@article{smith_zambrano_ankeny_daystar_pires_pawlak_venditti_2024, title={Aquatic Aerobic Biodegradation of Commonly Flushed Materials in Aerobic Wastewater Treatment Plant Solids, Seawater, and Lakewater}, volume={19}, ISSN={["1930-2126"]}, url={http://dx.doi.org/10.15376/biores.19.1.1150-1164}, DOI={10.15376/biores.19.1.1150-1164}, abstractNote={Microfibers and microplastics originating from wastewater treatment plant (WWTP) effluents are significant pollutants in freshwater sources and marine environments. This research investigated the biodegradation of cotton microfibers generated from bleached cotton jersey knit fabric and commercially available flushable wipes, polypropylene-based (PP) nonwoven wipes containing a cellulose component, and tissue paper. Biodegradation was tested in wastewater treatment plants (WWTP) solids, seawater, and lakewater according to the ISO 14852 and ASTM D6691 standard methods in an ECHO respirometer. Degradation experiments continued until a plateau in CO2 emissions was reached, and the final biodegradation extent was calculated relative to the theoretical CO2 produced based on elemental analysis. The results showed that the cotton and other cellulosic materials/components biodegrade to a great extent, as expected for all conditions, whereas the PP did not degrade. In general, for the cellulose polypropylene composite wipes, the cellulose biodegraded readily; the presence of the PP did not hinder the cellulose biodegradation.}, number={1}, journal={BIORESOURCES}, author={Smith, Madilynn M. and Zambrano, Marielis and Ankeny, Mary and Daystar, Jesse and Pires, Steven and Pawlak, Joel and Venditti, Richard A.}, year={2024}, month={Feb}, pages={1150–1164} }
 @article{kwon_zambrano_pawlak_ford_venditti_2024, title={Aquatic biodegradation of poly(β-hydroxybutyrate) in polylactic acid and maleic anhydride blended fibers}, volume={31}, ISSN={["1572-8935"]}, DOI={10.1007/s10965-024-03930-8}, number={4}, journal={JOURNAL OF POLYMER RESEARCH}, author={Kwon, Soojin and Zambrano, Marielis C. and Pawlak, Joel J. and Ford, Ericka and Venditti, Richard A.}, year={2024}, month={Apr} }
 @article{kwon_zambrano_venditti_pawlak_2023, title={Aerobic aquatic biodegradation of bio-based and biodegradable polymers: Kinetic modeling and key factors for biodegradability}, volume={185}, ISSN={["1879-0208"]}, url={https://doi.org/10.1016/j.ibiod.2023.105671}, DOI={10.1016/j.ibiod.2023.105671}, abstractNote={With the increasing concern about plastic waste, numerous efforts have been made to find substitutes for existing non-biodegradable synthetic polymers. Bio-based and/or purported petroleum-based biodegradable polymers are considered probable plastic replacement candidates. However, the durability of non-biodegradable plastic is a key feature of plastics. Thus, a balance must be achieved between biodegradation and environmental material stability. The objective of this study is to determine the impact of crystallinity, molecular chemistry, and hydrophilicity on the rate of aquatic biodegradation of biobased plastic materials. In the present study, twelve bio-based/purported biodegradable materials were investigated under aerobic aquatic biodegradation conditions for 56 days by tracking oxygen consumption. Crystallinity, hydrophobicity, chemistry, and chemical structure were varied to understand potential means for controlling the rate of biodegradation. The biodegradation kinetics were analyzed and discussed, relating to the characteristics of polymers. Polyvinyl alcohol (PVA), Chitosan, Rayon, Polyhydroxy-butyrate-co-valerate (PHBV), PHBH, and Polybutylene succinate (PBS) showed the biodegradation extents over 70% at 56 days. Cellulose acetates (CAs) and Polylactic acid (PLA) showed biodegradation extent lower than 20%. The chemistry of the polymer backbone chain, substituent structure, and degree of substitution were the dominant factors affecting biodegradation. The crystallinity of the polyesters had a negative correlation with the initial biodegradation rate and the ultimate biodegradation of polyesters, and the hydrophobicity of the polymers delayed the initiation of biodegradation. The aerobic aquatic biodegradation results related to the polymer characteristics are useful for product designers and environmental scientists to understand the fate of these polymeric materials in the environment.}, journal={INTERNATIONAL BIODETERIORATION & BIODEGRADATION}, author={Kwon, Soojin and Zambrano, Marielis C. and Venditti, Richard A. and Pawlak, Joel J.}, year={2023}, month={Nov} }
 @article{kwon_zambrano_pawlak_ford_venditti_2023, title={Aquatic Biodegradation of Poly(beta-Hydroxybutyrate) and Polypropylene Blends with Compatibilizer and the Generation of Micro- and Nano-Plastics on Biodegradation}, volume={4}, ISSN={["1572-8919"]}, DOI={10.1007/s10924-023-02832-y}, journal={JOURNAL OF POLYMERS AND THE ENVIRONMENT}, author={Kwon, Soojin and Zambrano, Marielis C. C. and Pawlak, Joel J. J. and Ford, Ericka and Venditti, Richard A. A.}, year={2023}, month={Apr} }
