Microplastics found in the human body have been reported to compromise tissue integrity, damage organs, and contribute to inflammation and carcinogenesis. Recent research indicates that microplastics also reduce photosynthetic efficiency by approximately 10% across terrestrial, aquatic, and freshwater ecosystems. This reduction has significant implications, potentially leading to an annual loss of up to 360 million metric tons of crops and nearly 24 million tons of seafood, which could impact food availability for roughly 123 million adults. In response to these concerns, this pilot study employed a floating disc assay to quantitatively assess the infiltration of rigid micro- and nano thermo-amino particles (MNPPs) into the foliage of four representative vegetable species: Basella alba (Malabar Spinach), Capsicum chinense (Habanero), Brassica rapa (Bok Choy), and Phaseolus vulgaris (String Beans). The crops were grown organically in Amityville, New York, an area marked by substantial industrial activity. The primary aim was to determine whether rainfall facilitates the entry of MNPPs, ranging in size from 1000 nanometers to 5 micrometers, into leaf tissue through photosynthesis, respiration, and cuticular absorption. Both adaxial and abaxial surfaces of leaf discs were analyzed before and after exposure to MNPPs using a LABOMED CxL clinical microscope. The findings indicate that MNPPs can penetrate leaf structures during both photoperiod (photosynthesis) and scotoperiod (respiration), irrespective of whether the stomata are closed. These findings reveal a previously unidentified route for plastic pollutants to enter the human food chain.
References
[1]
Dokl, M., Copot, A., Krajnc, D., Fan, Y.V., Vujanović, A., Aviso, K.B., et al. (2024) Global Projections of Plastic Use, End-of-Life Fate and Potential Changes in Consumption, Reduction, Recycling and Replacement with Bioplastics to 2050. Sustainable ProductionandConsumption, 51, 498-518. https://doi.org/10.1016/j.spc.2024.09.025
[2]
Qin, M. (2024) What Are Nanoplastics? An Engineer Explains Concerns about Particles Too Small to See. The Conversation. https://theconversation.com/what-are-nanoplastics-an-engineer-explains-concerns-about-particles-too-small-to-see-225791
[3]
Li, Y., Liu, X., Shinde, S., Wang, J. and Zhang, P. (2021) Impacts of Micro-and Nanoplastics on Photosynthesis Activities of Photoautotrophs: A Mini-Review. FrontiersinMicrobiology, 12, Article ID: 773226. https://doi.org/10.3389/fmicb.2021.773226
[4]
Kannan, K. and Vimalkumar, K. (2021) A Review of Human Exposure to Microplastics and Insights into Microplastics as Obesogens. Frontiers in Endocrinology, 12, Article ID: 724989. https://doi.org/10.3389/fendo.2021.724989
[5]
Smith, C.A., Drichko, N., Lorenzo, M. and Pramanik, S. (2025) Contaminants of Emerging Concern on Microplastics Found in the Chrysaora Chesapeakei of the Patuxent River, Chesapeake Bay, Md. Microplastics, 4, Article 32. https://doi.org/10.3390/microplastics4020032
[6]
Bowley, J., Baker-Austin, C., Porter, A., Hartnell, R. and Lewis, C. (2021) Oceanic Hitchhikers—Assessing Pathogen Risks from Marine Microplastic. TrendsinMicrobiology, 29, 107-116. https://doi.org/10.1016/j.tim.2020.06.011
[7]
Jia, L., Liu, L., Zhang, Y., Fu, W., Liu, X., Wang, Q., et al. (2023) Microplastic Stress in Plants: Effects on Plant Growth and Their Remediations. FrontiersinPlantScience, 14, Article 1226484. https://doi.org/10.3389/fpls.2023.1226484
[8]
European Commission, Joint Research Centre, Geiss, O., El Hadri, H., Giechaskiel, B., Al Wasif Ruiz, T., Putaud, J. and Barrero, J. (2024) Micro-and Nanoplastics in the Air: Sources, Transport & Analytical Methods for Their Determination. Publications Office of the European Union.
