30 Years of Oil Pollution Threatening Western Amazon

The Western Amazon, an area of unparalleled biological and cultural diversity, may have been contaminated by widespread oil pollution over the last 30 years, according to a new study.

Most of the world's tropical rainforests are oil and gas goldmines. Oil production in the Western Amazon began in the 1920s and peaked in the 1970s, but current growing global demand is stimulating a renewed growth in oil and gas extraction - nearly 70 percent of the Peruvian Amazon was tapped for oil between 1970 and 2009.

Spanish researchers studied 18 wastewater dumping sites from 10 different Amazon tributaries, and looked for nine different pollutants, including lead, mercury and cadmium. After conducting chemical analyses using data from Peruvian public agencies and oil companies over a 30-year period, their findings raised some serious concerns.

"We found that 68 percent of the samples were above the current permitted Peruvian limits for lead concentrations, and 20 percent of the samples above permitted cadmium levels," researcher Raúl Yusta Garcia said in a statement.

They also compared pollution levels of upstream and downstream of some of the dumping sites. Astonishingly, some chlorine levels averaged 11 times higher downstream of the wastewater dumping site than it had been upstream.

Oil extraction may have started to decline around 2008, but this first-of-its-kind study shows that it's making a comeback due to increasing demand.

"This increase in pollutant levels is not just due to oil spills, but to the drilling and extraction process," added lead researcher Antoni Rosell-Mele. "These processes have not been effectively monitored in remote areas until now."

Rosell-Mele adds that such practices not only impact the environment and local wildlife that feed on these large grounds, but humans as well. It's possible that pollutants may find their way into our food, implicating negative health effects as well.

Hopefully, the $215 million fund recently created by the Brazilian government and World Wildlife Fund to ensure the Amazon's long-term protection will help in controlling oil pollution levels.

This study will be presented at the Goldschmidt conference in Sacramento, Cali.