 @misc{parrilla-lahoz_mahebadevan_kauta_zambrano_pawlak_venditti_reina_duyar_2022, title={Materials challenges and opportunities to address growing micro/ nanoplastics pollution: a review of thermochemical upcycling}, volume={20}, ISSN={["2589-2347"]}, DOI={10.1016/j.mtsust.2022.100200}, abstractNote={Micro/nanoplastics have sparked attention in recent years due to their widespread presence in the environment. Currently, several waste valorization approaches are under development in order to upcycle micro/nanoplastics. Thermal conversion technologies such as pyrolysis, gasification, liquefaction, or hydrothermal carbonization can yield high-value solid products, oil, and gases from plastics waste. The common thermal conversion technologies investigated focus on maximizing the production of oil and gases (such as H2 and CH4) for use as fuel. Except for hydrogen, when these products are used to generate energy, the carbon emissions generated are comparable to those produced by traditional fossil fuels. Herein, we present a review of the current efforts to capture and convert plastic waste into valuable products with an emphasis on identifying the need to develop processes specifically for micro/nanoplastics while also preventing the release of CO2 emissions. We identify the development of efficient catalytic materials as a critical research need for achieving economically viable thermochemical conversion of micro/nanoplastics.}, journal={MATERIALS TODAY SUSTAINABILITY}, author={Parrilla-Lahoz, S. and Mahebadevan, S. and Kauta, M. and Zambrano, M. C. and Pawlak, J. J. and Venditti, R. A. and Reina, T. R. and Duyar, M. S.}, year={2022}, month={Dec} }
 @article{kwon_zambrano_venditti_frazier_zambrano_gonzalez_pawlak_2022, title={Microfiber shedding from nonwoven materials including wipes and meltblown nonwovens in air and water environments}, volume={4}, ISSN={["1614-7499"]}, DOI={10.1007/s11356-022-20053-z}, abstractNote={Nonwoven products are widely used in disposable products, such as wipes, diapers, and masks. Microfibers shed from these products in the aquatic and air environment have not been fully described. In the present study, 15 commercial single-use nonwoven products (wipes) and 16 meltblown nonwoven materials produced in a pilot plant were investigated regarding their microfiber generation in aquatic and air environments and compared to selected textile materials and paper tissue materials. Microfibers shed in water were studied using a Launder Ometer equipment (1-65 mg of microfibers per gram material), and microfibers shed in air were evaluated using a dusting testing machine that shakes a piece of the nonwoven back and forth (~ 4 mg of microfibers per gram material). The raw materials and bonding technologies affected the microfiber generation both in water and air conditions. When the commercial nonwovens contained less natural cellulosic fibers, less microfibers were generated. Bonding with hydroentangling and/or double bonding by two different bonding methods could improve the resistance to microfiber generation. Meltblown nonwoven fabrics generated fewer microfibers compared to the other commercial nonwovens studied here, and the manufacturing factors, such as DCD (die-to-collector distance) and air flow rate, affected the tendency of microfiber generation. The results suggest that it is possible to control the tendency of microfiber shedding through the choice of operating parameters during nonwoven manufacturing processes.}, journal={ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH}, author={Kwon, Soojin and Zambrano, Marielis C. and Venditti, Richard A. and Frazier, Ryen and Zambrano, Franklin and Gonzalez, Ronalds W. and Pawlak, Joel J.}, year={2022}, month={Apr} }
 @article{kwon_zambrano_pawlak_venditti_2021, title={Effect of lignocellulosic fiber composition on the aquatic biodegradation of wood pulps and the isolated cellulose, hemicellulose and lignin components: kinetic modelling of the biodegradation process}, volume={28}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-021-03680-6}, DOI={10.1007/s10570-021-03680-6}, number={5}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Kwon, Soojin and Zambrano, Marielis C. and Pawlak, Joel J. and Venditti, Richard A.}, year={2021}, month={Feb}, pages={2863–2877} }