[9]
Zhang, Y., Slade, J.H., Ault, A.P. and Chan, A.W.H. (2025) An Atmospheric Chemistry Perspective on Airborne Micro-and Nanoplastic Particles. EnvironmentalScience&Technology, 59, 7810-7819. https://doi.org/10.1021/acs.est.5c03264
[10]
Zhang, X., Yin, Z., Xiang, S., Yan, H. and Tian, H. (2024) Degradation of Polymer Materials in the Environment and Its Impact on the Health of Experimental Animals: A Review. Polymers, 16, Article 2807. https://doi.org/10.3390/polym16192807
[11]
Abbas, G., Ahmed, U. and Ahmad, M.A. (2025) Impact of Microplastics on Human Health: Risks, Diseases, and Affected Body Systems. Microplastics, 4, Article 23. https://doi.org/10.3390/microplastics4020023
[12]
Roth-Nebelsick, A., Konrad, W., Ebner, M., Miranda, T., Thielen, S. and Nebelsick, J.H. (2022) When Rain Collides with Plants—Patterns and Forces of Drop Impact and How Leaves Respond to Them. JournalofExperimentalBotany, 73, 1155-1175. https://doi.org/10.1093/jxb/erac004
[13]
Carvalho, A.B., Farias, C.N., de Castro Vasconcellos, P., Fernandes, A.N., de Sales, F., Chiquetto, J.B., et al. (2025) Detection, Characteristics, and Some Influencing Factors of MPS in Rainfall. TheoreticalandAppliedClimatology, 156, Article No. 220. https://doi.org/10.1007/s00704-025-05441-y
[14]
Li, Z., Gong, X., Wang, J., Chen, Y., Liu, F., Li, H., et al. (2023) Foliar Water Uptake Improves Branch Water Potential and Photosynthetic Capacity in Calligonum Mongolicum. EcologicalIndicators, 146, Article 109825. https://doi.org/10.1016/j.ecolind.2022.109825
[15]
Li, Y., Zhang, J., Xu, L., Li, R., Zhang, R., Li, M., et al. (2025) Leaf Absorption Contributes to Accumulation of Microplastics in Plants. Nature, 641, 666-673. https://doi.org/10.1038/s41586-025-08831-4
[16]
Lian, J., Liu, W., Meng, L., Wu, J., Chao, L., Zeb, A., et al. (2021) Foliar-Applied Polystyrene Nanoplastics (PSNPs) Reduce the Growth and Nutritional Quality of Lettuce (Lactuca sativa L.). EnvironmentalPollution, 280, Article 116978. https://doi.org/10.1016/j.envpol.2021.116978
[17]
Kagawa, A. (2022) Foliar Water Uptake as a Source of Hydrogen and Oxygen in Plant Biomass. TreePhysiology, 42, 2153-2173. https://doi.org/10.1093/treephys/tpac055
[18]
Wang, Y., Li, H., Tan, F., Jin, L.N., Su, J. and Luo, C. (2025) Root and Foliar Uptake, Bidirectional Translocation, Subcellular Distribution, and Metabolism of Tire Wear Particle-Derived P-Phenylenediamines and Their Quinones in Chinese Cabbage and Bok Choy. EnvironmentalPollution, 382, Article 126737. https://doi.org/10.1016/j.envpol.2025.126737
[19]
Kimball, J. (2016) 16.2D: Gas Exchange in Plants. Biology Libre Texts. https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Biology_(Kimball)/16%3A_The_Anatomy_and_Physiology_of_Plants/16.02%3A_Plant_Physiology/16.2D%3A_Gas_Exchange_in_Plants
[20]
36.5.1: Response to Water Stress (2021) Biology LibreTexts. https://bio.libretexts.org/@go/page/75367
[21]
Harrison, E.L., Arce Cubas, L., Gray, J.E. and Hepworth, C. (2020) The Influence of Stomatal Morphology and Distribution on Photosynthetic Gas Exchange. ThePlantJournal, 101, 768-779. https://doi.org/10.1111/tpj.14560
[22]
Chaudhary, H.D., Shah, G., Bhatt, U., Singh, H. and Soni, V. (2025) Microplastics and Plant Health: A Comprehensive Review of Sources, Distribution, Toxicity, and Remediation. npjEmergingContaminants, 1, Article No. 8. https://doi.org/10.1038/s44454-025-00007-z
