Professor David Graham

Professor of Ecosystems Engineering

Email: david.graham@ncl.ac.uk
Telephone: +44 (0) 191 208 7930
Fax: +44 (0) 191 208 6502
Address: School of Engineering
Room 3.04
Cassie Building
Newcastle University
Newcastle upon Tyne
NE1 7RU
UK

Background

Introduction

Engineering microbiology often relies on pseudo-theory in the development of descriptive and design tools; however, such methods rarely describe real systems with consistency. Our work combines methods from engineering, theoretical ecology, mathematics, biochemistry, and molecular biology to solve problems in environmental engineering at a fundamental level. Research topics include biological waste treatment, ecotoxicology, bioremediation, and the environmental fate and impacts of trace and genetic contaminants. Current research projects includes 1) the transmission, fate and impact of antibiotic resistance genes in the environment resulting from human activity; 2) energy minimization in water, wastewater and solid waste management systems; 3) the microbiology and ecology of greenhouse gas suppression and production in geochemical settings, especially in Polar regions; and 4) water and environmental quality in the developing and emerging world.

Qualifications

1992 PhD - University of Arizona, Tucson, AZ, USA
1981 MASc - University of British Columbia, Vancouver, BC, Canada
1977 BASc - University of British Columbia, Vancouver, BC, Canada

Previous Positions

2006-2009 Professor, University of Kansas, USA
2001 Visiting Fellow, University of Newcastle upon Tyne, UK
1999-2006 Associate Professor, University of Kansas, USA
1992-1999 Assistant Professor, University of Kansas, USA
1987-1992 Research Assistant/Associate, University of Arizona, USA
1985-1987 Instructor, Coordinator of Water Resources Option Civil Engineering Technology, BCIT, Burnaby, Canada
1979-1987 Design Engineer/Project Engineer/Contract Consultant, Sigma Resource Consultants, Vancouver, Canada

Other Positions

Adjunct Professor - University of Kansas (Department of Geology)
Visiting Professor (pending) - Indian Institute of Technology, Delhi (Department of Bioengineering and Biotechnology)

Publication and Research Summary

Recent Impact

Influencing international policy on antibiotic resistance

Examples of meeting Sustainable Development Goals

Research

Research Interests

Antimicrobial resistance: Drivers, environmental exposures and mitigation
Links between environmental quality and public health in the developing world
Low-energy water and wastewater treatment technolgies
Microbial genetics and environmental biotechnology
Polar microbiology and genetics

Current Work

Ecology and genetics of antibiotic genes and bacteria in wastewater treatment processes
Antibiotic resistance and infectious disease fate in surface waters in rural SE Asia
Modelling antibiotic resistance migration and fate in developing countries
Bioenergy production from rice straw and other refractory wastes
Microbial and functional biogeography of High Arctic ecosystems

Postgraduate Supervision - Primary Supervisor

Current PhD Students

Marcos Quintela Baluja (2014 – expected 2018) Urban Water Cycle and Antibiotic Resistance Genes Dissemination.
Cara Wray (2014 – expected 2018) Microbial Communities in Water Treatment Plants: Fate of Coliforms and other Bacteria.
Florence Jong (2015 – expected 2019) Low-energy Biological Treatment Technologies for Reducing Antibiotic Resistance Genes and Bacteria in Domestic Wastewater.
Joshua Bunce (2016 – expected 2019) Small-scale, Low Energy Waste Treatment Systems for N and P Removal in Decentralised Rural Applications.
Panagiota (Pani) Adamou (2016 – expected 2019) Assessing Tertiary Treatment Technologies for Reducing Antibiotic Resistance.
Amelie Ott (2017 – expected 2021) Modelling Antimicrobial Resistance Spread in Aquatic Systems in Emerging Countries.

Examples of Previous Graduates

Andrew Zealand (2013 – 2018) Operational Performance and Microbial Dynamics of Rice Straw Anaerobic Digestion.
Edmond Ndam (2011 – 2017) Treatment Technologies for Recycle Liquors: Nutrient Removal, Mass Balances, and Potential Recovery at Wastewater Treatment Plants.
Catherine Hands (2013 – 2016) Relationships between Zinc and Meropenem Resistance in the Natural Environment and Experimental Bioreactors.
Olorunwa Tijani (2010 – 2015) Anaerobic Digestion of Food Waste: A Case for Inclusion in Solid Waste Management Solutions for Nigeria.
Charles Knapp (1999 – 2002) Application of Molecular Techniques in Assessing Alachlor Transformation in Aquatic Mesocosms.
Hyung J Kim (1993 – 2003) Isolation, Structural Determination, and Characterization of a Novel Copper-binding Compound from Methylosinus trichosporium OB3b.

