Effects of ocean acidification and polystyrene microplastics on the oysters Crassostrea gigas: an integrated biomarker and metabolomic approach

Highlights

• Exposure to SPS-MPs alone can cause stronger oxidative stress than LPS-MPs.
• Exposure to OA can inhibit antioxidant enzyme activity and increase clearance rate.
• Antagonistic effects were mainly occurred between MPs and OA.
• The strongest toxic effect was found in combined exposure of SPS-MPs and OA.
• Energy and antioxidant-related metabolites were altered after combined exposure.

Abstract

The adverse impacts of microplastics (MPs) or ocean acidification (OA) on mollusks have been widely reported, however, little is known about their combined effects on mollusks. The oysters Crassostrea gigas were exposed to two sizes of polystyrene MPs with 1 × 10⁴ particles/L (small polystyrene MPs (SPS-MPs): 6 μm, large polystyrene MPs (LPS-MPs): 50–60 μm) at two pH levels (7.7 and 8.1) for 14 days. The antagonistic effects between MPs and OA on oysters were mainly observed. Single SPS-MPs exposure can induce CAT enzyme activity and LPO level in gills, while LPS-MPs exposure alone can increase PGK and PEPCK gene expression in digestive glands. Ocean acidification can increase clearance rate and inhibit antioxidant enzyme activity, whereas combined exposure of OA and SPS-MPs can affect the metabolomic profile of digestive glands. This study emphasized that the potential toxic effects of MPs under the scene of climate change should be concerned.

Du Y., Teng J., Zhao J., Ren J., Ma H., Zhang T., Xia B., Sun S. & Wang Q., 2024. Effects of ocean acidification and polystyrene microplastics on the oysters Crassostrea gigas: an integrated biomarker and metabolomic approach. Marine Environmental Research 196: 106434. doi: 10.1016/j.marenvres.2024.106434. Article.

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