Greenpeace on Thursday said McDonald's Corp. (MCD) was fueling the destruction of the Amazon rainforest by using soybeans grown in the region as feed for chickens that end up served in the fast-food chain's European restaurants.

In a reported entitled, "Eating up the Amazon," the environmental group said it has traced soy beans grown in illegally deforested areas of the rainforest to McDonald's restaurants, as well as other restaurant chains and supermarkets across Europe.

"Fast Food giants like McDonald's are trashing the Amazon for cheap meat. Every time you buy a Chicken McNugget you could be taking a bite out of the Amazon," Greenpeace forests campaign coordinator Gavin Edwards said by telephone from London.

McDonald's spokeswoman Anna Rozenich said the company was looking into the claims.

Soybean production in the Amazon has skyrocketed in recent years thanks to growing international demand and the development, by Brazilian government labs, of a type of soybean that can grow in the region's poor soil and punishing sun.

Environmentalists say that soybeans' success has driven up the value of cleared jungle, leading to a cycle in which cattle ranchers sell off pasture land to soybean farmers and then clear new areas, selling the wood to loggers.

Greenpeace argues that much of the soybean production in the Amazon is illegal because strict environmental regulations requiring landowners in the region to keep 80 percent of their forested areas standing, but these regulations are often ignored.

The southern Amazon region, where soybean production is growing most quickly, is also notorious for using so-called "debt slaves" to clear away jungle brush to prepare land for pasture and planting.

Debt slavery involves ranchers employing poorly paid workers and then forcing them to pay exorbitant prices for basic goods and transportation, ensnaring them in ever-deepening debt.

Greenpeace said its report is the result of a yearlong investigation using satellite images, aerial surveillance, previously unreleased government documents and on-the-ground monitoring to track Amazon soybeans.

"We've tracked shipments from farms that break the law to various silos and various ships into Liverpool and then followed the trucks to companies that produce chickens for McDonald's," Edwards said.

Edwards said that while American corporations like Archer Daniels Midland Co. (ADM) and Cargill Inc. were responsible for distributing the soybeans, most of the soy from the Amazon goes to Europe and China, because the U.S. is largely self-sufficient in terms of soy production.

To call attention to the report's finding, Greenpeace plastered many McDonald's restaurants in the United Kingdom with posters of Ronald McDonald wielding a chain saw. The group also had dozens of people in chicken costumes invade McDonald's restaurants, chaining themselves to the chairs, Edwards said.

Scientists say the deforestation reduces the area's rich biodiversity and contributes to global warming. Burning in the Brazilian Amazon releases about 370 million tons of greenhouse gases into the atmosphere every year, about 5.4 percent of the world total.

Brazil's rainforest is the size of Western Europe and covers 60 percent of the country's territory. Experts say as much as 20 percent of its 1.6 million square miles has already been destroyed by development, logging and farming.