 @article{salam_zambrano_venditti_pawlak_2021, title={Hemicellulose and Starch Citrate Chitosan Foam Adsorbents for Removal of Arsenic and Other Heavy Metals from Contaminated Water}, volume={16}, ISSN={["1930-2126"]}, DOI={10.15376/biores.16.3.5628-5645}, abstractNote={Arsenic and other heavy metal contaminants in water are a significant global health threat. In this study, low-cost, sulfur-free, sustainable, water-insoluble materials with heavy metal remediation properties were produced from renewable resources such as starch, xylan, citric acid, and chitosan. Synthesized starch citrate-chitosan (SCC) foam and xylan citrate-chitosan (XCC) foam were flexible, porous, and elastic. The foams’ arsenic uptake in water was significantly greater than five different commercial metal remediating agents. The mercury and lead uptakes with the synthesized foams were similar to the performance of a commercial sulfur-based product, SorbaTech 450 (ST450). However, the cadmium and selenium uptakes were comparatively lower. The complexation of arsenic with oxygen and nitrogen of the SCC foam was shown with time-of-flight secondary ion mass spectrometry (TOF-SIMS). The XCC foam was also shown to adsorb potassium iodide (KI) at a similar rate to sodium chloride. This may be used to remediate water contaminated with radioactive materials, such as iodine 131.}, number={3}, journal={BIORESOURCES}, author={Salam, Abdus and Zambrano, Marielis C. and Venditti, Richard A. and Pawlak, Joel}, year={2021}, month={Aug}, pages={5628–5645} }
 @article{zambrano_pawlak_daystar_ankeny_venditti_2021, title={Impact of dyes and finishes on the aquatic biodegradability of cotton textile fibers and microfibers released on laundering clothes: Correlations between enzyme adsorption and activity and biodegradation rates}, volume={165}, ISSN={["1879-3363"]}, DOI={10.1016/j.marpolbul.2021.112030}, abstractNote={The presence and biodegradability of textile microfibers shed during laundering or use is an important environmental issue. In this research, the influence of common textile finishes on the persistence of cotton fibers in an aerobic aquatic environment was assessed. The biodegradation of cotton knitted fabrics with different finishes, silicone softener, durable press, water repellent, and a blue reactive dye was evaluated. The rate of biodegradation decreased with durable press and water repellant finishing treatments. In terms of the final extent of biodegradation, there was no significant difference between the samples. All samples reached more than 60% biodegradation in 102 days. The biodegradation rates were in agreement with observed trends of the same samples for cellulase mediated hydrolysis and cellulase adsorption experiments, indicating the finishes impact the initial adsorption of enzymes excreted by the microorganisms and the initial rates of biodegradation, however despite this the cellulosic material maintains its biodegradability.}, journal={MARINE POLLUTION BULLETIN}, author={Zambrano, Marielis C. and Pawlak, Joel J. and Daystar, Jesse and Ankeny, Mary and Venditti, Richard A.}, year={2021}, month={Apr} }
 @article{zambrano_pawlak_daystar_ankeny_venditti_2021, title={Impact of dyes and finishes on the microfibers released on the laundering of cotton knitted fabrics}, volume={272}, ISSN={0269-7491}, url={http://dx.doi.org/10.1016/j.envpol.2020.115998}, DOI={10.1016/j.envpol.2020.115998}, abstractNote={The influence of common textile finishes on cotton fabrics on the generation of microfibers during laundering was assessed. Microfiber release was determined to be in the range of 9000–14,000 particles per gram of cotton fabric. Cotton knitted fabrics treated with softener and durable press generate more microfibers (1.30–1.63 mg/g fabric) during laundering by mass and number than untreated fabric (0.73 mg/g fabric). The fabrics treated with softener generated the longest average microfiber length (0.86 mm), whereas durable press and water repellent treatments produced the shortest average microfiber length (0.62 and 0.63 mm, respectively). In general, the changes in the mechanical properties of the fibers and fabrics due to the finishing treatments are the main factor affecting the microfiber release. The abrasion resistance of the fabrics decreases for durable press treatments and water repellent treatments due to the brittleness in the structure originated by the crosslinking treatment. In the case of the softener treatment, the fabric surface is soft and smooth decreasing the friction coefficient between fibers favoring the fibers loosening from the textile and resulting in a high tendency for fuzz formation and microfiber release. These findings are useful for the textile industry in the design and selection of materials and treatments for the reduction of synthetic or natural microfiber shedding from textiles.}, journal={Environmental Pollution}, publisher={Elsevier BV}, author={Zambrano, Marielis C. and Pawlak, Joel J. and Daystar, Jesse and Ankeny, Mary and Venditti, Richard A.}, year={2021}, month={Mar}, pages={115998} }
