HERBAL CANNABIS GROWN and used in Ireland is more potent than the imported variety, the National Advisory Committee on Drugs (NACD) has said.

In a report from its forensic science lab the NACD has warned of the dangers of cannabis grown in Ireland which contains a higher level of Tetrahydrocannabinol or THC, which can cause psychotic episodes, than quantities of the drug that are imported.

It also expressed concern about the “surges” in cannabis cultivation in Ireland overall.

The study stated that the reason for higher potency was because of the way the plant was grown indoors, producing herbal cannabis such as ‘skunk’ or ‘weed’.

“While the majority of cannabis products seized by An Garda Siochana in Ireland are thought to be imported from countries where it is specifically grown for exportation, there is concern about the surges in cannabis cultivation here in Ireland,” NACD chair Dr Des Corrigan said.

While cannabis grown in Ireland has high levels of THC it lacks the substance known as CBD which can mitigate the psychotic effects of THC when taken together.

The NACD said that samples  taken from seizures of cannabis herb in Limerick, Cork, Tipperary, Bandon, Fermoy and Dublin has shown cannabis cultivated in Ireland had very high THC levels and very low CBD levels compared to imported herb or resin, which is known as ‘hash’.

As an example cannabis which was seized in Limerick and suspected as having been imported contained a 5 per cent level of THC compared to cannabis seized in Bandon and suspected as having been cultivated here which had a THC level of 16 per cent.

“In the context of the recent findings from the 2010/11 Drug Prevalence Survey that cannabis remains the most commonly used illicit drug in Ireland, monitoring the potency of available cannabis is extremely important,’ Dr Corrigan added.

Read the report from the NACD in full >

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