ENVIRONMENTAL-EFFECTS OF SODIUM ACETATE FORMATE DEICER, ICE SHEAR(TM)/

The environmental impacts of Ice Shea(TM), an alternative highway deic er, have been evaluated using standard laboratory tests; biochemical o xygen demand (BOD) tests, chemical oxygen demand (COD) tests, acute ra inbow trout bioassays, and phytotoxicity tests were used. Ice Shear co nsists of equimolar sodium acetate and sodium formate. The organic mat ter of the deicer can be readily degraded microbiologically in the nat ural environment with a slow rate of degradation at lower temperatures but an increased rate at higher temperatures. At elevated temperature s, highway runoffs of the deicer may reduce the level of dissolved oxy gen in the receiving waters to cause an adverse impact. However, the a pparent activation energy calculated for the BOD rate of Ice Shear is low (8.78 kcal mole(-1)), indicating that the temperature variation ma y not significantly influence the biodegradation of the deicer compoun d. Ice Shear appears relatively harmless to aquatic animals, showing a high 96-h LC50 value (16.1 g/L) derived for rainbow trout (Oncorhynch us mykiss). Ice Shear causes minimal toxicity to representative roadsi de vegetation; herbaceous (e.g., sunflowers, beans, and lettuce) and w oody (e.g., pine seedlings) plants. Rather, the deicer at low concentr ations (less than 2 g/kg soil) seems to work as a fertilizer, promotin g the yield of biomass. The test results indicate that Ice Shear poses minimal environmental disturbance in both aquatic and terrestrial eco systems.