Metam-sodium

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from authoritative database.

Data source

Reference

Reference 1

Reference Type:

other: authoritative database

Title:

Acute Inhalation toxicity of Metam-sodium (CAS no: 137-42-8) in rat.

Author:

IFA GESTIS

Year:

2017

Bibliographic source:

IFA GESTIS, GESTIS SUBSTANCE Database, 2017

Reference 2

Reference Type:

other: authoritative database

Title:

Acute Inhalation toxicity of Metam-sodium (CAS no: 137-42-8) in rat

Author:

U.S. National Library of Medicine

Year:

2008

Bibliographic source:

HSDB (Hazardous Substances Data Bank), US national Library of Medicine, 2008

Reference 3

Reference Type:

secondary source

Title:

IUCLID Dataset of Metam-sodium (CAS no: 137-42-8).

Author:

EUROPEAN COMMISSION – European Chemicals Bureau

Year:

2000

Bibliographic source:

IUCLID Dataset of Metam-sodium (CAS no: 137-42-8), EUROPEAN COMMISSION – European Chemicals Bureau, 18–FEB–2000.

Reference 4

Reference Type:

secondary source

Title:

Draft Assessment Report (Metam-sodium), ANNEX B.6 Toxicology and metabolism

Author:

European Food Safety Authority (EFSA)

Year:

2007

Bibliographic source:

Draft Assessment Report (Metam-sodium) - Volume 3, Annex B, part 2, B.6, October 2007.

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Principles of method if other than guideline:

Acute inhalation toxicity of Metam-sodium (CAS no: 137-42-8) in rat.

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Metam-sodium

EC Number:

205-293-0

EC Name:

Metam-sodium

Cas Number:

137-42-8

Molecular formula:

C2H5NS2.Na

IUPAC Name:

sodium (methylcarbamothioyl)sulfanide

Details on test material:

- IUPAC Name: Metam-sodium
- InChI: 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Smiles: C(=S)(NC)[S-].[Na+]
- Molecular formula :C2H4NNaS2
- Molecular weight:129.1826 g/mol
- Substance type:Organic

Specific details on test material used for the study:

- IUPAC Name: Metam-sodium
- InChI: 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Smiles: C(=S)(NC)[S-].[Na+]
- Molecular formula :C2H4NNaS2
- Molecular weight:129.1826 g/mol
- Substance type:Organic

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

not specified

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: aqueous formulation containing 42.2% methylcarbamodithionic acid monosodium salt

Mass median aerodynamic diameter (MMAD):

2.6 µm

Remark on MMAD/GSD:

not specified

Details on inhalation exposure:

not specified

Analytical verification of test atmosphere concentrations:

not specified

Duration of exposure:

4 h

Remarks on duration:

not specified

Concentrations:

6.8 mg/L (6800 mg/m3)

No. of animals per sex per dose:

5 rats/sex/dose

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 7 days
- Frequency of observations and weighing: Animals were observed for mortality, clinical signs and body weight change.

Statistics:

not specified

Results and discussion

Preliminary study:

not specified

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 6.8 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: No mortality was observed

Mortality:

No mortality was observed at 6.8 mg/L air (6800 mg/m3)

Clinical signs:

other: Clinical signs during exposure animals attempt to escape. Reddish discharge from the nose and discharge from eyes were noted. After inhalation, hair in the genital area was covered with reddish crusts as well as part of the nose covered with reddish crust

Body weight:

Body weight gain of male rats was retarded in the first week of observation period but recovered in the second week. Body weight gain of females remained slightly retarded over the total observation period.

Gross pathology:

No organ abnormalities were detected.

Other findings:

not specified

Applicant's summary and conclusion

Interpretation of results:

other: Not classified

Conclusions:

The acute inhalation LC50 value was considered to be > 6.8 mg/L (>6800 mg/m3), when 10 Wistar rats were treated with Metam-sodium (CAS no: 137-42-8) via inhalation route by aerosol for 4 hours exposure.

Executive summary:

Acute inhalation toxicity study of Metam-sodium (CAS no: 137-42-8)was conducted according to OECD Guide–line 403 "Acute Inhalation Toxicity"in 10 Wistar rats at the concentration of 6.8 mg/L (6800 mg/m3). The rats were exposed to metam sodium (batch n° ZH 130 585, 42.2% aqueous solution) by head-nose to an aerosol air mixture for 4 hours (MMAD 50% = 2.6 μm; 90.1% was respirable). Animals were observed for mortality, clinical signs and body weight change for 7 days. No mortality was observed at 6.8 mg/L air (6800 mg/m3). Clinical signs during exposure animals attempt to escape. Reddish discharge from the nose and discharge from eyes were noted. After inhalation, hair in the genital area was covered with reddish crusts as well as part of the nose covered with reddish crusts. Stepping gait was slightly high and respiration was slightly sound. The poisoning symptoms confirmed the pronounced irritation described above (fully reversible within 7 days). Body weight gain of male rats was retarded in the first week of observation period but recovered in the second week. Body weight gain of females remained slightly retarded over the total observation period. No organ abnormalities were detected. Therefore, LC50 value was considered to be > 6.8 mg/L (>6800 mg/m3), when 10 Wistar rats were treated with Metam-sodium (CAS no: 137-42-8) via inhalation route by aerosol for 4 hours exposure.