posted on 2021-03-08, 19:05authored byRachele Ossola, Oskar Martin Jönsson, Kyle Moor, Kristopher McNeill
Singlet oxygen (1O2) is a reactive oxygen
species produced in sunlit waters via energy transfer from the triplet
states of natural sensitizers. There has been an increasing interest in measuring apparent 1O2 quantum yields (ΦΔ) of aquatic
and atmospheric organic matter samples, driven in part by the fact
that this parameter can be used for environmental fate modeling of
organic contaminants and to advance our understanding of dissolved
organic matter photophysics. However, the lack of reproducibility
across research groups and publications remains a challenge that significantly
limits the usability of literature data. In the first part of this
review, we critically evaluate the experimental techniques that have
been used to determine ΦΔ values of natural
organic matter, we identify and quantify sources of errors that potentially
explain the large variability in the literature, and we provide general
experimental recommendations for future studies. In the second part,
we provide a qualitative overview of known ΦΔ trends as a function of organic matter type, isolation and extraction
procedures, bulk water chemistry parameters, molecular and spectroscopic
organic matter features, chemical treatments, wavelength, season,
and location. This review is supplemented with a comprehensive database
of ΦΔ values of environmental samples.