Moscow ? Afghan opium kills more people every year than any other drug on the planet, claiming up to 100,000 lives annually, according to a United Nations report released Wednesday.

Although U.S. officials have pointed to the last two years of lower production in Afghanistan, the country still produces 90 percent of the world’s opium, which the report says now threatens to sow havoc in much of Central Asia.

“The catalog of casualties caused by Afghan narcotics is gruesome,” Antonio Maria Costa, the executive director of the U.N. office on drugs and crime, says in a note in the report’s summary. “We need to go back to the dramatic opium addiction in China a century ago to find comparable statistics.”

In addition to drug-related deaths, Afghan opium and heroin pay for weapons that anti-U.S. insurgents use to kill American troops.

From 2005 to 2008, Taliban insurgents in Afghanistan earned an average annual income of some $125 million from the opium trade, not including money gained from drug-processing facilities or other related business in neighboring Pakistan, according to the report.

The Afghan opium crop, used to produce heroin, dropped from 7,700 metric tons in 2008 to 6,900 this year, but because of massive overproduction there are now more than 12,000 metric tons of opium in stockpiles, enough to meet world demand for more than two years. Criminal and insurgent groups probably are holding most of those reserves, the U.N. said.

The U.N.’s findings sounded a strong warning about the Central Asian opium-trafficking route, which has become a virtual conveyor belt for heroin between Afghanistan and Russia, referring to it as the “most sinister development yet.”

“The perfect storm of drugs, crime and insurgency that has swirled around the Afghanistan-Pakistan border for years is heading for Central Asia,” Costa said. “If quick preventive measures are not put into place, a big chunk of Eurasia could be lost.”