The drugs were supposedly being sold as research chemicals, but buyers’ e-mail names included acidtripo420, ecstasylight, ravergirlny and psychedeleic—stoner, the Drug Enforcement Agency said.

An indictment handed down Wednesday against Michael Burton, 25, of Las Vegas, accuses him of causing a man’s death — not as a murder charge but as a way to increase the sentence if he’s convicted.

Burton’s roommate, Keith Russart, 25, also was arrested. Both were charged on four counts of distributing illegal drugs, said U.S. Attorney David Dugas of Baton Rouge. The charges carry a prison term of 20 years to life in prison.

The eight others arrested this week live in Arizona, Georgia and California. The sales occurred in various states. All eight face conspiracy charges.

Three of five Web sites selling the drugs could not be reached Thursday. The fourth brought up a screen stating that the DEA had “restrained” it.

The fifth — Burton’s site — carried a 650-word statement that said, among other things, that the drugs were for research and not for human consumption.

The DEA alleged the suspects distributed three groups of hallucinogens and other drugs: tryptamines and phenylethylamines, which are related to important brain chemicals; and piperazines, which are related to a drug used for pinworms and roundworms.

“Many young people are led to believe that these substances are a form of ‘legal’ Ecstasy or LSD because they produce similar hallucinogenic effects. ... Many have the false impression that they are not as harmful or addictive as mainstream drugs such as heroin or cocaine,” the DEA said.