Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.

Diss Factsheets

Administrative data

Description of key information

Repeated dose oral toxicity:

NOEL was considered to be 0.3 mg/kg bw /day for Metam Sodium in male and female rats for sub chronic study by oral gavage.

Repeated inhalation study:

NOAEL was considered to be 0.51 mg/l for Metam Sodium in Sprague–Dawley male and female rats for subacute study by inhalation route.

Repeated dermal study;

NOAEL was considered to be 31.25 mg/kg bw/day for Metam Sodium in White Russians male and female rabbits for 21 days by dermal application.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records
Reference
Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
secondary literature
Justification for type of information:
Data is from secondary source
Qualifier:
according to guideline
Guideline:
other: As mention below
Principles of method if other than guideline:
To evaluate the toxicity of Metam Sodium in male and female rats for subchronic study.
GLP compliance:
not specified
Limit test:
no
Specific details on test material used for the study:
- Name of test material : Metam-sodium
- Molecular formula : C2H4NNaS2
- Molecular weight : 129.1826 g/mol
- Smiles notation : C(=S)(NC)[S-].[Na+]
- InChl : 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Substance type: Organic
- Physical state: Solid
Species:
rat
Strain:
not specified
Sex:
male/female
Details on test animals or test system and environmental conditions:
Not specified
Route of administration:
oral: gavage
Details on route of administration:
Not specified
Vehicle:
not specified
Details on oral exposure:
Not specified
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
5 weeks
Frequency of treatment:
3 times per week
Remarks:
0and 0.3 mg/kg bw /day
No. of animals per sex per dose:
Total 40 animals
0 mg/kg bw /day – 10 male and 10 females
0.3 mg/kg bw /day- – 10 male and 10 females
Control animals:
yes, concurrent vehicle
Details on study design:
Not specified
Positive control:
Not specified
Observations and examinations performed and frequency:
Observations and examinations performed & frequency
CAGE SIDE OBSERVATIONS: Not specified

DETAILED CLINICAL OBSERVATIONS: Not specified

BODY WEIGHT: Yes

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Not specified
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes / No / No data

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Yes / No / No data

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Not specified

OPHTHALMOSCOPIC EXAMINATION: Not specified

HAEMATOLOGY: Yes
- Time schedule for collection of blood:
1st examination was conducted after 1 or 3 weeks of treatment.
2nd examination was conducted after 5 weeks of treatment.
3rd examination was conducted 2 weeks after the end of treatment

- How many animals:
1st examination was conducted on 6 animals.
2nd examination was conducted on 10 animals.
3rd examination was conducted on 4 animals.

- Parameters checked in table [No.?] were examined. Hemoglobin concentration and leukocyte counts were determined from blood samples.


CLINICAL CHEMISTRY: Not specified

URINALYSIS: Not specified

NEUROBEHAVIOURAL EXAMINATION: Not specified


OTHER: Organ weight; Liver and kidneys were weighed.
Sacrifice and pathology:
GROSS PATHOLOGY: Yes, After treatment for 1 or 3 weeks each 3 animals per sex were sacrificed and animals were examined gross–pathologically. After 5 weeks of treatment 10 animals per sex were sacrificed. The remaining 4 male and female animals were sacrificed 2 weeks after the end of treatment and examined gross–pathologically.
.

HISTOPATHOLOGY: Yes , Various organs from each male and
Female animals were examined.
Other examinations:
Not specified
Statistics:
Not specified
Clinical signs:
not specified
Mortality:
mortality observed, treatment-related
Description (incidence):
Two male animals died during the study.
Body weight and weight changes:
not specified
Food consumption and compound intake (if feeding study):
not specified
Food efficiency:
not specified
Water consumption and compound intake (if drinking water study):
not specified
Ophthalmological findings:
not specified
Haematological findings:
no effects observed
Description (incidence and severity):
Leucocyte count and methemoglobin levels were not alltered at any time point in treated group compare to control.
Clinical biochemistry findings:
not specified
Urinalysis findings:
not specified
Behaviour (functional findings):
not specified
Immunological findings:
not specified
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
At the end of the treatment, relative liver and kidney weights were increased. These effects were reversible within the Post exposure period.
Gross pathological findings:
no effects observed
Description (incidence and severity):
No pathological findings were observed in the animals sacrificed after 1 or 3 weeks of treatment in treated group compare to control.
Neuropathological findings:
not specified
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
In the forestomach of animals which were sacrificed at the end of the treatment period, scar formation and hyperlasia of the mucosa was observed. The other organs were without any findings in treated group compare to control.
Histopathological findings: neoplastic:
not specified
Other effects:
not specified
Description (incidence and severity):
not specified
Key result
Dose descriptor:
NOAEL
Effect level:
0.3 other: mg/kg bw /day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No significant effect were observed at this dose.
Remarks on result:
other: No toxic effect observed.
Critical effects observed:
not specified
System:
other: not specified
Organ:
not specified
Treatment related:
not specified
Dose response relationship:
not specified
Relevant for humans:
not specified
Conclusions:
NOEL was considered to be 0.3 mg/kg bw /day for Metam Sodium in male and female rats for sub chronic study by oral gavage.
Executive summary:

