Toxic impacts of Diclofenac and Triclosan induced in the clams Ruditapes philippinarum and Ruditapes decussatus under different climate change scenarios

31st European Society for Comparative Biochemistry and Physiology (ESCPB), Shifting Biological Landscapes: from molecules to mechanisms, 9-12 September 2018, Porto, PortugalThe present study aimed to assess the effects caused by an non-steroidal inflammatory drug, Diclofenac, and an antimicrobial and antifungal agent, Triclosan, in the clams Ruditapes philippinarum and Ruditapes decussatus, and to evaluate if the impacts induced were dependent on pH and temperature. Initially organisms were exposed for 30 days at two different temperature and pH (control: pH 8.0, 17ºC; test condition: pH 7.7, 20ºC) in the absence of drugs (experimental period I) followed by a 7 days exposure under the former same physical parameters but in the absence or presence of the drugs (at 1 µg/L of each contaminant, experimental period II). Biochemical responses comprising oxidative stress and metabolic capacity biomarkers were evaluated in clams after both experimental periods. The results obtained showed that under control pH and temperature, R. philippinarum individuals exposed to both pharmaceuticals presented higher lipid peroxidation and enhanced antioxidant activities compared to non-contaminated clams. When exposed to low pH and high temperature a similar response was observed in contaminanted specimens, but, in this case clams strongly increased their metabolic activities probably to fight the stress caused by the combination of both physical and chemical stressors. R. decussatus exposed to pH and temperature control conditions increased their cellular damages and antioxidant defenses when exposed to the drugs, and these same clams under low pH and high temperature showed limited oxidative stress impacts. Overall, both species presented identical responses to Diclofenac and Triclosan, although R. decussatus seemed to be less impacted by these drugs when under low pH and high temperaturePeer Reviewe