Environmental fate of amine oxide: Using measured and predicted values to determine aquatic exposure.

Amine oxide (AO) surfactants are used widely in North American household detergents resulting in >44,000mtons disposed down the drain annually. Due to AOs substantial down the drain disposal volume, wide dispersive use, and high aquatic toxicity, there is a need to evaluate ecological exposure and corresponding risk. This study refined the current knowledge regarding the fate of AO disposed down the drain through laboratory simulation studies to evaluate biodegradation in the sewer and during activated sludge wastewater treatment.

Assessing the biodegradability of microparticles disposed down the drain.

Microparticles made from naturally occurring materials or biodegradable plastics such as poly(3-hydroxy butyrate)-co-(3-hydroxy valerate), PHBV, are being evaluated as alternatives to microplastics in personal care product applications but limited data is available on their ultimate biodegradability (mineralization) in down the drain environmental compartments. An OECD 301B Ready Biodegradation Test was used to quantify ultimate biodegradability of microparticles made of PHBV foam, jojoba wax, beeswax, rice bran wax, stearyl stearate, blueberry seeds and walnut shells. PHBV polymer was ready biodegradable reaching 65.

Evaluation of anionic surfactant concentrations in US effluents and probabilistic determination of their combined ecological risk in mixing zones.

Alcohol sulfates (AS), alcohol ethoxysulfates (AES), linear alkyl benzenesulfonates (LAS) and methyl ester sulfonates (MES) are anionic surfactants that are widely used in household detergents and consumer products resulting in over 1 million tons being disposed of down the drain annually in the US. A monitoring campaign was conducted which collected grab effluent samples from 44 wastewater treatment plants (WWTPs) across the US to generate statistical distributions of effluent concentrations for anionic surfactants. The mean concentrations for AS, AES, LAS and MES were 5.

Determination of biodegradation rates for surfactants and a fatty alcohol in aerobic sediment using a simplified test system.

The development of specific regulatory persistence criteria and a growing need to conduct risk assessments in sediment have increased the need to better understand fate in this compartment. A simplified test approach was developed to assess the fate of chemicals in aerobic sediments and used to evaluate the biodegradation of (14) C-labeled representative analogs of alcohol sulfate, alcohol ethoxylate, alcohol ethoxy sulfate, linear alkylbenzene sulfonate, and tetradecanol in 2 different sediments. The method provides kinetic data on primary and ultimate biodegradation in sediments as well as information on biodegradation pathways and metabolites.

Widespread Microbial Adaptation to l-Glutamate-N,N-diacetate (L-GLDA) Following Its Market Introduction in a Consumer Cleaning Product.

l-Glutamate-N,N-diacetate (L-GLDA) was recently introduced in the United States (U.S.) market as a phosphate replacement in automatic dishwashing detergents (ADW).

Fate of free and linear alcohol-ethoxylate-derived fatty alcohols in activated sludge.

Pure homologues of [1-14C] C12, C14, and C16 alcohols and the linear alcohol ethoxylates, AE [1-14C alkyl] C13E9 and C16E9 were tested in a batch-activated sludge die-away system to assess their biodegradation kinetics and to predict levels of free alcohol derived from AE biodegradation in treated effluent. First-order rates for primary biodegradation were similar for all alcohols (86-113 h(-1)) and were used to predict removal under typical treatment conditions. Predicted removals of fatty alcohols ranged from 99.

Effect of ethoxylate number and alkyl chain length on the pathway and kinetics of linear alcohol ethoxylate biodegradation in activated sludge.

Batch activated-sludge die-away studies were conducted with various pure homologs to determine the effect of ethoxylate number and alkyl chain length on the kinetics of primary and ultimate biodegradation of linear alcohol ethoxylates. The 14C-(ethoxylate) homologs C14E1, C14E3, C14E6, and C14E9 were used to investigate the effect of ethoxylate number, and 14C-(ethoxylate) homologs C12E6, C14E6, and C16E6 were used to examine the effect of chain length. Activated sludge was dosed with a trace concentration (0.