Repeated dose oral toxicity study ofMetam Sodiumwas assessed for its possible toxic potential. For this purpose a subchronic study was conducted in male and female rats by using test substance at the concentration of 0and0.3mg/kg bw . The test substance was administrated 3 times per week for 5 weeks by oral gavage. Animals were observed for mortality, clinical sign, hematology, organ weight, gross and histopathology. Two male animals died during the study. At the end of the treatment, relative liver and kidney weights were increased. These effects were reversible within the post exposure period. Leucocyte count and methemoglobin levels were not alltered at any timepoint. No pathological findings were observed in the animals sacrificed after 1 or 3 weeks of treatment. In the forestomach of animals which were sacrificed at the end of the treatment period, scar formation and hyperlasia of the mucosa was observed. The other organs were without any findings. As no significant effect were observed at0.3mg/kg. Therefore NOEL was considered to be 0.3 mg/kg bw /day forMetam Sodium in male and female rats for sub chronic study by oral gavage.


Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
0.3 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
K4 Data from European Commission

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records
Reference
Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
secondary literature
Justification for type of information:
Data is from secondary source.
Qualifier:
according to guideline
Guideline:
other: As mention below
Principles of method if other than guideline:
To evaluate the toxicity of Metam Sodium in Sprague–Dawley male and female rats for subacute study.
GLP compliance:
not specified
Limit test:
no
Specific details on test material used for the study:
- Name of test material : Metam-sodium
- Molecular formula : C2H4NNaS2
- Molecular weight : 129.1826 g/mol
- Smiles notation : C(=S)(NC)[S-].[Na+]
- InChl : 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Substance type: Organic
- Physical state: Solid
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Route of administration:
inhalation: aerosol
Type of inhalation exposure:
not specified
Vehicle:
not specified
Details on inhalation exposure:
Not specified
Analytical verification of doses or concentrations:
not specified
Details on analytical verification of doses or concentrations:
Not specified
Duration of treatment / exposure:
3 weeks
Frequency of treatment:
daily – 4 hours per day
Remarks:
0.51, 1.54 and 4.53 mg/l
No. of animals per sex per dose:
0.51, 1.54 and 4.53 mg/l
Control animals:
yes, concurrent vehicle
Details on study design:
Not specified
Observations and examinations performed and frequency:
Observations and examinations performed & frequency
CAGE SIDE OBSERVATIONS: Not specified.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Daily

BODY WEIGHT: Not specified .

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Not specified - Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Not specified
FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Yes / No / No data

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Not specified

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: At the end of
the study ophthalmology l was performed.



HAEMATOLOGY: Yes
- Time schedule for collection of blood: At the end of
the study hematology was performed.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: At the end of the study clinical chemistry was performed.



URINALYSIS: Yes
- Time schedule for collection of urine: At the end of the study urinalysis was performed.



NEUROBEHAVIOURAL EXAMINATION: Not specified
Sacrifice and pathology:
Sacrifice and pathology
GROSS PATHOLOGY: Yes, At the end of the study gross–pathological examinations were performed.

HISTOPATHOLOGY: Yes , At the end of the study
histological examinations were performed.
Statistics:
Not specified
Clinical signs:
no effects observed
Description (incidence and severity):
During 21 days of treatment with the test substance no influence on the animals was seen at the low dose level (0.51 mg/l)
Mortality:
mortality observed, treatment-related
Description (incidence):
The treated animals being exposed to the highest dose (4.53 mg/l) 1 female and 10 males died during the study. No mortality observed in control.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
At the medium dosage (1.54 g/l) body weight gain of both sexes in treated group was markedly inhibited compare to control .
At the high dosage (4.53 mg/l) body weight gain was markedly diminished) in treated group compare to control.
Food consumption and compound intake (if feeding study):
not specified
Food efficiency:
not specified
Water consumption and compound intake (if drinking water study):
not specified
Ophthalmological findings:
not specified
Haematological findings:
effects observed, treatment-related
Description (incidence and severity):
At the medium dosage (1.54 g/l) hemoglobin content in male and female and the number of leukocytes were
increased (only females) in treated group was markedly inhibited compare to control.

