Oxidative stress induced by titanium dioxide nanoparticles increases under seawater acidification in the thick shell mussel Mytilus coruscus

• Biochemical responses of the mussel Mytflrn coruscus exposed to different concentrations of titanium dioxide nanoparticles (nano-Ti0(2)) (0, 2.5, 10mgL(-1)) and two pH levels (pH 8.1 and pH 7.3) for 14 days. Mussel responses were also investigated after a 7 days recovery period (pH 8.1 and no nanoparticle). Exposure to nanoTi0(2) led changes in antioxidant indexes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH)), biotransformation enzyme activity (GST) and malondialdehyde level (MDA) in gills and digestive glands. An increase in MDA level and a decrease in SOD and GSH activities were observed in gill of mussels exposed to 10 mg L-n1 nano-TiO2. This effect was more severe in mussels kept at pH 7.3 as compared to pH 8.1. A different response was observed in the digestive gland as SOD, CAT and GSH levels increased in mussels exposed to nano-TiO2. These contrasting results in digestive glands and gills were only evident at high concentration of nano-TiO2 and low pH. A 7 days recovery period was not sufficient to fully restore SOD, GPx, GST, GSH and MDA levels to levels before exposure to nano-TiO2 and low pH. Overall, our results confirmed that seawater acidification modulates effects of nanoparticles in mussels, and that gills are more sensitive to these stressors as compared with digestive glands.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

Keyword

Nano-TiO2

pH

Gill

Digestive gland

Biochemical responses

trout oncorhynchus-mykiss

carp cyprinus-carpio

fresh-water fish

crassostrea-virginica

tio2 nanoparticles

aquatic environment

ocean

acidification

physiological energetics

engineered nanoparticles

ruditapes-philippinarum

Environmental Sciences & Ecology

Marine & Freshwater Biology

Toxicology

Publication and Content Type

ref (subject category)

art (subject category)