Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 231-821-4 | CAS number: 7757-83-7
Ecotoxicological Summary
Administrative data
Hazard for aquatic organisms
Freshwater
- Hazard assessment conclusion:
- no hazard identified
Marine water
- Hazard assessment conclusion:
- no hazard identified
STP
- Hazard assessment conclusion:
- no hazard identified
Sediment (freshwater)
- Hazard assessment conclusion:
- no hazard identified
Sediment (marine water)
- Hazard assessment conclusion:
- no hazard identified
Hazard for air
Air
- Hazard assessment conclusion:
- no hazard identified
Hazard for terrestrial organisms
Soil
- Hazard assessment conclusion:
- no hazard identified
Hazard for predators
Secondary poisoning
- Hazard assessment conclusion:
- no potential for bioaccumulation
Additional information
Conclusion on classification
Studies on the aquatic toxicity of sodium sulfite are available for fish (Leuciscus idus and Danio rerio, for acute and chronic toxicity respectively). In addition, read-across to sulfite/disulfite and thiosulfate substances is applied.Upon contact with water, salts of sulfur oxyacids including sodium sulfite dissociate into sulfur oxyacid anions and the respective counterions. Only the properties of the sulfite anion are considered a relevant determinant of environmental toxicity since sodium cations are essential for animals and have a very low potential for toxicity to freshwater and saltwater organisms.
Acute and long-term toxicity data for sulfite/disulfite and thiosulfate substances are available for three trophic levels. The lowest LC/EC50 for fish, crustacean or algae is a 72-h ErC50 of 36.8 mg SO32-/L (based on sulfite), observed for the effect of disodium sulfite on the growth rate of Desmodesmus subspicatus in a guideline test (BASF, 1989). However, a pH decrease was observed at the level of the derived EC50 so that it cannot be excluded that observed toxicity was caused by it. The lowest LC/EC50 of acute toxicity tests with controlled pH and oxygen concentrations is the 48-h EC50 of 124.2 mg SO32-/L derived for the immobilization of Daphnia magna by ammonium thiosulfate in a guideline test (Springborn Binomics Inc, 1986), and this EC50 is selected as acute ecotoxicity reference value for classification.
The lowest chronic NOEC/EC10 for freshwater fish, invertebrates or algae from a standard test is the 72-h EC10 of 28 mg SO32-/L for the effect of disodium sulfite on the growth rate of Desmodesmus subspicatus (BASF, 1989), and this value was selected as chronic reference value for classification.
Since sodium sulfite is an inorganic substance, biodegradation is not relevant.
For the classification of sodium sulfite, the acute and long-term ecotoxicity reference values of 124.2 and 28 mg sulfite/L are converted to mg Na2SO3/L, resulting in 195.5 mg/L and 44.1 mg/L sodium sulfite, respectively. Based on the acute ecotoxicity reference value and classification criteria of Regulation (EC) No 1272/2008, Table 4.1.0 (a), sodium sulfite does not meet classification criteria of Acute (short-term) aquatic hazard (acute reference value > 1 mg/L). Taking into account the chronic ecotoxicity reference value, sodium sulfite does also not meet classification criteria of Chronic (long-term) aquatic hazard (chronic reference value > 1 mg/L) in accordance with Table 4.1.0 (b(i)).
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
