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*Student Mentee, #Equal contributions


  • *James, B.D., Ward, C.P., Hahn, M.H, Thorpe, S., Reddy, C.M. Minimizing the environmental impacts of plastic pollution through eco-design of products with low environmental persistence. In Press at ACS Sustainable Chemistry & Engineering.
  • *#Sun, Y., *Mazzotta, M.G., Miller, C.A., Apprill, A., Izallalen, M., Mazumder, S., Perri, S.T., Edwards, B., Reddy, C.M., #Ward, C.P. Distinct Microbial Communities Degrade Cellulose Diacetate Bioplastics in the Coastal Ocean. In Press at Applied & Environmental Microbiology.
  • *Freeman, D.H, Niles, S.F., Rodgers, R.P., French-McCay, D.P., Longnecker, K., Reddy, C.M., & Ward, C.P.  Hot and Cold: Photochemical Weathering Mediates Oil Properties and Fate Differently Depending on Seawater Temperature. 2023. Environmental Science & Technology. 57, 32, 11988-11998.
  • *Chen, S., Ward, C.P., & Long, M.H. Quantifying Pelagic Primary Production and Respiration via an Automated In-Situ Incubation System. In Press at Limnology and Oceanography: Methods.
  • *James, B., Karchner, S., *Walsh, A., Aluru, N., Franks, D., Sullivan, K., Reddy, C., Ward, C.P., Hahn, M. Formulation controls the potential toxicity of leachates from photoweathered polyethylene bags in developing zebrafish. 2023. Environmental Science & Technology. 57, 21, 7966–7977.
  • *#Nelson, T.F., and #Ward, C.P. Diffusion ordered spectroscopy (DOSY) for rapid and facile determination of consumer plastic molecular weight. 2023. Analytical Chemistry. 95, 22, 8560–8568.
  • Alloy, M., Finch, B., Ward, C.P., Redman, A., Bejarano, A., Barron, M. Recommendations for Improving Testing Protocols of Studies Examining the Photo-induced Toxicity of Petroleum and Polycyclic Aromatic Compounds. 2023. Aquatic Toxicology.
  • Chin, Y.P., McKnight, D.M., D’Andrilli, J., Brooks, N., Cawley, K., Guerard, J.E., Perdue, M., Stedmon, C.A., Tratnyek, P., Westerhoff, P., Wozniak, A., Bloom, P., Foreman, C., Gabor, R., Hamdi, J., Hanson, B., Hozalski, R., Kellerman, A., McKay, G., Reckhow, D., Remucal, C., Silverman, V., Spencer, R., Ward, C.P., and Xin, D. 2023. Identification of Next Generation International Humic Substances Society Reference Materials for Advancing the Understanding of the Role of Natural Organic Matter in the Anthropocene. Aquatic Sciences. 85, 1, 32.


  • #Sutherland, K.M., Johnston, D.T., Hemingway, J.D., Wankel, S.D., and #Ward, C.P. 2022. Revised Microbial and Photochemical Triple-Oxygen Isotope Effects Improve Marine Gross Oxygen Production Estimates. PNAS Nexus. 1, 5, pgac233.
  • *Walsh, A.N., *Mazzotta, M., *Nelson, T.F., Reddy, C.M., and Ward C.P. 2022. Synergy between Sunlight, Titanium Dioxide, and Microbes Enhances Cellulose Diacetate Degradation in the Ocean. Environmental Science & Technology. 56, 19, 13810-13819.
  • James, B.D., de Vos, A., Aluwihare, L., Youngs, S., Ward, C.P., Nelson, R.K., Michel, A.P.M., Hahm, M.E., and Reddy C.M. Divergent Forms of Pyroplastic: Lessons Learned from the M/V X-Press Pearl Ship Fire. ACS Environmental AU. 2, 5, 467-479
  • Koehler, B., Powers, L.C., Cory, R.M., Einarsdóttir, K., Gu, Y. Tranvik, L.J., Vähätalo, A.V., Ward, C.P., Miller, W.L. Inter-laboratory differences in the apparent quantum yield for the photochemical production of dissolved inorganic carbon in inland waters, and implications for photochemical rate modeling. Limnology & Oceanography: Methods. 20, 6, 320-337.
  • Berger, C.A., Ward, C.P., Karchner, S. I., Nelson, R.K., Reddy, C.M., Hahn, M.E., Tarrant, A.M. 2022. Nematostella vectensis exhibits an enhanced molecular stress response upon co-exposure to weathered oil and UV radiation. Marine Environmental Research. 175, 105569.
  • *Freeman, D.H. & Ward, C.P. Sunlight-driven dissolution is a major fate of oil at sea. Science Advances. 8, eabl7605.
  • *#Mazzotta, M.G., Reddy, C.M., & #Ward, C.P. Rapid Degradation of Cellulose Diacetate by Marine Microbes. Environmental Science & Technology Letters. 9, 1, 37-41.
  • de Vos, A., Aluwihare, L., Youngs, S., DiBenedetto, M., Ward, C.P., Michel, A., Colson, B., *Mazzotta, M., *Walsh, A., Nelson, R., Reddy, C., & James, B. 2021. The M/V X-Press Pearl nurdle spill: Contamination of burnt and unburnt nurdles along Sri Lanka’s beaches. ACS Environmental AU. 2, 2, 128–135.


