Phototoxicity of pyrene affects benthic algae and bacteria from the arctic

• Published in: Environmental Science & Technology
• Main Authors: Petersen, Dorthe G, Reichenberg, Fredrik, Dahllöf, Ingela
• Format: Article in Journal/Newspaper
• Language: English
• Published: The American Chemical Society (ACS) 2008
• Subjects: Analytical Chemistry; Arctic
• Online Access: https://lup.lub.lu.se/record/1196912; https://doi.org/10.1021/es071854n

Phototoxicity of polycyclic aromatic hydrocarbons (PAHs) in the Arctic is important to study since the future PAH load is likely to increase. In combination with the increased UV-Iight penetration due to ozone layer thinning, phototoxicity may be a potential problem for arctic areas. The aim of this study was to evaluate effects of pyrene and phototoxicity of pyrene on natural algae and bacteria from. arctic sediments. Sediments from a shallow-water marine bay were spiked with different pyrene concentrations. Microcosms containing the sediment were incubated under three light regimes, natural sunlight with UV-light, natural sunlight without W-light, and dark. Significant effects were evident at low pyrene concentrations, particularly in presence of W-light, indicating phototoxicity. The microalgae were especially sensitive to the phototoxicity of pyrene. Already at the lowest pyrene concentration (C-free: 4 nM) algal C-14-incorporation and chlorophyll a content were reduced. The toxic effects of pyrene on the microalgae probably led to the release of organic matter. In agreement with this, bacterial activity increased at high pyrene concentrations indicated by increased oxygen consumption and increased release of inorganic N and P from the sediment. This study indicates that phototoxicity of PAHs may be relevant for sediment communities from shallow marine arctic areas at environmentally relevant pyrene concentrations.