Persistent organic pollutants and enzyme activities in European eel (Anguilla anguilla) from Orbetello Lagoon

1 - The aim of the present study was to obtain insights into the environmental quality of Orbetello lagoon using the European eel (Anguilla anguilla) as bioindicator organism. 2 - Levels of POPs, including seven polychlorobiphenyls (PCBs) (known as markers of Aroclor 1260), three coplanar PCBs, ΣDDT (op-DDD, pp '-DDD, op-DDT, pp '-DDT, op '-DDE, pp'-DDE), hexachlorobenzene (HCB), hexachlorocyclohexane (HCH: α-HCH, β-HCH, γ-HCH, δ-HCH), polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzo-p-furans (PCDFs) and polybromodiphenylethers (PBDEs), were investigated in eel muscle to study bioaccumulation of toxic compounds. 3 - EROD MROD and UDPGT activities were measured in liver microsomal fraction to investigate eel detoxifying/metabolic capacity. 4 - Ovaries were analyzed by light microscopy to evaluate potential risk for eel reproduction. Muscle concentrations of PCBs, DDTs, pp '-DDE, HCB and HCHs were in the ng/g lipid weight (l.w.) range while coplanar PCBs were in the pg/g wet weight range. 5 - PCDD/Fs were below the detection limit. Toxic equivalents (TEQs) calculated for mono- and non-ortho PCBs were below the risk thresholds established by the European Union. 6 - EROD, MROD and UDPGT activities suggested low exposure to chemical inducers in line with the low concentrations of contaminants observed in muscle. Principal components analysis (PCA) showed a potential role of DDTs, especially pp '-DDE, in inducing EROD, MROD and UDPGT activities. 7 - All specimens analysed were females; oocytes in advanced stages of development showed normal morphology, whereas those in early stages of development showed histological anomalies. © 2009 University of Salento - SIBA