On average the THC content of pot has been increased over time. The numbers I gave are straight out of Wikipedia. You wanted to know, well here it is... Regardless of how much we know about weed, this info is from much smarter people, who know what they are talking about.. Type in Cannabis see for yourself...
These intensive horticultural techniques have led to fewer seeds being present in cannabis and a general increase in potency over the past 20 years. The average levels of THC in marijuana sold in United States rose from 3.5% in 1988 to 7% in 2003 and 8.5% in 2006.
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"Skunk" cannabis is a potent strain of cannabis, grown through selective breeding and usually hydroponics, that is a cross-breed of
Cannabis sativa and
C. indica. Skunk cannabis potency ranges usually from 6% to 15% and rarely as high as 20%. The average THC level in
coffeehouses in the
Netherlands is about 1819%.
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The average THC content of Skunk #1 is 8.2%; it is a 4-way combination of the cannabis strains Afghani indica, Mexican Gold, Colombian Gold, and Thai: 75%
sativa, 25%
indica. This was done via extensive breeding by cultivators in California in the 1970s using the traditional outdoor cropping methods used for centuries.
In proposed revisions to
cannabis rescheduling in the UK, the government is considering scheduling the more potent cannabis material as a separate, more restricted substance.
A Dutch double-blind, randomized, placebo-controlled, cross-over study examining male volunteers aged 1845 years with a self-reported history of regular cannabis use concluded that smoking of cannabis with high THC levels (marijuana with 923% THC), as currently sold in coffee shops in the Netherlands, may lead to higher THC blood-serum concentrations. This is reflected by an increase of the occurrence of impaired psychomotor skills, particularly among younger or inexperienced cannabis smokers, who do not adapt their smoking-style to the higher THC content.
[42] High THC concentrations in cannabis was associated with a dose-related increase of physical effects (such as increase of heart rate, and decrease of blood pressure) and psychomotor effects (such as reacting more slowly, being less concentrated, making more mistakes during performance testing, having less motor control, and experiencing drowsiness). It was also observed during the study that the effects from a single
joint lasted for more than eight hours. Reaction times were remained impaired five hours after smoking, when the THC serum concentrations were significantly reduced, but still present. When subjects smoke on several occasions per day, accumulation of THC in blood-serum may occur.
Another study showed that consumption of 15 mg of Delta(9)-THC resulted in no learning whatsoever occurring over a three-trial selective reminding task after two hours. In several tasks, delta(9)-THC increased both speed and error rates, reflecting riskier speedaccuracy trade-offs.
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