Perfluorinated compounds in blood of Caretta caretta from the Mediterranean Sea

Perfluorinated compounds (PFCs), widely used for their hydro-oil repellent properties, are almost non-degradable in the environment; there is scientific evidence that indicate bioaccumulation. They represent a threat to many organisms, because they are toxic and are endocrine disruptors. Scientific studies have demonstrated the presence of PFCs in blood and liver samples of fish, turtles, birds and mammals of marine ecosystems in different geographical areas. The aim of this study was to determine the distribution of PFOS and PFOA in blood samples of the marine turtle Caretta caretta, using a minimally invasive sampling procedure. 49 blood samples of marine turtle, taken from several Italian marine turtle rescue centers, were analyzed. While PFOA was never detected, measurable concentrations of PFOS were found in 15 blood samples; the values show a range from 1.14 ng/g to 28.51 ng/g (wet wt.). No differences between groups of samples taken from different areas were found.     

Persistence of solar activity on small scales: Hurst analysis of time series coming from Hα flares

We calculated the Hurst exponent H for the daily averaged intensity Q of optical flares, an index which describes the solar activity. We found that H0.74±0.02 in the range of scales from about 20 days up to 450 days. This value is well beyond H= , expected for a stochastic Brownian process, thus indicating that the solar cycle could show persistence on small scales, in agreement with what has been found using other indices of the solar cycle.