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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:
1.48 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):
50
Dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
74 mg/m³
Explanation for the modification of the dose descriptor starting point:

Starting point is OECD 422 study on Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivatives (ANS IP) by oral dosing in rats, resulting to a NOAEL of 30 mg/kg bw/day.

The corrected 8 hr inhalation NOAEC for workers is NOAEL * 1/0.38 * 6.7/10 (light exercise). Additionally a correction for differences between human and experimental exposure conditions of 1.4 is added (5 d/w versus experimental daily exposure): 8hr-NOAEC workers = NOAEL(30 mg/kg) * 1.76 * 1.4 = 74 mg/m3.

As described at toxicokinetics information, absorption via inhalation is considered to be complete (100%). In view of the very low vapour pressure is exposure via inhalation in principle only possible via aerosol or dust. In both cases most is expected to be deposited in the nose, throat and upper airways and will be subsequently swallowed following mucociliary transportation to pharynx. This results to no principal difference in absorption compared oral route. Profiling suggests that C7-alkyl naphthalene sulphonate is well absorbed, and higher absorption via inhalation is not obvious. Consequently, no additional factor 2 is applied.

AF for dose response relationship:
1
Justification:
No specific concerns; starting point is NOAEL and the effects show a dose response.
AF for differences in duration of exposure:
4
Justification:
Exposure duration was up to 54 days (until post-natal day 12) in-between a 28-day and 90-day study.
AF for interspecies differences (allometric scaling):
1
Justification:
Already included in NOAEC calculation
AF for other interspecies differences:
2.5
Justification:
Default (DNEL calculator).
AF for intraspecies differences:
5
Justification:
Default (DNEL calculator).
AF for the quality of the whole database:
1
Justification:
Available data derived from valid studies showing consistent results.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties. To this can be remarked that toxicity is mainly driven by local effects in stomach rather than systemic toxicity and effects at 200 mg/kg bw/day only involve a slight lower BW compared to control (-6%) in males, and an increased combined effects in stomach upon histopathological examinations in males. The NOAEL for actual systemic toxicity might well be much higher than 200 mg/kg bw/day. The use of a NOAEL of 30 mg/kg bw therefore adds to additional conservatism.
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:
0.21 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):
200
Dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
42 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

ECHA guidance assumes that absorption for dermal exposure is the same as for oral exposure, which is a worst case assumption. Starting point is OECD 422 study on Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivatives (ANS IP) by oral dosing in rats, resulting to a NOAEL of 30 mg/kg bw/day.

At this stage no data are available on dermal absorption. Naphthalene Sulfonates are not expected to easily pass the skin in view of its ionised form at physiological conditions. However, as this is not quantitatively evaluated, 100% dermal absorption is considered as conservative assumption.

The dermal NOAEL for workers is additionally corrected for differences between human and experimental exposure conditions with a factor of 1.4 (5 d/w versus experimental daily exposure): 8hr-NOAEC workers =

NOAEL(30 mg/kg) * 1.4 = 42 mg/kg bw/day.

AF for dose response relationship:
1
Justification:
No specific concerns; starting point is NOAEL and the effects show a clear dose response.
AF for differences in duration of exposure:
4
Justification:
Exposure duration was up to 54 days (until post-natal day 12) in-between a 28-day and 90-day study.
AF for interspecies differences (allometric scaling):
4
Justification:
A factor of 4 is applied based on ECHA guidance for allometric scaling of data from rats to humans.
AF for other interspecies differences:
2.5
Justification:
Default (DNEL calculator).
AF for intraspecies differences:
5
Justification:
Default (DNEL calculator).
AF for the quality of the whole database:
1
Justification:
Available data derived from valid studies showing consistent results.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties. To this can be remarked that toxicity is mainly driven by local effects in stomach rather than systemic toxicity and effects at 200 mg/kg bw/day only involve a slight lower BW compared to control (-6%) in males, and an increased combined effects in stomach upon histopathological examinations in males. The NOAEL for actual systemic toxicity might well be much higher than 200 mg/kg bw/day. The use of a NOAEL of 30 mg/kg bw therefore adds to additional conservatism.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

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

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - workers

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.22 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):
100
Dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
22 mg/m³
Explanation for the modification of the dose descriptor starting point:

Starting point is OECD 422 study on Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivatives (ANS IP) by oral dosing in rats, resulting to a NOAEL of 30 mg/kg bw/day.

The corrected 8 hr inhalation NOAEC for general population is NOAEL(30 mg/kg) * 1/1.35 (for 60 kg subject) mg/m3 = 22.2 mg/m3.

