The use of marijuana is prevalent all around the world. The drug is known to create feelings of calm and reduce anxiety for users. A new study indicates that Australia may have the strongest, and potentially most dangerous, marijuana available.

Marijuana's strength is measured by its THC content, the drug's active ingredient. The level of THC has been steadily increasing in marijuana over the past 10 years. Data indicates that in America, marijuana contained an average of three percent THC in 1993, while in 2008 THC levels nearly tripled to nine percent. However, this isn't even close to the THC levels in Austrailia.

A new study by the National Drug and Alcohol Research Centre indicates that Australian marijuana is by far the strongest in the world. In measures of THC content, much of the marijuana seized from people on the streets there contains an average of 15 percent THC, and can go as high as 40 percent THC.

This study provides the first comprehensive Australian data on street-level cannabis potency, through analysis of cannabis seizures obtained from New South Wales (NSW), Australia's most populous state.

The use of such high levels of THC can force users to suffer serious adverse events. These events include seizures, dependence, and even anxiety. In fact, the use of marijuana with such high THC levels ends up undoing the drug's "therapeutic" effects.

Researchers were interested in where the Australian marijuana was grown, as location may have an effect on THC content. They found that regardless of indoor or outdoor cultivation, the marijuana coming from Australia's NSW region tended to have levels of THC that were out of control.

Experts, according to The Sydney Morning Herald, feel that more than 15 percent of THC should be considered an illicit substance as the adverse effects can be likened to the negative effects of controlled and illegal drugs like cocaine.

Thanks to Australia's marijuana strength, the country could oust Amsterdam as the world's "weed capital" — that is, until all of the incredibly strong marijuana is deemed illegal.

Source: Swift W, Wong A, Li M, Arnold JC, McGregor IS. Analysis of Cannabis Seizures in NSW, Australia: Cannabis Potency and Cannabinoid Profile. PLOS One. 2013.