Biosolids Samples Research Articles

Determination of substituted diphenylamines in environmental samples.

Owing to their stability at high temperature, low biodegradation, low water solubility, and low vapor pressure, substituted diphenylamines are used as antioxidants in rubber, foamed polymers, and as high-temperature functional fluids (e.g., lubricants, gear oils, and hydraulic fluids). There are few existing environmental measurements of these substances in any environmental medium. In this study, a method was developed for the determination of 10 substituted diphenylamines in wastewater, biosolids, and sediments using gas chromatography-tandem mass spectrometry (GC-MS/MS). The substituted diphenylamines that were measured were two styrenated diphenylamines isomers, three di-styrenated diphenylamine isomers, tert-butyl-diphenylamine, tert-octyl-diphenylamine, di-tert-butyl-diphenylamine, tert-butyl/tert-octyl-diphenylamine, and di-tert-octyl-diphenylamine. The instrument limits of detection (LODs) and limits of quantitation (LOQs) were 0.02-0.1 and 0.06-0.3ngmL-1, respectively. Target compounds were spiked into sediment, effluent water, influent water, and biosolids at the 100- and 1000-ng levels (N = 6). Analyte recoveries ranged from 71.5 to 117% with relative standard deviations (RSDs) of 2.12-12.4%. The method was applied to the analysis of influent, effluent, and biosolid samples; the sum of substituted diphenylamines were 48.1-713, 1.04-28.5ngL-1, and 85.3-1184ngg-1dw (median: 71.0, 7.30ngL-1, and 402ngg-1dw), respectively. Nine sediment samples collected in Ontario, Canada contained concentrations of the sum of substituted diphenylamines ranging from 1.55 to 897ngg-1dw.

Optimization of a microwave-assisted extraction procedure for the determination of selected alkyl, aryl, and halogenated phenols in sewage sludge and biosolids

A microwave-assisted extraction method for the determination of 15 alkyl, aryl, and halogenated phenols in sewage sludge and biosolids samples was developed and optimized. The effects of solvent, temperature, time, moisture content, acid, and number of extractions on the recovery of phenols were evaluated. Results indicated that extraction solvent had the greatest impact on the recovery of all phenols while pH had the largest effect on recovery of hexachlorophene and pentachlorophenol. Wet sludge samples were extracted with acetone-hexane mixture in the presence of glacial acetic acid. The extract was evaporated, acetylated by acetic anhydride and cleaned up by silica gel. For dry sludge samples, an optional procedure for the simultaneous extraction and acetylation of phenols was also proposed. Triclosan (TCS) and the alkyl and aryl phenols in sludge extracts were analyzed by gas chromatography-mass spectrometry (GC-MS) in electron-impact mode while polyhalogenated phenols were analyzed by GC-MS in negative ion chemical ionization mode. Method detection limits were ca. 200 ng/g for nonylphenol, <25 ng/g for TCS and other alkyl and aryl phenols, and <5 ng/g for other halogenated phenols. This method has been applied to the determination of phenolic compounds in over 150 sludge and biosolids samples since 2009.

Detection of the Antimicrobial Triclosan in Environmental Samples by Immunoassay.

A sensitive, competitive enzyme-linked immunosorbent assay (ELISA) for the detection of the antimicrobial triclosan (TCS; 2,4,4'-trichloro-2'-hydroxydiphenyl ether) was developed. Novel immunizing haptens were synthesized by derivatizing at the 4-Cl position of the TCS molecule. Compounds derived from substitutions at 4'-Cl and that replaced the 2'-OH with a Cl atom were designed as unique coating antigen haptens. Polyclonal rabbit antisera were screened against the coating antigen library to identify combinations of immunoreagents resulting in the most sensitive assays. The most sensitive assay identified was one utilizing antiserum no. 1155 and a heterologous competitive hapten, where the 2'-OH group was substituted with a Cl atom. An IC50 value and the detection range for TCS in assay buffer were 1.19 and 0.21-6.71 μg/L, respectively. The assay was selective for TCS, providing low cross-reactivity (<5%) to the major metabolites of TCS and to brominated diphenyl ether-47. A second assay utilizing a competitive hapten containing Br instead of Cl substitutions was broadly selective for both brominated and chlorinated diphenylethers. Using the most sensitive assay combination, we measured TCS concentrations in water samples following dilution. Biosolid samples were analyzed following the dilution of a simple solvent extract. The immunoassay results were similar to those determined by LC-MS/MS. This immunoassay can be used as a rapid and convenient tool to screen for human and environmental exposure.

