This study examined the occurrence in wastewater of 11 aromatic biocides, pesticides and degradates, and their fate during passage through US treatment plants, as well as the chemical mass contained in sewage sludge (biosolids) destined for land application. Analyte concentrations in wastewater influent, effluent and sludge from 25 facilities in 18 US states were determined by liquid chromatography electrospray (tandem) mass spectrometry. Dichlorocarbanilide, fipronil, triclocarban, and triclosan were found consistently in all sample types.
View Article and Find Full Text PDFEnviron Sci Technol
September 2008
Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (phi), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale.
View Article and Find Full Text PDFThe biocides triclosan and triclocarban are wastewater contaminants whose occurrence and fate in estuarine sediments remain unexplored. We examined contaminant profiles in 137Cs/7Be-dated sediment cores taken near wastewater treatment plants in the Chesapeake Bay watershed (CB), Maryland and Jamaica Bay(JB), New York. In JB, biocide occurrences tracked the time course of biocide usage and wastewater treatment strategies employed, first appearing in the 1950s (triclocarban) and 1960s (triclosan), and peaking in the late 1960s and 1970s (24 +/- 0.
View Article and Find Full Text PDFThree organic wastewater compounds (OWCs) were evaluated in theory and practice for their potential to trace sewage-derived microbial contaminants in surface waters. The underlying hypothesis was that hydrophobic OWCs outperform caffeine as a chemical tracer, due to their sorptive association with suspended microorganisms representing particulate organic carbon (POC). Modeling from first principles (ab initio) of OWC sorption to POC under environmental conditions suggested an increasing predictive power: caffeine (0.
View Article and Find Full Text PDFBackground: Recent studies have reported blood levels of polybrominated diphenyl ethers (PBDEs) in the U.S. population.
View Article and Find Full Text PDFPolyfluoroalkyl compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), are ubiquitous, man-made chemicals. Human data suggest that in utero exposures to these chemicals occur and some evidence of developmental toxicity in animals exists. To assess the distribution and determinants of fetal exposure to PFCs, we analyzed cord serum samples from 299 singleton newborns delivered between 2004 and 2005 in Baltimore, MD for 10 PFCs by employing on-line solid-phase extraction coupled with reversed-phase high-performance liquid chromatography-tandem mass spectrometry.
View Article and Find Full Text PDFThe topical antiseptic agent triclocarban (TCC) is a common additive in many antimicrobial household consumables, including soaps and other personal care products. Long-term usage of the mass-produced compound and a lack of understanding of its fate during sewage treatment motivated the present mass balance analysis conducted at a typical U.S.
View Article and Find Full Text PDFThe antimicrobial agent triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol; TCS) is a member of a larger group of polychlorinated binuclear aromatic compounds frequently associated with adverse environmental and human health effects. Whereas the structure and function of TCS would suggest significant resistance to biotransformation, biological wastewater treatment currently is considered the principal destructive mechanism limiting dispersal of and environmental contamination with this compound. We explored the persistence of TCS in a typical full-scale activated sludge US sewage treatment plant using a mass balance approach in conjunction with isotope dilution liquid chromatography electrospray ionization mass spectrometry (ID-LC-ESI-MS) for accurate quantification.
View Article and Find Full Text PDFThe antimicrobial compound triclocarban (TCC; 3,4,4'-trichlorocarbanilide; CAS# 101-20-2) is a high-production-volume chemical, recently suggested to cause widespread contamination of US water resources. To test this hypothesis, we developed an isotope dilution liquid chromatography electrospray ionization tandem mass spectrometry method for ultratrace analysis of TCC (0.9 ng/L detection limit) and analyzed low-volume water samples (200 mL) along with primary sludge samples from across the United States.
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