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Pyrosulfurous acid, disodium salt

RTECS #
UX8225000
CAS #
7681-57-4; 7757-74-6; 15771-29-6
See: NMAM or OSHA Methods
Updated
September 2018
Molecular Weight
190.10
Molecular Formula
O5S2·2Na
Synonyms
Disodium disulfite
Disodium metabisulfite
Disodium pyrosulfite
Disulfurous acid, disodium salt
Sodium disulfite
Sodium metabisulfite
Sodium metabisulfite (ACGIH)
Sodium metabisulphite
Sodium pyrosulfite

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
eye /rabbit 100 mg/24H mildNTIS** OTS0556759
skin /rabbit 500 mgNTIS** OTS0557608
skin /woman 0.02%CODEDG 60,115,2009

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysisovary/hamster180 µg/LENMUDM 7,1,1985
DNA Damageoral/mouse1 gm/kgMUREAV 720,58,2011
micronucleus testoral/mouse2 gm/kgMUREAV 720,58,2011
mutation in microorganisms/Salmonella typhimurium100 mmol/L (+enzymatic activation step)MUREAV 179,159,1987
sister chromatid exchangeovary/hamster200 µg/LENMUDM 7,1,1985

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
oral/rat 20 gm/kg (multigenerations)Reproductive: Effects on newborn: StillbirthFCTXAV 10,291,1972
oral/rat 40 gm/kg (multigenerations)Reproductive: Effects on newborn: Weaning or lactation index (e.g., # alive at weaning per # alive at day 4)FCTXAV 10,291,1972

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/mtbInhibitor Concentration Low: >1000 µmol/L/4DIn Vitro Toxicity Studies: Cell growth: Colony formationFCTOD7 109,376,2017
In Vitro/mtbInhibitor Concentration Low: 1000 µmol/L/4DIn Vitro Toxicity Studies: Cell morphology: overgrowth of cell appendixes etc.

In Vitro Toxicity Studies: Cell differentiation
FCTOD7 109,376,2017
In Vitro/pzxInhibitor Concentration (50 percent kill): 829.66 µmol/LVascular: Relaxation (isolated tissue)FCTOD7 50,3114,2012
In Vitro/pzxInhibitor Concentration Low: 400 µmol/LVascular: Relaxation (isolated tissue)FCTOD7 50,3114,2012
intravenous/rabbit lowest published lethal dose: 192 mg/kgTXAPA9 24,266,1973
intravenous/rat lethal dose (50 percent kill): 115 mg/kg85INA8 6,1418,1991
oral/rat lethal dose (50 percent kill): 1131 mg/kgBehavioral: Food intake (animal)

Behavioral: Muscle weakness

Skin and Appendages: Other: Hair
NTIS** OTS0556695
parenteral/mouse lethal dose (50 percent kill): 910 mg/kgRPTOAN 31,120,1968
skin/guinea pig lethal dose (50 percent kill): >1 gm/kgSkin: After systemic exposure: Dermatitis, other

Skin and Appendages: Other: Hair
NTIS** OTS0556695
skin/rat lethal dose (50 percent kill): >2 gm/kgNTIS** OTS0557608

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
oral/pig lowest published toxic dose: 562 gm/kg/48W- continuousLiver: Changes in liver weight

Kidney, Ureter, and Bladder: Changes in bladder weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
FCTXAV 10,463,1972
oral/rat lowest published toxic dose: 1050 mg/kg/6W- continuousBrain and Coverings: Other degenerative changes

Behavioral: Alteration of classical conditioning

Biochemical: Metabolism (intermediary): Lipids including transport
NETEEC 27,47,2005
oral/rat lowest published toxic dose: 1050 mg/kg/6W- continuousBrain and Coverings: Recordings from specific areas of CNS

Eye: Retinal changes pigmentary deposition, retinitis, other)

Biochemical: Metabolism (intermediary): Lipids including transport
NETOX* 27,93,2006
oral/rat lowest published toxic dose: 3500 mg/kg/35D- intermittentBrain and Coverings: Recordings from specific areas of CNS

Brain and Coverings: Other degenerative changes

Eye: Retinal changes pigmentary deposition, retinitis, other)
NETEEC 33,244,2011
oral/rat lowest published toxic dose: 3500 mg/kg/5W- intermittentBrain and Coverings: Changes in surface EEG

Brain and Coverings: Other degenerative changes

Biochemical: Metabolism (intermediary): Lipids including transport
FCTOD7 52,129,2013
oral/rat lowest published toxic dose: 3500 mg/kg/5W- intermittentLiver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Xanthine oxidases

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other enzymes
FCTOD7 76,27,2015
oral/rat lowest published toxic dose: 10346 mg/kg/7D- continuousBehavioral: Food intake (animal)

Blood: Changes in erythrocyte (RBC) count

Blood: Changes in leukocyte (WBC) count
RTOPDW 80,277,2016
oral/rat lowest published toxic dose: 10346 mg/kg/7D- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainRTOPDW 80,277,2016
oral/rat lowest published toxic dose: 75 mg/kg/15D- continuousKidney, Ureter, and Bladder: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Phosphatases

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Dehydrogenases
TXCYAC 81,173,1993

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 5 mg/m3DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 54,131,1992
International Agency for Research on Cancer (IARC)Cancer Review:Animal Inadequate EvidenceIMEMDT 54,131,1992
International Agency for Research on Cancer (IARC)Cancer Review:Group 3IMEMDT 54,131,1992
TOXICOLOGY REVIEWIJTOFN 22,63,2003
TOXICOLOGY REVIEWHUTOX* -,259,1996

Standards and Regulations

OrganizationStandardReference
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAtime-weighted average 5 mg/m3, JUL2008
Occupational Exposure Limit-BELGIUMtime-weighted average 5 mg/m3, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 5 mg/m3, MAY2011
Occupational Exposure Limit-FRANCEVME 5 mg/m3, FEB2006
Occupational Exposure Limit-ICELANDtime-weighted average 5 mg/m3, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 5 mg/m3, 2006
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 5 mg/m3, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 5 mg/m3, JAN1999
Occupational Exposure Limit-PERUtime-weighted average 5 mg/m3, JUL2005
Occupational Exposure Limit-SWITZERLANDMAK-week 5 mg/m3, inhal, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 5 mg/m3, 2003
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 5 mg/m3, OCT2007

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO SODIUM METABISULFITE-air10H time-weighted average 5 mg/m3NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code X4004; Number of Industries 73; Total Number of Facilities 8367; Number of Occupations 68; Total Number of Employees Exposed 88236; Total Number of Female Employees Exposed 28696

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Negative: TRP reversion
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
Page last reviewed: November 16, 2018