Notes on Urban Sludge
From straightjacket
Contents |
Notes
Promising looking sources
Centre for Health and the Global Environment (Harvard)
- Sewage Sludge: Potential Human Health Impacts, Tom Burke, Ph.D., M.P.H. (2004) (Real media)
- Lectures on Chemicals and Communities (2007) (List of all 2007 lectures)
- Many other interesting lectures (on video) can be found at http://chge.med.harvard.edu/programs/archive/index.html.
Articles from Pubmed
- Harrison, Ellen Z, Summer Rayne Oakes, Matthew Hysell, and Anthony Hay. Organic chemicals in sewage sludges. The Science of the total environment 367, no. 2-3 (August 31, 2006): 481-97.
- Sewage sludges are residues resulting from the treatment of wastewater released from various sources including homes, industries, medical facilities, street runoff and businesses. Sewage sludges contain nutrients and organic matter that can provide soil benefits and are widely used as soil amendments. They also, however, contain contaminants including metals, pathogens, and organic pollutants. Although current regulations require pathogen reduction and periodic monitoring for some metals prior to land application, there is no requirement to test sewage sludges for the presence of organic chemicals in the U. S. To help fill the gaps in knowledge regarding the presence and concentration of organic chemicals in sewage sludges, the peer-reviewed literature and official governmental reports were examined. Data were found for 516 organic compounds which were grouped into 15 classes. Concentrations were compared to EPA risk-based soil screening limits (SSLs) where available. For 6 of the 15 classes of chemicals identified, there were no SSLs. For the 79 reported chemicals which had SSLs, the maximum reported concentration of 86% exceeded at least one SSL. Eighty-three percent of the 516 chemicals were not on the EPA established list of priority pollutants and 80% were not on the EPA's list of target compounds. Thus analyses targeting these lists will detect only a small fraction of the organic chemicals in sludges. Analysis of the reported data shows that more data has been collected for certain chemical classes such as pesticides, PAHs and PCBs than for others that may pose greater risk such as nitrosamines. The concentration in soil resulting from land application of sludge will be a function of initial concentration in the sludge and soil, the rate of application, management practices and losses. Even for chemicals that degrade readily, if present in high concentrations and applied repeatedly, the soil concentrations may be significantly elevated. The results of this work reinforce the need for a survey of organic chemical contaminants in sewage sludges and for further assessment of the risks they pose.
- Xia, Kang, Alok Bhandari, Keshav Das, and Greg Pillar. Occurrence and fate of pharmaceuticals and personal care products (PPCPs) in biosolids. Journal of environmental quality 34, no. 1: 91-104.
- Each year, large quantities of pharmaceuticals and personal care products (PPCPs) are used worldwide. Once conveyed to wastewater treatment plants, PPCPs can remain unchanged or undergo partial or complete transformation during wastewater treatment processes before discharge into the environment via effluent and biosolids for land application. Biosolids can be a major sink for some PPCPs. Previous investigations have indicated that land application of biosolids may be a potential important route through which PPCPs enter the environment. However, no information is available on exactly how closely the concentrations of PPCPs in the environmental media are related to the land application of PPCP-containing biosolids. This paper reviews currently available information on the occurrence of PPCPs in biosolids, methods of analysis, the potential fate of PPCPs in biosolids-applied soils, and composting as a potential means for removal of PPCPs from biosolids.
Carola's Articles
- Falconer, Ian R. Chapman, Heather F. Moore, Michael R. and Ranmuthugala, Geetha. (2006) Endocrine-disrupting compounds: a review of their challenge to sustainable and safe water supply and water reuse. Environ Toxicol 21: 181–191
- Fent, Karl. Weston, Anna A. and Caminada, Daniel. (2006) Ecotoxicology of Human Pharmaceuticals. Aquatic Toxicology, 76, 122-159
- Keenan, H.E., et al., Environmental fate and partition co-efficient of oestrogenic compounds in sewage treatment process. Environm. Res. (2007),doi:10.1016/j.envres.2007.07.007
- Kim, Sungpyo and Aga, Diana S. (2007) Potential Ecological and Human Health Impacts of Antibiotics and Antibiotic-Resistant Bacteria from Wastewater Treatment Plants. Journal ofToxicology and Environmental Health, Part B, 10:8, 559 - 573
- Nikolaou, Anastasia. Meric, Sureyya and Fatta, Despo. (2007) Occurrence patterns of pharmaceuticals in water and wastewater environments. Anal Bioanal Chem 387:1225–1234
Wikipedia
Collected resources - not reviewed
Contents of sludge
- Jones-Lepp, T L, and Rick Stevens. Pharmaceuticals and personal care products in biosolids/sewage sludge: the interface between analytical chemistry and regulation. Analytical and bioanalytical chemistry 387, no. 4 (February 2007): 1173-83.
