Oxidative stress and energy metabolic response of Isochrysis galbana induced by different types of pristine and aging microplastics and their leachates

Fanmeng Meng; Ziqi Ni; Liju Tan; Peining Cai; Jiangtao Wang

doi:10.1016/j.chemosphere.2023.140755

Oxidative stress and energy metabolic response of Isochrysis galbana induced by different types of pristine and aging microplastics and their leachates

Chemosphere. 2024 Jan:348:140755. doi: 10.1016/j.chemosphere.2023.140755. Epub 2023 Nov 21.

Authors

Fanmeng Meng¹, Ziqi Ni¹, Liju Tan¹, Peining Cai¹, Jiangtao Wang²

Affiliations

¹ Key Laboratory of Marine Chemistry Theory and Technology of the Ministry of Education, Ocean University of China, Qingdao, 266100, China.
² Key Laboratory of Marine Chemistry Theory and Technology of the Ministry of Education, Ocean University of China, Qingdao, 266100, China. Electronic address: jtwang@ouc.edu.cn.

PMID: 37995978
DOI: 10.1016/j.chemosphere.2023.140755

Abstract

The aging process and leachate composition of different types of MPs (PS, PS-NH₂, PS-COOH and PMMA) with a particle size of 1.0 μm were characterized, and marine microalgae Isochrysis galbana OA3011(I. galbana) was used as test organism to investigate the 96 h toxic effects of MPs before and after aging as well as leachate exposure. Except for polymethyl methacrylate (PMMA), all other tested microplastics showed significant aggregation in seawater, which increased with the presence of surface amino and carboxyl groups, in addition, the increase in polymer dispersibility index (PDI) values after aging reflected more severe aggregation. Fourier transform infrared spectrometer (FTIR) showed that the surface amino groups were shed during the aging of PS-NH₂, which can likewise be demonstrated by the change in surface electric potential from positive to negative before and after aging. PMMA, due to the addition of plasticizers (HEHP and DIBP detected in high concentration) and its own structure, has stronger resistance to aging than the other three microplastics, and no significant aging phenomenon occurs. As for I. galbana, growth inhibition, oxidative stress and energy metabolism were tested after exposure to different microplastics and their leachate. It was found that high concentrations of A-PS had a greater negative impact on I. galbana, while the toxic effects of PS-NH₂ and PS-COOH on I. galbana behaved in a diametrically opposite way before and after aging compared to PS with the inhibitory effect decreasing after aging, which was caused by the shedding of surface groups. As for PMMA, the differences in the toxic effects on microalgae before and after aging were not significant. The inhibitory effect of low concentrations of PAEs (Phthalate acid esters) in the leachate of PS-COOH on I. galbana was not significant, and the stronger inhibitory effect of 4 d L-PS-NH₂ was presumed to be the shedding of positively charged groups.

Keywords: Energy metabolism; Isochrysis galbana; Leachate; Oxidative stress; Pristine/aging microplastics.

MeSH terms

Haptophyta*
Microplastics / toxicity
Oxidative Stress
Plastics / toxicity
Polymethyl Methacrylate / pharmacology
Polystyrenes / toxicity
Water Pollutants, Chemical* / toxicity

Substances

Microplastics
Plastics
Polymethyl Methacrylate
Polystyrenes
Water Pollutants, Chemical