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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:
17.6 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
Value:
441 mg/m³
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
25 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
100
Modified dose descriptor starting point:
NOAEL
Value:
2 500 mg/kg bw/day
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
low hazard (no threshold derived)

Additional information - workers

Short term exposure worker (systemic effects)

 

It is not possible to derive a DNEL for acute effects based on the available data. The acute toxicity of Thiodiglycol is low with respect to the oral and dermal routes of exposure. There is no risk to be expected from inhalative vapor exposure since IRT showed no effects.

 

Short term exposure worker (local effects)

Thiodiglycol is in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 classified as eye irritant (cat. 2). The performed guideline test is not providing dose-response data that could be used for the derivation of a DNEL.

According to the REACH guidance on information requirements and chemical safety assessment, Part E: Risk Characterisation, a qualitative risk characterisation should be performed for this endpoint. In order to guarantee "adequately control of risks", it is necessary to stipulate risk management measures that prevent exposure.

 

Long term exposure worker (systemic effects)

Inhalatory and dermal

The DNELs for inhalatory and dermal long term exposure are derived from the NOAEL obtained in an oral repeated dose study (Angerhofer et al., 1997). In this 90-day gavage study (doses: 0, 50, 500, 5000 mg/kg bw/day), effects on body and kidney weight (without a histopathological correlate) as well as altered parameters of the urine analysis were observed in males and females at 5000 mg/kg bw/day. A dose level of 500 mg/kg bw/day is considered as NOAEL.

Exposure by inhalation

Modification into a correct starting point:

Relevant dose descriptor (NOAEL): 500 mg/kg bw/d

Standard respiratory volume of the rat (sRVrat) for 8 hours: 0.38 m³/kg bw

Oral absorption of the rat / inhalation absorption of humans (ABSoral-rat / ABSinh-human): 0.5

Standard respiratory volume of humans (sRVhuman) for 8 hours: 6.7 m³

Worker respiratory volume (wRV) for 8 hours with light physical activity: 10 m³

 

Corrected inhalatory NOAEC for workers

= 500 mg/kg bw/d * (1 / 0.38 m³/kg bw) * 0.5 * (6.7 m³/10 m³)

= 441 mg/m³

 

Use of assessment factors: 25

Interspecies: no allometric scaling factor is applied because an oral-to-inhalation route extrapolation is performed.

Intraspecies AF (worker): 5

Exposure duration AF: 2

Remaining differences AF: 2.5

 

In conclusion, long term systemic inhalation DNEL, workers = 17.6 mg/m³.

Dermal exposure

 

Modification into a correct starting point:

In in vitro experiments using pig skin, the percutaneous absorption was 20% after application of radiolabelled thiodiglycol in acetone solution (Reifenrath et al., 2002).

Corrected dermal NOAEL for workers

= 500 mg/kg bw/d * (1 / 0.2)

= 2500 mg/kg bw

 

Step 3: Use of assessment factors: 100

Interspecies AF, allometric scaling (rat to human): 4

Intraspecies AF (worker): 5

Exposure duration AF: 2

Remaining differences AF: 2.5

 

In conclusion, long term systemic dermal DNEL, workers = 25 mg/kg bw/day.

 

Long term exposure worker (local effects)

Thiodiglycol is in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 classified as eye irritant (cat. 2). The available data are not suitable for the derivation of a DNEL.

According to the REACH guidance on information requirements and chemical safety assessment, Part E: Risk Characterisation, a qualitative risk characterisation should be performed for this endpoint. In order to guarantee "adequately control of risks", it is necessary to stipulate risk management measures that prevent exposure.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
4.3 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
Overall assessment factor (AF):
50
Modified dose descriptor starting point:
NOAEC
Value:
217 mg/m³
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
12.5 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
200
Modified dose descriptor starting point:
NOAEL
Value:
2 500 mg/kg bw/day
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
2.5 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
200
Modified dose descriptor starting point:
NOAEL
Value:
500 mg/kg bw/day
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
low hazard (no threshold derived)

Additional information - General Population

Short term exposure general population (systemic effects)

 

It is not possible to derive a DNEL for acute effects based on the available data. The acute toxicity of Thiodiglycol is low with respect to the oral and dermal routes of exposure. There is no risk to be expected from inhalative vapor exposure since IRT showed no effects.

 

Short term exposure general population (local effects)

Thiodiglycol is in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 classified as eye irritant (cat. 2). The performed guideline test is not providing dose-response data that could be used for the derivation of a DNEL.

 

Long term exposure general population (systemic effects)

Inhalatory, dermal and oral

The DNELs for inhalatory, dermal and oral long term exposure are derived from the NOAEL obtained in an oral repeated dose study (Angerhofer et al., 1997). In this 90-day gavage study (doses: 0, 50, 500, 5000 mg/kg bw/day), effects on body and kidney weight (without a histopathological correlate) as well as altered parameters of the urine analysis were observed in males and females at 5000 mg/kg bw/day. A dose level of 500 mg/kg bw/day is considered as NOAEL.

Exposure by inhalation

Modification into a correct starting point:

Relevant dose descriptor (NOAEL): 500 mg/kg bw/d

Standard respiratory volume of the rat (sRVrat) for 24 hours: 1.15 m³/kg bw

Oral absorption of the rat / inhalation absorption of humans (ABSoral-rat / ABSinh-human): 0.5

 

Corrected inhalatory NOAEC for general population

= 500 mg/kg bw/d * (1 / 1.15 m³/kg bw/d) * 0.5

= 217 mg/m³

 

Use of assessment factors: 50

Interspecies: no allometric scaling factor is applied because an oral-to-inhalation route extrapolation is performed.

Intraspecies AF (general population): 10

Exposure duration AF: 2

Remaining differences AF: 2.5

 

In conclusion, long term systemic inhalation DNEL, general population = 4.3 mg/m³.

Dermal exposure

 

Modification into a correct starting point:

In in vitro experiments using pig skin,the percutaneous absorption was 20% after application of radiolabelled thiodiglycol in acetone solution (Reifenrath et al., 2002).

Corrected dermal NOAEL for general population

= 500 mg/kg bw/d * (1 / 0.2)

= 2500 mg/kg bw

Use of assessment factors: 200

Interspecies AF, allometric scaling (rat to human): 4

Intraspecies AF (general population): 10

Exposure duration AF: 2

Remaining differences AF: 2.5

 

In conclusion, long term systemic dermal DNEL, general population = 12.5 mg/kg bw/day.

Oral exposure

 

Modification into a correct starting point:

No modification of starting point necessary (NOAEL = 500 mg/kg bw/d)

 

Use of assessment factors: 200

Interspecies AF, allometric scaling (rat to human): 4

Intraspecies AF (general population): 10

Exposure duration AF: 2

Remaining differences AF: 2.5

 

In conclusion, long term systemic oral DNEL, general population = 2.5 mg/kg bw/day.

 

Long term exposure general population (local effects)

Thiodiglycol is in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 classified as eye irritant (cat. 2). The available data are not suitable for the derivation of a DNEL.