Metal accumulation, biochemical and behavioral responses on the Mediterranean clams Ruditapes decussatus exposed to two photocatalyst nanocomposites (TiO2 NPs and AuTiO2NPs)

Rethinking Nano‐TiO2 Safety: Overview of Toxic Effects in Humans and Aquatic Animals

“…[111] Accumulation of Ti was found during exposure to waterborne nano-TiO 2 in all major organs of the bivalves indicating bio-distribution within the organism. [111,112] Oxidative Damage: Oxidative stress is a hallmark of nano-TiO 2 toxicity in mollusks as shown by elevated production of ROS, upregulation of antioxidant enzymes and accumulation of oxidative lesions. Upregulation of antioxidant enzymes (including SOD, CAT, and glutathione-S-transferase) was found in the Mediterranean clam Ruditapes decussatus and the mussels Mytilus galloprovincialis and Mytilus coruscus exposed to nano-TiO 2 , [112][113][114][115] albeit in some species this response was tissue-specific.…”

“…[111,112] Oxidative Damage: Oxidative stress is a hallmark of nano-TiO 2 toxicity in mollusks as shown by elevated production of ROS, upregulation of antioxidant enzymes and accumulation of oxidative lesions. Upregulation of antioxidant enzymes (including SOD, CAT, and glutathione-S-transferase) was found in the Mediterranean clam Ruditapes decussatus and the mussels Mytilus galloprovincialis and Mytilus coruscus exposed to nano-TiO 2 , [112][113][114][115] albeit in some species this response was tissue-specific. [114,115] In the freshwater mussel Unio tumidus, exposure to nano-TiO 2 resulted in elevated levels of ROS, depletion of GSH and activation of SOD.…”

“…[116] Increased lipid peroxidation (indicated by MDA accumulation) was found in the nano-TiO 2 exposed clams R. decussatus, C. fluminea, oysters Crassostrea virginica, and abalone Haliotis diversicolor . [86,102,112,117] The intensity of oxidative stress responses of mollusks exposed to nano-TiO 2 appears to depend on the size of nano-TiO 2 . Thus, in the mussel Unio tumidus exposure to 75 nm nano-TiO 2 (100 µg L −1 for 14 days) suppressed the SOD activity in the digestive glands.…”

“…[116] In R. decussatus exposure to 12.5 nm nano-TiO 2 (100 µg L −1 for 14 days) elevated the SOD level in the digestive glands. [112] Similarly, following exposure to 55 nm nano-TiO 2 (1 mg L −1 ), the level of SOD in several bivalves was decreased, while exposure to 20-21nm nano-TiO 2 stimulated the SOD activity. [102,118,119] Thus, it appears that smaller nano-TiO 2 particles are stronger inducers of oxidative stress in bivalves as evidenced by a compensatory increase in the SOD activity.…”

“…[93,128] Similarly, exposure to 50 and 100 µg L −1 nano-TiO 2 decreased filtration activity of the Mediterranean clam R. decussatus. [112]…”