 @article{zambrano_pawlak_daystar_ankeny_goller_venditti_2020, title={Aerobic biodegradation in freshwater and marine environments of textile microfibers generated in clothes laundering: Effects of cellulose and polyester-based microfibers on the microbiome}, volume={151}, ISSN={0025-326X}, url={http://dx.doi.org/10.1016/j.marpolbul.2019.110826}, DOI={10.1016/j.marpolbul.2019.110826}, abstractNote={The aerobic biodegradation of common textiles that shed microfibers during laundering was evaluated under the action of microbes found in the environment, such as lake and seawater, and activated sludge at a low concentration from a wastewater treatment plant (WWTP). Under these conditions, the biodegradation potential was the same in all the experiments: Microcrystalline Cellulose (MCC) > Cotton > Rayon > Polyester/Cotton ≫ Polyester. Nevertheless, for cotton and rayon yarns, >70% biodegradation was achieved with activated sludge at low concentration and lake water, whereas in seawater, about 50% degradation was reached. Polyester did not appreciably degrade. The biodegradation results herein indicate potential not absolutes in nature. The bacterial diversity analyses in the different biodegradation inoculums show that there are distinct bacterial communities related to the assimilation and mineralization of complex carbohydrates that were promoted with the cellulosic MCC, cotton, and rayon samples different than the polyester sample.}, journal={Marine Pollution Bulletin}, publisher={Elsevier BV}, author={Zambrano, Marielis C. and Pawlak, Joel J. and Daystar, Jesse and Ankeny, Mary and Goller, Carlos C. and Venditti, Richard A.}, year={2020}, month={Feb}, pages={110826} }
 @article{zambrano_pawlak_venditti_2020, title={Effects of Chemical and Morphological Structure on Biodegradability of Fibers, Fabrics, and Other Polymeric Materials}, volume={15}, ISSN={["1930-2126"]}, DOI={10.15376/biores.15.4.Zambrano}, abstractNote={The biodegradability of polymers depends on several factors. However, the most critical aspects are the accessibility of the structure for moisture and enzyme diffusion and the capacity of the microbes in the environment to assimilate the final monomers. The accessibility of the polymer structure to enzymes and water depends primarily on crystallinity, hydrophobicity, and the steric effects of the side groups in the polymer backbone. In general, biologically synthesized polymers are readily biodegradable in natural environments but synthetic polymers are either less biodegradable or degrade very slowly. However, such generalizations should be avoided. To understand the compatibility of biomaterials and the environment, both the disintegration step of the biodegradation process and the assimilation and mineralization of these fragments by microorganisms must be investigated. Mineralization occurs when the oligomers and monomers assimilated within the cells are converted to CO2 and H2O (aerobic), and CO2, CH4, and H2O (anaerobic). Although the disintegration of the polymeric structure limits the biodegradation rate and is most easily detected, the final pieces may accumulate in the environment if they are not fully mineralized. Such accumulation could contribute to an issue with microplastics that may be much more difficult to address than the removal of macroscopic, large polymer-based debris.}, number={4}, journal={BIORESOURCES}, author={Zambrano, Marielis C. and Pawlak, Joel J. and Venditti, Richard A.}, year={2020}, month={Nov}, pages={9786–9833} }
 @article{zambrano_pawlak_daystar_ankeny_cheng_venditti_2019, title={Microfibers generated from the laundering of cotton, rayon and polyester based fabrics and their aquatic biodegradation}, volume={142}, ISSN={0025-326X}, url={http://dx.doi.org/10.1016/j.marpolbul.2019.02.062}, DOI={10.1016/j.marpolbul.2019.02.062}, abstractNote={The effect of fiber type (cotton, polyester, and rayon), temperature, and use of detergent on the number of microfibers released during laundering of knitted fabrics were studied during accelerated laboratory washing (Launder-Ometer) and home laundering experiments. Polyester and cellulose-based fabrics all shed significant amounts of microfibers and shedding levels were increased with higher water temperature and detergent use. Cellulose-based fabrics released more microfibers (0.2–4 mg/g fabric) during accelerated laundering than polyester (0.1–1 mg/g fabric). Using well-controlled aquatic biodegradation experiments it was shown that cotton and rayon microfibers are expected to degrade in natural aquatic aerobic environments whereas polyester microfibers are expected to persist in the environment for long periods of time.}, journal={Marine Pollution Bulletin}, publisher={Elsevier BV}, author={Zambrano, Marielis C. and Pawlak, Joel J. and Daystar, Jesse and Ankeny, Mary and Cheng, Jay J. and Venditti, Richard A.}, year={2019}, month={May}, pages={394–407} }