Health concerns about pesticide and herbicide contamination of smoked marijuana go back a long time. The use of paraquat, banned from national forests in 1983 because of environmental concerns, was given the go-ahead to be sprayed for marijuana eradication on private property, but not on public lands, as early as 1988.
The debate over herbicide and pesticide contamination of legal marijuana, however, began in 2012. During that year, the State of Colorado found that cannabis was being grown with pesticides, but could not receive guidance from the federal government due to marijuana’s federal illegality. With growers voicing fierce opposition to any changes to the decontamination process for removing pesticide residues, the state gave inspections a low priority. The status quo has remained in Colorado ever since.
Entrepreneurs have come to bear the brunt of that market, as some choose to invest into pesticide
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