The first method to quantify hydroxyl radical employed here uses dimethyl sulfoxide (DMSO) that reacts with a hydroxyl radical to yield methane sulfinic acid and a methyl radical. Several hydroxyl radical quantification techniques focus on the quantification of methane sulfinic acid or the subsequent products methane sulfonic acid and sulfate anions. Use of methane sulfinic acid or methane sulfonic acid is limited in applicability due to the presence of multiple byproducts.