Carbon sequestration reduced by the interference of nanoplastics on copper bioavailability

• Published in: Journal of hazardous materials 2024-04, Vol.468, p.133841, Article 133841
• Main Authors: Du, Yanting, Huang, Qianyan, Li, Shunxing, Cai, Minggang, Liu, Fengjiao, Huang, Xuguang, Zheng, Fengying, Lin, Luxiu
• Format: Article
• Language: English
• Subjects: Algal photosynthesis; Biological Availability; Carbon Sequestration; Chlorella; Copper; Copper bioavailability; Diatoms; Ecosystem; Microplastics; Phytoplankton; Plastics; Polystyrene; Polystyrenes; Risk assessment; Water Pollutants, Chemical
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2024.133841

Microplastics (MPs) have been recognized as a serious new pollutant, especially nanoplastics (NPs) pose a greater threat to marine ecosystem than larger MPs. Within these ecosystems, phytoplankton serve as the foundational primary producers, playing a critical role in carbon sequestration. Copper (Cu), a vital cofactor for both photosynthesis and respiration in phytoplankton, directly influences their capacity to regulate atmospheric carbon. Therefore, we assessed the impact of NPs on Cu bioavailability and carbon sequestration capacity. The results showed that polystyrene nanoplastics (PS-NPs) could inhibit the growth of Thalassiosira weissflogii (a commonly used model marine diatom) and Chlorella pyrenoidosa (a standard strain of green algae). The concentration of Cu uptake by algae has a significant negative correlation with COPT1 (a Cu uptake protein), but positive with P-ATPase (a Cu efflux protein). Interestingly, PS-NPs exposure could reduce Cu uptake and carbon Cu sequestration capacity of algae, i.e., when the concentration of PS-NPs increases by 1 mg/L, the concentration of fixed carbon dioxide decreases by 0.0023 ppm. This provides a new perspective to reveal the influence mechanisms of PS-NPs on the relationship between Cu biogeochemical cycling and carbon source and sink. [Display omitted] •PS-NPs exposure reduces copper uptake and carbon sequestration capacity of algae.•PS-NPs can inhibit the growth of T. weissflogii and C. pyrenoidosa.•CO2 sequestration decreases by 0.0023 ppm when NPs exposure increases by 1 mg/L.•Cu uptake is negative with COPT1, but positive with P-ATPase.•The relationship between Cu bioavailability and carbon sequestration is revealed.