Pesticides in cannabis: A review of analytical and toxicological considerations.

A review of the literature surrounding the use, analysis and detection of pesticide material for cannabis cultivation is presented. The use of pesticides in crop cultivation is not new, and cannabis crops are no exception. Studies have found that the use of these are common and that high levels of the pesticides are transferred into the cannabis smoke. The most common pesticides classes associated with cannabis are insecticides, acaricides and fungicides. Over 350 different pesticide products may be used on cannabis materials and of these, 16 pesticides and 3 plant growth regulators (PGR) are considered to be the main candidates. Many of the pesticides found in cannabis samples destined for consumption are classed as moderately hazardous by the World Health Organisation. Analytical methods for pesticide detection on cannabis are being developed with a view to implement quality control to cannabis where it is legal before being sold. However, no standardised protocol exists. The pesticide levels found in the cannabis samples tested were generally low (less than μg·g^-1 ), these results do not however provide information on chronic low-dose adverse effects of pesticides in relation to cannabis consumption. Currently no research exists on the toxicity of pyrolysed pesticides in humans from smoking cannabis. More studies are needed to further understand this potentially harmful health threat.