Impact on Antibiotic Resistance in the Environment

Examples of Recent Funding

Innovate UK/Newton Fund (2018-2020; £79.8K) Improving community health in Malaysia using sustainable decentralised wastewater treatment; PI, with two CIs
JPI-AMR (MRC) (2017-2020; £1.8M) DARWIN: Dynamics of antimicrobial resistance in the urban water cycle in Europe; CI (PI – DTU) with four CIs
EPSRC (2018-2020; £251.8K) Tackling AMR in Wastewater Systems with Sneaky Bacteria; PI
EPSRC IAA (2017-2018; £49.6K) Expanding the Reach of Multi-Disciplinary Environment and Health Research in SE Asia; PI, with one CI
NERC (AMR in the Real World) (2016-2018; £199K) Quantifying spatial AMR patterns across urban and rural landscapes; CI (PI - UoS), with one CI
EU-FP7 – Marie Curie Initial Training Networks (2013-2017; £4.2M) Microbial resource management and engineering in the urban water cycle, B Smets (PI) at DTU, with Graham and other CIs at Lisbon, Ghent & EAWAG

Teaching

Postgraduate Teaching

CEG8102: Introduction to Practical Hydraulics (Module Leader)
CEG8105: Solid Waste Management (Contributor)
CEG8198: MSc Project and Dissertation in Environmental Engineering (Project/Dissertation Supervisor)

