Radiolytic studies of naphthalene in the presence of water.

Naphthalene is an interesting candidate to study in the framework of organic delivery to planetary surfaces as well as in the origin of life. Additionally, naphthalene is of environmental interest, because of its chronic and acute effects on living systems, such as humans and animals (e.g. moths). Naphthalene has been well studied in both fields. In this paper we give an overview of radiolytic studies of naphthalene in the presence of both liquid water and water ice. From our review it appears that OH radicals are formed both in liquid water and in interstellar ices and that these radicals play a considerable role in the degradation of naphthalene. However, it also appears that upon irradiation of naphthalene in liquid water, hydrogen peroxide, a species that accelerates naphthalene degradation, is formed. Based on this review we suggest that the role of hydrogen peroxide in interstellar ices should be further investigated.