ZAGARESE Horacio Ernesto
The implications of solar UV radiation exposure for fish and fisheries. Fish and Fisheries
Fish And Fisheries
Año: 2001 vol. 2 p. 250 - 260
Ultraviolet radiation (UVR) possesses three important properties that combine tomake it a potent environmental force. These include the potential to induce damage:UVR carries more energy per photon than any other wavelength reaching the Earth’ssurface. Such highly energetic photons are known to damage many biologicalmolecules, such as DNA and proteins. In addition, they can initiate a series of redoxreactions to form reactive oxygen species (ROS), which cause oxidative stress to cellsand tissues. The second property is ubiquity: owing to their dependence on light, primaryproducers and most visual predators, such as fish, are also necessarily exposedto damaging levels of UVR. Thirdly, the combined effect of UVR and additional environmentalfactors may result in synergistic effects, such as the photoactivation of organicpollutants and photosensitisation. In natural environments, the concentration of dissolvedorganic matter (DOM) and habitat depth are the two main factors controllingthe degree of UVR exposure experienced by fish. Additional factors include vegetationcoverage, particulate materials in suspension, pH and hydrological characteristics,and site location (latitude, elevation). The range of potential effects on fish includesdirect DNA damage resulting in embryo and larval mortality, and adult and juvenilesunburn, as well as indirect oxidative stress, phototoxicity and photosensitisation.