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Title: Effects of soluble copper and copper oxide nanoparticle exposure on the immune system of mussels, Mytilus galloprovincialis

Copper and copper oxide nanomaterials (nCuO) can enter the marine environment negatively impacting mussels, an environmental and commercially relevant organism. We analyzed the effects on the immune system of adult mussels exposed to soluble copper (CuSO4, 20‐50 μg/L) or nCuO (100‐450 μg/L). CuSO4caused significant copper accumulation in gills and cell‐free hemolymph, while nCuO caused cell damage to gills and significant copper accumulation in hemocytes, the most abundant cells in the hemolymph. Both sources of copper caused cellular toxicity in hemocytes by increasing reactive oxygen species production and lysosome abundance, and decreasing multi‐drug resistance transporter activity. Though hemocyte abundance was not affected, theirin‐vitrophagocytic activity decreased, explaining the slight (but not statistically significant) increase in bacterial proliferation in mussels exposed to the pathogenic bacteriaVibrio tubiashiifollowing copper exposure. Thus, exposure to non‐lethal concentrations of CuSO4or nCuO can potentially increase mussel susceptibility to bacterial infections.

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Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Environmental Toxicology
Page Range / eLocation ID:
p. 294-302
Medium: X
Sponsoring Org:
National Science Foundation
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