- Modern sanitary practices result in large volumes of human waste, as well as domestic and industrial sewage, being collected and treated at common collection points, wastewater treatment plants (WWTPs). In recognition of the growing use of sewage sludge as fertilizers and soil amendments, and the scarcity of current data regarding the chemical constituents in sewage sludge, the US National Research Council (NRC) in 2002 produced a report on sewage sludge. Among the NRC's recommendations was the need for investigating the occurrence of pharmaceuticals and personal care products (PPCPs) in sewage sludge. PPCPs are a diverse array of non-regulated contaminants that had not been studied in previous sewage sludge surveys but which are likely to be present. The focus of this paper will be to review the current analytical methodologies available for investigating whether pharmaceuticals are present in WWTP-produced sewage sludge, to summarize current regulatory practices regarding sewage sludge, and to report on the presence of pharmaceuticals in sewage sludge.
- Jones, Oliver A, John N Lester, and Nick Voulvoulis. Pharmaceuticals: a threat to drinking water?. Trends in biotechnology 23, no. 4 (April 2005): 163-7.
- Recently, considerable interest has developed regarding the presence of pharmaceuticals in the environment, but there has been comparatively little study on the potential of these substances to enter potable supplies. This is surprising because drinking water would provide a direct route into the body for any drugs that might be present. Although many countries employ advanced treatments, such as granular activated carbon, membrane technologies, ozonation and ultraviolet radiation, for treating water intended for human consumption, some compounds have been shown to be unaffected by such processes. Here, we examine the levels of drug substances reported in drinking water around the world. The possible implications of the presence of these compounds are highlighted and assessed, and recommendations are made for further research.
- Meenakshi, and R C Maheshwari. Fluoride in drinking water and its removal. Journal of hazardous materials 137, no. 1 (September 1, 2006): 456-63.
- Excessive fluoride concentrations have been reported in groundwaters of more than 20 developed and developing countries including India where 19 states are facing acute fluorosis problems. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. In this paper, a broad overview of the available technologies for fluoride removal and advantages and limitations of each one have been presented based on literature survey and the experiments conducted in the laboratory with several processes. It has been concluded that the selection of treatment process should be site specific as per local needs and prevailing conditions as each technology has some limitations and no one process can serve the purpose in diverse conditions.
Processing
- Babel, Sandhya, and Dominica del Mundo Dacera. Heavy metal removal from contaminated sludge for land application: a review. Waste management (New York, N.Y.) 26, no. 9 (2006): 988-1004.
- In recent years, various methods for heavy metal removal from sewage sludge have been extensively studied in order to minimize the prospective health risks of sludge during land application. In this paper, a comparative review and critical analysis of the application of chemical extraction, bioleaching, electroreclamation, and supercritical fluid extraction (SFE), in removing heavy metals from contaminated sludges is presented. Moreover, speciation studies, which can indicate ease of leachability of the different forms of heavy metals in sludge, are also presented. Experimental studies revealed a broad range in metal extraction efficiencies of the different extraction technologies. Acid treatment seemed to effectively remove Cd, attaining as much as 100% removal for some studies, as compared to bioleaching. SFE also gave higher removal efficiency than bioleaching. Cr, Pb and Ni seemed to be also effectively removed by the acid treatment. For the removal of Cu, Mn and Zn, the bioleaching process seemed to be appropriate with maximum removal efficiencies of 91%, 93% and 96% for the three metals, respectively, and as high as 64% minimum removal efficiency for Zn. The SFE process also gave good results for Cu, Mn and Zn removal. Electroreclamation exhibited better removal efficiency for Mn, but is still inferior to acid treatment and bioleaching processes. For chemical extraction, because of the adverse impacts that can result from the use of inorganic acids and complexing agents, interest can be directed more toward utilizing organic acids as extracting agents because of their biodegradability and capability to remove metals at mildly acidic condition, hence requiring less acid. The bioleaching process, although it seems to give a higher yield of metal extraction with lower chemical cost than chemical extraction, may be limited by the inability of the system to cope with the natural environmental conditions, requires strict monitoring of aeration rate and temperature and has applicability to only low sludge solids concentration. A full-scale study would be useful to better assess the efficiency of the process. The electroreclamation technology is limited by its relatively higher energy consumption and limited applicability to sludge. The SFE method, on the other hand, is limited by the complexity of the process and the cost of ligands suitable for effective metal extraction. Both of these technologies are still in their early stage of application and hence there is a need for further basic and applied studies. Finally, the common advantage for almost all treatment technologies studied is that the extraction efficiencies for some metals are high enough to remove metals from sludge to levels suitable for land application.
