Profiling the hidden chemicals in biodegradable mulch films
Methodologically, the project uses controlled laboratory experiments on commercially available biodegradable mulch films and conventional polyethylene mulch films, analyzed with a high-resolution py-GC-Orbitrap-MS platform to generate additive “fingerprints” before and after degradation. The workflow includes a double-shot strategy: first, thermal desorption to capture volatile and semi-volatile additives, and second, flash pyrolysis to characterize polymer signatures, lower-abundance additives, additive-derived compounds, and small degradation products.
Films will be sampled at baseline and at multiple time points during accelerated UV weathering to quantify chemical change over time. Core metrics include the number and identity of detectable additives in each film type, relative or absolute concentrations of priority compounds, persistence or disappearance of additive signals during weathering, formation of new transformation products, and the number of compounds flagged for targeted follow-up based on ecotoxicological relevance. The project’s dataset will therefore consist of a comparative chemical profile for each purchased mulch film, plus a time-resolved weathering dataset linking film type, additive composition, and degradation stage. These data will support three main analytical questions: which additives or additive-related compounds are present in biodegradable versus polyethylene films, how those profiles change under UV exposure, and which compounds warrant targeted quantification using ecotoxicity screening such as the USEPA ECOTOX database. Immediate next steps are to purchase a representative set of market-available mulch films, establish baseline chemical fingerprints for all films, run the controlled UV weathering experiment with repeated sampling, and then integrate film chemistry and weathering profiles into a final comparative dataset. From there, the most concerning additives can move into targeted quantification to determine concentrations and assess their likely contribution to soil ecotoxicity.
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Harvard University is a comprehensive private research university in Cambridge and Boston, recognized for intensive, cross-disciplinary research and education. Industry engages through an integrated innovation ecosystem with shared core facilities, corporate-sponsored research, and incubator space in Allston. Affiliated teaching hospitals in the Longwood Medical Area enable clinical collaboration and translation, while proximity to Kendall Square places partners in a dense R&D corridor. Research is supported by major federal agencies such as the NIH, NSF, DOE and DARPA, as well as philanthropic and corporate sponsors. A dedicated technology transfer office manages IP, licensing, and startup formation and streamlines agreements for corporate collaborations.
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