In response to the U.S. National Academies' call for a better assessment of chemical pollutants contained in the approximately 6.9 million dry tons of digested municipal sludge produced annually in the United States, the mean concentration of 72 pharmaceuticals and personal care products (PPCP) were determined in 110 biosolids samples collected by the U.S. Environmental Protection Agency (EPA) in its 2001 National Sewage Sludge Survey. Composite samples of archived biosolids, collected at 94 U.S. wastewater treatment plants from 32 states and the District of Columbia, were analyzed by liquid chromatography tandem mass spectrometry using EPA Method 1694. Thirtyeight (54%) of the 72 analytes were detected in at least one composite sample at concentrations ranging from 0.002 to 48 mg kg −1 dry weight. Triclocarban and triclosan were the most abundant analytes with mean concentrations of 36 ± 8 and 12.6 ± 3.8 mg kg −1 (n = 5), respectively, accounting for 65% of the total PPCP mass found. The loading to U.S. soils from nationwide biosolids recycling was estimated at 210-250 metric tons per year for the sum of the 72 PPCPs investigated. The results of this nationwide reconnaissance of PPCPs in archived U.S. biosolids mirror in contaminant occurrences, frequencies and concentrations, those reported by the U.S. EPA for samples collected in 2006/07. This demonstrates that PPCP releases in U.S. biosolids have been ongoing for many years and the most abundant PPCPs appear to show limited fluctuations in mass over time when assessed on a nationwide basis. The here demonstrated use of five mega composite samples holds promise for conducting cost-effective, routine monitoring on a regional basis.

Municipal biosolids are in widespread use as additives to agricultural soils in the United States. Although it is well known that digested sewage sludge is laden with organic wastewater contaminants, the fate and behavior of micropollutants in biosolids-amended agricultural soils remain unclear. An outdoor mesocosm study was conducted in Baltimore, Maryland, to explore the fate of 72 pharmaceuticals and personal care products (PPCPs) over the course of three years in biosolids/soil mixtures (1:2) that were placed in plastic containers made from polyvinylchloride and kept exposed to ambient outdoor conditions. Of the 72 PPCPs tested for using EPA Method 1694, 15 were initially detected in the soil/biosolids mixtures at concentrations ranging from low parts-per-billion to parts-per-million levels. The antimicrobials triclocarban and triclosan showed the highest initial concentrations at 2715 and 1265 μg kg Consistent with other outdoor degradation studies, chemical half-lives determined empirically exceeded those reported from laboratory studies or predicted from fate models. Study results suggest that PPCPs shown in the laboratory to be readily biotransformable can persist in soils for extended periods of time when applied in biosolids. This study provides the first experimental data on the persistence in biosolids-amended soils for ciprofloxacin, diphenhydramine, doxycycline, 4-epitetracycline, gemfibrozil, miconazole, norfloxacin, ofloxacin, and thiabendazole.

Summary 1.The assessment of the environmental hazards posed by chemical pollutants typically results from single-species tests that are extrapolated to ecosystems. The aim of the present study was to compare this type of extrapolation for a herbicide with the chronic effects that may be observed at a community level and to evaluate currently applied risk assessment strategies for their ability to predict chemical effects on complex communities. 2. Freshwater periphyton communities, grown in indoor aquaria, were exposed to the pollutant diuron for 3 months. Acute toxic effects of diuron were detected as photosynthesis inhibition using quenching analysis of chla-fluorescence. Chronic effects of the herbicide were observed in terms of changes in biomass and algal class composition as well as pollution-induced community tolerance (PICT). The PICT concept is based on a chemical exerting selection pressure on a community and therefore eliminating sensitive species. As a result, the measured community tolerance increases. 3. Short-term effects of diuron arise from 4-9 μ g L -1 as half-maximal effect concentration (EC 50 ). It is further shown that diuron concentrations down to 0·08 μ g L -1 caused chronic effects in two independent microcosm studies. The observed threshold concentration of 0·08 μ g L -1 still caused changes in biomass and class composition as well as an increased community tolerance. The determined EC 50 values increased by a factor of 2-3 in diuron-exposed periphyton communities. This threshold value could not be predicted by advanced extrapolation methods such as species sensitivity distribution or acute-to-chronic effect ratios. 4. Synthesis and applications . The chronic community-level effects of the pollutant diuron were not predictable from single-species tests. However, regulations such as the EC Water Framework Directive or the EC-REACH process (Registrations, Evaluation and Authorisation of Chemicals) rely on this type of information. The management of chemicals in the environment should be based upon higher-tier assessment tools. Species interaction, detectable and quantifiable by the PICT methodology, may serve as a prognostic tool in chemical hazard assessment when extrapolating effects from single-species tests to community level.

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