Occurrence of Alkenylbenzenes in Plants: Flavours and Possibly Toxic Plant Metabolites

Alkenylbenzenes are naturally occurring secondary plant metabolites. While some of them are proven genotoxic carcinogens, other derivatives need further evaluation to clarify their toxicological properties. Furthermore, data on the occurrence of various alkenylbenzenes in plants, and especially in food products, are still limited. In this review, we tempt to give an overview of the occurrence of potentially toxic alkenylbenzenes in essential oils and extracts from plants used for flavoring purposes of foods. A focus is layed on widely known genotoxic alkenylbenzenes, such as safrole, methyleugenol, and estragole. However, essential oils and extracts that contain other alkenylbenzenes and are also often used for flavoring purposes are considered. This review may re-raise awareness of the need for quantitative occurrence data for alkenylbenzenes in certain plants but especially in final plant food supplements, processed foods, and flavored beverages as the basis for a more reliable exposure assessment of alkenylbenzenes in the future.

Automated summary

Alkenylbenzenes are natural secondary plant metabolites, some of which are proven genotoxic carcinogens. This review provides an overview of the occurrence of potentially toxic alkenylbenzenes in essential oils and extracts used for flavoring purposes in food. It focuses on well-known genotoxic alkenylbenzenes like safrole, methyleugenol, and estragole, but also considers other alkenylbenzenes commonly used for flavoring. The review emphasizes the need for quantitative occurrence data on alkenylbenzenes in plants and final plant food supplements, processed foods, and flavored beverages for more reliable exposure assessment in the future.