A workplace drug testing company is sounding the alarm, with meth showing up disproportionately in results nationwide

The Drug Detection Agency's data from March finds meth's turned up in a quarter of all results.

It follows the Drug Trends Survey revealing gangs are behind one-in-three sales of methamphetamine across the country.

CEO Glenn Dobson says it's no longer just a big-city issue.

He says it's in metro and rural areas alike, with the worst affected area in the Central North Island having meth show up in 30 percent of results.