- Ekama, G A, S W Sötemann, and M C Wentzel. Biodegradability of activated sludge organics under anaerobic conditions. Water research 41, no. 1 (January 2007): 244-52.
- From an experimental and theoretical investigation of the continuity of activated sludge organic (COD) compounds along the link between the fully aerobic or N removal activated sludge and anaerobic digestion unit operations, it was found that the unbiodegradable particulate organics (i) originating from the influent wastewater and (ii) generated by the activated sludge endogenous process, as determined from response of the activated sludge system, are also unbiodegradable under anaerobic digestion conditions. This means that the activated sludge biodegradable organics that can be anaerobically digested can be calculated from the active fraction of the waste activated sludge based on the widely accepted ordinary heterotrophic organism (OHO) endogenous respiration/death regeneration rates and unbiodegradable fraction. This research shows that the mass balances based steady state and dynamic simulation activated sludge, aerobic digestion and anaerobic digestion models provide internally consistent and externally compatible elements that can be coupled to produce plant wide steady state and dynamic simulation WWTP models.
- Jimenez, B. Helminth ova removal from wastewater for agriculture and aquaculture reuse. Water science and technology : a journal of the International Association on Water Pollution Research 55, no. 1-2 (2007): 485-93.
- In the new version of the World Health Organization (WHO), water reuse guidelines helminth ova are considered one of the main target pollutants to be removed from wastewater reuse for agriculture and aquaculture purposes. In spite of this, along with the fact that helminth ova have been considered the main health risk to wastewater reuse for agriculture for at least 20 years, relatively little research has been done to control helminth ova in the wastewater treatment field. This paper addresses (1) characteristics of helminth ova and differences with microorganisms; (2) the most frequent helminth ova genus found in wastewater; (3) helminth ova content in developed and developing countries wastewater; (4) reasons why conventional disinfection methods cannot be applied; (5) main removal mechanisms; and (6) processes that in practice have effectively removed or inactivated helminth ova.
- Muñoz, Raul, and Benoit Guieysse. Algal-bacterial processes for the treatment of hazardous contaminants: a review. Water research 40, no. 15 (August 2006): 2799-815.
- Microalgae enhance the removal of nutrients, organic contaminants, heavy metals, and pathogens from domestic wastewater and furnish an interesting raw material for the production of high-value chemicals (algae metabolites) or biogas. Photosynthetic oxygen production also reduces the need for external aeration, which is especially advantageous for the treatment of hazardous pollutants that must be biodegraded aerobically but might volatilize during mechanical aeration. Recent studies have therefore shown that when proper methods for algal selection and cultivation are used, it is possible to use microalgae to produce the O(2) required by acclimatized bacteria to biodegrade hazardous pollutants such as polycyclic aromatic hydrocarbons, phenolics, and organic solvents. Well-mixed photobioreactors with algal biomass recirculation are recommended to protect the microalgae from effluent toxicity and optimize light utilization efficiency. The optimum biomass concentration to maintain in the system depends mainly on the light intensity and the reactor configuration: At low light intensity, the biomass concentration should be optimized to avoid mutual shading and dark respiration whereas at high light intensity, a high biomass concentration can be useful to protect microalgae from light inhibition and optimize the light/dark cycle frequency. Photobioreactors can be designed as open (stabilization ponds or high rate algal ponds) or enclosed (tubular, flat plate) systems. The latter are generally costly to construct and operate but more efficient than open systems. The best configuration to select will depend on factors such as process safety, land cost, and biomass use. Biomass harvest remains a limitation but recent progresses have been made in the selection of flocculating strains, the application of bioflocculants, or the use of immobilized biomass systems.
