Acute Fish Toxicity and Absorption Tests of an Experimental Detergent Builder, Trisodium Carboxymethyloxysuccinate

Abstract

Trisodium carboxymethyloxysuccinate (NaCMOS) is a new sequestering agent being evaluated as a builder in detergents. It contains neither phosphorus nor nitrogen and is readily and completely biodegraded in aerobic and anaerobic environments. The concentration of NaCMOS lethal to 50% of a batch of fish over 96 h (TLm96) in static tests is 2.9 g/litre and 2.3 g/litre for goldfish (Carassius auratus) and rainbow trout (Salmo gairdneri), respectively, in hard water (300 mg hardness/litre as calcium carbonate). These concentrations are 2300 to 160 000 times greater than the predicted concentrations that could occur in the aquatic environment from the use of NaCMOS as a detergent builder. The highly polar character of NaCMOS indicates that it would not be bioconcentrated; this is consistent with the results of absorption tests using 14C-labeled NaCMOS and goldfish. The results support the environmental acceptability of NaCMOS.