I'm going to have to take some chem classes to figure this out.
these reports are complements of Boomer from RC, he posted the abstracts on Paul's ozone thread.
Oxidative cell damage in Kat-sod assay of oxyhalides as inorganic disinfection by-products and their occurrence by ozonation. Ueno H; Oishi K; Sayato Y; Nakamuro K Department of Biological Sciences, 1845 N. Fairmount, Wichita State University, Wichita, Kansas 67260-0026, USA ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY (2000 Jan), 38(1), 1-6.
Abstract:
Nine oxyhalides as possible inorganic disinfection by-products were tested for oxidative cell damage by Kat-sod assay with E. coli mutant strains deficient in the active oxygen-scavenging enzymes. Chlorine dioxide, chlorite, and iodate were highly cytotoxic, whereas in the presence of cysteine, bromate (BrO3-) and metaperiodate (IO4-) showed more growth inhibition toward the superoxide dismutase-deficient strains than the wild strain. BrO3- also showed oxidative mutagenicity with cysteine or glutathione ethyl ester in S. typhimurium TA 100. To identify oxyhalides formed by ozonation of raw water containing sea water, the occurrence of ozonation by-products of bromide and iodide was investigated. The results indicate that BrO3- is toxicologically one of the most remarkable oxyhalides detectable in drinking water because IO4- was not detected in the ozonated solution of iodide, and the ozonation condition to lower BrO3- is to keep it neutral in the presence of ammonium ion.
Oxidation of Iodide and Hypoiodous Acid in the Disinfection of Natural Waters. Bichsel, Yves; von Gunten, Urs. Swiss Federal Institute for Environmental Science and Technology EAWAG, Duebendorf, Switz. Environ. Sci. Technol. (1999), 33(22), 4040-4045.
Abstract:
In aq. oxidative processes with O3, Cl, or chloramine, naturally occurring I- can easily be oxidized to HOI which can react with natural org. matter (NOM) or be further oxidized to IO3-. Such processes can be of importance for the geochem. of I and for the fate of I in industrial processes (drinking water treatment, aquacultures). Whereas IO3- is the desired sink for I in drinking waters, iodoorg. compds. (esp. CHI3) are problematic due to their taste and odor. To assess the sink for I during oxidn. of natural waters, we detd. the kinetics of several oxidn. reactions of HOI. O3, Cl, and chloramine were tested as potential oxidants. O3 oxidized both HOI and OI- (kO3+HOI = 3.6 ? 104/M-s; kO3+OI- = 1.6 ? 106/M-s) in a fast reaction. Cl species oxidized HOI by a combination of 2nd- and 3rd-order reactions (k''HOCl+HOI = 8.2/M-s; k'''HOCl+HOI = 8.3 ? 104/M2-s; kOCl-+HOI = 52/M-s). Monochloramine did not further oxidize HOI. The probability of the formation of iodoorg. compds. during drinking water disinfection therefore increases in the order O3
Modeling of nitrate and bromate in a seawater aquarium. Grguric, Gordan; Coston, Christopher J. Marine Science Program, Richard Stockton College, Pomona, NJ, USA. Water Res. (1998), 32(6), 1759-1768.
Abstract:
Closed marine systems where there is no significant primary productivity and water changes are impractical exhibit increasing nitrate concns. over time. At the Living Seas artificial seawater aquarium, nitrate concn. reached 9700mM after 5 yr of operation. Concern about potential toxic effects assocd. with a further increase led to the development of a batch denitrification system, sep. from the Main Tank of the aquarium. The system was installed in early 1991 and after 350 days of operation, nitrate concn. in the aquarium decreased to 3200mM. Two models are applied to the empirical nitrate data - one designed specifically for nitrate and one originally developed for bromate. Both models have correlations greater than 0.95 with the empirical nitrate data over the period studied. The models were used to det. the steady state nitrate concn. in the aquarium: the first model predicts 850mM, assuming no idle time between denitrification runs. The second model predicts 2300mM, with the actual idle times taken into account. Potentially toxicity and carcinogenicity of bromate has been of concern in recirculating seawater aquaria, where bromate is produced from oxidn. of bromide during ozonation. By late 1990, bromate concn. in The Living Seas reached 4.6mM. After the installation of the denitrification system, bromate concn. has been controlled by the balance between ozonation and denitrification processes. We developed a model based on the existing kinetic data regarding bromate formation during ozonation and an empirically detd. rate of bromate loss during denitrification. The model predicts a bromate concn. of 3.6mM by early 1994, in reasonable agreement with the obsd. value of 3.4mM. The eventual steady state bromate concn. predicted by the model is 0.7mM. Verification of the model with the obsd. bromate and nitrate data from The Living Seas shows that it is a useful tool for predicting concns. of redox-reactive chem. species in a closed seawater system.
