June 13, 2014
National Geographic photos show an illegal road within Ecuador's Yasuni National Park. Photo © Karla Gachet. Click to enlarge.
Led by Antoni Rosell-Mele of the Universitat Autònoma de Barcelona, the team assembled a database of chemical analyses taken from 18 wastewater dumping sites from 10 different Amazon tributaries from 1983 to 2013. They looked at nine pollutants including lead, mercury and cadmium, finding high levels of contamination.
"We found that 68% of the samples were above the current permitted Peruvian limits for lead concentrations, and 20% of the samples above permitted cadmium levels," said co-author Raúl Yusta Garcia, also of the Universitat Autònoma de Barcelona, in a statement.
Oil and gas blocks in the western Amazon. Solid yellow indicates blocks already leased out to companies. Hashed yellow indicates proposed blocks or blocks still in the negotiation phase. Protected areas shown are those considered strictly protected by the IUCN (categories I to III). Image modified from Finer at al (2008).
Rosell-Mele added that pollution results from various oil development activities, including spills, drilling, and extraction.
"There are no published studies to date that report the pollution impact of oil extraction activities in remote pristine rainforests," the scientist said. "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".
The researchers presented the findings at the Goldschmidt Conference, which focuses on geochemistry.
Oil production began in the Western Amazon in the 1920's and after peaking in the 1970's has experienced a resurgence in recent years with booming oil prices. Ecuador recently approved oil drilling within protected areas that house the world's highest levels of biodiversity. Meanwhile Peru has auctioned off oil exploration rights to 70 percent of the Peruvian Amazon. In 2013 the Peruvian government declared a state of emergency over contamination in the Amazon.