At the high dosage (4.53 mg/l) hemoglobin content,
erythrocyte–and platelet count in blood were increased.
Leucocytes and reticulocytes were slightly reduced in treated group compare to control.
Clinical biochemistry findings:
not specified
Urinalysis findings:
not specified
Behaviour (functional findings):
not specified
Immunological findings:
not specified
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Description (incidence and severity):
At the medium dosage (1.54 g/l) Organ weights (except adrenals of the males) were reduced) in treated group was markedly inhibited compare to control.

At the high dosage (4.53 mg/l) the weighed internal organs showed markedly reduced absolute values, whereas relative lung weight was increased
Gross pathological findings:
not specified
Neuropathological findings:
not specified
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
At the medium dosage (1.54 g/l) histopathological examinations showed pulmonary lesions (alveolar emphysema) in treated group was markedly inhibited compare to control.

At the high dosage (4.53 mg/l) microscopic examination showed multiple pulmonary lesions, thymic atrophy, hyperplasia and depletion, inhibited spermiogenesis, atrophic prostate, tracheitis, changes in the urinary bladder and inflammatory, partly purulent, degenerations in the nasal cavity, maxillary sinus and meatus which might be due to the treatment.
Histopathological findings: neoplastic:
not specified
Other effects:
not specified
Key result
Dose descriptor:
NOAEL
Effect level:
0.51 other: mg/l
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No significant effct were observed at this dose
Remarks on result:
other: No toxic effct were observed
Critical effects observed:
not specified
System:
other: not specified
Organ:
not specified
Treatment related:
not specified
Dose response relationship:
not specified
Relevant for humans:
not specified
Conclusions:
NOAEL was considered to be 0.51 mg/l for Metam Sodium in Sprague–Dawley male and female rats for subacute study by inhalation route.
Executive summary:

Repeated dose inhalation study ofMetam Sodium was assessed for its possible toxic nature.For this purpose subacute study was conducted on Sprague–Dawley male and female rats by using test substance at the concentration of0.51, 1.54 and 4.53 mg/l. The test substance was exposed daily – 4 hours per day for 3 weeks. The animals were observed for mortality, clinical chemistry, body weight, hematology, organ weight histopathology and gross pathology. Significant effect were observed at the medium dosage (1.54 g/l) and high dosage (4.53 mg/l) . During 21 days of treatment with the test substance no influence on the animals was seen at the low dose level (0.51 mg/l). Therefore NOAEL was considered to be 0.51 mg/l forMetam Sodium in Sprague–Dawley male and female rats for subacute study by inhalation route.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEC
0.51 mg/m³
Study duration:
subacute
Species:
rat
Quality of whole database:
K4 Data from European Commission

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records
Reference
Endpoint:
short-term repeated dose toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
secondary literature
Justification for type of information:
Data is from secondary source.
Qualifier:
according to guideline
Guideline:
other: As mention below
Principles of method if other than guideline:
To evaluate the toxicity for Metam Sodium in White Russians male and female rabbits for 21 days by dermal application.
GLP compliance:
not specified
Limit test:
no
Specific details on test material used for the study:
- Name of test material : Metam-sodium
- Molecular formula : C2H4NNaS2
- Molecular weight : 129.1826 g/mol
- Smiles notation : C(=S)(NC)[S-].[Na+]
- InChl : 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Substance type: Organic
- Physical state: Solid
Species:
rabbit
Strain:
other: White Russians
Sex:
male/female
Details on test animals or test system and environmental conditions:
Not specified.
Type of coverage:
not specified
Vehicle:
other: 0.8% hydroxypropylmethylcellulose
Details on exposure:
The test substance was applied to the shaved intact and abraded skin for an exposure time of 8 hours a day in 0.8% hydroxypropylmethylcellulose.
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
21 days
Frequency of treatment:
daily
Remarks:
0,31.25, 62.5 and 125 mg/kg bw /day
No. of animals per sex per dose:
5 animals/dose level/sex/skin/condition
Control animals:
yes, concurrent vehicle
Details on study design:
Not specified
Positive control:
Not specified
Observations and examinations performed and frequency:
Observations and examinations performed & frequency
CAGE SIDE OBSERVATIONS: Not specified

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Daily

DERMAL IRRITATION (if dermal study): Yes
- Time schedule for examinations: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Weekly

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Not specified

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Not specified

WATER CONSUMPTION: Not specified

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: At the end of the study.


