Morphological changes and biochemical reaction of Ulva rigida in response to the toxic effect of bisphenol A under experimental conditions

The large-scale worldwide production and consumption of bisphenol A (BPA) has resulted in the ubiquitous presence of this chemical in aquatic ecosystems. Primary producers such as marine macroalgae can be suc-cessfully used for monitoring in order to determine the environmental risk from organic pollutants. The article is based on new experimental data obtained by the authors in the study of the sensitivity of the green marine benthic algae Ulva rigida to the impact of various concentrations of BPA was conducted. Exposure to BPA led to structural and functional changes in the Ulva samples: growth rate, cell size, and photosynthetic pigment content. In concentrations from 40 to 100 mg/L, a destructive effect from BPA on the Ulva was observable within 24-48 h, taking the form of complete chloroplast discoloration occurring in 100% of its cells. A dose-dependent stimu-lating effect of low concentrations of BPA on the growth of Ulva was also noted. As compared with the control, the disc area of Ulva in a medium with a BPA concentration of 0.1 mg/L almost doubled within 30 days, while at 5 mg/L, it increased by only 21%. Changes in chlorophyll a and b content were observed in the first hours of BPA exposure. The pigment content in the Ulva decreased under the influence of BPA both at an impact concentration of 100 mg/L and a low concentration of 0.01 mg/L. The sensitivity to bisphenol A contamination of the U. rigida in different regions may vary.