Biosolids Samples processing for Analyses of Pathogens

In this study, a two-step approach was used to develop new sample detection and processing methods that facilitate the application of molecular techniques to uses and disposal of biosolids. In the first phase, ten methods were compared for recovering pathogens in biosolids, and the three top performing methods were selected for optimization and expanded comparison for bacteria, viruses, and helminths. The selected methods were optimized for solid-to-eluent ratio, centrifugation rate, and centrifugation time. Beef-extract based methods resulted in average recoveries ranging from 42–92% and 37–85% for E. coli and Salmonella, respectively. The range of recoveries by the glycine based method were 53–61% and 64–92% for E. coli and Salmonella, respectively. Both of these methods proved superior than the EPA methods which resulted in 29–41% and 26–40% average recoveries for E. coli and Salmonella, respectively. In the second phase, five commercially available kits were compared for removing PCR inhibitiors from sample concentrates. The Qiagen DNA purification kit was selected for integration into the new sample processing protocol which included a phenol-chloroform extraction step upstream of Qiagen cleaning. The lower limit of detection for DNA by the new method was established at between 10 and 100 nanograms in undiluted biosolid sample concentrates. The sample concentrates cleaned by our newly developed method were shown to be compatible with PCR, Real-time PCR, and a flow-through SPR biosensor technique. The new method was also successfully field tested for detecting human adenoviruses in land applied biosolids. This newly developed technique increases the applicability of PCR amplification for the detection of pathogens in biosolids. Utilization of our molecular method also offers a better classification tool for microbial pathogens (Class A and Class B) in biosolids. This title belongs to WERF Research Report Series ISBN: 9781843397779 (eBook)

Identifying and Controlling Odor in the Municipal Wastewater Environment Phase 2: Impacts of Inplant Parameters on Biosolids Odor Quality

This project was undertaken in response to needs by the wastewater treatment industry to better understand the generation of odors from biosolids produced by wastewater treatment plants (WWTPs). Its primary objective is to begin to establish relationships between WWTP process parameters and biosolids odors, so that more effective techniques for minimizing biosolids odors can be developed. The project consisted of a detailed field study involving extensive sampling and analyses at 11 WWTPs across North America with capacities from 13 to 350 million gallons per day (mgd). Biosolids samples were collected from the WWTPs at a number of sampling points, which were chosen to represent a complete snapshot of biosolids generation and handling at each WWTP. The sampling points started with influent wastewater, proceeded through primary and secondary clarification, and continued through digestion, dewatering, and onsite storage of dewatered biosolids cake. Laboratory-scale anaerobic storage tests were conducted to simulate odor development of biosolids in storage, prior to their beneficial reuse or disposal. A battery of analyses were performed on the biosolids samples by the participating utility laboratories, commercial laboratories, and specialized university laboratories. The analytical data were evaluated and compared with process and operation parameters at each participating WWTP. Results indicate that the anaerobic digestion process, including its impacts on achieving stability and minimizing odors in the final biosolids product, are not yet completely understood. A significant finding was that biosolids odors after digestion and dewatering correlate with the amount of bioavailable protein in the biosolids. Possible causes for increased bioavailable protein and increased odor generation from dewatered biosolids begin with the primary and secondary sludge handling, mixing, and liquid storage steps, and continue through the anaerobic digestion process to post-digestion processes, such as dewatering, conveyance, and cake storage. A list of future research needs was also developed based on the study findings, centered on the need for more controlled experiments that can identify and quantify the impacts of different biosolids handling and stabilization processes on biosolids odor generation. ISBN: 9781780404110 (eBook)

