Ohio Sen. Rob Portman has been busy in Washington touting the Comprehensive Addiction Recovery Act in response to a shocking number of heroin overdoses in Ohio.

The bill just passed in the Senate, 94-1. (Nebraska Sen. Ben Sasse was the sole "nay," saying he believes that fighting addiction is a local issue.)

Ohio ranks high on the list of states reeling from the national epidemic. In Montgomery County, which encompasses Dayton, Ohio, heroin-related deaths increased 225 percent between 2011 and 2015.

Back in the 1970s, the heroin on U.S. streets was the "black tar" variety, and much of it came from southeast Asia. In 2010, 80 percent of the heroin in the world came from poppy fields in Afghanistan, according to the Office of National Drug Control Policy.

So when Portman said that most of the heroin in America comes from Mexico’s border, we were skeptical.

Portman, it turns out, has done his homework. The Drug Enforcement Administration’s National Drug Threat Assessment of 2015 says that Mexico is the primary supplier of heroin to the United States.

"Southeast Asia was once the dominant supplier of heroin in the United States, but Southeast Asian heroin is now rarely detected in U.S. markets," the report state. "Mexico and, to a lesser extent, Colombia dominate the U.S. heroin market, because of their proximity, established transportation and distribution infrastructure, and ability to satisfy U.S. heroin demand."

The report also says that Mexican "transnational criminal organizations," (the DEA’s term for drug-dealing gangs) "pose the greatest criminal drug threat to the United States; no other group is currently positioned to challenge them."

The National Drug Threat report notes that Colombian gangs were traditionally the suppliers of wholesale cocaine and heroin to Mexican and Dominican groups. But cartels in Mexico are ramping up their roles on the supply side -- opium production in Mexico increased by 50 percent in 2014.

Mexican labs also produce fentanyl, a synthetic painkiller that is 80 to 100 times stronger than morphine. Fentanyl is sometimes mixed with heroin or substituted for heroin, and the DEA reports more than 700 overdoses attributed to fentanyl between late 2013 and early 2015.

Drugs get past the U.S. borders mostly "by land, not by sea," said Homeland Security Secretary Jeh Johnson, in the same March 8 hearing with Portman. And a 2015 Washington Post series on the surge of heroin puts the border detection rate at a scant 1.5 percent.

Smugglers’ creativity defies gravity: One successful bust came when agents caught two men flying a drone carrying 28 pounds of heroin from Mexico to California.

Our ruling

Portman said that heroin is coming to the United States primarily from Mexico. He hasn’t been studying drug facts for nothing.

We rate this claim True.