Illegal Drugs

Outlawing more than a dozen cannabinoids — chemicals concocted in labs and sprayed on leaves to create this risky street drug — hasn't stopped the problem. Chemists just make new versions.

The rise of legal marijuana seems to be fueling a spike in the number of pets that become unhappily high off of pilfered treats. The dose is rarely fatal, but it can be a buzzkill.

The yeast produce only tiny amounts of the drug. But eventually, the technology could lead to better painkillers and other medicines. Drug officials worry the microbes could fall into the wrong hands.

Dr. Leana Wen came to Baltimore as health commissioner to combat the city's longstanding problems with violence, drug addiction and health disparities. She finds that solutions don't come easy.

All told, more than half a million Americans used heroin in 2013, according to the Centers for Disease Control and Prevention. That represents a nearly 150 percent increase since 2007.

The residue from meth labs can cause health problems, but people aren't always told that the house they're buying is contaminated. An Indiana law requires disclosure but not mandatory testing.