Here’s a troubling source of toxins that hasn’t made it onto the average environmentalist’s radar screen: methamphetamine labs. For every pound of the illegal stimulant produced, six pounds of toxic waste are left behind. Not surprisingly, there’s no environmental oversight for meth labs, so the toxic waste is often dumped into rivers or directly onto the ground. The waste contains benzene and phosphene gas, among other toxins, and can cause explosions, burn skin, impair mental functioning, damage lungs, and, in the worst cases, lead to brain damage and cancer. The problem is of mounting concern in Montana, where meth is the drug of choice and production is skyrocketing.