- White, John R, Marco A Belmont, and Chris D Metcalfe. Pharmaceutical compounds in wastewater: wetland treatment as a potential solution. TheScientificWorldJournal 6 (2006): 1731-6.
- Pharmaceutical compounds are being released into the aquatic environment through wastewater discharge around the globe. While there is limited removal of these compounds within wastewater treatment plants, wetland treatment might prove to be an effective means to reduce the discharge of the compounds into the environment. Wetlands can promote removal of these pharmaceutical compounds through a number of mechanisms including photolysis, plant uptake, microbial degradation, and sorption to the soil. We review relevant laboratory research on these various mechanisms and provide data on the few studies that have examined wetland removal. There is a need to document the degree to which various pharmaceutical compounds are removed in full-scale treatment wetlands, as there is a paucity of data on overall pharmaceutical removal rates.
Monitoring
- Buchberger, Wolfgang W. Novel analytical procedures for screening of drug residues in water, waste water, sediment and sludge. Analytica chimica acta 593, no. 2 (June 19, 2007): 129-39.
- Traces of pharmaceuticals are continuously introduced into the aquatic environment mainly by sewage treatment plant effluents. Final data about their impact on the ecosystem are still partly missing. Progress in instrumental analytical chemistry has resulted in the availability of methods that allow a monitoring of these pollutants at ng L(-1) levels. In this review the state-of-the-art of residue analysis of pharmaceuticals by chromatographic and electrophoretic techniques is summarized. Improvements in detection limits over the past years have mainly been due to sophisticated mass spectrometric detection techniques. Furthermore, robust sample preparation and preconcentration protocols based on solid-phase extraction and related procedures have contributed significantly to the achievements observed so far. This review also covers several immunochemical approaches which may serve as an inexpensive alternative for quick screening of samples.
Policy
- ***** Schoof, Rosalind A, and Dana Houkal. The evolving science of chemical risk assessment for land-applied biosolids. Journal of environmental quality 34, no. 1: 114-21.
- Biosolids, effluents, and manures are widely applied to agricultural land and other land with varying degrees of pretreatment or control. Regulations governing land application of biosolids take several broad forms in different countries, including limitations based on rates that do not lead to increases in background chemical concentrations or risk assessment approaches such as those used in the United States. Risk assessment is a process that is inherently limited by currently available information and practices, and consequently, risk-based land application limits must be reevaluated periodically. For complex mixtures such as biosolids, three principal categories of information will be affected by changing practices and scientific advances: (i) chemical constituents present in the material, (ii) the nature of expected exposures, and (iii) toxicity of the chemical constituents. New analytical methods and lower detection limits will affect chemical identification in wastes. Approaches to exposure assessment, such as increasing emphasis on probabilistic analyses, will continue to evolve, and exposure assumptions will change as new studies provide better data on factors such as soil ingestion, plant uptake of chemicals, and bioavailability of chemicals in soil. Similarly, toxicity assessments will be updated as new studies are conducted. The evolving science over the past decade is illustrated by comparing approaches used by the USEPA to assess human health and ecological risks for the Part 503 rule compared with the more recent evaluation of dioxins and related compounds in biosolids. While risks of chemicals in land-applied biosolids and other residuals need to be periodically re-evaluated, such re-evaluations may take forms other than full risk assessments.
- Rose, J B. Water reclamation, reuse and public health. Water science and technology : a journal of the International Association on Water Pollution Research 55, no. 1-2 (2007): 275-82.
- The number of people who have limited access to high-quality water has increased, and while this is a growing global crisis, water issues, problems and solutions are often seen as localised. Water reuse and reclamation will play a significant role in achieving sustainability and public health protection in the future. The wastewater and reuse community should be responsible for monitoring sewage impacts and improvements as demonstrated through pathogen reduction with appropriate treatment. Viruses, Cryptosporidium and Giardia can all be reduced during treatment anywhere from 99% to 99.9999%, achieving drinking water quality, if so desired. Recommendations to achieve better access to scientific information for decision making include: 1) developing a global data base for biological contaminant loading from wastewater and 2) defining the public health protection via reuse and reclamation.