HAEMATOLOGY: Yes
- Time schedule for collection of blood: performed in all
animals before the first application as well as after the
three test weeks

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: performed in all
animals before the first application as well as after the
three test weeks


URINALYSIS: Yes
- Time schedule for collection of urine: performed in all
animals before the first application as well as after the
three test weeks

NEUROBEHAVIOURAL EXAMINATION: Not specified
Sacrifice and pathology:
Sacrifice and pathology
GROSS PATHOLOGY: Not specified
HISTOPATHOLOGY: Yes, at the end of the study microscopic examination was performed.
Statistics:
Not specified
Clinical signs:
no effects observed
Description (incidence and severity):
The lowest dosage (31.25 mg/kg bw/d) was tolerated without any local effects in treated group compare to control.

Middle dose (62.5 mg/kg) caused locally slight to moderate erythema as well as slight edema. After discontinuation of dosing erythema disappeared rapidly,
edema had receded before in treated group.

At high dose 125 mg/kg caused more severe skin injury. Erythema were seen with formation of rhagades. Moderate edema were also observed. After 21 days of application these skin changes were found in all treated animals compare to control.
Dermal irritation:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Mortality:
no mortality observed
Description (incidence):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Body weight and weight changes:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Food consumption and compound intake (if feeding study):
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Food efficiency:
not specified
Water consumption and compound intake (if drinking water study):
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Ophthalmological findings:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Haematological findings:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Clinical biochemistry findings:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Urinalysis findings:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Behaviour (functional findings):
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Immunological findings:
not specified
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Gross pathological findings:
no effects observed
Description (incidence and severity):
No significant effect were observed at all doses 0,31.25, 62.5 and 125 mg/kg bw in treated group compare to control.
Neuropathological findings:
not specified
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
Histology showed slight epidermo–dermatitis in all animals. During the follow–up period, all local effects disappeared within 4–11 days. At 125 mg/kg moderate to marked epiderm–dermatitis was seen in all animals after the period of application but this was reversible within the follow–up period.
Histopathological findings: neoplastic:
not specified
Other effects:
not specified
Dose descriptor:
NOAEL
Effect level:
31.25 other: mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No significant effect were observed at this dose
Remarks on result:
other: No toxic effecty were observed
Critical effects observed:
not specified
System:
other: not specified
Organ:
not specified
Treatment related:
not specified
Dose response relationship:
not specified
Relevant for humans:
not specified
Conclusions:
NOAEL was considered to be 31.25 mg/kg bw/day for Metam Sodium in White Russians male and female rabbits for 21 days by dermal application.
Executive summary:

Repeated dose dermal toxicity study was assessed for possible toxic potential. For this purpose Subacute assay was performed onWhite Russians male and female rabbits by using a concentration of 0, 31.25, 62.5 and 125 mg/kg bw/day. The test substance was applied to the shaved intact and abraded skin for an exposure time of 8 hours a day in 0.8% hydroxypropylmethylcellulose for 21 days. Skin reactions as well as behaviour and external appearance were observed daily. Body weights were determined once a week. Urinalysis, haematology and clinical chemical investigations were performed in all animals before the first application as well as after the three test weeks. Ophthalmological, gross–pathological and histological examinations were carried out in all animals at the end of the study. The lowest dosage (31.25 mg/kg bw/d) was tolerated without any local effects. 62.5 mg/kg caused locally slight to moderate erythema as well as slight edema.After discontinuation of dosing erythema disappeared rapidly,edema had receded before. 125 mg/kg caused more severe skin injury. Erythema were seen with formation of rhagades. Moderate edema were also observed. After 21 days of application these skin changes were found in all animals. Histology showed slight epidermo–dermatitis in all animals. During the follow–up period, all local effects disappeared within 4–11 days. At 125 mg/kg moderate to marked epiderm–dermatitis was seen in all animals after the period of application but this was reversible within the follow–up period. Therefore NOAEL was considered to be 31.25 mg/kg bw/day for Metam Sodium in White Russians male and female rabbits for 21 days by dermal application.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
31.25 mg/kg bw/day
Study duration:
subacute
Species:
rabbit
Quality of whole database:
K4 Data from European Commission

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Repeated dose oral toxicity:

Experimental study was reviewed to determine the toxic nature of Metam-sodium (137-42-8) upon repeated exposure by oral route. The studies are as mentioned below:

