At 04:08 PM 10/5/98 +1300, J. Maxwell Legg wrote:
>> or hospitalizations due to herbs are so rare that
>> they're hard to find. The U.S. National Poison
>> Control Centers does not even have a category in
>> their database for adverse reactions to herbs."
>Though sometimes links come from the most surprising places. For
>instance, when I was in Vancouver to investigate a startup with a
>drug/laser therapy (good for throat cancer) it was revealed that the
>only place they could test their regime was in Amsterdam. It turns out
>that Amsterdam in 1994 had the highest rate of throat cancer in the
>World. I wonder why!
IAN: The 1993 National Household Survey on Drug Abuse  found that of Americans age 12 and above, approximately 34% had used cannabis ever, 9% had in the last year, and 4.3% had in the last week. The NHSDA for 1998  finds that 5.1% 12 years and over used in the last month (no cite for last week in press release).
In Holland, the Ministry of Welfare, Health and Cultural Affairs found that of residents of Amsterdam ages 12 and over, 25% ever used cannabis, 9.9% did in the last year and 6% did in the last week. When we consider that people in the U.S., unlike those in Amsterdam, will under report current use (criminal activity) for obvious reasons, I think we can conclude that there's not much statistical support for the theory you seem to suggest.
Also consider that in Amsterdam a whopping 42.7% had smoked tobacco in the last week , and yet in the U.S. only 30% of all people 12 years and over are tobacco users. 
BTW, J, did you see those questions I asked about zero?
"He who pursues learning will increase every day; he who pursues Tao will decrease every day." Lao Tzu (Tao Te Ching)