ESS - TBIO/Rise Health - Comunicações em eventos científicos
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Percorrer ESS - TBIO/Rise Health - Comunicações em eventos científicos por autor "Barros, Piedade"
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- Chronic toxicity of valproic acid in daphnia magnaPublication . Machado, Beatriz; Prudêncio, Cristina; Ferraz, Ricardo; Barros, PiedadeEnvironmental exposure to pharmaceuticals, have negative effects on the health of ecosystems and humans and numerous pharmaceuticals have been identified on surface watersall around the world. After administration, medicines are absorbed, metabolized,and excreted to the sewer system, but many are refractory to the traditional wastewater treatment and become widely distributed in freshwater riversand lakes. Valproic acid is a short-chain fatty acid,clinically used as a broad-spectrum antiepileptic drug, in neurological diseases, whose adverse effects in aquatic organisms are not fully studied. Daphnia magnaisa planktonic crustacean found in lakes and ponds and is one of the most used organisms in aquatic toxicology studies. The adverse effects of pharmaceuticals in Daphni ahave consequences in all the ecosystem. The aim of this study is to evaluate the influence of valproic acid in the reproduction of Daphnia magna. The chronic toxicity study had a duration of 21 days. It was evaluated the effect of five different concentrations of valproic acid(0,4 mg/L, 0,6 mg/L, 0,8 mg/L, 1,0 mg/L and 1,2 mg/L). The parameters evaluated were age at first, second and third posture; the number and mortality of juveniles of each posture. Valproic acid affected the age of the first posture in all the concentrations, it is notice able a delay comparatively to the control. In relation to the juveniles, all concentrations of valproic acid induced aborted eggs, and this number was higher at the highest concentrations (1,0 mg/L and 1,2 mg/L). The control didn’t have any aborted eggs. At the highest concentrations, juvenile mortality was higher,and postures were smaller than the control. Valproic acid interfere with the reproduction of Daphnia magna, causing a delay in reproduction and affecting the number and viability of the offspring.
- Ecotoxicity of valproic acid in Lemna minorPublication . Machado, Beatriz; Prudêncio, Cristina; Ferraz, Ricardo; Barros, PiedadeThe water pollution represents one of the most serious ecological challenges. Over the last years the use and consumption of pharmaceuticals has increased,and this is reflected in the rise of water contamination. Many drugs cannot be efficiently removed by wastewater treatment and ended up being released into the aquatic environment. Valproic acid is an anticonvulsive and mood stabilizer medication that has been found in the aquatic environment. Although some effects of this drug on small mammals and fish are known, its ecotoxicity in plants has not yet been evaluated. Lemnaminor is widely used as a bioindicator of water quality. This aquatic macrophyte has been applied for remediation studies and has shown effective results. The aim of this study is to study the ecotoxicity of valproic acid on the growth of Lemna minor. Lemna minor was exposed to six different concentrations of valproic acid for 7 days. During this time the number of fronds was analyzed. After the test some parameters were evaluated: area of fronds, root length and chlorophylls content. The chlorophylls were analyzed by spectrophotometry. At the higher concentration (0,1 mg/L) of valproic acid, the number of fronds was significantly lower than the control. Also, chlorophyll content was lower at 0,05 mg/L and 0,1 mg/Lfor chlorophyll a, b and carotenoids and at 0,025mg/L; 0,05mg/L and0,1mg/L for total chlorophyll. The rootlength was significantly lower at the higher concentrations(0,025mg/L; 0,05mg/L and 0,1mg/L), comparatively to the control. The fronds area didn’t show any significant difference when compared to the control. Valproic acid influenced the number of fronds,length of the root and concentration of chlorophylls and at the higher concentrations it is notable a significant inhibitory effect.