We will propose analytical methods for measuring cationic polymers both in experimental test solutions and for environmental monitoring. Cationic polymers tend to sorb to surfaces and particulate matter. Therefore, a key focus will be on the appropriate monitoring of bioavailable concentrations. Data from the literature review will provide perspective on whether the source of organic carbon (e.g., humic acid, suspended solids, DOC, etc) has an effect on potential sorption of cationic polymers. The initial targets will be the model compounds polyquaterniums 6, 7, 10 and 16, however, other targets will also be considered in light of the data review. A variety of different dilution waters are commonly used in standard and modified ecotoxicity testing (i.e., OECD dilution water, tap water, tap water supplemented with humic acids, or river water).
We will provide recommendations on methods for the appropriate monitoring of bioavailable concentrations, and discuss proposition of mitigation factors to be used when deriving classification from tests run with well-characterized river water or organic carbon amendments. How mitigation factors would be used when deriving a PNECaqua from standard relevant OECD test guidelines will also be discussed.
