste cleanup is gaining support as the momentum is building to put pressure on the U.S. Congress and Environmental Protection Agency to address the issue.

Bloomberg reported that California lawmakers on April 29 passed a resolution 70-0 calling for action. That resolution needs U.S. Senate approval to be forwarded to Congress.

Los Angeles County Supervisors on May 4 voted to press the Environmental Protection Agency to expedite cleanup.

In a statement after being briefed by researchers, California Senator Dianne Feinstein described the finding as "one of the biggest environmental threats on the West Coast." She also noted the issue's severity requires a "whole-of-government approach" while expressing the wish to see companies responsible for the dumping being held accountable.

Dichloro-diphenyl-trichloroethane (DDT) is a highly toxic insecticide that was once used widely throughout the world, primarily as an agricultural pesticide. A global ban on its agricultural use was ratified by more than 170 countries in 2004. But until today, it remains a WHO-recommended tool against diseases like malaria. 

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