Characterization of the biosolids composting process by hyperspectral analysis

Composted biosolids are widely used as a soil supplement to improve soil quality. However, the application of immature or unstable compost can cause the opposite effect. To date, compost maturation determination is time consuming and cannot be done at the composting site. Hyperspectral spectroscopy was suggested as a simple tool for assessing compost maturity and quality. Nevertheless, there is still a gap in knowledge regarding several compost maturation characteristics, such as dissolved organic carbon, NO3, and NH4 contents. In addition, this approach has not yet been tested on a sample at its natural water content. Therefore, in the current study, hyperspectral analysis was employed in order to characterize the biosolids composting process as a function of composting time. This goal was achieved by correlating the reflectance spectra in the range of 400–2400nm, using the partial least squares-regression (PLS-R) model, with the chemical properties of wet and oven-dried biosolid samples. The results showed that the proposed method can be used as a reliable means to evaluate compost maturity and stability. Specifically, the PLS-R model was found to be an adequate tool to evaluate the biosolids’ total carbon and dissolved organic carbon, total nitrogen and dissolved nitrogen, and nitrate content, as well as the absorbance ratio of 254/365nm (E2/E3) and C/N ratios in the dry and wet samples. It failed, however, to predict the ammonium content in the dry samples since the ammonium evaporated during the drying process. It was found that in contrast to what is commonly assumed, the spectral analysis of the wet samples can also be successfully used to build a model for predicting the biosolids’ compost maturity.

Geotechnical characteristics of stabilised aged biosolids

Stockpiles of air-dried sludge from wastewater treatment plants, known as biosolids, are constantly increasing worldwide. This subsequently adds to the urgency of stabilising biosolids in an effort to convert them into a suitable construction material for use in engineered fills. This paper reports the result of a laboratory testing programme on biosolids stabilised with two types of waste materials, namely, bauxsol and fly ash. The biosolids collected from the Western Treatment Plant in Melbourne were stabilised in different ratios and tested to determine their compaction, strength, permeability and deformation characteristics. Both static and dynamic compaction methods were used in the preparation of the test specimens. Results suggest that the hydraulic conductivity values of biosolids consistently decrease with increasing amounts of additives, which is an indication of decreasing void ratio of material. In addition, increasing the amount of additives was found to lead to a subsequent decline in the compressibility of the stabilised biosolids. The strength of the biosolids samples increased with the addition of bauxsol and fly ash, with the highest shear strength found to be achieved with around 10% fly ash mixture. The application of stabilised biosolids in road embankments is discussed as a sustainable solution in geotechnical engineering applications.

Temporal trends of perfluoroalkyl substances in limed biosolids from a large municipal water resource recovery facility

While the recycling of wastewater biosolids via land-application is a sustainable practice for nutrient recovery and soil reclamation that has become increasingly common worldwide, concerns remain that this practice may become a source of toxic, persistent organic pollutants to the environment. This study concentrates on assessing the presence and the temporal trends of 12 perfluoroalkyl substances (PFASs), pollutants of global consequence, in limed Class B biosolids from a municipal water resource recovery facility (WRRF), also know as a wastewater treatment plant. PFASs are of significant concern due to their extensive presence and persistence in environmental and biotic samples worldwide, most notably human blood samples. Class B biosolids were collected from the WRRF, prior to land-application, approximately every two to three months, from 2005 to 2013. Overall, this study found that concentrations of the 7 detectable PFAS compounds remained unchanged over the 8-year period, a result that is consistent with other temporal studies of these compounds in sewage sludges. From these analyzed compounds, the highest mean concentrations observed over the study period were 25.1 ng/g dw, 23.5 ng/g dw, and 22.5 ng/g dw for perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), and perfluorooctanesulfonic acid (PFOS), respectively, and these compounds were detected at concentrations 2.5–5 times higher than the remaining, detectable PFASs. Furthermore, it was observed that PFOS, while demonstrating no overall change during the study, exhibited a visible spike in concentration from late 2006 to early 2007. This study indicates that concentrations of PFASs in WRRFs have been stagnant over time, despite regulation.This study also demonstrates that the use of glass jars with polytetrafluoroethylene-lined lids, a common storage method for environmental samples, will not influence PFOA and PFNA concentrations in archived biosolids samples.

