{Provides extensive details} "Chlorine dioxide irritates the nose, throat, trachea and bronchi at very low concentrations (less than 5 ppm) resulting in breathlessness, wheezing and coughing. Higher concentrations can cause inflammation in the upper respiratory tract, bronchial spasms and difficulty in breathing. A potentially fatal accumulation of fluid in the lungs (pulmonary edema) could occur. Symptoms of pulmonary edema (chest pain and shortness of breath) can be delayed for up to 24 or 48 hours after exposure. Long-term respiratory effects (e.g. sensitivity to respiratory irritants, chronic nasal inflammation, asthma, pulmonary emphysema and spastic bronchitis) have been noted in workers accidentally exposed to unspecified concentrations for a short time"

****!!!****!!!!!*** 2001 {Tests on rats} "The acute toxicity and build-up toxicity of mice were tested by Horn's method and accumulation coefficient method, and the acute toxicity and accumulation toxicity of mice were studied through 90-day feeding tests on rats Subchronic toxicity of ClO2 and its by-products ClO-2 and ClO-3 mixed aqueous solutions, including weight gain, food utilization, hematological indicators, serum biochemical indicators, statistical analysis of liver (kidney) /weight ratio variance, and pathological histology microscopy of liver (kidney). The results showed that the ClO2 aqueous solution of 2 76.5mg/l, the NaClO2 and NaClO3 aqueous solution of 2 0 mg/l and the mixed aqueous solution with a total concentration of 553mg/lClO2 were all actual non-toxic aqueous solutions. 2 76.5mg/l ClO2, 2 0 0mg/l NaClO2 and NaClO3 aqueous solutions are also aqueous solutions without significant build-up; ClO2 mixture had no significant effect on weight gain and food utilization in rats (p 0 .0 5); There was no effect on rat hematological indicators such as white blood cell count (WBC) and hemoglobin (Hb) (p 0 .0 5); Tests of glutat-propylene transaminase (ALT), total protein (TP), albumin (ALB) and globulin (GLO) showed no significant difference between the control group and the high-dose group (p 0 .0 5); The liver-to-body ratio (%) and renal ratio (%) of rats in each test group and control group were analyzed by variance, and there was no significant difference between the groups (p 0 .0 5); Pathological histological examination results showed that no lesions were seen in the liver and kidney tissues of the test groups and control groups."

****Results: Deaths and severe skin damage

Data on Acute Exposure Guideline Levels (AEGLs). Chlorine Dioxide Acute Exposure Guideline Levels for Selected Airborne Chemicals, Volume 5, 2007.

****!!!**** 1982 "The primary products resulting from ClO2 disinfection of waters are chlorites (ClO2-) and chlorates (ClO3-). Studies in rats revealed that ClO2 is converted to chloride (Cl-), ClO2- and ClO3-. ClO2- and ClO3- are excreted as Cl-, ClO2- and Cl-, ClO2-, ClO3-, respectively. Radioactivity was rapidly absorbed from the gastrointestinal tract following the administration of 36ClO2 orally, and the half-life for the elimination of 36Cl from the rat was 44 hr, corresponding to a rate constant of 0.016/hr. After 72 hr, radioactivity was highest in plasma, followed by kidney, lung, and stomach. 36Cl in plasma reached a peak at 2 hr and 1 hr after oral administration of 36ClO2- and 36ClO3-, respectively. 36Cl excretion was greatest 24 hr after the administration of 36ClO3-, but in the case of 36ClO2-, the excretion probably represented saturation of the biotransformation and excretion pathway. A low activity in packed cells compared to plasma was detected in chlorate ingestion, rather than an even distribution in chlorite treatment. Chloroform determinations in rat blood after one year indicated that chloroform was significantly higher than control in the 100 and 1000 mg/l. ClO2 groups. However, no significant values were observed in the 1 or 10 mg/l. ClO2 and ClO2 metabolites groups. ClO2 and its metabolites are eliminated from the body more rapidly than chlorine, and they do not appear to increase trihalomethane concentrations at low dosages."

"The efficacy and safety of UC-1 were evaluated. The antimicrobial activity was more than 98.2% reduction when UC-1 concentrations were 5 and 20 ppm for bacteria and fungi, respectively. The half maximal inhibitory concentrations (IC50) of H1N1, influenza virus B/TW/71718/04, and EV71 were 84.65 ± 0.64, 95.91 ± 11.61, and 46.39 ± 1.97 ppm, respectively. A 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test revealed that the cell viability of mouse lung fibroblast L929 cells was 93.7% at a 200 ppm UC-1 concentration that is over that anticipated in routine use. Moreover, 50 ppm UC-1 showed no significant symptoms in a rabbit ocular irritation test. In an inhalation toxicity test, treatment with 20 ppm UC-1 for 24 h showed no abnormality and no mortality in clinical symptoms and normal functioning of the lung and other organs. A ClO2 concentration of up to 40 ppm in drinking water did not show any toxicity in a subchronic oral toxicity test. Herein, UC-1 showed favorable disinfection activity and a higher safety profile tendency than in previous reports."

***********Wide variety of toxicity results from studies.***DECOMP (GAS) TO CHLORIC ACID, CHLORINE, & OXYGEN IN HOT WATER *"Two adults ingested 250 ml of chlorine dioxide in water containing concn of 40 mg/l. Within 5 min of ingestion, sudden headache, nausea, abdominal discomfort, and light-headedness were observed ... effects disappeared within 5 min. ".."Industrially men exposed to low concentrations of the gas in air have been noted occasionally to suffer from irritation of the eyes and to see haloes about lights, but these effects have been minor compared to respiratory irritation. "".."CHLORINE DIOXIDE (1, 10, 100 PPM) GIVEN DAILY IN DRINKING WATER DECR BLOOD GLUTATHIONE, DECR OSMOTIC FRAGILITY, & CHANGED MORPHOLOGY OF ERYTHROCYTES IN BOTH CHICKENS & RATS AFTER TWO MO."..."CHLORINE DIOXIDE IS RAPID DISINFECTING AGENT & HAS SAME SURVIVAL RATIO AS CHLORINE BUT WITH MUCH LOWER RESIDUAL CONCN WHEN CHLORINE EXISTS AS CHLORAMINES. CHLORINE DIOXIDE IS MORE EFFECTIVE VIRUCIDE THAN CHLORINE IN SECONDARY EFFLUENT. "