Seasonal Liza aurata tissue-specific DNA integrity in a multi-contaminated coastal lagoon (Ria de Aveiro, Portugal)

Abstract

In this study, the DNA integrity of golden grey mullet ( Liza aurata ) collected in differently contaminated sites of a coastal lagoon, Ria de Aveiro (Portugal), was assessed, over the period of 1 year, using the DNA alkaline unwinding assay, in four different tissues (gill, kidney, liver and blood) and compared to a refer- ence site. The four tissues displayed different DNA integrity basal levels, clearly affected by seasonal fac- tors. Gill and kidney were, respectively, the most and least sensitive tissues. All sites demonstrated the capacity to interfere with DNA integrity. The sites displaying the highest and lowest DNA damage capa- bility were, respectively, Barra (subject to naval traffic) and Vagos (contaminated with polycyclic aro- matic hydrocarbons). In terms of seasonal variability, autumn seems to be the more critical season (more DNA damage) unlike summer when no DNA damage was found in any tissue. Data recommend the continued monitoring of this aquatic system.