Diplodon chilensis 6 Sewage pollution enzyme activity 6 mollusc 6 morphometry 6 pollution effect 6 Antioxidant defenses 4 Bacteria (microorganisms) 4 Coliform bacteria 4 Escherichia coli 4 Oxidative stress 4 antioxidant 4 coliform bacterium 4 freshwater environment 4 growth 4 laboratory method 4 oxidation 4 pollution exposure 4 sewage 4 Allochthonous organic matter 2 Anthropogenic impact 2 Argentina 2 Bivalvia 2 Freshwater bivalves 2 Growth rates 2 Lacar Lake 2 Neuquen 2 Patagonia 2 Population parameters 2 abundance 2