July 1 (Bloomberg) -- Cocaine and marijuana have been tried by more Americans than residents of 16 other countries surveyed, researchers said, even though tough U.S. laws seek to discourage the use of the drugs.

In the U.S., 42 percent said they had used marijuana and 16 percent had tried cocaine, according to the study published in the journal of the Public Library of Science. In the Netherlands, where people can go to cafes to smoke marijuana, 20 percent have tried that drug and 1.9 percent sampled cocaine.

The higher incidence of drug use in the U.S. may be linked to the nation's relative affluence, not its anti-drug laws, said James Anthony, chairman of the epidemiology department at Michigan State University's medical school in East Lansing, Michigan, and an author of the study.

``Drug use is related to income, but does not appear to be simply related to drug policy, since countries with more stringent policies toward illegal drug use did not have lower levels of such drug use than countries with more liberal policies,'' the study's authors wrote.

New Zealand, at 4.3 percent, and Spain, at 4.1 percent, reported the highest incidences of cocaine usage after the U.S. The lowest was China, where no one said they had used the drug, followed by Nigeria and Ukraine at 0.1 percent each.

The 17-country study surveyed about 54,000 people from 2002 through 2005. Among other countries in the study were Colombia, Germany, Israel and Nigeria.

``In the Netherlands, despite a less restrictive approach, the population hasn't taken up cannabis smoking to the extent that's true in U.S., or New Zealand,'' Anthony said.

U.S. Comment

Trying to find a link between drug use and drug enforcement doesn't make sense, said Tom Riley, spokesman for the U.S. Office of National Drug Control Policy in Washington.

``The U.S. has high crime rates but we spend a lot on law enforcement and prison,'' Riley said yesterday in a telephone interview. ``Should we spend less? We're just a different kind of country. We have higher drug use rates, a higher crime rate, many things that go with a highly free and mobile society.''

The study released yesterday was funded by the National Institute on Drug Abuse, part of the U.S. National Institutes of Health.

It also included questions about tobacco and alcohol usage. The Ukraine, at 97 percent, had the most people who said they tried alcohol, and South Africa, with 41 percent, the fewest. The largest share of people who said they had smoked cigarettes was in the U.S., 74 percent, while Nigeria, at 17 percent, had the fewest people who had smoked.

To contact the reporter on this story: Aliza Marcus in Washington at amarcus8@bloomberg.net

Last Updated: July 1, 2008 00:01 EDT