[23]
Vaidyanathan, T. (2025) Microplastics Are Disrupting Photosynthesis and Threatening our Food Supply. Defend Our Health. https://defendourhealth.org/blog/microplastics-are-disrupting-photosynthesis-and-threatening-our-food-supply/
[24]
Teng, L., Zhu, Y., Li, H., Song, X. and Shi, L. (2022) The Phytotoxicity of Microplastics to the Photosynthetic Performance and Transcriptome Profiling of Nicotiana Tabacum Seedlings. EcotoxicologyandEnvironmentalSafety, 231, Article 113155. https://doi.org/10.1016/j.ecoenv.2021.113155
[25]
Tanjil, R.H., Islam, M.S., Islam, Z., Roy, S., Nahian, S. and Salam, A. (2025) Atmospheric Microplastic Pollution in Textile Industrial Areas: Source, Composition, and Health Risk Assessment. BulletinofEnvironmentalContaminationandToxicology, 114, Article 51. https://doi.org/10.1007/s00128-025-04021-0
[26]
Hernández-Fernández, J., Puello-Polo, E. and Trilleras, J. (2022) Characterization of Microplastics in Total Atmospheric Deposition Sampling from Areas Surrounding Industrial Complexes in Northwestern Colombia. Sustainability, 14, Article 13613. https://doi.org/10.3390/su142013613
[27]
González-Valenzuela, L., Renard, J., Depège-Fargeix, N. and Ingram, G. (2023) The Plant Cuticle. CurrentBiology, 33, R210-R214. https://doi.org/10.1016/j.cub.2023.01.003
[28]
Fowler, C., Marshall, R., Son, M. and Jung, S. (2024) Resonance and Damping in Drop-Cantilever Interactions. PhysicalReviewFluids, 9, Article 123605. https://doi.org/10.1103/physrevfluids.9.123605
[29]
Heinen, R.B., Ye, Q. and Chaumont, F. (2009) Role of Aquaporins in Leaf Physiology. JournalofExperimentalBotany, 60, 2971-2985. https://doi.org/10.1093/jxb/erp171
[30]
Poschenrieder, C., Fernández, J.A., Rubio, L., Pérez, L., Terés, J. and Barceló, J. (2018) Transport and Use of Bicarbonate in Plants: Current Knowledge and Challenges Ahead. InternationalJournalofMolecularSciences, 19, Article 1352. https://doi.org/10.3390/ijms19051352
[31]
Hachez, C., Milhiet, T., Heinen, R.B. and Chaumont, F. (2017) Roles of Aquaporins in Stomata. In: Chaumont, F. and Tyerman, S., Eds., Signaling and Communication in Plants, Springer International Publishing, 167-183. https://doi.org/10.1007/978-3-319-49395-4_8
[32]
Sack, L. and Scoffoni, C. (2012) Measurement of Leaf Hydraulic Conductance and Stomatal Conductance and Their Responses to Irradiance and Dehydration Using the Evaporative Flux Method (EFM). JournalofVisualizedExperiments, No. 70, e4179. https://doi.org/10.3791/4179
[33]
Ding, L., Fox, A.R. and Chaumont, F. (2024) Multifaceted Role and Regulation of Aquaporins for Efficient Stomatal Movements. Plant, Cell&Environment, 47, 3330-3343. https://doi.org/10.1111/pce.14942
[34]
Sibbernsen, E. and Mott, K.A. (2010) Stomatal Responses to Flooding of the Intercellular Air Spaces Suggest a Vapor-Phase Signal between the Mesophyll and the Guard Cells. PlantPhysiology, 153, 1435-1442. https://doi.org/10.1104/pp.110.157685
[35]
Eller, F., Jensen, K. and Reisdorff, C. (2016) Nighttime Stomatal Conductance Differs with Nutrient Availability in Two Temperate Floodplain Tree Species. TreePhysiology, 37, 428-440. https://doi.org/10.1093/treephys/tpw113
[36]
Willmer, C.M. and Fricker, M. (1996) Stomata. London Chapman & Hall.
