Chronic exposure to low-dose radiation at Chernobyl favours adaptation to oxidative stress in birds

1. Ionizing radiation produces oxidative stress, but organisms can adapt to their exposure with physiological adaptive responses. However, the role of radioadaptive responses in wild populations remains poorly known. 2. At Chernobyl, studies of birds and other taxa including humans show that chronic exposure to radiation depletes antioxidants and increases oxidative damage. Here we present analyses of levels of the most important intracellular antioxidant (i.e., glutathione, GSH), its redox status, DNA damage and body condition in 16 species of birds exposed to radiation at Chernobyl. We use an approach that allows considering the individual bird as the sampling unit while controlling for phylogenetic effects, thus increasing the statistical power by avoiding the use of species means as done for most previous comparative studies. 3. As a consequence, we found a pattern radically different from previous studies in wild populations, showing that GSH levels and body condition increased, an...