Possible use of biosolids in fired-clay bricks

In Australia, thousands of tonnes of biosolids are produced annually and millions of dollars expended on their management. Biosolids are derived from wastewater sludge, which is the major solid component collected from the wastewater treatment process. This paper presents some of the results from a study concerning the use of biosolids in fired-clay bricks. The geotechnical characteristics of three biosolids samples from the stockpiles of the Eastern Treatment Plant (ETP) in Melbourne were investigated to assess their suitability as a partial replacement material for the clay in fired-clay bricks. The results of classification tests including liquid limit, plastic limit and sieve analysis indicated that the three biosolids samples were clayey sand and poorly graded silty sand. The linear shrinkage of the biosolids samples varied from 10% to 15% and the organic content varied from 6% to 14%. Control clay bricks with 0% biosolids and clay–biosolids bricks with 25% by weight of biosolids were made and the properties including the compressive strength, shrinkage, density, Initial Rate of Absorption (IRA), and water absorption were determined whereas thermal conductivity was estimated from an empirical model. Furthermore, the effect of adding biosolids on the microstructure of the fired-clay bricks was evaluated by scanning electron microscopy (SEM). The results showed that the compressive strength of clay–biosolids bricks were 25.9, 17.4 and 16.2MPa for the bricks with the three different biosolids samples used in the study. This was mainly because of the addition of biosolids samples with different organic content, which resulted in fired-bricks with higher apparent porosity and thus lower density and compressive strength. The compressive strength of the control fired-clay bricks was 36.1MPa.

Occurrence of Bisphenol A Diglycidyl Ethers (BADGEs) and Novolac Glycidyl Ethers (NOGEs) in Archived Biosolids from the U.S. EPA's Targeted National Sewage Sludge Survey.

Epoxy resins incorporating bisphenol A diglycidyl ether (BADGE) and novolac glycidyl ether (NOGE) are used in a wide range of applications, including adhesives, structural and electrical laminates. However, little is known about the occurrence of BADGE, NOGE, and their derivatives in the environment. Using liquid chromatography-tandem mass spectrometry, BADGE, bisphenol F glycidyl ether (BFDGE), 3-ring NOGE, and eight of their derivatives (BADGE·2 H2O, BADGE·H2O, BADGE·HCl·H2O, BADGE·2 HCl, BADGE·HCl, BFDGE·2 H2O, and BFDGE·2 HCl) were determined in archived biosolid samples collected from 68 wastewater treatment plants (WWTPs) from the northeastern, midwestern, western, and southern regions of the USA. BADGE·2 H2O was the most frequently detected (DR = 99%) and the most abundant compound found (median: 93.6 ng/g dry weight [dw]) in this family. The highest total concentrations of target chemicals, ranging from 83.6 to 2490 ng/g dw, were found in biosolids collected from the northeastern United States. The sum of geometric mean (GM) concentration of BADGE, NOGE, and their derivatives in biosolids increased with the treatment capacity of WWTPs. Based on the measured concentrations in biosolids and predicted mass in wastewater, it was estimated that approximately 3.5% of the total production of BADGEs was emitted through WWTP discharges.

Determining pathogen and indicator levels in class B municipal organic residuals used for land application.

