Abstract

Polycyclic Aromatic Hydrocarbons (PAHs) are a global concern. Due to their ubiquitous presence and their impacts on organisms, PAHs have become a major threat to the health of the marine ecosystem. To assess their impacts, the use of biomarkers are useful early warning tools for biological effects detection in environmental quality studies. The present work assessed relations between muscle 17 PAHs and oxidative stress biomarkers in liver and muscle of an estuarine-resident fish: Ramnogaster arcuata. Specifically, lipid peroxidation (evaluated by thiobarbituric acid-reactive substances; TBARs), tripeptide glutathione (GSH) and glutathione S-transferase activity (GST) were determined in liver and muscle tissues. Fish were captured seasonally in Bahia Blanca estuary (BBE), an area highly impacted with one of the most important petrochemical parks of South America. The PAHs levels observed for R. arcuata were between minimally and moderately polluted (range: 5.14-340.31 ng/g w.w.), being the highest level observed in summer represented by a mixture of petrogenic and pyrolytic sources. Spearman correlation analyses showed positive correlations (p < 0.05) of total PAHs (Σ17 PAHs) with hepatic TBARs (0.66) and muscle GSH (0.62). Also, correlations with individuals PAHs were found: hepatic TBARs-anthracene (0.96), hepatic TBARs-phenanthrene (0.76), muscle GSH-anthracene (0.79), muscle GSH-naphthalene (0.72), hepatic GST-chrysene (-0.93), and hepatic GST-fluoranthene (-0.69). These results suggest that hepatic TBARs and muscle GSH could be more sensitive biomarkers to chronic pollution of complex mixtures of PAHs. On the other hand, the correlations of individual PAHs suggest that hepatic GST could be a more specific biomarker for 4-ring PAHs, since it only correlates with this group of PAHs. While both hepatic TBARs and muscle GSH could be good biomarkers for petrogenic PAHs. The results of this work increase the understanding about the oxidative stress biomarkers in response to PAHs in R. arcuata and confirms that this species is a good bioindicator of the BBE. These results could have a positive influence on future biomonitoring of estuarine areas, allowing the early detection of PAHs effects and the consequent decision-making before irreversible environmental damage occurs.