Dumping of toxic wastes is contributing to cancer among wildlife, a new report says.

Scientists say that tumors on beluga whales, sea lions and other
animals are a warning signal. They call these animals “sensitive
sentinels of disturbed environments.”

The report, “Wildlife Cancer: a Conservation Perspective,”
published in the July edition of the cancer research journal Nature
Reviews Cancer, cites growing evidence from around the world that
pesticides, coolants and other toxic chemicals are causing a variety of
severe tumors in animals.

For example, the sea lions that are a major tourist attraction at
San Francisco’s Pier 49 are being diagnosed with deadly tumors around
their rear flippers and anuses. Frances Gulland, director of veterinary
science at the Marine Mammal Center in nearby Sausalito, told Newsweek
her center periodically gets calls from the pier reporting sea lions
crippled by horrible swellings. Gulland said 17 percent of the sea
lions brought to the center from the pier die of renal failure or
paralysis caused by tumors that travel up the genital tract and push
against the kidney and spine.

According to the journal article, sea lions that died of genital
carcinoma had an 85 percent higher concentration of toxic PCBs in their
system than other sea lions. PCBs, polychlorinated biphenyls, are
chemicals used in coolants and electrical transformers.

Gulland said that blubber samples of sea lions who died of cancer
also show high concentrations of the pesticide DDT. Many sea lions are
born near the Channel Islands, where 1,700 tons of DDT were dumped
before it was banned in 1972.

In Canada’s St. Lawrence Estuary, cancer was found to be the second
leading cause of death among dead beluga whales that were found beached
or drifting out to sea. The Saguenay River, which flows into the
estuary, is lined with aluminum smelters. The smelters are heavy
producers of polycyclic aromatic hydrocarbons (PAHs), proven
carcinogens for humans as well as animals.

Belugas feed from the bottom of the estuary, eating creatures like
the blue mussel. Blue mussels in the Sanguenay River area had PAH
concentrations 200 times higher than in adjacent areas.

It’s not just the whales. Smelter workers there have shown high
rates of lung cancer, while people in the area who drank from taps
supplied with surface water developed stomach and intestinal cancer.

“The more we contaminate the environment, the more we will see
problems,” Gulland told Newsweek. “If you dump a pollutant, it doesn’t
just go away.”

The report’s authors, biologists Denise McAloose and Alisa L.
Newton, work for the Wildlife Conservation Society’s Global Health
Program.

McAloose, like many other scientists, sees a connection between the
environmental role in cancer among wild animals and cancer prevention
among humans. “We need collaboration and cooperation across
conservation organizations, public-health communities, as well as
governments to make changes that have positive outcomes for animals and
the planet,” she told Newsweek. “Because that will have positive
impacts on the human population.”

Some scientists say that cancer prevention efforts focus too much
on personal lifestyle factors and not enough on large-scale
environmental factors that require concerted social attention and
government action.

At the same time, individuals have a role to play in reducing
environmental toxins. Amanda Wills, writing at Earth911.com, says the
new report highlights the danger posed by toxic home products like
bathroom cleaners getting into our air, soil and water.

According to the U.S. Environmental Protection Agency, Americans
generate 1.6 million tons of hazardous household waste per year. These
include paints, cleaning products, oils, batteries, pesticides and
antifreeze. The average home can accumulate as much as 100 pounds of
HHW in basements, garages, under the sink and in storage closets.

The wildlife cancer study, Wills writes, “is a lesson in proper
disposal. Household hazardous waste can be harmful to living things,
the environment and to the people handing them if they are not disposed
of properly.”

These products, the EPA warns, should not be poured on the ground, down the drain or into sewers, or thrown in the trash.