Biosolids are nutrient-rich organic residuals that are currently used to amend soils for food production. Treatment requirements to inactivate pathogens for production of Class A biosolids are energy intensive. One less energy intensive alternative is to treat biosolids to Class B standards, but it could result in higher pathogen loads. Quantitative microbial risk assessments models have been developed on land application of Class B biosolids but contain many uncertainties because of limited data on specific pathogen densities and the use of fecal indicator organisms as accurate surrogates of pathogen loads. To address this gap, a 12-mo study of the levels and relationships between , , and human adenovirus (HAdV) with fecal coliform, somatic, and F-RNA coliphage levels in Class B biosolids from nine wastewater treatment plants throughout the United States was conducted. Results revealed that fecal coliform, somatic, and F-RNA coliphage densities were consistent throughout the year. More important, results revealed that HAdV ( = 2.5 × 10 genome copies dry g) and ( = 4.14 × 10 cysts dry g) were in all biosolids samples regardless of treatment processes, location, or season. oocysts were also detected (38% positive; range: 0-1.9 × 10 oocysts dry g), albeit sporadically. Positive correlations among three fecal indicator organisms and HAdV, but not protozoa, were also observed. Overall, this study reveals that high concentrations of enteric pathogens (e.g., , , and HAdV) are present in biosolids throughout the United States. Microbial densities found can further assist management and policymakers in establishing more accurate risk assessment models associated with land application of Class B biosolids.

Comparison of heavy metal content in two sludge drying reed beds of different age

The fate of heavy metals (HMs) and nutrients along the vertical profile within the sludge layer and their accumulation into reed plant (Phragmites australis) biomass from SDRBs of different running times or ages has not been well documented until now. In this study, dried biosolid samples along the vertical profile of the sludge layer (0–2, 2–10, 10–20, 20–30cm) and plant biomass samples (roots, rhizomes and aerial parts) were collected from two full-scale SDRBs of two different running times (12 years in SDRB I and 6 years in SDRB II) and their concentrations of eight HMs (Fe, Mn, Cu, Zn, Pb, Cr, Ni, Mo), organic matter and nutrient contents were analyzed. In general, total organic carbon (TOC) concentrations were found to be higher (within a range of 15–30%) in the samples of the older SDRB I (12 years) than the younger SDRB II (6 years). HMs like Fe, Mn, Cu, Zn, Pb, and Ni were predominantly accumulated within the biosolids of both SDRBs but comparatively higher concentrations were observed in the samples collected from the younger SDRB II than the samples from the older SDRB I. This clearly suggested that the longer the treatment or mineralization time, the lower might be the accumulation of HMs within the biosolids. In general, the concentrations of the HMs were increased with sludge depth, probably due to the effect of higher organic matter mineralization and dewatering. The TOC content in the biosolids from the upper layer (0–2cm) with 367.6 and 305.1gkg−1 was found to be lower in the bottom layer (20–30cm) with a concentration of 128.83 and 99.85gkg−1, which was resulted to a decreasing of concentrations by 64.9% and 67.3% in the SDRB I and SDRB II, respectively. This result suggested that the degree of mineralization process is higher or more stabilization occurs in the deeper layers as compared to the upper layer of the accumulated biosolids. Similarly, the nutrient (N, P, K, Ca, Mg, S) concentrations were found to be comparatively higher (within a range of 5–62%) within the biosolids of the younger SDRB II than the older SDRB I but decreased along the sludge depth in both SDRBs. Exceptions were the concentrations of potassium (K) and magnesium (Mg), which were increasing along the deeper layers of the biosolids from both the SDRBs. The concentrations of Fe (4760mgkg−1), Zn (688mgkg−1) and Cr (29mgkg−1) were remarkably higher in the plant matter samples collected from the older SDRB I. Comparatively much higher concentration of HMs was adsorbed or accumulated in the roots and rhizomes than translocated to the above-ground plant biomass in both SDRBs. Our results suggested that the concentrations of HMs within the accumulated biosolids of both the SDRBs were well-below the maximum permitted legal limits for agricultural land application according to the EU Sewage Sludge Directive but a higher HM uptake by the plant biomass and probable effect on their growth might be necessary to consider for future investigations.