Publications

Bunce JT, Ndam E, Ofiteru ID, Moore A, Graham DW. A Review of Phosphorus Removal Technologies and Their Applicability to Small-Scale Domestic Wastewater Treatment Systems. Frontiers in Environmental Science 2018, 6(8).
Lamba M, Gupta S, Shukla R, Graham DW, Sreekrishnan TR, Ahammad SZ. Carbapenem resistance exposures via wastewaters across New Delhi. Environment International 2018, 119, 302-308.
Jong M-C, Su J-Q, Bunce JT, Harwood CR, Snape JR, Zhu Y-G, Graham DW. Co-optimization of sponge-core bioreactors for removing total nitrogen and antibiotic resistance genes from domestic wastewater. Science of the Total Environment 2018, 634, 1417-1423.
Rodriguez DC, Ahammad ZS, Penuela GA, Graham DW. Effect of β -lactamases associated to the resistance of β -lactam antibiotics on the treatment of wastewater. Journal of Environmental Chemical Engineering 2018, Epub ahead of print.
Zealand AM, Mei R, Papachristodoulou P, Roskilly AP, Liu WT, Graham DW. Microbial Community Composition and Diversity in Rice Straw Digestion Bioreactors with and without Dairy Manure. Applied Microbiology and Biotechnology 2018, ePub ahead of Print.
Velasquez-Orta SB, Heidrich O, Black K, Graham D. Retrofitting options for wastewater networks to achieve climate change reduction targets. Applied Energy 2018, 218, 430-441.
Hong P-Y, Julian TR, Pype M-L, Jiang SC, Nelson KL, Graham DW, Pruden A, Manaia CM. Reusing Treated Wastewater: Consideration of the Safety Aspects Associated with Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes. Water 2018, 10(3), 244.
Keen PL, Knapp CW, Hall KJ, Graham DW. Seasonal dynamics of tetracycline resistance gene transport in the Sumas River agricultural watershed of British Columbia, Canada. Science of the Total Environment 2018, 628-629, 490-498.
Wu D, Huang X, Sun J, Graham DW, Xie B. Antibiotic resistance genes and associated microbial community conditions in aging landfill systems. Environmental Science & Technology 2017, 51(21), 12859-12867.
Zealand AM, Roskilly AP, Graham DW. Effect of feeding frequency and organic loading rate on biomethane production in the anaerobic digestion of rice straw. Applied Energy 2017, 207, 156-165.
Bundy CA, Wu D, Jong M-C, Edwards SR, Ahammad ZS, Graham DW. Enhanced denitrification in Downflow Hanging Sponge reactors for decentralised domestic wastewater treatment. Bioresource Technology 2017, 226, 1-8.
Lamba M, Graham DW, Ahammad SZ. Hospital wastewater releases of carbapenem-resistance pathogens and genes in urban India. Environmental Science & Technology 2017, 51(23), 13906–13912.
Zealand AM, Roskilly AP, Graham DW. The Effect of Feeding Frequency and Organic Loading Rate on the Anaerobic Digestion of Chinese Rice Straw. In: 8th International Conference on Applied Energy (ICAE2016). 2017, Beijing, China: Elsevier Ltd.
deNoyelles J, Smith VH, Kastens JH, Bennett L, Lomas JM, Knapp CW, Bergin SP, Dewey SL, Chapin BRK, Graham DW. A 21-year record of vertically migrating subepilemnetic populations of Chyptomonas spp. Inland Waters 2016, 6(2), 173-184.
Kinnunen M, Dechesne A, Proctor CR, Hammes F, Johnson D, Quintela-Baluja MQ, Graham DW, Daffonchio D, Fodelianakis S, Hahn N, Boon N, Smets BF. A conceptual framework for invasion in microbial communities. The ISME Journal 2016, 10, 2773-2779.
Graham DW, Knapp CW, Christensen BT, McCluskey S, Dolfing J. Appearance of β-lactam resistance genes in agricultural soils and clinical isolates over the 20th century. Scientific Reports 2016, (6), 21550.
Valdivia-Garcia M, Weir P, Frogbrook Z, Graham DW, Werner D. Climatic, geographic and operational determinants of trihalomethanes (THMs) in drinking water systems. Scientific Reports 2016, 6, 35027.
McCann CM, Wade MJ, Gray ND, Roberts JA, Hubert CRJ, Graham DW. Microbial Communities in a High Arctic polar desert landscape. Frontiers in Microbiology 2016, 7, 419.
Graham DW. Antibiotic Resistance in the Environment: Not the Usual Suspects. Chemistry and Biology 2015, 22(7), 805-806.
Mao Y, Graham DW, Tamaki H, Zhang T. Dominant and novel clades of Candidatus Accumulibacter phosphatis in 18 globally distributed full-scale wastewater treatment plants. Scientific Reports 2015, 5, 11857.
