The use of hemp (Cannabis Sativa L.) and hemp extracts in cosmetic products is increasingly common. While there are over 700 known varieties of cannabis, it is most commonly classified into subspecies based on the content of the psychoactive cannabinoid Δ9-tetrahydrocannabinol, where hemp contains less than 0.3 % and indica contains more than 0.3 %. The aim of this thesis is to assess the safety of a hemp extract with a high content of cannabidiol (CBD). Supercritical carbon dioxide extraction is a frequently explored method for obtaining hemp extract and was also used to obtain the extract of the hemp cultivar Helena that we studied. The safety of the extract as a cosmetic ingredient was assessed using the threshold of toxicological concern (TTC) approach based on categorising compounds according to their chemical structure into three Cramer classes of toxicity. We used ChemDraw to plot the chemical structures of the extract compounds and to obtain the values of certain physicochemical parameters (logP, logS, molecular weight). These were required for the calculations used to assess the safety of the extract. Next, Toxtree was used to categorise the compounds into Cramer classes, each with its own TTC value. Based on the calculated rate of diffusion of each compound through the skin, we estimated the potential extent of their absorption and calculated the systemic exposure. Finally, the values obtained using the TTC approach were compared with the calculated safe daily dose based on experimentally derived NOAEL values (the highest dose at which no adverse effects occur) from the literature. We found that the TTC values for each Cramer class were much lower than the safe daily exposure values. Of all the compounds in the studied extract, only one compound, namely CBD, exceeded the TTC value assigned to the Cramer class into which the compound is classified. However, this value was still significantly lower than the safe daily dose. We therefore concluded that the studied extract is safe for use as a cosmetic ingredient.
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