Impact of tilling on biosolids drying and indicator microorganisms survival during solar drying process

As biosolids application to croplands becomes a common practice, potential harm from pathogenic microbes needs to be mitigated for its safe reuse. The objective of this study was to investigate the impacts of tilling treatment on biosolids drying and microbial inactivation during the solar drying process in a semi-arid and temperate region. Solar drying experiments were conducted in sand and gravel dying beds open-to-the-air and under covering structures with biosolids to 20 cm depth from 2004 to 2006. Anaerobically- and Aerobically-digested biosolids received different tilling treatments throughout the drying process, while a series of biosolids samples were collected to determine the impact on total solids and microbial concentrations (Salmonella spp and heminth ova). Tilling treatments appeared to enhance the biosolids drying and microbial inactivation. Tilling was more effective during the cold season compared with the summer season and tilling treatments were also helpful in elevating biosolids temperature by expediting biosolids drying. The combined effect of temperature increase and moisture decrease by tilling may have resulted in faster microbial inactivation, particularly for persistent helminth ova. It was concluded that incorporation of tilling into biosolids solar drying can expedite biosolids drying as well as microbial inactivation, and thus can be an effective measure for shortening the biosolids conversion to Class A biosolids in which pathogens are reduced to below detectable levels.

Long-term trends of PBDEs, triclosan, and triclocarban in biosolids from a wastewater treatment plant in the Mid-Atlantic region of the US

In the US, land application of biosolids has been utilized in government-regulated programs to recycle valuable nutrients and organic carbon that would otherwise be incinerated or buried in landfills. While many benefits have been reported, there are concerns that these practices represent a source of organic micropollutants to the environment. In this study, biosolids samples from a wastewater treatment plant in the Mid-Atlantic region of the US were collected approximately every 2 months over a 7-year period and analyzed for brominated diphenyl ethers (BDE-47, BDE-99, and BDE-209), triclosan, and triclocarban. During the collection period of 2005–2011, concentrations of the brominated diphenyl ethers BDE-47+BDE-99 decreased by 42%, triclocarban decreased by 47%, but BDE-209 and triclosan remained fairly constant. Observed reductions in contaminant concentrations could not be explained by different seasons or by volumetric changes of wastewaters arriving at the treatment plant and instead may be the result of the recent phaseout of BDE-47 and BDE-99 as well as potential reductions in the use of triclocarban.

Real scale environmental monitoring of zoonotic protozoa and helminth eggs in biosolid samples in Brazil.

Biosolid is the product of the activated sludge treatment system and its final disposition is subject of ongoing discussion as this residue can therefore harbor a great number and variety of pathogens. This study was aimed to (1) monitor the presence of Giardia and Cryptosporidium in biosolid samples from a treatment plant in Campinas, SP, Brazil, (2) observe Giardia cyst wall morphological integrity in treated samples using scanning electron microscopy (SEM) and (3) verify the presence and viability of helminth eggs. Cysts were present in 33.3% of the samples, whereas oocysts were detected in 8.3%. Viable Ascaris sp. Toxocara sp. and similar to Trichuris sp. eggs were found through the use of Mexican Official Norm. Results demonstrate the difficulties inherent in working with biosolid as factors such as temperature, ionic strength and pH influenced the recovery of cysts and oocysts. Pores and ruptures were not observed in cyst wall visualized by SEM following 45days of exposure to sunlight, only minimal morphological changes. These observations emphasize both the importance of adequate treatment of sewage sludge and the need to develop appropriate techniques for the detection of Giardia and Cryptosporidium in this type of sample. This is the first time that a study was done in a real scale for biosolid samples in determining the presence of pathogenic protozoa as Giardia and Cryptosporidium in Brazil, and also observed minimal cyst wall damage after sunlight treatment.

