The use of hop extract dates back to ancient history when hop was known mainly for its calming effects. Nowadays, hop extract is used in the brewing industry, pharmacy, and cosmetics industry. Containing ingredients enable a wide area of hops usage, which has numerous positive effects. In addition to all positive characteristics, there are limits to the safe usage of vegetable extracts. When using vegetable extracts in cosmetic products, it is important to study particular compounds of vegetables and thus establish those safe limits. As part of the Diploma Thesis, the compounds that can be found in the hops plant and extract, were studied. Using the literature, the most common plant constituents were found. Using the ChemDraw software, the physicochemical characteristics of compounds were calculated; and those were the basis of our calculation. Combined with data on concentrations in which they can be found in plants, the safety assessment was conducted using the threshold of toxicological concern approach (TTC). TTC approach is based on the classification of compounds into three different Crammer’s classes, with low, medium, or high toxicity. The computer program Toxtree was used for classification of compounds into Cramer’s classes. Using the method, described by Kroes et al. (2007), we used the assessed maximal rate of compound diffusion through the skin and assessed the potential extent of compound absorption in 24 hours. Most compounds in hops have low or medium extent of potential absorption, but in some cases also potential for high extent of absorption. We then determined potential system exposure to all compounds and discovered that alpha and beta acids, δ-cadinene, terpineol, limonene oxid, linalool, myrcenol, and naringenin exceeded the exposure limits of their corresponding Cramer’s classes. Based on some studies in which the toxic effects of those compounds were not found, although they were used in much higher concentrations as represented by Cramer’s classification, it has been presumed that the extract is safe since the TTC values are substantially low. Moreover, the low limits of Cramer’s classes are confirmed based on NOAEL values, which are determined in animal experiments. From the NOAEL values, the safe daily dose was determined; those daily doses were much higher than comparable TTC values. Based on all the calculations and literary data, it was confirmed that the hops extract is safe for use.
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