Marijuana Policy Project

A study conducted at the University of Mississippi revealed the levels of tetrahydracannibinol (T.H.C.) in marijuana have reached a 30-year high, almost double the reading taken in 1983, according to a press release published Thursday from the Office of National Drug Control Policy.

The study was conducted as part of a marijuana potency monitoring project and evaluated seized batches of marijuana from 48 states.

The results of the study released in March were based on measurements on 62,797 cannabis samples, 1,302 hashish samples, and 468 hash oil samples that had been seized by law enforcement agencies since 1975.

"Thirty-three percent of the cannabis samples are from domestic seizures representing all 50 states," the study reported.

The highest concentration of T.H.C. found among the samples was 37.2 percent.

The report's findings include a graph which shows the steady climb of the percentage of T.H.C. in marijuana since 1990, with the highest jump between 2007 and 2008.

This jump in potency causes alarm in drug officials.

"The increases in marijuana potency are of concern since they increase the likelihood of acute toxicity, including mental impairment," said Nora Volkow, director of the National Institute on Drug Abuse.

"Particularly worrisome is the possibility that the more potent T.H.C. might be more effective at triggering the changes in the brain that can lead to addiction.

"However, more research is needed to establish this link between higher T.H.C. potency and higher addiction risk."

"Baby boomer parents who still think marijuana is a harmless substance need to look at the facts," John Walters, director of the Office of National Drug Control Policy (O.N.D.C.P.), said in a press release.

"Marijuana potency has grown steeply over the past decade with serious implications in particular for young people, who may be not only at increased risk for various psychological conditions, cognitive deficits and respiratory problems, but are also at a significantly higher risk for developing dependency on other drugs, such as cocaine and heroin than are non-smokers."

The O.N.D.C.P. released another study in May entitled, "Teen Marijuana Use Worsens Depression: An Analysis of Recent Data Shows."

This study found teens who have been diagnosed with depression in the past year are twice as likely to use marijuana compared to those who have not.

The study also reported those who use marijuana were twice as likely to have suicidal thoughts.

The effects, however, were not always short-term.

The report cited marijuana use increases the risk of developing mental disorders by 40 percent.

Research that yields such results — paired with an ever-increasing potency — could signal the beginnings of a darker trend in the American youth culture.

"Today's report makes it more important than ever that we get past outdated, anachronistic views of marijuana," Walters was quoted as saying in an Associated Press article.