17 β-estradiol and 17 α-ethinylestradiol mineralization in sewage sludge and biosolids

Natural steroid estrogens (e.g., 17 β-estradiol, E2), synthetic steroid estrogens (e.g., 17 α-ethinylestradiol, EE2) and pharmaceutical antibiotics (e.g., ciprofloxacin) are chemicals detected in biosolids and sewage sludges because they partition into the solids fraction during the wastewater treatment process. This research utilized a three-way factorial design (six media × two estrogens × three antibiotic treatments) to quantify cumulative E2 and EE2 mineralization over 133 d (MAX) in a range of sewage sludge and biosolid samples in the presence (4 and 40 mg kg−1) and absence of ciprofloxacin. The same three-way factorial design was utilized to quantify the impact of the six media, E2 or EE2, and ciprofloxacin on cumulative soil respiration over 133 d (RESP). Minimal ciprofloxacin mineralization was observed (<0.05% over 133 d), but despite its persistence, ciprofloxacin had no significant effect on MAX of E2 or EE2, and, in general, no significant effect on RESP. MAX ranged from 38.38% to 48.44% for E2 but from only 0.72% to 24.27% for EE2 although RESP was relatively similar, ranging from 101.00 to 866.54 mg CO2 in the presence of E2 and from 69.55 to 893.95 mg CO2 in the presence of EE2. The sorption-limited bioavailability of EE2, which is inherently resistant to biodegradation due to chemical structure, as MAX and Freundlich sorption coefficients (Kf) were negatively correlated. As such, the Kf values of EE2 were largest in composted biosolids in which EE2 was particularly resistant to microbial degradation as the MAX of EE2 was <3%. In contrast, the MAX of E2 showed a positive association with the Kf values of E2 because some steps in the E2 transformation process have been found to occur in the sorbed phase. The MAX of E2 was significantly greater in the biosolid and composted biosolid media than in any other media, whereas the MAX of E2 decreased in the following order: secondary sewage sludge > primary sewage sludge > biosolid = composted biosolid. This suggests that sewage sludges in municipal lagoons and pre-treatment holding lagoons are a more favorable media for mineralization of EE2, whereas biosolids in post-treatment storage lagoons are a more favorable media for the mineralization of E2. The presence of ciprofloxacin will have no impact on the potential E2 or EE2 mineralization rates in these cases.

Detection and Occurrence of N-Nitrosamines in Archived Biosolids from the Targeted National Sewage Sludge Survey of the U.S. Environmental Protection Agency

The occurrence of eight carcinogenic N-nitrosamines in biosolids from 74 wastewater treatment plants (WWTPs) in the contiguous United States was investigated. Using liquid chromatography-tandem mass spectrometry, seven nitrosamines [(N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine, N-nitrosodi-n-propylamine (NDPA), N-nitrosodibutylamine, N-nitrosopyrrolidine, N-nitrosopiperidine (NPIP), and N-nitrosodiphenylamine (NDPhA)] were detected with varying detection frequency (DF) in 88% of the biosolids samples (n = 80), with five of the seven being reported here for the first time in biosolids. While rarely detected (DF 3%), NDMA was the most abundant compound at an average concentration of 504 ± 417 ng/g dry weight of biosolids. The most frequently detected nitrosamine was NDPhA (0.7—147 ng/g) with a DF of 79%, followed by NDPA (7–505 ng/g) and NPIP (51–1185 ng/g) at 21% and 11%, respectively. The DF of nitrosamines in biosolids was positively correlated with their respective n-octanol–water partition coefficients (R2 = 0.65). The DF and sum of mean concentrations of nitrosamines in biosolids increased with the treatment capacity of WWTPs. Given their frequent occurrence in nationally representative samples and the amount of U.S. biosolids being applied on land as soil amendment, this study warrants more research into the occurrence and fate of nitrosamines in biosolids-amended soils in the context of crop and drinking water safety.

