Residual solvents in hemp production
Hemp products are increasing in popularity due to their many positive effects. Certain safety aspects of these products should not be disregarded, even though, according to the Medicines Act, they are not pharmaceutical products.
A frequently forgotten issue is the residual solvents. Both the European and the American pharmaceutical companies provide exact guidelines for this issue. Residual solvents are divided into three groups:
- Group 1 are substances that should be avoided if possible
- Group 2 solvents can have serious health consequences, even in small quantities. The daily dose should not exceed 0.1mg.
- Group 3 substances should be controlled. A dose of more than 50mg per day should not be exceeded.
The following table provides an overview of many common solvents and their classification.
Benzene | Group 1 | Acetonitrile | Group 2 | Acetic acid | Group 3 |
Carbon tetrachloride | Group 1 | Chlorobenzene | Group 2 | Acetone | Group 3 |
1,2-Dichloroethane | Group 1 | Chloroform | Group 2 | Anisole | Group 3 |
1,1-Dichloroethene | Group 1 | Cyclohexane | Group 2 | Butanol | Group 3 |
1,1,1-Trichloroethane | Group 1 | 1,2-Dichloroethene | Group 2 | Dimethyl sulfoxide | Group 3 |
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| 1,2-Dimethoxyethane | Group 2 | Ethanol | Group 3 |
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| Ethylene glycol | Group 2 | Ethyl acetate | Group 3 |
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| Formamide | Group 2 | Ethyl ether | Group 3 |
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| Hexane | Group 2 | Ethyl formate | Group 3 |
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| Methanol | Group 2 | Formic acid | Group 3 |
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| Methylbutylketone | Group 2 | Heptane | Group 3 |
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| Methylcyclohexane | Group 2 | Isobutyl acetate | Group 3 |
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| Methylene chloride | Group 2 | Isopropyl acetate | Group 3 |
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| N-Methylpyrrolidone | Group 2 | Methylethylketone | Group 3 |
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| Nitromethane | Group 2 | Methyl isobutyl ketone | Group 3 |
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| Pyridine | Group 2 | 2-Methyl-1-propanol | Group 3 |
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| Sulfolane | Group 2 | Pentane | Group 3 |
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| Tetrahydrofuran | Group 2 | Pentanol | Group 3 |
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| Toluene | Group 2 | Propyl acetate | Group 3 |
Residual solvents testing should always be carried out if solvents from group 1 or 2 are used. Even if only solvents from group 3 is used, there is the possibility of contamination from a group 2 substance. For example, methanol in ethanol products.
A test for residual solvents can generally be of interest, to find out what is really in the product.
For example, here is a small section of the group 3 substances present in a CBD oil, which is available on the market.
The instrumentation at Reference Analytics not only allows a very reliable quantification, but also a quick and reliable screening which can be carried out with the use of a mass spectrometer. You can therefore be sure that you have no potentially toxic contaminants in your product.
We offer these tests both for purely informative reasons as well as in a fully validated setting in order to meet all client requirements.
If you have any questions regarding this type of analysis, we are happy to assist you with our expertise.
