Uso De Filtros De Carvão Ativado Granular Associado A Microrganismos Para Remoção De Fármacos No Tratamento De água De Abastecimento

The way of life of modern societies has originated the daily intake of pharmaceuticals and numerous other molecules of continuous use in aquatic environments, emerging compounds that brings potential risk for human health mainly due to exposure resulted from the inevitable contamination of sources of drinking water supply and its transference to the water treatment plants (WTP) where they are not removed. The use of granular activated carbon in filters proves to be a viable option for WTP, but satisfactory efficiency requires periodic regeneration of the material, burdening the treatment costs. However, it is noted that under low filtration rates, the natural colonization of filters by microorganisms — biofilm formation — may be an alternative for increasing the lifetime of carbon, as well as to decompose these complex molecules into assimilable mineral elements, thereby reintroducing them to the natural biogeochemical cycles. This study evaluated the activated carbon with biofilm as the filter media, during 24 weeks, under laboratory conditions, considering the removal of the pharmaceuticals diclofenac sodium, ibuprofen, naproxen and amoxicillin; experienced under batch system the potential of the microorganisms adhering to the filters in degrade the tested drugs, as well as phylogenetically identified the predominant microorganisms in biodegradation. The results show drug removal over 80%. It was observed the presence of the bacteria genus Bacillus, Burkholderia, Cupriavidus, Pseudomonas, Shinella and Sphingomonas. This study allows us to infer the capacity to remove pharmaceuticals by the bacteria present in the activated carbon filters, and the possible use of this technology as an alternative for control and removal of these substances in drinking water treatment. © 2016, ABES - Associacao Brasileira de Engenharia Sanitaria e Ambiental. All rights reserved.21470972

Phytoplanktonic Structure and Chemistry of the Water in the Monjolinho Reservoir (SP, Brazil) During a Cyanobacterial Bloom Episode

The composition of the phytoplankton and parameters of the water quality were studied in a tropical reservoir during cyanobacterial bloom episode. Samples were collected at two sites during October 2004. The phytoplankton community consisted of 69 taxa, distributed into 9 classes. Most taxa belonged to Cyanobacteria (17), Chlorophyceae (21), Bacillariophyceae (8), Conjugatophyceae (7), Dinophyceae (1), Chrysophyceae (4), Euglenophyceae (9), Cryptophyceae (1) and Xanthophyceae (1). Anabaena circinalis Rabenhorst ex Bornet et Flahault e Anabaena spiroides Klebahn were the dominant species. Statistical analyses revealed significant spatial variation (p < 0.05) between sampling points only for N compounds and chlorophyll a. Most limnological variables analyzed showed no significant temporal variation (p > 0.05). Cyanobacteria bloom was concomitant with the following environmental conditions, warm water temperatures (19 to 22 oC), periods of water column stability and high concentrations of N (724.9 μg.L-1) and P (90.9 μg.L-1) in the reservoir and NH4 as being the predominant nitrogen compounds. It is speculated that those conditions could play a role in the dominance of cyanobacteria

Occurrence of anatoxin-a(s) during a bloom of Anabaena crassa in a water-supply reservoir in southern Brazil

Cyanobacterial blooms and the accompanying production of cyanotoxins are a serious global problem. Toxic blooms of Anabaena species are common in lagoons and reservoirs of southern Brazil. Worldwide, species of the genus Anabaena produce the majority of the known hepatotoxins (microcystins) and neurotoxins [anatoxin-a, anatoxin-a(s), and saxitoxins]. This report links a bloom of Anabaena crassa in the Faxinal Reservoir, the main water supply for the city of Caxias do Sul (400,000 inhabitants) in southern Brazil, to the occurrence of anatoxin-a(s) in the water. During the bloom period, the reservoir was strongly stratified, with higher temperatures and a deep anoxic hypolimnion. Two methods for sample concentration (direct and complete extraction) were tested, and direct extraction of samples proved to be more efficient. Water samples collected during the bloom showed 9% acetylcholinesterase inhibition at 50 mg mL−1, corresponding to 0.61μg of anatoxin-a(s) per gram of lyophilized powder. At these concentrations, symptoms of neurotoxicity and mortality were not observed in tests with Swiss albino mice. Although the concentrations of anatoxin-a(s) in the Faxinal Reservoir were low, these results are important because this is the first record of the toxin for A. crassa. Furthermore, this cyanotoxin is not yet included in Brazilian legislation for drinking-water monitoring, because of the lack of information about toxicity levels and risk calculation for oral doses. The data presented here contribute to the basis for the future inclusion of this toxin in Brazilian legislation for drinking-water quality control, and for the development of analytical methods for this toxin