Prominent CA testing lab: 84% of marijuana samples contaminated

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The cannabis industry still has a pesticide problem.

Steep Hill, one of the leading names in cannabis testing, said in a press release Wednesday that a whopping 84% of marijuana samples submitted to its Berkeley, California, lab came back positive for pesticide residues. The results were for samples tested during a 30-day period ending Oct. 10.

The residue findings include chemicals such as myclobutanil, a key ingredient in Eagle 20, a pesticide often favored by marijuana growers for its effectiveness against pests such as powdery mildew.

But Eagle 20 and other potentially toxic pesticides have become a hot-button topic in the marijuana trade in recent years, with many states enacting strict regulations regarding what types of pest controls cannabis growers are allowed to employ.

Myclobutanil – which was found in more than 65% of Steep Hill’s samples – converts into hydrogen cyanide when burned, so if such residues are present on cannabis flower that is smoked, that means consumers are inhaling potentially dangerous chemicals.

Many in the industry have begun moving away from pesticides and toward more organic methods of fighting pests, but there’s still a long way to go, as evidenced by Steep Hill’s findings.

“These results were significantly higher than expected and are cause for concern for California cannabis consumers,” Steep Hill said in the release.