ENVIRONMENTAL FATE AND EFFECTS OF DEEDMAC - A NEW RAPIDLY BIODEGRADABLE CATIONIC SURFACTANT FOR USE IN FABRIC SOFTENERS

This paper introduces the environmental safety database for a new fabr ic softening cationic surfactant. the di-(tallow fatty acid) eater of di-2-hydroxyethyl dimethyl ammonium chloride, DEEDMAC (Diethyl Eater D imethyl Ammonium Chloride). The physiochemical properties of DEEDMAC a re similar to those for ditallow dimethyl ammonium chloride (DTDMAC), the major cationic surfactant used in fabric softener formulations wor ld-wide for over thirty years. Importantly, however, DEEDMAC differs s tructurally from DTDMAC by the inclusion of two weak ester linkages be tween the ethyl and tallow chains. These ester linkages allow DEEDMAC to be rapidly and completely biodegraded in standard laboratory screen ing tests and a range of environmental compartments. including raw sew age, activated sludge, anaerobic digestor sludge, sludge amended soil. and river waters. Removal of DEEDMAC during sewage treatment is great er than 99%, as determined by computer model predictions and confirmed by laboratory simulation testing (OECD Continuous Activated Sludge co nfirmatory test). Using estimated tonnages, per capita waste water flo ws, incidences of sewage treatment for individual countries, measured removal rates, and validated computer models, maximum river water and soil concentrations of DEEDMAC have been estimated for representative usage scenarios. Based upon these maximum predicted environmental conc entrations, acute and chronic toxicity testing of fish. invertebrates and algae, predicted aquatic safety factors range from 272 to >1000. P redicted steady state terrestrial safety factors are >1000, based on E C(50) values to earthworms and plants >50 mg/kg. The environmental saf ety database developed for DEEDMAC indicates that this cationic surfac tant is rapidly and completely biodegraded will be highly removed duri ng sewage treatment. has an ecotoxicity profile similar to broadly use d anionic and nonionic surfactants. and is environmentally safe at int ended maximum usage volumes.