Pereira Juliana Tracz, Costa Adriana Oliveira, de Oliveira Silva Márcia Benedita, Schuchard Wagner, Osaki Silvia Cristina, de Castro Edilene Alcântara, Paulino Rosangela Clara, Soccol Vanete Thomaz
Departamento de Patologia Básica, Setor de Ciências Biológicas, Centro Politécnico, Jardim das Américas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Appl Biochem Biotechnol. 2008 Dec;151(2-3):464-73. doi: 10.1007/s12010-008-8214-3. Epub 2008 May 23.
In the present work, assays were performed to compare the efficacy of hypochlorous acid, chlorine dioxide, and ozone in the inactivation of Cryptosporidium oocyst in public water supply from Brazilian South conditions. Experiments were carried out in samples containing 2 x 10(4) oocysts/ml of C. parvum purified from feces of experimentally contaminated calves. An in vitro excystation method was used to evaluate oocysts' viability and to determine the inactivation rates of hypochlorous acid at 2 ppm, chlorine dioxide at 1, 2, and 5 ppm, and ozone at the doses of 0.18, 0.24, 0.36, 0.48, and 1.44 mg/l. By using hypochlorous acid, the maximum inactivation rate obtained was 49.04% after 120 min. Chlorine dioxide at 5 ppm inactivated 90.56% of oocysts after 90 min of contact. Ozone was the most effective product, rendering an inactivation of 100% with the concentration of 24 mg/l. Resistance of Cryptosporidium to the usual disinfectants and the need for more effective water treatments to prevent waterborne diseases in Brazil are discussed in this manuscript.
在本研究中，进行了相关试验，以比较次氯酸、二氧化氯和臭氧在巴西南部公共供水条件下对隐孢子虫卵囊的灭活效果。实验在含有从实验感染小牛粪便中纯化得到的每毫升2×10⁴个小隐孢子虫卵囊的样本中进行。采用体外脱囊方法评估卵囊的活力，并确定2 ppm次氯酸、1 ppm、2 ppm和5 ppm二氧化氯以及0.18 mg/l、0.24 mg/l、0.36 mg/l、0.48 mg/l和1.44 mg/l剂量臭氧的灭活率。使用次氯酸时，120分钟后获得的最大灭活率为49.04%。5 ppm二氧化氯接触90分钟后可灭活90.56%的卵囊。臭氧是最有效的消毒剂，浓度为24 mg/l时可实现100%的灭活率。本手稿讨论了隐孢子虫对常用消毒剂的抗性以及巴西为预防水源性疾病而进行更有效水处理的必要性。
