Reference Documents on Relevant Chemicals

Chlorine Dioxide (CLO2) - Chlorine Dioxide (CLO2) Chlorine dioxide is a chemical compound with the formula ClO2. This reddish-yellow gas crystallizes as orange crystals at −59 C. As one of ...

Technical details about Chlorine Dioxide, learn more about the structure, uses, toxicity, action, side effects and more

{Methods of measurement, etc}

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1997

(2000)

FAQ chlorine dioxide

"Chlorine dioxide is generally effective for the deactivation of pathogenic microorganisms. It is less effective for the deactivation of rotaviruses and E. coli bacteria." [Note: Some ClO2 products are very economical] "The costs of chlorine dioxide depend upon the price of the chemicals that are used to produce chlorine dioxide."

{Workplace exposure limits, monitoring method, on-site screening techniques, etc}

****!!!!****!!!!** "**Sodium chlorite solutions should never be allowed to dry on fabrics** because this would result in a flammable combination" "The presence of chloride ions is essential for the formation of chlorine dioxide" "No significant amount of chlorine dioxide is formed in acidified chlorate solutions with various reducing agents when chloride has previously been removed from the reaction system by adding silver sulfate." "If chlorine dioxide generators are allowed to stand overnight, minor ClO2 formation consumes all of the chloride present in the reaction mass. When the supply of fresh raw materials is started the next morning, a specific chloride level must build up before chlorine dioxide can be produced at the desired rate" "Independent on the choice of reducing agent, the primary reaction for chlorine dioxide production is the reaction between chloric acid and hydrochloric acid to form chlorine dioxide and chlorine. Traces of Mn2+ and Ag+ ions catalyze the reaction" "In industrial chlorine dioxide production, sulfur dioxide, hydrochloric acid, or methanol are used as reducing agents. Other reducing agents are not economical" " solid sodium chlorite forms explosive mixtures with such oxidizable materials as sulfur, powdered coal, metal powders, or organic compounds." "t. At low pH (approximately 2), chlorite solutions contain chlorous acid that decomposes to form chlorine dioxide and chlorate... At pH 3 – 4, decomposition slows down. Alkaline solutions are stable, and dilute solutions can even be boiled without decomposition. Concentrated alkaline solutions of sodium chlorite slowly decompose when heated... The reaction of sodium chlorite with hypochlorite depends on pH [137]. At low pH, the reaction produces chlorine dioxide, whereas at high pH, chlorate is formed. The reaction with chlorine produces chlorine dioxide and sodium chloride" "Crystalline sodium chlorite is slightly hygroscopic without caking; it is stabilized with alkali for long-term storage" "The absorption of chlorine dioxide in caustic soda solution and the simultaneous reduction of chlorate to chlorite are achieved by a suitable reducing agent, such as hydrogen peroxide... The product is a 33 wt % solution of sodium chlorite, which is then converted to a dry solid containing ca. 80 wt % of sodium chlorite, the rest being stabilizers" "Sodium chlorite is a very efficient bleaching agent. Its oxidation potential allows a controlled bleaching that is not attainable with other bleaching agents"

*****!!!!****!!!** {Includes long list of research studies; regulations searches; patents; products from a broad range of manufacturers, and ingredients; etc}

OEHHA recommends an action level of 200 ug/L (ppb) chlorate in drinking water. " A concentration-dependent lag phase was seen before methemoglobin was formed, presumably reflecting time required for chlorate to enter or hemolyze RBCs. Other effects on RBCs included increased permeability to cations, increased resistance to hypotonic hemolysis, and prolonged filtration time through polycarbonate membranes. This suggests an increased RBC membrane rigidity due to membrane protein polymerization, as demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Simultaneously, erythrocyte enzymes were inactivated, primarily glucose-6-phosphate dehydrogenase."

1958. Vol. 19, No. 3, pp. 261-262.

2016

"At concentrations above 10% in air, chlorine dioxide may be explosive, and at 4% in air, it can be detonated by sparks" "The reduction of sodium chlorate is the more efficient process and is generally used when large volumes and high concentrations of chlorine dioxide are needed"

****!!!!*** {Excellent summaries of studies of effects on health, legal limits, etc}

****!!!!*** {Excellent summary of toxicity studies regarding health, and more}

{Includes industry exposure limits for air}

Learn about the process for periodically evaluating registered pesticides to ensure they meet current science standards for risk assessment, as required by the Federal Insecticide Fungicide and Rodenticide Act.

***!!!!*** 2017 Jan "Since in aqueous solutions, sodium hypochlorite (NaOCl) and chlorine share the same anion (ClO-) and, thus, release the very same active substance (i.e. active chlorine, thought to consist of hypochlorite, hypochlorous acid and chlorine in equilibrium), read-across is possible for all the toxicological end-points." "In the acute inhalation toxicity study (Anonymous, 1970), inactivity and lacrimation were evident at the dose of 10.5 mg avCl/L (1 h exposure). No deaths occurred (LC0 >10.5 mg avCl/L). Thus, the LC50 was determined to be greater than 10.5 mg avCl/L." "...by a factor of 4 for dusts and mists according to Annex I, notes to Table 1.1, paragraph c). However, in the case of sodium hypochlorite which only exerts local effects at the ****side [site?] of first contact, it is expected that local irritative effects are rather concentration than time dependent. Hence, findings for 4-h exposure durations are expected to be similar to those observed after 1-h exposures. " "ystemic toxicity after inhalation exposure towards sodium hypochlorite would therefore occur only secondary to locally irritating effects mainly caused by the local oxidation and basic nature of hypochlorite and its solutions. The remaining sodium and chloride ions are physiologically essential elements and are required in the intermediary metabolism and can therefore not be regarded as typical xenobiotics when entering the body."

"Acute oral LD50 = 1.1 g/kg BW (LD50 as available Cl2) = 1100 mg/kg BW NaClO as av. Cl2" "Dermal LD50 > 20 g/kg bw...2 of 8 animals died on day 1 and 2 after application in the high dose group (20 g/kg bw)." "The LC0 value by inhalation in rat was found to be greater than 10.5 mg/l for 1 hour exposure... inhalation exposure of sodium hypochlorite is only possible if aerosols are formed"

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Acute Oral LD50 5,800 mg/kg (5% w/v). Acute Dermal LD50 >3,000 mg/kg.