Aucklanders like their methamphetamine, but not as much as they do in Adelaide, a new study has found.
Researchers at the University of South Australia have looked at illicit drugs in the wastewater systems across cities in 37 countries, including Auckland, and found meth is popular in western Europe, North America and Australasia, while other drugs - such as cocaine and ecstasy - dominate elsewhere.
"Determining the scale of the illicit drug market... is an important but challenging task for law and drug enforcement agencies to assess the efficacy of drug‐related policy and control/prevention measures," their study, published Thursday in the journal Addiction, says.
"Historically, this has been established through a combination of seizures, surveys, drug treatment demands, drug‐related hospital admissions and arrest data."
Recently scientists have been turning to wastewater to track drug use. A study carried out by researchers from University of Queensland and Massey University in 2017 found Aucklanders use meth to get through the working week, but turn to cocaine and ecstasy when the weekend arrives.
The latest study looked at not just Auckland, but cities across Europe, Australasia and the Americas between 2011 and 2017.
"The results showed a worrying trend of drug use across the world."
Cocaine was in big demand in London, Bristol, Amsterdam, Zurich, Geneva, St Gallen, Antwerp and South America, overall use rising by 13 percent. The drug dominates southwestern Europe too, "until the border with Belgium and Switzerland, where other drug use patterns start to emerge".
Heading east, amphetamine dominates in the northeast and methamphetamine in central and southeastern Europe, where large quantities are manufactured.
"The cities with the highest overall drug levels in Europe include Antwerp, Amsterdam, Zurich, London and Barcelona, while at the other end of the scale, cities in Greece, Portugal, Finland, Poland and Sweden have the lowest rates of drug use," the researchers said.
But Australasia and North America methamphetamine consumption rates are "huge, far exceeding levels in eastern Europe", the study found.
Adelaide leads the way with consumption rates above 600mg per person, per day. Seattle, Canberra, Montreal and Auckland aren't far behind. Auckland ranks inside the top half of cities looked at in the study.
Ecstasy use was highest in the Netherlands.
Cannabis use was relatively low in Auckland compared to other cities - with Amsterdam predictably far out in front, followed by the birthplace of slacker grunge music Seattle.
"It's important we determine the scale of the illicit drug market so that countries can work out the best way to tackle a $100 billion industry, which is contributing to the global burden of disease and affecting the economic development of many countries," said University of South Australia chemist Dr Richard Bade, who co-authored the study.
Auckland was the only New Zealand location included in the research.
Biggest users of each drug
- Fort−de−France (French city in the Caribbean)
- Novi Sad