Legaliseringsguiden, genomgång av ... - PDF Archive

Marijuana Potency Monitoring Project hos University of Mississippi är den främsta källan när det
gäller cannabispotensen då dessa har gjort mätningar på amerikanska beslag sedan 1970-talet.
Manenn som sammanställer rapporterna heter Dr. Mamoud Elsohly.
Bakgrund: NIDA och DEA bestämde 1975 att alla beslag som DEA gjorde som vägde mer än 90 kg
skulle analyseras. Gränsvikten minskade senare till 75 kg. Förutom beslag från DEA som främst görs
vid gränserna så började projektet senare inkludera beslag från polisen, som till större andel består av
marijuana som odlats i landet.
Analys: Andelen sinsemilla (obefruktade honplantor som alltid är potentast) har ökat betydligt sedan
mätningarna började. Det totala potensvärdet som används i "cannabis är xx-gånger starkare än
yyyy"-argumentet bygger på fördelningen mellan proverna från beslagen, vilka inte nödvändigtvis
återspeglar fördelningen av produkterna på marknaden.
Man kan även se att 1967-1982 så var det förhållandevis få beslag om året som låg till grund för
potensbedömningen, under 300 om året. Först 1974 hade man kommit över 100 om året. 1983
kommer man över 1000 analyser om året.
“
ElSohly's only peer-reviewed discussion of the project is conservatie in his claims
and generalizations. Prior to 1972, there were only 65 samples examined and few of
these came from the main sources of later years -- DEA and state seizures. In 1974,
the number of samples only exceeded 100 for the first time, but none of these 114
samples in 1974 were of domestic origin. Most of the imported samples of 1974 and
1975 were of Mexican origin packaged as compressed plant material (kilobricks).
Not all imported marijuana plant material is of low potency but Mexican kilobricks of
the early 1970s surely were. In 1974 and 1975, the delta-9-THC concentrations in the
kilobricks were 0.40% and 0.47% respectively. The percentage of all samples made
up of this Mexican material was approximately 50 and 60% in the same two years. In
1975, kilobrick samples numbered 88 while loose plant marijuana samples
numbered only 58. The calculation used to generate the 0.4 and 0.5% potencies also
employed normalized statistics in which the relatively high weight of the kilobrick
seizures was factored in and yielded the lowest average concentration of THC. In fact,
even using the Mississippi data, the arithmetic mean concentration of delta-9-THC in
1974 and 1975 was approximately 1%. Mikurya and Aldrich believe that sinsemilla
agriculture was well understood in California in the 1970s and had made a
contribution to the average THC concentration of commercial marijuana by that time.
The Mississippi Project analyzed no sinsemilla samples in 1974-1976 and did not
exceed 15 samples until 1980
— John P. Morgan, M.D. Department of Pharmacology, City University of New York
Medical School [4]
”
“
Marijuana potency is expressed as the percentage weight of the sample contributed
by delta-9-THC. This active chemical was not identified until 1966 and potency was
rarely measured before 1970. Reports from street drug laboratories assessing
anonymously submitted samples indicate that from 1970 to 1975, commercial
marijuana averaged 2-4 percent THC.
In 1975, a federally-funded marijuana potency monitoring project was established at
the University of Mississippi. Essentially all plant samples tested have been seized by
the DEA or state criminal agencies. The summer 1993 quarterly report traces the
project's entire experience.
Since 1974, approximately 20,000 samples of marijuana have been analyzed. The
averge THC content of all samples is 2.93%. Since the laboratory first received more
than 250 seizures annually in 1981, there has been no discernible pattern of
increased potency. The highest average potency was 3.96 percent in 1984. The
lowest was 1.9 percent recorded in the last complete year tallied, 1992. These 1992
figures came from the assessment of approximately 3500 seized samples with total
weight exceeding 1.5 million pounds.
— John P. Morgan, M.D. Professor i Pharmacology Feb. 18, 1994 [5]
”
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