Assessment of Erythrocyte Nuclear Abnormalities in Oiled Spheniscus Magellanicus As a Suitable Biomarker of Genotoxicity. New Tools for Rehabilitation Centers

ROMERO, M.B.; POLIZZI, P.; BAUER, J ; CARRICAVUR, ARANTXA DOLAGARATZ; CHIODI, L.; GERPE, MARCELA

Congreso; SETAC Latin America 14th biennial meeting; 2021

Genome stability could be influenced by environmental factors;therefore, it can be used as index for an individual’s response onenvironmental impact and stress, such as pollutants. When birds areexposed to less than acutely lethal dosages, oil can cause a wide rangeof adverse effects, including hemolytic anemia, decreased nutrientabsorption and decreased immune function. Evaluation of gene andcytotoxicity is an interesting field and valuable tool in environmentaltoxicology, although few studies have been conducted in wild birds.Among the methods for the estimation of genome instability is theevaluation of erythrocyte nuclear abnormalities (ENAs), which may beuseful in field research of birds. The aim was to evaluate ENAsfrequency in oiled Magellanic penguin (Spheniscus magellanicus) asbiomarkers of genotoxicity. In addition, we assessed levels of ENAs inpenguins during rehabilitation process. Peripheral blood samples ofoiled (n=29) and rehabilitation (n=21) Magellanic penguins were takenduring 2011 and 2013 in Buenos Aires Province, Argentina. Thenumber of ENAs was scored for each blood smear in relation to 1000mature erythrocytes. Considering the total of ENAs, oiled penguins(25.38 ± 12.16) presented significantly higher levels than rehabilitationanimals (9.43 ± 5.71). In particular, oiled penguins presented highervalues of the following ENAs: tailed nucleus, budding nucleus, kidneyshaped nucleus, nucleus with cavity and unknown nuclearmalformation. No significant differences (p>0.05) were found betweengroups for micronucleus and lobed nucleus. The present studyrepresents the first approach on assessing not only the frequency of MNbut also other ENAs in S. magellanicus. The micronucleus is the mostwidely used genotoxicity marker in birds. However, micronuclei werefound in low frequency (range: 0-4) in all Magellanic penguins,indicating that the evaluation of other ENAs is a better biomarker toevaluate genotoxicity for the species. The results show that oiling belowlethal dosages produces genotoxicity in Magellanic penguin, and thatthe rehabilitation process is adequate to reverse this damage. However,although the number of ENAs decreases during rehabilitation, it is notknown what the long-term damage could be. Therefore, it is importantto record the effects of stressors such as oil for long-term comparisons.