Combined effects of polyamide microplastic and sulfamethoxazole in modulating the growth and transcriptome profile of hydroponically grown rice (Oryza sativa L.)

Authors: ULLAH, ULLAH - University Of North Carolina Greensboro; FEYISSA, A., BIRUK - Oak Ridge National Laboratory; Stiles, Julia; TSZ-KI TSUI, MARTIN - University Of Hong Kong; CHOW, ALEX - The Chinese University Of Hong Kong (CUHK); Williams, Clinton; KARANFIL, TANJU - Clemson University; LIGABA-OSENA, AYALEW - University Of North Carolina Greensboro

Submitted to: Environmental Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/28/2024
Publication Date: 9/2/2024
Citation: Ullah, Ullah, Feyissa, A., Biruk, Stiles, J.F., Tsz-Ki Tsui, Martin, Chow, Alex, Williams, C.F., Karanfil, Tanju, Ligaba-Osena, Ayalew 2024. Combined effects of polyamide microplastic and sulfamethoxazole in modulating the growth and transcriptome profile of hydroponically grown rice (Oryza sativa L.). Environmental Science and Technology. 952(2024). Article 175909. https://doi.org/10.1016/j.scitotenv.2024.175909.
DOI: https://doi.org/10.1016/j.scitotenv.2024.175909

Interpretive Summary: The world's population is growing, which means we need more food and water. An alternative to help growing more food, is using recycled water from treatment plants to water crops. However, this water can contain tiny pieces of plastic and chemicals that can harm the plants. A study was done using rice plants to see how these pollutants affect them. The results showed that the pollutants slowed down the growth of the plants, made them produce less biomass, and caused stress. The study also found changes in the genes that might help them deal with stress and use nutrients. This research shows that the presence of microplastics can reduce yield.

Technical Abstract: As the global population continues to rise, the demand for food production and freshwater resources is also increasing. To address this challenge, utilizing reclaimed water from wastewater treatment plants for irrigation has been considered a viable solution to enhance food productivity. However, this practice introduces micropollutants such as microplastics (MPs) and antimicrobials (AMs) into the agroecosystem, despite reducing stress on freshwater resources. A hydroponic experiment was conducted to investigate the effects of single and combined treatment of 0.1% polyamide (PA ~15 µm) MP, and different concentrations of sulfamethoxazole (SMX), 0, 10, 50, and 150 mg/L on rice seedlings (Oryza sativa) for 12 days. The research aimed to assess the impact of these contaminants on the morphological, physiological, and biochemical parameters of the rice plants, including the activity of antioxidant enzymes like POD, MDA, SOD, and CAT. The results revealed that SMX, whether alone or in combination with PA, significantly inhibited shoot and root growth, reduced plant biomass, and affected photosynthetic pigments. Higher concentrations of SMX also led to an increase in antioxidant enzyme activity, indicating oxidative stress induced by the contaminants. The SMX content was higher in the roots compared to the shoots, and concentration of some important minerals such as iron, copper, and magnesium were reduced in roots under with SMX treatment with and without PA. RNA-seq analysis showed changes in gene expression related to stress, metabolism, and transport in response to the micropollutants. Overall, this study provides valuable insights into the potential risks posed by micropollutants on economically important crops like rice, highlighting the importance of considering the combined impacts of MPs and AMs on plants, the environment, and human health in future risk assessments and management strategies.