An Acton mum-of-six has hit out at a councillor for his call to legalise cannabis and has branded him "out of his mind."
The chair of the Conservative group in Southfield, the ward Cllr Malcolm represents, believes his comments could encourage young people to dissociate the drug with any risk.
She added: "I suppose his theory is that when our children develop a psychotic illness as a result of using it, they will have theoretically paid for their own treatment by the time they need it.
"I am absolutely certain that anyone supporting the legalise cannabis campaign in order to tax it and provide a revenue stream for the government must be out of their mind.
"As a mother, I am more than aware of the horrendous long-term effects exposure to cannabis can have on young people.
"Cannabis is an evil mood altering addictive drug, with frequent use causes severe mental health problems such as long term depression, schizophrenia and bipolar disorder, even after you have stopped using it.
"To call for legalisation of the drug without considering all of the facts is irresponsible and Cllr. Malcolm is sending the wrong message to the young people of Ealing."
Ealing's Clinical Commissioning Group has not commented on the issue.
Councillor Malcolm's call led many people to take to the internet to both agree and disagree with the proposal.
Ria Hyams, a Facebook user commenting on the Ealing Gazette page, said: "Yes. I suffer from fibromyalgia and have mental health issues, both of which can be helped by using marijuana but I won't (use it) unless it's legal.
Meanwhile another Internet user commenting on the story, under the name of Chef77, said: "I thought smoking already puts huge pressure on the NHS.
"What's next legalising heroin to pay for education."
After getwestlondon put Ms Costello's comments to Councillor Malcolm, the Sheffield University graduate responded by saying his argument was based on sufficient evidence.
He added: "As a graduate in Genetics, my scientific background leads me to form policies based on evidence.
"The incidence of psychosis is down to the ratio of THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol).
"By licencing cannabis you will massively reduce the types of cannabis that are more likely to cause phycosis.
"Doing what Vanessa says, means that she is happy to see more people have psychotic incidents.
"Regulation and the licencing of where you can buy cannabis means a safer product.
"A paper in the journal Lancet Psychiatry shows evidence that cannabis use by teenagers does not increase after American states legalised medical cannabis."