Pharmaceutical and personal care products (PPCPs) have been recognized as emerging aquatic pollutants. Even if their presence in aquatic ecosystems is well-known, the information regarding the effects towards aquatic non-target organisms is inadequate and is often related to a limited number of conventional model species. The present chapter highlights the suitability of the zebra mussel (Dreissena polymorpha) as a non-conventional model organism for aquatic ecotoxicology to investigate the toxicity of emerging pollutants. We investigated the adverse effects due to 96 hours in vivo exposure to environmental concentrations (1 nM) of diverse PPCPs, namely triclosan (TCS), trimethoprim (TMP), ibuprofen (IBU), diclofenac (DCF) and paracetamol (PCM), on the zebra mussel by using a suite of biomarkers. The analysis of biomarker responses and their integration into a biomarker response index (BRI) showed that TCS was the most toxic for the zebra mussel molecule among the tested PPCPs, followed by TMP, IBU, DCF and PCM. Our findings demonstrate that the sensitivity of the zebra mussel in response to low PPCP concentrations confers to this bivalve the status of a reliable model organism for aquatic ecotoxicology, suggesting that it should be routinely used to evaluate the toxicity of emerging aquatic pollutants.