A few years back, while visiting San Francisco, I saw the famous sea lions of Pier 39. They looked content then, basking on the docks, but the throngs of tourists (myself included), did not know that this sea lion colony is plagued by Otarine herpesvirus-1, a genital cancer that can cause painful tumors, paralysis, and death.
This condition may sound like a tragedy born in the natural world, but a recent report in the scientific journal Nature Reviews Cancer implies otherwise. “*Wildlife Cancer: a conservation perspective,” links human pollution with rising rates of cancer in wild animals, turning the finger of blame away from mother nature and pointing it squarely at us.
The report states that sea lions who died from genital carcinoma had an 85 percent higher concentration of toxic PCBs – a chemical used in coolants and transformers – in their systems than other sea lions. Sea lions who died of cancer also show high concentrations of the banned pesticide DDT, which was dumped near a sea lion birthing place in the Channel Islands before being outlawed in 1972.
The report provides evidence of pollution-related cancers in other marine mammals as well. In Canada’s St. Lawrence Estuary, beluga whales are endangered by pollution from aluminum smelters lining the Sanguenay River. Belugas feed where the polluted river meets the estuary, scooping up mussels that show a concentration of toxic polycyclic aromatic hydrocarbons (a by-product of the factories) 200 times higher than in the surrounding areas. Among whale carcasses found in the area, cancer is the second leading cause of death. Cancer rates are also high among humans working in the factories and drinking surface water along the Sanguenay.
Although the sea lions of San Francisco still contain DDT dumped three decades ago, Newsweek reports that removing the carcinogen can significantly reduces cancer rates in some situations, citing fish along Ohio’s Black River, whose life expectancy rose and cancer rates dropped dramatically after a polluting plant on the river closed down.
The full effects of pollution on cancer has yet to be conclusively determined, but emerging research such as this is hard to ignore. Improperly disposing of dangerous chemicals into our environment, be it 1,700 tons of toxic waste or just that paint thinner sitting in your garage, alters ecosystems, turns once-healthy wildlife into what the study calls “sensitive sentinels of disturbed environments."
Source: BecauseAction.com