[37]
Maity, S., Guchhait, R. and Pramanick, K. (2024) Role of Aquaporins in Micro-Plastics Accumulation in Onion Roots and the Effects of Micro-Plastics on Microtubules Stability and Organization under Heat and Salinity Stress. EnvironmentalandExperimentalBotany, 220, Article 105692. https://doi.org/10.1016/j.envexpbot.2024.105692
[38]
Xiong, D. and Nadal, M. (2020) Linking Water Relations and Hydraulics with Photosynthesis. ThePlantJournal, 101, 800-815. https://doi.org/10.1111/tpj.14595
[39]
Sloane, C. (2021) The Effects of Rainwater on Plants. Sciencing.com. https://www.sciencing.com/the-effects-of-rain-water-on-plants-12390760/
[40]
Australian Academy of Science (2012) Plants in Action. A Resource for Teachers and Students of Plant Science. Australian Academy of Science.
[41]
Li, L., Luo, Y., Li, R., Zhou, Q., Peijnenburg, W.J.G.M., Yin, N., et al. (2020) Effective Uptake of Submicrometre Plastics by Crop Plants via a Crack-Entry Mode. NatureSustainability, 3, 929-937. https://doi.org/10.1038/s41893-020-0567-9
[42]
Luo, Y., Li, L., Feng, Y., Li, R., Yang, J., Peijnenburg, W.J.G.M., et al. (2022) Quantitative Tracing of Uptake and Transport of Submicrometre Plastics in Crop Plants Using Lanthanide Chelates as a Dual-Functional Tracer. NatureNanotechnology, 17, 424-431. https://doi.org/10.1038/s41565-021-01063-3
[43]
Giorgetti, L., Spanò, C., Muccifora, S., Bottega, S., Barbieri, F., Bellani, L., et al. (2020) Exploring the Interaction between Polystyrene Nanoplastics and Allium Cepa during Germination: Internalization in Root Cells, Induction of Toxicity and Oxidative Stress. PlantPhysiologyandBiochemistry, 149, 170-177. https://doi.org/10.1016/j.plaphy.2020.02.014
Zhou, C., Lu, C., Mai, L., Bao, L., Liu, L. and Zeng, E.Y. (2021) Response of Rice (Oryza sativa L.) Roots to Nanoplastic Treatment at Seedling Stage. Journal of HazardousMaterials, 401, Article 123412. https://doi.org/10.1016/j.jhazmat.2020.123412
[46]
Quilliam, R.S., Pow, C.J., Shilla, D.J., Mwesiga, J.J., Shilla, D.A. and Woodford, L. (2023) Microplastics in Agriculture—A Potential Novel Mechanism for the Delivery of Human Pathogens onto Crops. FrontiersinPlantScience, 14, Article ID: 1152419. https://doi.org/10.3389/fpls.2023.1152419
[47]
Pawłowicz, I. and Masajada, K. (2019) Aquaporins as a Link between Water Relations and Photosynthetic Pathway in Abiotic Stress Tolerance in Plants. Gene, 687, 166-172. https://doi.org/10.1016/j.gene.2018.11.031
[48]
Ishfaq, M., Shakoor, N., Rillig, M.C. and Geilfus, C. (2025) Airborne Microplastics in Leaves and Food Safety Risks. TrendsinPlantScience, 30, 1063-1065. https://doi.org/10.1016/j.tplants.2025.05.012
[49]
Luo, D., Chu, X., Wu, Y., Wang, Z., Liao, Z., Ji, X., et al. (2024) Micro-and Nano-Plastics in the Atmosphere: A Review of Occurrence, Properties and Human Health Risks. JournalofHazardousMaterials, 465, Article 133412. https://doi.org/10.1016/j.jhazmat.2023.133412
