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Bisphenol A is an endocrine disrupting compound widely used in the production of polycarbonate plastics and epoxy resins. It is ubiquitously present in the environment, mostly in aquatic environments, with consequent risks to the health of aquatic organisms and humans. In the present study, we analysed the cytogenetic effects of bisphenol A on human lymphocytes using in vitro chromosomal aberrations and micronuclei assays. Lymphocyte cultures were exposed to five different concentrations of BP-A (0.20, 0.10, 0.05, 0.02 and 0.01 μg/mL) for 24 h (for chromosomal aberrations test) and 48 h (for micronuclei test). The concentration of 0.05 µg/mL represents the reference dose established by United States Environmental Protection Agency (US EPA); 0.02 μg/mL represents the higher concentration of unconjugated BP-A found in human serum and 0.01 μg/mL represents the tolerable daily intake established by European Union. Data obtained from both assays showed significant genotoxic effects of the bisphenol A at concentrations of 0.20, 0.10 and 0.05 μg/mL, whereas at the concentration of 0.02 μg/mL, we observed only a significant increase in the micronuclei frequency. Finally, at the concentration of 0.01 μg/mL, no cytogenetic effects were observed, indicating this latter as a more tolerable concentration for human health with respect to 0.05 μg/mL, the reference dose established by US EPA. [ABSTRACT FROM AUTHOR]

According to sex allocation theory, hermaphrodites allocate a fixed amount of resources to their male and female functions, and the proportion of resources invested in each sex depends on the mating group size. Measures of trade-offs between male and female functions are usually made directly by estimating the number of gametes or the size of the gonads. In this study, we focused on the effect of social conditions (i.e. mating opportunities) on the expression of some morphological traits and on their plasticity in the protandrous simultaneously hermaphroditeOphryotrocha diadema. We investigated whether inO. diademathe morphological traits, which are dimorphic inOphryotrochadioecious species – upper-jaw size, prostomium size, body size and number of rosette glands − are plastic when they respond to variations in social conditions and whether variations in these traits are associated with variations in male and/or female reproductive success. Plasticity of the traits was analysed during both the juvenile and the adult phases in order to check whether phenotypic plasticity is limited to the developmental phase or can be manifested throughout the whole lifespan of the animals. Our results showed that the number of rosette glands, the upper-jaw size and the prostomium size are traits that are plastic inO. diadema. Indeed, the number and size of these traits changed according to the variation of social conditions. However, we found no association between the plastic morphological traits and male or female reproductive success. [ABSTRACT FROM AUTHOR]