  • *Walsh, A.N., Reddy, C.M., Niles, S.F., McKenna, A.M., Hansel, C.M., & Ward, C.P. Plastic Formulation is an Emerging Control of its Photochemical Fate in the Ocean. Environmental Science and Technology. 55, 18, 12383-12392.
  • *#Nelson, T.F., Reddy, C. M., and Ward, C. P. Product Formulation Controls the Impact of Biofouling on Consumer Plastic Photochemical Fate in the Ocean.  Environmental Science and Technology. 55, 13, 8898-8907.
  • Ward, C.P., *Bowen, J.C., *Freeman, D.H, and Sharpless, C.M. Rapid and Reproducible Characterization of the Wavelength Dependence of Aquatic Photochemical Reactions Using Light Emitting Diodes. 2021. Environmental Science & Technology Letters. 8, 437-442.
  • Xu, L., Roberts, M., Elder, K., Kurz, M., McNichol, A., Reddy, C., Ward, C.P., *Hanke, U. Radiocarbon in dissolved organic carbon by UV oxidation: procedures and blank characterization at NOSAMS. 2021. Radiocarbon. 63, 357-374.


  • *Nalven, S.G., Ward, C.P., Payet, J.P., Cory, R.M., Kling, G.W., Sharpton, T.J., Sullivan, C.M., & Crump, B.C. Experimental metatranscriptomics reveals the costs and benefits of dissolved organic matter photo-alteration for freshwater microbes. 2020. Environmental Microbiology. 22, 3505-3521
  • Ward, C.P. & ­Reddy, C.M. We need better data about the environmental persistence of plastic goods. 2020. Proceedings of the National Academies of Sciences. 26, 14618-14621.
  • Ward, C.P., Reddy, C.M., Overton, E.B. Why sunlight matters for marine oil spills. 2020. EOS, 101.
  • #Ward, C.P. & #Overton, E.B. How the 2010 Deepwater Horizon spill reshaped our understanding of crude oil photochemical weathering at sea: a past, present, and future perspective. 2020. Environmental Sciences: Processes & Impacts. 22, 1125-1138.
  • #Ward, C. P. & #Cory, R. M. Assessing the prevalence, products, and pathways of dissolved organic matter partial photochemical oxidation in arctic surface waters. 2020. Environmental Sciences: Processes & Impacts. 22, 1214-1223.


  • Ward, C.P., Armstrong, C.J., *Walsh, A.N., *Jackson, J.J. & Reddy, C.M. Sunlight converts polystyrene into carbon dioxide and dissolved organic carbon. 2019. Environmental Science & Technology Letters, 6, 669-674.
  • Ward, C.P., Sharpless, C.M., Valentine, D.L., Aeppli, C., *Sutherland, K.M., Wankel, S.D. & Reddy, C.M. Oxygen isotopes (δ18O) trace photochemical hydrocarbon oxidation at the sea surface. 2019. Geophysical Research Letters, 12, 6745-6754.


  • Gibson, C., Hatton, P.J., Bird, J., Nadelhoffer, K., Ward, C.P., Stark, R. and Filley, T., 2018. Interacting Controls of Pyrolysis Temperature and Plant Taxa on the Degradability of PyOM in Fire-Prone Northern Temperate Forest Soil. Soil Systems2(3).
  • Aeppli, C., Swarthout, R., O’Neil, G., Katz, S., Ward, C.P., Nelson, R., Sharpless, C., & Reddy, C.M. How persistent and bioavailable are oxygenated Deepwater Horizon oil transformation products? 2018. Environmental Science & Technology, 52, 7250-7258
  • Collins, J. R., Fredricks, H. F., Diaz, J. M., Bowman, J. S., Ward, C. P., Moreno, C. M., Longnecker, K., Marchetti, A., Hansel, C. M., Ducklow, H. W., & Van Mooy, B. A. S. The diverse products and biogeochemical significance of lipid photooxidation in coastal surface waters of West Antarctica. 2018. Geochimica et Cosmochimica Acta, 232, 244-264.
  • Ward, C. P., *Armstrong, C. J., Conmy, R. N., French-McCay, D. P., & Reddy, C. M. Photochemical Oxidation of Oil Reduced the Effectiveness of Aerial Dispersants Applied in Response to the Deepwater Horizon Spill. Environmental Science & Technology Letters, 5, 226-231.
  • Ward, C.P., Sharpless, C.M., Aeppli, C., French-McCay, D.P., Valentine, D.L., Rodgers, R. P., Gosselin, K.M., Nelson, R.K., & Reddy, C.M. Partial photochemical oxidation was a dominant fate of Deepwater Horizon surface oil. 2018. Environmental Science & Technology, 52 (4), 1797-1805.

2017 and earlier

  • Ward, C. P., Nalven, S.G., Crump, B. C., Kling, G. W., & Cory, R. M. Photochemical alteration of dissolved organic carbon draining permafrost soils shifts microbial metabolic pathways and stimulates respiration. 2017. Nature Communications, 8, 1-8.
  • Ward, C. P. & Cory, R. M. Complete and partial photo-oxidation of dissolved organic matter draining permafrost soils. 2016. Environmental Science & Technology, 50, 3545-3553.
  • Ward, C. P. & Cory, R. M. Chemical composition of dissolved organic matter draining permafrost soils. 2015. Geochemica et Cosmochimica Acta, 167, 63-79.
  • Cory, R. M., Ward, C. P., Crump, B. C., & Kling, G. W. Sunlight controls water column processing of carbon in arctic fresh waters. 2014. Science, 345, 925-928.
  • Ward, C. P., Sleighter, R. L., Hatcher, P. G., & Cory, R. M. Insights into the complete and partial photooxidation of black carbon in surface waters. 2014. Environmental Science: Processes & Impacts, 16, 721-731.
  • Hakala, J. A., Fimmen, R. L., Chin, Y. P., Agrawal, S. G., & Ward, C. P. Assessment of the geochemical reactivity of Fe-DOM complexes in wetland sediment pore waters using a nitroaromatic probe compound. 2014. Geochimica et Cosmochimica Acta, 73, 1382-1393.