Hidrológiai Közlöny 1989 (69. évfolyam)

2. szám - Andrik Péter: A Giardia lamblia terjedése ivóvíz útján. Irodalmi áttekintés. III. rész. A kórokozó viselkedése fertőtlenítőszerekkel szemben

98 HIDROLÓGIAI KÖZLÖNY 1989. 69. ÉVF., 2. SzAM (1) The Giardia cysts persist for extended periods of time in water. Viability (and thus the contamination potential) increases at low water temperatures between 0 and 10 °C (Fig. 1 and Table 7); (2) The inactivation kinetics of Giardia cysts in the case of chlorine and ozone is described by Watson's equation C -l' — k, so that the product C •t ' of disinfectant concentration C and exposure time t' related to %-age inactivation expresses the re­sistance of the cyst at given temperature and pH; (3 ) The Giardia cysts are extremely resistant to chlorine (Tables 2 and 3) and cannot be destroyed by the conventional methods of water chlorination. The effects of chlorine are reduced by low temperature and higher pH (Figs. 2 and 3); (4) Ozone is more effective in inactivating the cysts than chlorine, but the ozone concentration adjusted to destroying bacteria and viruses must be raised, just as the time of exposure (Tables 4 and 5). Ozone disinfection is less sensitive to (pH) and tem­perature than chlorination (Figs. 5. and fí). (5) The Giardia cysts are resistent to UV irradiation (Fig. "). Some disinfectants applicable to small water volumes are, however, effective in destroying the cysts; (6) Since the resistance of the cysts to disinfectants surpasses that of the coliform (E. coli) used as indicators of water quality, the problem of indicating safely the Giardia cysts aries. Indicator microorganisms would be needed, the resistance of which is comparable to the cysts. Keywords: Giardia lamblia, water borne epidemics, water disinfection, water quality indicators PRODROM. 2~ SB J!-.. 1 Tom. Ill e A'.i: , La pin I'm , de Flu/nine Danubii , item, Fussilii'ai - Al inh ra lwsx , A4i. ta l­lor vai , Civitatilws <JbTontanis Hvncaria. crejcentium; Forma:, Spceics, Produ&ioncs, tn Ate diu tn Adferuntur. Primum , Habetur, Difcurfus qt/idarn Proccrntalis ; DEPARTIBVS, Eundcm ALVEVM DANVBII, ( nifi, DE RIP IS, id multb vcrius dicatur ;) Material it er Coiißituentibus. Qua, Nobis, Tunc, Vcl, Tenet, Arenojx, Glareoß ; Vcl, in Gcncrc,Lapide£. ILtdcmque , Lapide<e , aut, Sta bili E i D E W lege, conftantcr Inherent es, aut,Cafualitcr Advent. Qua: Coitßanter ac pcrpctim Inb<ereant , Illas, Radicibus iiiis indidem conncxas;(Sicuti in Ripis , feu Partibus, Adonti/ojis: ) Advents; Qualcs,Soluta£Íunt,acMobilcs;a reinotiorib. Locisilluc j dcvc&as;aut,inLoco Vbi exiltunt, qualiD epener dt.is; Rcputantcs. ///«€£„ fub-dividuntur,Nobis,itcrum, in Mobiles , vcl, Jgnobiles. GUrcoJ<£ \ five, de Silice , feu Muco-, Iílo, Aqtico-Tcrrcltri , Duro, Rigíüo, Coloribus Varicgato: quandoquc ctiam, Ramcntis(ut Anr't^) I Pretiofis, Fcccundatce. Arenof<e\ Qu x, (i n t,au tMoilcs,fcu , Dijfolu biles- aut, Confiflentes. Et, Mol/es-, utpotc, Terrarum Conglutinationcs; lint, qua:inAquis G 2 dilabantur:

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