In addn., empirical data from this study suggest that denitrification can be used to control bromate concns. in seawater aquaria that employ ozone for disinfection.
Physiological effect of seawater treated by ozone on Chlorella sp. Wang, Chenggang; Tang, Xiaohua; Zheng, Bo; Ma, Shen. Shandong Marine Scientific and Technical Academy, Tsingtao, Peop. Rep. China. Shuichan Xuebao (2001), 25(2), 151-155.
Abstract:
The effects of seawater treated by ozone on reprodn., chlorophyll-a content, DNA and RNA content in Chlorella sp. were studied. Meanwhile, NH4+-N, NO2--N and NO3--N content in the seawater were analyzed. The results showed as follows: a certain concn. of ozone treatment could increase reprodn. and chlorophyll-a content, but higher concn. of ozone treatment could inhibit reprodn. of Chlorella sp.; DNA content showed relative stability, RNA content was more sensitive to ozone treatment than DNA content, and ozone treatment could increase RNA content; HN4+-N and NO2--N content decreased in seawater by ozone treatment, while NO3--N content increased compared with that in control seawater.
Qualitative assay of residual oxidants in seawater and effect of several oxidants on Japanese flounder, Paralichthys olivaceus, eggs. Mimura, Gen; Nagamitu, Takako; Nagase, Toshiya; Namba, Kenji. Ebara Jitugyo Aquaculture Engineering Lab, Nakahara, Kawasaki, Kanagawa, Japan. Suisan Zoshoku (1998), 46(4), 579-587. CODEN: SUZOAV ISSN: 0371-4217.
Abstract:
An attempt was made to quantify oxidants by measuring trihalogenated methanes generated from reacting resorcin with TRO (total residual oxidants). The results showed that the residual oxidants in OPO (ozone-producted oxidants) seawater, TRC (total residual chlorine) seawater and electrolyzed seawater were mostly hypobromous acid. When seawater contg. hydrogen peroxide or povidone-iodine was treated with resorcin, no trihalomethane was detected. In addn., when NaClO was added to seawater dild. 3-30 times with distd. water, both chlorine-contg. and bromine-contg. oxidants were detected. Delayed hatching was obsd. frequently in Japanese flounder eggs exposed to OPO seawater, TRC seawater or electrolyzed seawater. Occurrence of the delayed hatching increased rapidly when the oxidant concn. increased to 2 mg O3/l or higher. No increment in dead eggs was obsd. When the eggs were exposed to seawater contg. hydrogen peroxide or povidone-iodine, few delayed hatching of eggs were found. Most of the eggs that failed to hatch died.
Acute toxicity of ozone-exposed seawater and chlorinated seawater for Japanese flounder, Paralichthys olivaceus, eggs, larvae and juveniles. Mimura, Gen; Katayama, Yasuto; Ji, Xiangrong; Xie, Jialin; Namba, Kenji. Ebara Jitsugyo Aquaculture Engineering Lab, Nakahara, Kawasaki, Kanagawa, Japan. Suisan Zoshoku (1998), 46(4), 569-578.
Abstract:
The toxic effects of exposure to ozone-exposed seawater and chlorinated seawater were investigated in eggs and larvae aged 3-15 days and juveniles aged 44 days in the setting stage of Japanese flounder, Paralichthys olivaceus. For eggs, the 50% no-hatching concn. of OPO and TRC after 1 min exposure were both about 2.2 mg O3/l. The 24-h LC50 values of OPO and TRC in larvae aged 3-15 days were both 0.02-0.05 mg O3/l. The 24-h LC50 values of OPO and TRC for juveniles aged 44 days in the setting stage were both 0.14-0.15 mg O3/l. Light microscopy of branchial tissues showed detachment of the epithelium of the secondary lamellae after exposure to OPO or TRC. SEM of branchial tissues showed cell swelling and cell destruction of the secondary lamellae after exposure to OPO or TRC. The toxicity of OPO and TRC and damage to branchial tissue caused by OPO and TRC were exactly alike.