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Cannabis contaminants

Cannabis contaminanten


Traces of pesticides were found in cannabis samples (nederwiet) from different coffee shops in the Netherlands. The levels are very low and of no consequence to the users' health. This applies to the samples used as a tea or smoked. Aflatoxines produced by fungi commonly found on plants were not found.

In this exploratory study, RIVM analysed nederwiet samples from 25 coffee shops for the presence of contaminants, specifically aflatoxines and residues of pesticides.

This study was commissioned by the Ministry of Health, Wellfare and Sports. It is important that cannabis does not contain significant levels of pesticides because it may harm the user, particularly when already in poor health. This is relevant because people that take cannabis for medical reasons do not always turn to a pharmacy. Only the cannabis available at pharmacies (mediwiet) is produced under quality conditions.

In 23 of the 25 samples one or more pesticides were identified. In 11 samples the observed levels exceed the limits set for herbal medicines. One sample contained a banned pesticide but at a level that is of no consequence to the users' health.

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