(CN) - Overdoses stemming from heroin and painkiller abuse are now the leading cause of fatal injuries in the United States, surpassing even firearms and motor vehicle accidents, a Drug Enforcement Administration assessment reveals.
The DEA's 2015 National Drug Threat Assessment, released Thursday, also found that Mexican drug cartels are "the biggest criminal threat in the United States" and the nation's primary suppliers of marijuana, heroin, cocaine and methamphetamine.
The threat assessment revealed that more than 46,000 Americans died of drug overdoses in 2013.
Half of those deaths were caused by the abuse of heroin or prescription painkillers, according to Chuck Rosenberg, the acting administrator of the DEA.
"Sadly, this report confirms what we've known for some time," Rosenberg said. "Drug abuse is ending too many lives while destroying families and communities."
To combat this problem, Rosenberg advocated "teaching young people at an even earlier age" about the dangers of drug abuse.
"Law enforcement must continue to have the tools it needs to attack criminal groups who facilitate drug addiction," he added. "More Americans need treatment options so they can move forward living drug-free lives."
The threat assessment also found that Mexican drug cartels, in addition to causing extreme violence and attacking public officials and civilians, are causing unrest in the United States.
"Violent gangs are increasingly a threat to the safety and security of our communities," the DEA reported. "They profit by buying drugs from regional Mexican criminal affiliates and then supply American streets with these dangerous drugs, particularly heroin.
China is another source of drugs that "wreak havoc in the United States," the agency found. According to the assessment, profits from the sale of synthetic designer drugs from China make their way to Middle Eastern nations such as Syria, Jordan, Lebanon and Yemen.
More than 700 heroin deaths have been caused by the addition of fentanyl to the batch without the user's knowledge. Fentanyl is a synthetic opioid that is between 25 and 40 times more potent than heroin.
The National Drug Threat Assessment is available at www.dea.gov.
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