Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.7 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
By inhalation
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
25
Modified dose descriptor starting point:
NOAEC
Value:
17.6 mg/m³
Explanation for the modification of the dose descriptor starting point:
No inhalational study is available. A NOAEL of 10 mg/kg bw/d from a 90D oral toxicity study is converted to 7.9 mg/m3(10 mg/kg bw/d/0.38 m3/kg bw/d (rat inh vol for 8h) = 26.3 mg/m3and then further modified with a factor 6.7 m3/10 m3due to higher respiration volume during work. The modified starting point is then 17.6 mg/m3
AF for dose response relationship:
1
AF for differences in duration of exposure:
2
AF for interspecies differences (allometric scaling):
1
Justification:
iallometric scaling s not to be used as the dose level has been converted to inhalational concentration
AF for other interspecies differences:
2.5
AF for intraspecies differences:
5
AF for the quality of the whole database:
1
AF for remaining uncertainties:
1
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
acute toxicity
Route of original study:
By inhalation
DNEL related information
Explanation for the modification of the dose descriptor starting point:

Data from an acute inhalation toxicity study (OECD 436) is availabe, an LC50 > 5 mg/L was identified. Based on this result, no specific DNEL for acute toxocity is considered necessary as the long-term DNEL would sufficiently protect against high short term peak expposure as well.

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.1 mg/m³
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
DNEL derivation method:
other: ACGIH OEL value, read-across to hydrazine
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
acute toxicity
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.1 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):
100
Modified dose descriptor starting point:
NOAEL
Value:
10 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:
No dermal repeated dose toxicity studies are available. Data from a 90D oral toxicity study (OECD 408) is used where a NOAEL of 10 mg/kg bw/d was identified. As no data regarding skin absorption is available similar absorption after dermal exposes as after oral exposure is assumed as a worst-case scenario.
AF for dose response relationship:
1
AF for differences in duration of exposure:
2
AF for interspecies differences (allometric scaling):
4
AF for other interspecies differences:
2.5
AF for intraspecies differences:
5
AF for the quality of the whole database:
1
AF for remaining uncertainties:
1
Acute/short term exposure
Hazard assessment conclusion:
no DNEL required: short term exposure controlled by conditions for long-term
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
hazard unknown (no further information necessary)
Most sensitive endpoint:
sensitisation (skin)
Acute/short term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
Most sensitive endpoint:
sensitisation (skin)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
low hazard (no threshold derived)

Additional information - workers

OBSH is used as a blowing agent in industrial processing and for professional uses.

For systemic effects from long term inhalational exposure, no inhalational study is available. A DNEL of 0.7 mg/m3 was established based on a NOAEL of 10 mg/kg bw/d from an oral OECD 408 90D study.

For local effects in respiratory tract from long term inhalational exposure a DNEL of 0.1 mg/m3 is applicable based on a ACGIH TLV of 0.1 mg/m3 for OBSH derived to protect against effects from hydrazine liberated from hydrolysis of OBSH.

For systemic effects from long term dermal exposure, no dermal study is available. A DNEL of 0.1 mg/kg/d was established based on a NOAEL of 10 mg/kg bw/d from an oral OECD 408 90D study with rats.

Short term exposure is controlled by conditions for long-term exposure, therefore no DNEL has been established. Further, as OBSH has been identified as a skin sensitizer, strict control measures should apply.

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:
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

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

No hazard identification relevant for consumers and the general population as exposure to OBSH is considered neglible. OBSH is used as a blowing agent and during the foaming process, OBSH decomposes into nitrogen and 4,4-oxybis (benzenesulfonic acid) which is further transformed into polydithiophenyl ether and polymetric thiosulfonate. Therefore, a direct consumer exposure is not likely to occur since OBSH is not contained in final products.