Microbial degradation of petroleum hydrocarbons: an environmental perspective.

The environmental fate of phthalate esters: A literature review

Nonylphenol in the environment: A critical review on occurrence, fate, toxicity and treatment in wastewaters

Triclocarban (TCC) and triclosan (TCS) are antimicrobial additives in personal care products. Whereas TCS has been studied extensively, the environmental fate of TCC remains largely unknown. To address this data gap, we performed quantitative structure-activity relationship (QSAR) analyses that suggested a propensity of TCC to persist in various environmental compartments with predicted half-lives ranging from 0.75 days in air to 540 days in sediment. Moreover, concentrations of both antimicrobials were measured in 42 environmental samples from the Greater Baltimore region using a combination of solid-phase extraction, liquid chromatography/mass spectrometry, and isotope dilution. The co-occurrence of TCC and TCS was observed, owing to similar properties, usage, disposal, and environmental half-lives. A linear empirical correlation (R2 = 0.9882) fit the log-log-transformed data from diverse aquatic media and spanned 5 orders of magnitude in concentration. Occurrences of TCC predicted for 85 U.S. streams were statistically indistinguishable from experimental regional data (alpha < or = 0.05). Annual loading of antimicrobials to water resources probably is dominated by activated sludge treatment plants (39-67%), followed by trickling filters (31-54%) and combined and sanitary sewer overflows (2-7% and <0.2%, respectively). Study results suggest that TCC is a previously unrecognized contaminant of U.S. water resources nationwide, likely ranking in the top 10 in occurrence rate and in the top 20 in maximum concentration among 96 organic pollutants considered. The magnitude and frequency of TCC contamination (regional, 6750 ng/L, 68%; predicted nationwide for 1999--2000, 1150 ng/L, 60%) were markedly higher than non-peer-reviewed numbers (240 ng/L, 30%, U.S.) currently used by the U.S. Environmental Protection Agency for evaluating TCC's ecological and human health risks.

Co-occurrence of triclocarban and triclosan in U.S. water resources.

Phthalate esters in the environment: A critical review of their occurrence, biodegradation, and removal during wastewater treatment processes.

~ ., . (7) Strup, P. E., Giammar. R. D., Stanford, T. B., Jones, P. W., in “Carcinogenesis--A Comprehensive Survey”, Freudenthal. R. I., (1958). (12) Xau. C. A,, Neal, J.. Stembridge, V., Arch. Ind. Hyg . , 20, 512 ,Jones. P.:Eds., Raven Press, New York, 1976, pp 241-51. (8) Nau, C. A,, paper presented at the Conference on Environmental Aspects of Chemical Use in Rubber Processing Operations, Akron, Ohio, March 12-~14, 1975. (9) Neal, J., Thornton, M., Nau. C. A,, Arch. Enuiron. Health, 4,46 (1962). 1979. (1960).

An environmental safety assessment of butyl benzyl phthalate.

Les limites de detection pour les alkylbenzenesulfonates lineaires (LAS) et les dialkyltetralinesulfonate (DATS) dans l'eau sont d'environ 0,001 mg/L; dans les sediments elles sont de 0,5 mg/kg pour LAS et de 0,2 mg/kg pour DTAS respectivement

Determination of linear alkylbenzenesulfonates and dialkyltetralinsulfonates in water and sediment by gas chromatography/mass spectrometry

The ultimate biodegradation of the commercial products nonylphenol ethoxylates (NPE9), octylphenol ethoxylates (OPE9), and their biodegradation intermediates, NPE1.5, OPE1.5, NP, and OP, was measured using conventional methods. The extent of biodegradation was also determined by gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) analysis of metabolites and measurement of dissolved organic carbon. Optimized pseudo-first order degradation rate constants and half-lives were calculated from these data and from previously published data, using Larson's equation for surfactant degradation kinetics. Ultimate aerobic biodegradation of alkylphenol ethoxylates and their biodegradation intermediates has now been examined using acclimated wastewater treatment plant sludge as the microbial seed, household wastewater treatment systems, and unacclimated fresh water, seawater, and soil. Ultimate biodegradation half-lives ranged from about one to four weeks and provide definitive evidence for the extensive biodegradability of alkyphenol ethoxylates (APE) surfactants and their metabolites and their lack of persistence in the environment.

Ultimate biodegradation of alkylphenol ethoxylate surfactants and their biodegradation intermediates

Concentrations of linear alkylbenzene sulfonates (LAS), dialkyltetralin sulfonates (DATS), and their biodegradation intermediates are reported for the influents and effluents of 10 U.S. domestic wastewater treatment plants as well as upstream and downstream river waters and sediments. Three types of treatment facilities in 10 U.S. states were sampled and analyzed. Removals were calculated based on initial concentrations of LAS and DATS. A derivatization electron capture/gas chromatography/mass spectrometry method was employed. Its increased sensitivity and selectivity permitted the determination of environmental levels of LAS, DATS, and their biodegradation intermediates at low micrograms per liter (ppb) concentrations. The removal from four activated sludge and five trickling filter wastewater treatment facilities averaged 99.5% and 82.9% for LAS and 99.1% and 97.3% for LAS intermediates, respectively, for the activated sludge and trickling filter facilities. In the same plants, percent removals for DATS averaged 95% and 63.2% and DATS intermediates 59.1% and 58.7%, respectively. The removals obtained by a rotating biological contactor were similar to those observed in the activated sludge wastewater treatment facilities.

Environmental monitoring for linear alkylbenzene sulfonates, dialkyltetralin sulfonates and their biodegradation intermediates

This review article will focus on the environmental safety assessment of organic phosphonates used in water treatment and detergent application. The review will summarize use, environmental fate, persistence and aquatic toxicity.

William E. Gledhill

Papers

An environmental safety assessment of butyl benzyl phthalate.

Determination of linear alkylbenzenesulfonates and dialkyltetralinsulfonates in water and sediment by gas chromatography/mass spectrometry

Ultimate biodegradation of alkylphenol ethoxylate surfactants and their biodegradation intermediates

Environmental monitoring for linear alkylbenzene sulfonates, dialkyltetralin sulfonates and their biodegradation intermediates

Environmental Properties and Safety Assessment of Organic Phosphonates Used for Detergent and Water Treatment Applications