In view of the toxicity and prevalence of NAs in refinery wastewater from oil sands extraction, it is imperative that a better understanding of the factors affecting their persistence in aquatic environments be developed. This need is important since factors controlling possible selective degradation of components of NAs mixtures are not established. For example, it is not known whether such factors include the diversity of various NA mixtures or whether possible differences in degradation of geometric isomers have a significant effect on their bioavailability. If a study of different NAs compounds and geometric isomers could verify such factors and differences, one would have to consider possible cumulative effects since NAs are complex mixture of hundreds of compounds.