Western Amazon is at Risk of Oil Pollution: 30-Year Contamination Period

It turns out that the Western Amazon may be in more trouble than we thought. Scientists have found that this region may have been contaminated by widespread oil pollution over a staggering 30-year period. The findings could have implications for the future of this area's ecological health.

Most of the world's tropical rainforests actually contain oil and gas reserves. Oil production in the Western Amazon in particular peaked in the 1970s, and a growing global demand has stimulated a renewed growth in oil and gas extraction; nearly 70 percent of the Peruvian Amazon was tapped for oil between 1970 and 2009. Now scientists have taken a closer look at the impacts of this oil extraction in the Western Amazon.

"We looked at measurement in 18 wastewater dumping sites from 10 different Amazon tributaries," said Raul Yusta Garcia, one of the researchers, in a news release. "We were able to pull together records over a 30 year period, from 1983 to 2013, allowing us to measure variations in nine different pollutants, such as lead, mercury and cadmium. 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."

The researchers also compared pollution upstream and downstream of some of the dumping sites. This revealed that chlorine levels averaged 11 times higher downstream of the wastewater dumping sites. This, in particular, showed that increasing demand could cause increasing pollution.

"There are no published studies to date that report the pollution impact of oil extraction activities in remote pristine rainforests," said Antoni Rosell-Mele in a news release. "Our results show that contamination is widespread in these areas. This increase in pollutant levels is not just due to oil spills, but to the drilling and extraction process. These processes have not been effectively monitored in remote areas until now. Some of this pollution may feed its way into the human food chain and certain of the areas affected by oil spills on land are feeding grounds for large wildlife, including endangered species."