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Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.41 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
25
Modified dose descriptor starting point:
NOAEC
DNEL value:
52.6 mg/m³
Explanation for the modification of the dose descriptor starting point:
NOAECcorr=NOAELoral*(1/0.38 m³/kg/d)*(ABSoral-rat/ABSinh-human)*(6.7 m³ (8h)/10 m³ (8h)) = 700 mg/kg/d*(1/0.38 m³/kg/d)*(0.5*1)*0.67=617 mg/m³. It is assumed that oral absorption rate is 50% of that of inhalation absorption. ABSoral/rat=oral absorption rate in rats, ABSinh./human=inhalation absorption rate in humans.
AF for dose response relationship:
1
Justification:
a true NOAEL is available
AF for differences in duration of exposure:
2
Justification:
extrapolation from subchronic to chronic
AF for interspecies differences (allometric scaling):
1
Justification:
not necessary for inhalation route
AF for other interspecies differences:
2.5
Justification:
default value for remaining differences
AF for intraspecies differences:
5
Justification:
default value for workers
AF for the quality of the whole database:
1
Justification:
good quality data available
AF for remaining uncertainties:
1
Justification:
the data provided covers the tonnage band
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown (no further information necessary)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
hazard unknown (no further information necessary)
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown (no further information necessary)
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
2.06 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
175
Modified dose descriptor starting point:
NOAEL
DNEL value:
360 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:
It is assumed that oral and dermal absorption rates are equal.
AF for dose response relationship:
1
Justification:
a true NOAEL is available
AF for differences in duration of exposure:
2
Justification:
extrapolation from subchronic to chronic
AF for interspecies differences (allometric scaling):
7
Justification:
default value for mice
AF for other interspecies differences:
2.5
Justification:
default value for remaining differences
AF for intraspecies differences:
5
Justification:
default value for workers
AF for the quality of the whole database:
1
Justification:
good quality data available
AF for remaining uncertainties:
1
Justification:
the data provided covers the tonnage band
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.004 mg/cm²
Most sensitive endpoint:
sensitisation (skin)
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
15
Dose descriptor:
other: LOEL (rat) = 11.25 mg/kg bw/day
AF for dose response relationship:
3
Justification:
EC3/NOAEL extrapolation
AF for differences in duration of exposure:
1
Justification:
no time-dependence expected for local skin irritation
AF for interspecies differences (allometric scaling):
1
Justification:
not necessary for local effects
AF for other interspecies differences:
1
Justification:
not necessary for local effects
AF for intraspecies differences:
5
Justification:
default for workers
AF for the quality of the whole database:
1
Justification:
good quality data available
AF for remaining uncertainties:
1
Justification:
the data provided covers the tonnage band
Acute/short term exposure
Hazard assessment conclusion:
no DNEL required: short term exposure controlled by conditions for long-term
Most sensitive endpoint:
sensitisation (skin)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

Long-term exposure, dermal, systemic effects

In 90-day studies performed in rats and mice with sodium thioglycolate, the dermal NOAELs for systemic toxicity were higher than 180 and 360 mg/kg bw/day, respectively. The NOAEL > 360 mg/kg bw/day in mice is selected as a relevant dose-descriptor.

Step 1) Relevant dose descriptor

NOAELMouse> 360 mg/kg bw/day

Step 2) Modification of starting point

Correction for substance differences in dermal absorption

 

1

Step 3) Assessment factors

Interspecies

Intraspecies

Exposure duration

Dose response

Quality of database

 

2.5 x 7

5

2

1

1

DNEL Value

> 2.06 mg/kg bw/day

(360 x 1/(2.5 x 7 x 5 x 2 x 1 x 1))

Long-term exposure, inhalation, systemic effects

In a 90-day oral toxicity study performed in rats with sodium thioglycolate, the NOAEL for systemic toxicity was 20 mg/kg bw/day.

No difference between oral and inhalation absorption is assumed.

Step 1) Relevant dose descriptor

NOAELRat= 20 mg/kg bw/day

Step 2) Modification of starting point

Conversion into inhalatory NOAEC (in mg/m³) by using an 8-hour standard respiratory volume for the rat

Correction for differences between oral and inhalation absorption

Correction for differences in 8-hour inhalative volumes between workers in rest and workers under light activity

 

 

0.38 m³ /kg bw

 

1

 

6.7 m³ / 10 m³

Step 3) Assessment factors

Interspecies

Intraspecies

Exposure duration

Dose response

Quality of database

 

2.5

5

2

1

1

DNEL Value

1.41 mg/m³

(20 x 1/0.38 x 1 x 6.7/10 x 1/(2.5 x 7 x 5 x 2 x 1 x 1))

Long-term exposure, dermal, local effects

1st approach based on sensitisation study:

It can be considered that the reddening seen after repeated dermal exposure is caused due to the sensitising potential of the thioglycolate anion.

2nd approach based on repead-dose toxicity:

In a 90-day dermal toxicity study perfomed in rats with sodium thioglycolate, the LOEL for local effects at the site of application (skin irritation) was 11.25 mg/kg bw.

Step 1) Relevant dose descriptor

LOELRat= 11.25 mg/kg bw/day

Step 2) Modification of starting point

Modification to LOEL for dermal irritation (in mg/cm²/day)

  

0.25 kg / 44.5 cm²

Step 3) Assessment factors

Interspecies (local effects)

Intraspecies

Exposure duration

Dose response (LOEL/NAEL extrapolation)

Quality of database

 

1

5

1

3

1

DNEL Value

0.004 mg/cm²/day

(11.25 x 0.25/44.5 x 1/(1 x 5 x 1 x 3 x 1))

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.9 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Dermal
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
200
Modified dose descriptor starting point:
NOAEL
DNEL value:
180 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:
It is assumed that oral and dermal absorption rates are equal.
AF for dose response relationship:
1
Justification:
no time-dependence expected for local skin irritation
AF for differences in duration of exposure:
2
Justification:
DNEL is based on an oral 90 day study
AF for interspecies differences (allometric scaling):
4
Justification:
experimental animal was rat
AF for other interspecies differences:
2.5
Justification:
ECHA default factor
AF for intraspecies differences:
10
Justification:
ECHA default factor
AF for the quality of the whole database:
1
Justification:
good quality data available
AF for remaining uncertainties:
1
Justification:
the data provided covers the tonnage band
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
sensitisation (skin)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
sensitisation (skin)
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
sensitisation (skin)

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population