|Substance Group: Sodium percarbonate |
Sodium percarbonate is mainly used as a bleaching chemical in laundry detergents, laundry additives and machine dishwashing products. The pure product (100 %) is also available for consumers as a laundry additive. Sodium percarbonate may also be used in products for drain cleaning, multipurpose cleaning or for denture cleansing. The amount of sodium percarbonate, which is used in household cleaning products in Europe, was estimated to be 100,000 – 150,000 tonnes in 2001 but the amount is expected to increase the coming years.
Sodium percarbonate rapidly dissolves in water and dissociates into sodium, carbonate and hydrogen peroxide. Acute ecotoxicity tests with fish and water fleas revealed LC50 values of 71 and 4.9 mg/l. The available data show that the observed aquatic toxicity of sodium percarbonate can be explained by the formation of hydrogen peroxide. Because sodium percarbonate dissociates into sodium, carbonate and hydrogen peroxide, the environmental risk assessment is based on the risk assessment of the individual components.
After use of the household cleaning product, the spent washing liquor (containing the sodium percarbonate) will be disposed via the drain. Neither hydrogen peroxide nor carbonate will be discharged to aquatic ecosystems. Hydrogen peroxide will degraded in the biological waste water treatment plant, while carbonate will be neutralised by the biological waste water treatment plant to bicarbonate. Sodium has a low toxicity and the emitted amount of sodium is relatively low compared to background concentrations and therefore the emitted amount of sodium will not have an effect on the aquatic organisms of the receiving water.
Based on the available data, the use of sodium percarbonate in household cleaning products has no adverse effect on the aquatic ecosystem.
Sodium percarbonate has a low acute toxicity via the oral and dermal route (LD50 > 1000 mg/kg bodyweight). The existing animal data on acute toxicity show that sodium percarbonate has a local effect. In animal tests a slight irritating effect on the skin was reported for solid sodium percarbonate and it was highly irritating to the rabbit eye (not rinsed). Sodium percarbonate did not have sensitising properties in a test with guinea pigs.
When consumers are exposed to sodium percarbonate, neither hydrogen peroxide nor sodium carbonate will be systemically available due to their effective detoxification (degradation or neutralisation) in the body. Consequently it is to be expected that the concentration of hydrogen peroxide and sodium in the blood and the pH of the blood will not be increased. Therefore, neither sodium percarbonate itself nor hydrogen peroxide or carbonate will reach the organs or the foetus and there is no risk for systemic, developmental or reproductive toxicity. With regard to genotoxicity and carcinogenicity the properties of sodium percarbonate also resemble those of hydrogen peroxide and it can be concluded that there is no concern for humans with regard to a possible genotoxicity or carcinogenicity of sodium percarbonate. The only critical endpoint for sodium percarbonate seems to be local irritation.
Consumers can be exposed to sodium percarbonate due to skin contact with solutions which contain sodium percarbonate, which can be laundry hand washing. However, the estimated concentrations of sodium percarbonate in these solutions are too low to cause skin irritation.
Accidental exposure of the eyes to dry products which contain sodium percarbonate or to solutions of household cleaning products which contain sodium percarbonate could result in eye irritation. Only if the sodium percarbonate concentration in the product or the solution is very high (> 25%) irreversible damage to the eye could occur if the product is not immediately washed out, which would normally be the case.
Acute cases of oral poisoning or effects on human eyes, due to accidental or intentional overexposure to sodium percarbonate, have not been found in the literature.
Based on the available data, the use of sodium percarbonate in household cleaning products has no adverse effect on consumers.