**3. Aspects Impeding the Evaluation of Adverse Health Effects of Alkenylbenzenes** *3.1. Uncertainties Regarding the Occurrence of Alkenylbenzenes*

Adequate and comparable occurrence data are of high importance in order to estimate oral exposure of humans to certain alkenylbenzenes via consumption of foods containing these substances. Currently, there are several issues, which make it difficult to perform such a reliable oral exposure assessment of consumers for alkenylbenzenes. These aspects will be discussed in the following parts of the text.