Sub-Chronic oral toxicity study was observed by European Commission (European Chemicals Bureau, 2000) to determine the oral toxic nature of Metam-sodium (137-42-8 ) upon repeated exposure for 5 weeks. Repeated dose oral toxicity study ofMetam Sodiumwas assessed for its possible toxic potential. For this purpose a subchronic study was conducted in male and female rats by using test substance at the concentration of 0and0.3mg/kg bw . The test substance was administrated 3 times per week for 5 weeks by oral gavage. Animals were observed for mortality, clinical sign, hematology, organ weight, gross and histopathology. Two male animals died during the study. At the end of the treatment, relative liver and kidney weights were increased. These effects were reversible within the post exposure period. Leucocyte count and methemoglobin levels were not alltered at any timepoint. No pathological findings were observed in the animals sacrificed after 1 or 3 weeks of treatment. In the forestomach of animals which were sacrificed at the end of the treatment period, scar formation and hyperlasia of the mucosa was observed. The other organs were without any findings. As no significant effect were observed at 0.3mg/kg. Therefore NOEL was considered to be 0.3 mg/kg bw /day for Metam Sodium in male and female rats for sub chronic study by oral gavage.

Based on the data available for the target chemical Metam-sodium (137-42-8) does not exhibit toxic nature upon repeated exposure by oral route of exposure and hence is not likely to classify as per the criteria mentioned in CLP regulation.

 

Repeated inhalation study:

Experimental study was reviewed to determine the toxic nature of Metam-sodium (137-42-8) upon repeated exposure by inhalation route. The studies are as mentioned below:

Subacute toxicity study was observed by European Commission (European Chemicals Bureau, 2000) to determine the oral toxic nature of Metam-sodium (137-42-8 ) upon repeated exposure for 3 weeks. Repeated dose inhalation study ofMetam Sodium was assessed for its possible toxic nature. For this purpose subacute study was conducted on Sprague–Dawley male and female rats by using test substance at the concentration of0.51, 1.54 and 4.53 mg/l. The test substance was exposed daily – 4 hours per day for 3 weeks. The animals were observed for mortality, clinical chemistry, body weight, hematology, organ weight histopathology and gross pathology. Significant effect were observed at the medium dosage (1.54 g/l) and high dosage (4.53 mg/l) . During 21 days of treatment with the test substance no influence on the animals was seen at the low dose level (0.51 mg/l). Therefore NOAEL was considered to be 0.51 mg/l for Metam Sodium in Sprague–Dawley male and female rats for subacute study by inhalation route.

Based on the data available for the target chemical Metam-sodium (137-42-8) does not exhibit toxic nature upon repeated exposure by inhalation of exposure and hence is not likely to classify as per the criteria mentioned in CLP regulation.

 

Repeated dermal study;

Experimental study was reviewed to determine the toxic nature of Metam-sodium (137-42-8) upon repeated exposure by dermal route. The studies are as mentioned below:

Subacute toxicity study was observed by European Commission (European Chemicals Bureau, 2000) to determine the toxic nature of Metam-sodium (137-42-8 ) upon repeated exposure by dermal route for 21 days. Repeated dose dermal toxicity study was assessed for possible toxic potential. For this purpose Subacute assay was performed onWhite Russians male and female rabbits by using a concentration of 0, 31.25, 62.5 and 125 mg/kg bw/day. The test substance was applied to the shaved intact and abraded skin for an exposure time of 8 hours a day in 0.8% hydroxypropylmethylcellulose for 21 days. Skin reactions as well as behaviour and external appearance were observed daily. Body weights were determined once a week. Urinalysis, haematology and clinical chemical investigations were performed in all animals before the first application as well as after the three test weeks. Ophthalmological, gross–pathological and histological examinations were carried out in all animals at the end of the study. The lowest dosage (31.25 mg/kg bw/d) was tolerated without any local effects. 62.5 mg/kg caused locally slight to moderate erythema as well as slight edema.After discontinuation of dosing erythema disappeared rapidly,edema had receded before. 125 mg/kg caused more severe skin injury. Erythemas were seen with formation of rhagades. Moderate edema were also observed. After 21 days of application these skin changes were found in all animals. Histology showed slight epidermo–dermatitis in all animals. During the follow–up period, all local effects disappeared within 4–11 days. At 125 mg/kg moderate to marked epiderm–dermatitis was seen in all animals after the period of application but this was reversible within the follow–up period. Therefore NOAEL was considered to be 31.25 mg/kg bw/day for Metam Sodium in White Russians male and female rabbits for 21 days by dermal application.

Based on the data available for the target chemical Metam-sodium (137-42-8) does not exhibit toxic nature upon repeated exposure by dermal route of exposure and hence is not likely to classify as per the criteria mentioned in CLP regulation.

Justification for classification or non-classification

Based on the data available for the target chemical Metam-sodium (137-42-8) does not exhibit toxic nature upon repeated exposure by oral, inhalation and dermal route of exposure and hence is not likely to classify as per the criteria mentioned in CLP regulation.