As described at toxicokinetics information, absorption via inhalation is considered to be complete (100%). In view of the very low vapour pressure is exposure via inhalation in principle only possible via aerosol or dust. In both cases most is expected to be deposited in the nose, throat and upper airways and will be subsequently swallowed following mucociliary transportation to pharynx. This results to no principal difference in absorption compared oral route. Profiling suggests that C7-alkyl naphthalene sulphonate is well absorbed, and higher absorption via inhalation is not obvious. Consequently, no additional factor 2 is applied.

AF for dose response relationship:
1
Justification:
No specific concerns; starting point is NOAEL and the effects show a clear dose response.
AF for differences in duration of exposure:
4
Justification:
Exposure duration was up to 54 days (until post-natal day 12) in-between a 28-day and 90-day study.
AF for interspecies differences (allometric scaling):
1
Justification:
Already included in LOAEC/NOAEC calculation
AF for other interspecies differences:
2.5
Justification:
Default (DNEL calculator).
AF for intraspecies differences:
10
Justification:
Default (DNEL calculator).
AF for the quality of the whole database:
1
Justification:
Available data derived from valid studies showing consistent results.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties. To this can be remarked that toxicity is mainly driven by local effects in stomach rather than systemic toxicity and effects at 200 mg/kg bw/day only involve a slight lower BW compared to control (-6%) in males, and an increased combined effects in stomach upon histopathological examinations in males. The NOAEL for actual systemic toxicity might well be much higher than 200 mg/kg bw/day. The use of a NOAEL of 30 mg/kg bw therefore adds to additional conservatism.
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:
0.075 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):
400
Dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

ECHA guidance assumes that absorption for dermal exposure is the same as for oral exposure, which is a worst case assumption. Starting point is OECD 422 study on Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivatives (ANS IP) by oral dosing in rats, resulting to a NOAEL of 30 mg/kg bw/day.

At this stage no data are available on dermal absorption. Alkyl Naphthalene Sulfonates are not expected to easily pass the skin in view of its ionised form at physiological conditions. However, as this is not quantitatively evaluated, 100% dermal absorption is considered as conservative assumption.

AF for dose response relationship:
1
Justification:
No specific concerns; starting point is NOAEL and the effects show a clear dose response.
AF for differences in duration of exposure:
4
Justification:
Exposure duration was up to 54 days (until post-natal day 12) in-between a 28-day and 90-day study.
AF for interspecies differences (allometric scaling):
4
Justification:
A factor of 4 is applied based on ECHA guidance for allometric scaling of data from rats to humans.
AF for other interspecies differences:
2.5
Justification:
Default (DNEL calculator).
AF for intraspecies differences:
10
Justification:
Default (DNEL calculator).
AF for the quality of the whole database:
1
Justification:
Available data derived from valid studies showing consistent results.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties. To this can be remarked that toxicity is mainly driven by local effects in stomach rather than systemic toxicity and effects at 200 mg/kg bw/day only involve a slight lower BW compared to control (-6%) in males, and an increased combined effects in stomach upon histopathological examinations in males. The NOAEL for actual systemic toxicity might well be much higher than 200 mg/kg bw/day. The use of a NOAEL of 30 mg/kg bw therefore adds to additional conservatism.
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:
DNEL (Derived No Effect Level)
Value:
0.075 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):
400
Dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
30 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

Starting point is OECD 422 study by oral dosing in rats, resulting to a NOAEL of 30 mg/kdbw/day based on minor histopathological findings in the stomach above this level. No route-to-route extrapolation is needed.

AF for dose response relationship:
1
Justification:
No specific concerns; starting point is NOAEL and the effects show a clear dose response.
AF for differences in duration of exposure:
4
Justification:
Exposure duration was up to 54 days (until post-natal day 12) in-between a 28-day and 90-day study.
AF for interspecies differences (allometric scaling):
4
Justification:
A factor of 4 is applied based on ECHA guidance for allometric scaling of data from rats to humans.
AF for other interspecies differences:
2.5
Justification:
Default (DNEL calculator).
AF for intraspecies differences:
10
Justification:
Default (DNEL calculator).
AF for the quality of the whole database:
1
Justification:
Available data derived from valid studies showing consistent results.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties. To this can be remarked that toxicity is mainly driven by local effects in stomach rather than systemic toxicity and effects at 200 mg/kg bw/day only involve a slight lower BW compared to control (-6%) in males, and an increased combined effects in stomach upon histopathological examinations in males. The NOAEL for actual systemic toxicity might well be much higher than 200 mg/kg bw/day. The use of a NOAEL of 30 mg/kg bw therefore adds to additional conservatism.
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

C7-alkyl naphthalene sulphonate is only used in industrially and professional settings; no consumers uses have been identified. However, in order to be able to evaluate possible secondary exposures via environment, additionally long-term systemic DNELs for general population have been derived.