Removal of pharmaceuticals and personal care products in a membrane bioreactor wastewater treatment plant.

Ninety-nine pharmaceuticals and personal care products (PPCPs) were analyzed in influent, final effluent, and biosolids samples from a wastewater treatment plant employing a membrane bioreactor (MBR). High concentrations in influent were found for acetaminophen, caffeine, metformin, 2-hydroxy-ibuprofen, paraxanthine, ibuprofen, and naproxen (10(4)-10(5) ng/L). Final effluents contained clarithromycin, metformin, atenolol, carbamazepine, and trimethoprim (>500 ng/L) at the highest concentrations, while triclosan, ciprofloxacin, norfloxacin, triclocarban, metformin, caffeine, ofloxacin, and paraxanthine were found at high concentrations in biosolids (>10(3) ng/g dry weight). PPCP removals varied from -34% to >99% and 23 PPCPs had ≥90% removal. Of the studied PPCPs, 26 compounds have been rarely or never studied in previous membrane bioreactor (MBR) investigations. The removal pathway showed that acetaminophen, 2-hydroxy-ibuprofen, naproxen, ibuprofen, codeine, metformin, enalapril, atorvastatin, caffeine, paraxanthine, and cotinine exhibited high degradation/transformation. PPCPs showing strong sorption to solids included triclocarban, triclosan, miconazole, tetracycline, 4-epitetracycline, norfloxacin, ciprofloxacin, doxycycline, paroxetine, and ofloxacin. Trimethoprim, oxycodone, clarithromycin, thiabendazole, hydrochlorothiazide, erythromycin-H2O, carbamazepine, meprobamate, and propranolol were not removed during treatment, and clarithromycin was even formed during treatment. This investigation extended our understanding of the occurrence and fate of PPCPs in an MBR process through the analysis of the largest number of compounds in an MBR study to date.

Removal of triclocarban and triclosan during municipal biosolid production.

The antimicrobial compounds triclosan (TCS) and triclocarban (TCC) accumulate in sludges produced during municipal wastewater treatment and persist through sludge treatment processes into finished biosolids. The objective of this research was to determine the extent to which conventional sludge processing systems such as aerobic digestion, anaerobic digestion, and lime stabilization were able to remove TCC and TCS. The concentrations of TCC and TCS in sludge and biosolid samples were determined via heated solvent extraction and analysis with liquid chromatography electrospray ionization mass spectrometry. The removal of TCC and TCS in municipal biosolid processing systems was determined from the measured concentration change after correcting for reductions in solid mass during sludge treatment. Removal in the digester systems ranged from 15 to 68% for TCC and 20 to 75% for TCS. Increased solid retention times during sludge treatment operations were correlated with higher removals of TCC and TCS.

Rapid determination of natural and synthetic hormones in biosolids and poultry manure by isotope dilution GC-MS/MS.

The release of hormones into the environment due to land application of biosolids and manure is a cause of concern for their potential impacts. This paper presents the development of a rapid and sensitive method, based on extraction, for the analysis of 13 hormones in biosolids and poultry manure. A simultaneous derivatization of hydroxyl and ketone groups was carried out for the determination of hormones by GC–MS/MS. The method was validated in three matrices (sewage sludge, manure, and broiler litter). Recoveries from spiked samples at three concentration levels (50, 25, and 10 ng/g) ranged from 76 to 124% with relative SDs ≤ 16%. Method detection limits for the three matrices were in the range of 0.5–3.0 ng/g dry weight. The optimized method was applied to biosolid and poultry manure samples collected in Spain. Only seven of the 13 studied hormones were detected in the different samples. trans-Androsterone was detected at high levels (up to 3.1 μg/g in biosolid samples). Estrone and estradiol were the two hormones detected at higher levels in layer manure, whereas estrone and 4-androstene-3,17-dione presented the highest levels in broiler litter.