Christgen B, Yang Y, Ahammad SZ, Li B, Rodriquez DC, Zhang T, Graham DW. Metagenomics shows low-energy anaerobic-aerobic treatment reactors reduce antibiotic resistance gene dissemination from domestic wastewater. Environmental Science & Technology 2015, 49(4), 2577-2584.
Wu D, Huang Z, Yang K, Graham DW, Xie B. Relationships between Antibiotics and Antibiotic Resistance Gene Levels in Municipal Solid Waste Leachates in Shanghai, China. Environmental Science & Technology 2015, 49(7), 4122-4128.
Quintela-Baluja M, Chan WC, Alnakip ME, Abouelnaga M, Graham DW. Sanitation, Water Quality, and Antibiotic Resistance Dissemination. In: Méndez-Vilas, A, ed. The Battle Against Microbial Pathogens: Basic Science, Technological Advances and Educational Programs. Fomatex Research Center, 2015, pp.965-975.
Calleja C, Graham DW. Water Managers have a Vital Role to Play in Stemming Antibiotic Resistance. The Environment 2015, 5, 24-28.
Ahammad ZS, Sreekrishnan TR, Hands CL, Knapp CW, Graham DW. Increased Waterborne bla_NDM-1 Resistance Gene Abundances Associated with Seasonal Human Pilgrimages to the Upper Ganges River. Environmental Science & Technology 2014, 48(5), 3014-3020.
Gray ND, McCann CM, Christgen B, Ahammad SZ, Roberts JA, Graham DW. Soil geochemistry confines microbial abundances across an Arctic landscape; Implications for net carbon exchange with the atmosphere. Biogeochemistry 2014, 120(1-3), 307-317.
Ahammad SZ, Yakubu A, Rodriguez DC, Dolfing J, Graham DW. Source separation increases methane yields for waste-to-energy applications in the personal care product industry. Chemical Engineering Journal 2014, 244, 195-201.
Graham DW, Collignon P, Davies J, Larsson DGJ, Snape J. Underappreciated Role of Regionally Poor Water Quality on Globally Increasing Antibiotic Resistance. Environmental Science & Technology 2014, 48(20), 11746–11747.
Ahammad SZ, Bereslawski JL, Dolfing J, Mota C, Graham DW. Anaerobic-aerobic sequencing bioreactors improve energy efficiency for treatment of personal care product industry wastes. Bioresource Technology 2013, 139, 73-79.
Ahammad SZ, Zealand A, Dolfing J, Mota C, Armstrong DV, Graham DW. Low-energy treatment of colourant wastes using sponge biofilters for the personal care product industry. Bioresource Technology 2013, 129, 634-638.
Bellucci M, Ofiteru ID, Head IM, Curtis TP, Graham DW. Nitrification in hybrid bioreactors treating simulated domestic wastewater. Journal of Applied Microbiology 2013, 115(2), 621-630.
Finley RL, Collignon P, Larsson DGJ, McEwen SA, Li X-Z, Gaze WH, Reid-Smith R, Timinouni M, Graham DW, Topp E. The scourge of antibiotic resistance: the important role of the environment. Clinical Infectious Diseases 2013, 57(5), 704-710.
Ahammad SZ, Graham DW, Dolfing J. Wastewater Treatment: Biological. In: Jorgensen, SE, ed. Encyclopedia of Environmental Management. Bosa Roca: Taylor & Francis, 2013, pp.2645-2655.
Ofiteru ID, Ferdes M, Knapp CW, Graham DW, Lavric V. Conditional confined oscillatory dynamics of Escherichia coli strain K12-MG1655 in chemostat systems. Applied Microbiology and Biotechnology 2012, 94(1), 185-192.
Ahammad SZ, Yakubu A, Dolfing J, Mota C, Graham DW. Feasibility tests for treating shampoo and hair colorant wastewaters using anaerobic processes. Water Science and Technology 2012, 65(2), 303-308.
Olivares-Rieumont S, Lima L, Rivero S, Graham DW, Alonso-Hernandez C, Bolano Y. Mercury Levels in Sediments and Mangrove Oysters, Crassostrea rizophorae, from the North Coast of Villa Clara, Cuba. Bulletin of Environmental Contamination and Toxicology 2012, 88(4), 589-593.
Knapp CW, Lima L, Olivares-Rieumont S, Bowen E, Werner D, Graham DW. Seasonal variations in antibiotic resistance gene transport in the Almendares River, Havana, Cuba. Frontiers in Microbiology 2012, 3, 396.
El Ghazouani A, Baslé A, Gray J, Graham DW, Firbank SJ, Dennison C. Variations in methanobactin structure influences copper utilization by methane-oxidizing bacteria. Proceedings of the National Academy of Sciences 2012, 109(22), 8400-8404.
Graham DW, Olivares-Rieumont S, Knapp CW, Lima L, Werner D, Bowen E. Antibiotic resistance gene abundances associated with waste discharges to the Almendares River near Havana, Cuba. Environmental Science & Technology 2011, 45(2), 418-424.
