Wisconsin: bomb squad detonates sample of acid

It's not often that a bomb squad is asked to help clean up a pharmacy.

But experts say 2-ounces (56.7 grams) of picric acid in the basement of a drug store packed the punch of nearly half a stick of dynamite.

Store employees found the sample as they were cleaning out old chemicals. Store owner Nick Sharrow is relieved that the local bomb squad safely destroyed the sample Friday.

"This is very similar to TNT," he said.

Picric acid is not volatile as a liquid. But as it ages, it can form highly explosive crystals, Sharrow said. The sample discovered on the basement shelf dated back to around World War I.

Picric acid was used as an antiseptic and in medical formulations to treat malaria, herpes and smallpox.

The drug store and apartments above were evacuated and the street closed to traffic during the removal.