Simultaneous removal of fluoride and arsenic from well water by electrocoagulation.

The co-occurrence of fluoride and arsenic in groundwater presents a problem in many, mostly arid, regions of Latin America and the world. These pollutants cause significant health problems and are difficult to remove simultaneously from drinking water. In this study, the electrocoagulation process for the simultaneous removal of fluoride and arsenic was evaluated in well from the state of Durango, Mexico, in order to both solve the local problem and determine how to apply the method generally. Tests were carried out with different times, concentrations, initial pH values, and electric current densities, with iron and aluminum as electrode materials. The removal efficiencies in simultaneous presence were 85.68% for fluoride and approximately 100% for arsenic. The final concentrations for both pollutants were below the drinking water limits established by the World Health Organization (WHO) and Mexican regulations. The optimum conditions of the electrocoagulation process found were a current density of 4.5 mA/cm2, an initial pH of 5, and a treatment time of 15 min, considering initial fluoride and arsenic concentrations of 5 mg/L and 80 µg/L, respectively.

Distinct neurobehavioral dysfunction based on the timing of developmental binge-like alcohol exposure.

Gestational exposure to alcohol can result in long-lasting behavioral deficiencies generally described as fetal alcohol spectrum disorder (FASD). FASD-modeled rodent studies of acute ethanol exposure typically select one developmental window to simulate a specific context equivalent of human embryogenesis, and study consequences of ethanol exposure within that particular developmental epoch. Exposure timing is likely a large determinant in the neurobehavioral consequence of early ethanol exposure, as each brain region is variably susceptible to ethanol cytotoxicity and has unique sensitive periods in their development. We made a parallel comparison of the long-term effects of single-day binge ethanol at either embryonic day 8 (E8) or postnatal day 7 (P7) in male and female mice, and here demonstrate the differential long-term impacts on neuroanatomy, behavior and in vivo electrophysiology of two systems with very different developmental trajectories. The significant long-term differences in odor-evoked activity, local circuit inhibition, and spontaneous coherence between brain regions in the olfacto-hippocampal pathway that were found as a result of developmental ethanol exposure, varied based on insult timing. Long-term effects on cell proliferation and interneuron cell density were also found to vary by insult timing as well as by region. Finally, spatial memory performance and object exploration were affected in P7-exposed mice, but not E8-exposed mice. Our physiology and behavioral results are conceptually coherent with the neuroanatomical data attained from these same mice. Our results recognize both variable and shared effects of ethanol exposure timing on long-term circuit function and their supported behavior.