Knapp CW, McCluskey SM, Singh BK, Campbell CD, Hudson G, Graham DW. Antibiotic resistance gene abundances correlate with metal and geochemical conditions in archived Scottish soils. PLoS One 2011, 6(11), e27300.
Giesen MJ, Mazel AD, Graham DW, Warke PA. Care and Management of Ancient Stone Monuments during Environmental Change. International Journal of Heritage and Sustainable Development 2011, 1(1), 60-71.
El Ghazouani A, Basle A, Firbank SJ, Knapp CW, Gray J, Graham DW, Dennison C. Copper-Binding Properties and Structures of Methanobactins from Methylosinus trichosporium OB3b. Inorganic Chemistry 2011, 50(4), 1378-1391.
Chi Fru E, Gray ND, McCann C, Baptista JDC, Christgen B, Talbot HM, El Ghazouani A, Dennison C, Graham DW. Effects of copper mineralogy and methanobactin on cell growth and sMMO activity in Methylosinus trichosporium OB3b. Biogeosciences 2011, 8, 2887-2894.
Bellucci M, Ofiteru ID, Graham DW, Head IM, Curtis TP. Low Dissolved Oxygen Nitrifying Systems Exploit Ammonia-Oxidizing Bacteria With Unusually High Yield. Applied and Environmental Microbiology 2011, 77(21), 7787-7796.
Chi-Fru E, Ofiteru ID, Lavric V, Graham DW. Non-linear population dynamics in chemostats associated with live-dead cell cycling in Escherichia coli strain K12-MG1655. Applied Microbiology and Biotechnology 2011, 89(3), 791-998.
Graham DW, Kim HJ. Production, isolation, purification and functional characterisation of methanobactins. In: Rosenzweig, A., Ragsdale, S.W, ed. Methods in Methane Metabolism, Part B: Methanotrophy. Amsterdam; Boston: Academic Press, 2011, pp.227-245.
Kulczycki E, Fowle DA, Kenward PA, Leslie K, Graham DW, Roberts JA. Stimulation of methanotroph activity by Cu-substituted borosilicate glass. Geomicrobiology Journal 2011, 28(1), 1-10.
Lavric V, Graham DW. Birth, growth and death as structuring operators in bacterial population dynamics. Journal of Theoretical Biology 2010, 264(1), 45-54.
Graham DW, Trippett C, Dodds WK, O'Brien JM, Banner EBK, Head IM, Smith MS, Yang RK, Knapp CW. Correlations between in situ denitrification activity and nir-gene abundances in pristine and impacted prairie streams. Environmental Pollution 2010, 158(10), 3225-3229.
Knapp CW, Zhang W, Sturm BSM, Graham DW. Differential fate of erythromycin and beta-lactam resistance genes from swine lagoon waste under different aquatic conditions. Environmental Pollution 2010, 158(5), 1506-1512.
Knapp CW, Dolfing J, Ehlert PAI, Graham DW. Evidence of increasing antibiotic resistance gene abundances in archived soils since 1940 . Environmental Science & Technology 2010, 44(2), 580-587.
Peltier E, Vincent J, Finn C, Graham DW. Zinc-induced antibiotic resistance in activated sludge bioreactors. Water Research 2010, 44(13), 3829-3836.
Zhang W, Sturm BSM, Knapp CW, Graham DW. Accumulation of Tetracycline Resistance Genes in Aquatic Biofilms Due to Periodic Waste Loadings from Swine Lagoons. Environmental Science and Technology 2009, 43(20), 7643-7650.
De La Rosa D, Lima L, Olivares-Rieumont S, Graham DW, Enriquez I, Diaz O, Bastías JM, Muñoz O. Assessment of Total Mercury Levels in Clarias gariepinus from the Sagua la Grande River, Cuba. Bulletin of Environmental Contamination and Toxicology 2009, 82(1), 101-105.
Knapp CW, Dodds WK, Wilson KC, O'Brien JM, Graham DW. Spatial Heterogeneity of Denitrification Genes in a Highly Homogenous Urban Stream. Environmental Science and Technology 2009, 43(12), 4273-4279.
Engemann C, Keen P, Knapp CW, Hall K, Graham DW. Fate of tetracycline resistance genes in aquatic systems: Migration from the water column to peripheral biofilms. Environmental Science and Technology 2008, 42(14), 5131-5136.
Knapp CW, Engemann C, Hanson M, Keen P, Hall K, Graham DW. Indirect evidence of transposon-mediated selection of antibiotic resistance genes in aquatic systems at low-level oxytetracycline exposures. Environmental Science and Technology 2008, 42(14), 5348-5353.
Peak N, Knapp CW, Yang RK, Hanfelt MM, Smith MS, Aga DS, Graham DW. Abundance of six tetracycline resistance genes in wastewater lagoons at cattle feedlots with different antibiotic use strategies. Environmental Microbiology 2007, 9(1), 143-151.
