The Effect of Global Warming and Acidification on PAHs Bioaccumulation in Pearl Oyster Pinctada Radiate

Abstract

Warming and acidification are expected impact of climate change that will affect marine areas in the future. These areas are, furthermore, vulnerable to strong anthropogenic stresses such as chemical pollutants. Nevertheless, the consequences of both stressors for marine ecosystems and organisms are still unidentified. The present study aims to examine, for the first time, the effect of temperature and CO2 pressure increase on bioaccumulation of phenanthrene as a PAHs model in four tissues, gills, digestive gland, muscle and mantle of a commercially important pearl oyster Pinctada radiata. Oysters were exposed to various combination of the ambient temperature and pH currently measured in Persian Gulf (T = 24 ºC and pH = 8.1) and the expected ocean warming and acidification (T = 28 ºC and pH = 7.6), as well as proper PhE concentration (0.8 ng.l− 1) during 28 days. In all exposures, higher PhE contents were observed under hypercapnia and warming condition in the digestive gland and gills, followed by the mantle and muscle. Generally, the results visibly reveal that longer exposure period led to promote PhE bioaccumulation in all tissues under ocean warming and acidification environment which was time-dependent pattern of PhE accumulation in P.radiata. Present-day PhE environmental concentrations, which combined with ocean warming and acidification, may lead to rigorous interruption of physiological functions can be extra threatened the ecological fitness of pearl oysters.