Warning over higher potency of home-grown cannabis

Herbal cannabis cultivated in sophisticated grow houses across Ireland is more likely to cause psychosis than imported herb and resin, it has emerged.

Forensic tests showed skunk or weed produced from cannabis factories have higher levels of the psychoactive component tetrahydrocannabinol (THC).

Scientists at the Forensic Science Laboratory (FSL) said the home-grown drug also has low levels of the substance cannabidiol (CBD) which counteracts the effects of THC.

The National Advisory Committee on Drugs (NACD) raised serious concern about the surges in cannabis cultivation in Ireland.

Dr Des Corrigan, chairman of the NACD, said: “Many of the plants being grown here are genetically selected to ensure they produce high levels of THC but they also lack a substance called CBD, which seems to protect the brain from the effects of THC, which can include psychosis.

“Samples from seizures of the cannabis herb in Limerick, Cork, Tipperary, Bandon, Fermoy and Dublin – including Ronanstown, Dundrum, Tallaght and Crumlin - found that cannabis which was of Irish cultivation had very high THC levels and very low CBD levels compared to imported herb and resin (hash).”

Cannabis remains the most commonly used illicit drug in Ireland, but can not be grown outdoors because of Ireland’s climate.

Instead, plants are cultivated indoors using state of the art hydroponics and intensive lighting equipment.

Approximately 20,000 cannabis plants have been seized in the sophisticated grow houses nationwide in recent years, including 800 plants uncovered by gardai in Dundalk, Co Louth, yesterday.

One of the largest ever hauls of 1,500 cannabis plants was discovered in a rented house in Kyletalesha, near Portlaoise, Co Laois, in September – the same day up to 500 cannabis plants at various stages of growth were found in a sophisticated growing operation in Co Louth.

Detectives believe Irish criminal gangs are moving in to the cultivation of cannabis, which had been dominated by Asian gangs until recently.

Dr Corrigan warned that in many cases, female rather than male plants are used as they cannot then produce seeds, meaning all of the energy within the plant goes into the production of THC content, increasing the plant’s potency.

“The high quantity of THC in cannabis raises serious health concerns as recent UK studies has shown that there is a higher risk of psychosis in those who smoke high-potency cannabis products compared to those who smoke hash which contains both THC and CBD,” he added.

“While it is the high THC content and frequency of use of the former products that may cause psychotic episodes, it is also thought to be attributed to the amount or lack thereof of CBD, as CBD appears to decrease the effects of THC when ingested together.”

Independent TD Luke ``Ming'' Flanagan said the report only convinced him even further to support the legislation of cannabis.

The campaigner said regulation would control the quantity of components such as THC and CBD in the drug, as it will never happen in a criminal environment.

“Legislation would guarantee what is in it and what strength it was,” he said.

Mr Flanagan, who quit smoking cannabis in Ireland when he was elected last March, said there was a creeping reality around the world that legislation was the right way to go.

Cannabis smokers in Switzerland will soon be allowed to grow up to four marijuana plants, while it can be sold and consumed legally in Holland. It is also legal to cultivate or smoke cannabis for your own personal use in Spain.

He said similar laws in Ireland would be a great start, but demanded outright legislation.

“It would take the €600m to €700m out of the hands of scumbags, like the type that killed Veronica Guerin,” he said.

But the TD stressed he was more concerned about anecdotal evidence he has that adulterants, such as silicone and crushed up car tyres, are being used to bulk up cannabis herb.

“The point is, people are smoking something that is killing them,” said Mr Flanagan.

“It’s very, very dangerous. I have heard reports that when the ash is rubbed between somebody’s fingers, it turns into a black, sticky, oily substance.

“We need to warn people to stay away from it.

“The only way to deal with that is to legalise it.”