Graham DW, Knapp CW, Van Vleck E, Bloor K, Lane T, Graham C. Experimental demonstration of chaotic instability in biological nitrification. ISME Journal 2007, 1(5), 385-393.
Knapp C, Fowle D, Kulczycki E, Roberts J, Graham D. Methane monooxygenase gene expression mediated by methanobactin in the presence of mineral copper sources. Proceedings of the National Academy of Sciences of the United States of America 2007, 104(29), 12040-12045.
Kulczycki E, Fowle DA, Knapp CW, Graham DW, Roberts JA. Methanobactin-promoted Dissolution of Cu-substituted Borosilicate Glass. Geobiology 2007, 5(3), 251-263.
Knapp CW, Graham DW. Nitrite-oxidizing bacteria guild ecology associated with nitrification failure in a continuous-flow reactor. FEMS Microbiology Ecology 2007, 62(2), 195-201.
Olivares Rieumont S, Lima L, de la Rosa D, Graham DW, Columbie I, Santana JL, Sánchez MJ. Water Hyacinths (Eichhornia crassipes) as Indicators of Heavy Metal Impact of a Large Landfill on the Almendares River near Havana, Cuba. Bulletin of Environmental Contamination and Toxicology 2007, 79(6), 583-587.
Engemann CA, Adams LM, Knapp CW, Graham DW. Disappearance of oxytetracycline resistance genes in aquatic systmes. FEMS Microbiology Letters 2006, 263(2), 176-182.
Gordon DA, Toth GP, Graham DW, Lazorchak JM, Reddy TV, Knapp CW, de Noyelles F, Campbell S, Lattier DL. Effects of secondary nutrient conditions on vitellogenin gene expression in male fathead minnows (Pimephales promelas) exposed to 17-[alpha]-ethynylestradiol in field mesocosms. Environmental Pollution 2006, 142(3), 559-566.
Olivares Rieumont S, de la Rosa D, Lima L, Graham DW, Alessandro KD´, Borroto J, Martínez FG, Sánchez J. Assessment of heavy metal levels in Almendares River sediments - Havana City, Cuba. Water Research 2005, 39(16), 3945-3953.
Knapp CW, Cardoza LA, Hawes J, Wellington EMH, Larive CK, Graham DW. Fate and Effects of Enrofloxacin in Aquatic Systems under Different Light Conditions. Environmental Science & Technology 2005, 39, 9140-9146.
Kim HJ, Galeva N, Larive CK, Alterman M, Graham DW. Purification and Physical—Chemical Properties of Methanobactin: A Chalkophore from Methylosinus trichosporium OB3b. Biochemistry 2005, 44(13), 5140-5148.
Knapp CW, Caquet T, Hanson ML, Lagadic L, Graham DW. Response of microbial communities to sudden exposure to deltamethrin in aquatic mesocosms. FEMS Microbiology Ecology 2005, 54(1), 157-165.
Chang LW, Toth GP, Gordon DA, Graham DW, Meier JR, Knapp CW, deNoyelles F, Campbell S, Lattier DL. Responses of molecular indicators of exposure in mesocosms: common carp (Cyprinus carpio) exponsed to the herbicides alachlor and atrazine. Environmental Toxicology & Chemistry 2005, 24(1), 190-197.
Graham DW, Smith VH. Designed ecosystem services: application of ecological principles in wastewater treatment engineering. Frontiers in Ecology and the Environment 2004, 2(4), 199-206.
Kim HJ, Graham DW, DiSpirito AA, Alterman MA, Galeva N, Larive CK, Asunskis D, Sherwood PMA. Methanobactin, a Copper-Acquisition Compound from Methane-Oxidizing Bacteria. Science 2004, 305(5690), 1612-1615.
Smith MS, Yang RK, Knapp CW, Niu Y, Peak N, Hanfelt M, Galland JS, Graham DW. Quantification of Tetracycline Resistance Genes in Feedlot Lagoons Using Real-time PCR. Applied and Environmental Microbiology 2004, 70, 7372-7377.
Knapp CW, Graham DW, Steedman RJ, de Noyelles F. Deep chlorophyll maxima in small forest lakes after experimental catchment and shoreline logging. Boreal Environment Research 2003, 8(1), 9-18.
Ensz A, Knapp CW, Graham DW. Influence of Autochthonous Dissolved Organic Carbon and Nutrient Limitation on Alachlor Biotransformation in Aerobic Aquatic Systems. Environmental Science & Technology 2003, 37(18), 4157-4162.
Knapp CW, Graham DW, Berardesco G, de Noyelles F, Cutak BJ, Larive CK. Nutrient level, microbial community conditions, and alachlor transformation in aerobic aquatic mesocosms. Water Research 2003, 37(19), 4761-4769.
Curtis TP, Head IM, Graham DW. Theoretical Ecology for engineering biology. Environmental Science & Technology 2003, 37(3), 64A-70A.