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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
6.64 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
12.5
Dose descriptor starting point:
NOAEL
Value:
94.2 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
83 mg/m³
Explanation for the modification of the dose descriptor starting point:

The calculation of the DNEL is based on an oral NOAEL observed in a developmental toxicity study in rats with the structural analogue boric acid (OECD 414; Price, 1996). The estimated NOAEL for boron (MW = 10.8 g/mol) observed in this study is 9.6 mg/kg bw/day which leads to a corrected NOAEL for boron orthophosphate (MW = 106.0 g/mol) of 94.2 mg/kg bw/day.

To correct the interspecies difference between rat and human the NOAEL has to be corrected as follows:

Corrected starting point for the inhalative route for workers:

= NOAEL(oral) * (1/0.38 m³/kg bw/day) * (ABSoral-rat/ABSinh-human) * 6.7 m³ (8h) /10 m³ (8h)

= 94.2 mg/kg bw/day * (1/0.38 m³/kg bw/day) * (1/2) * 0.67 m³ = 83.0 mg/m³

As worst case as recommended in the ECHA Guidance R.8 (2012), it is assumed that oral absorption rate is 50% of that of of inhalation absorption.

(ABSoral-rat = oral absorption in rats, ABSinh-human = inhalation absorption rate in humans)

Thus, the corrected starting point for workers was 83.0 mg/m³ for inhalation.

AF for dose response relationship:
1
Justification:
The dose descriptor starting point is based on a NOAEL.
AF for differences in duration of exposure:
1
Justification:
Even though the DNEL is derived from a sub-acute study it can be assumed that this is also sufficient for long-term duration because a BMDL05 derived for boric acid (Allen et al., 1996) from several developmental toxicity studies was calculated to be 10.3 mg boron/kg bw/day which is close to the NOAEL derived from the developmental toxicity study (9.6 mg boron/kg bw/day).

Allen et al., 1996; Benchmark Dose Analysis of Developmental Toxicity in Rats Exposed to Boric Acid; Fundamental And Applied Toxicology 32, pp. 194-204
AF for interspecies differences (allometric scaling):
1
Justification:
AF not used for inhalation route.
AF for other interspecies differences:
2.5
Justification:
Default value according to ECHA REACH Guidance.
AF for intraspecies differences:
5
Justification:
Default value for workers according to ECHA REACH Guidance.
AF for the quality of the whole database:
1
Justification:
The DNEL is based on a high-quality study.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
acute toxicity
Route of original study:
By inhalation
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
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:
188.4 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
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:
94.2 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
9 420 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The calculation of the DNEL is based on an oral NOAEL observed in a developmental toxicity study in rats with the structural analogue boric acid (OECD 414; Price, 1996). The estimated NOAEL for boron (MW = 10.8 g/mol) observed in this study is 9.6 mg/kg bw/day which leads to a corrected NOAEL for boron orthophosphate (MW = 106.0 g/mol) of 94.2 mg/kg bw/day.

To correct the interspecies difference between rat and human the NOAEL has to be corrected as follows:

Corrected starting point for the dermal route for workers:

Dermal NOAEL = oral NOAEL*ABS(oral)/ABS(dermal) = 94.2 mg/kg bw/day *(100%/1%) = 18840 mg/kg bw/day. For boric acid and borat compounds a dermal absorption rate of 0.5% is agreed. QSAR calculation (Dermwin) estimate a dermal absorption rate for boron orthophosphate of 1%.

AF for dose response relationship:
1
Justification:
The dose descriptor starting point is based on a NOAEL.
AF for differences in duration of exposure:
1
Justification:
Even though the DNEL is derived from a sub-acute study it can be assumed that this is also sufficient for long-term duration because a BMDL05 derived for boric acid (Allen et al., 1996) from several developmental toxicity studies was calculated to be 10.3 mg boron/kg bw/day which is close to the NOAEL derived from the developmental toxicity study (9.6 mg boron/kg bw/day).

Allen et al., 1996; Benchmark Dose Analysis of Developmental Toxicity in Rats Exposed to Boric Acid; Fundamental And Applied Toxicology 32, pp. 194-204
AF for interspecies differences (allometric scaling):
4
Justification:
The experimental animal was a rat.
AF for other interspecies differences:
2.5
Justification:
Default value according to ECHA REACH Guidance.
AF for intraspecies differences:
5
Justification:
Default value for workers according to ECHA REACH Guidance.
AF for the quality of the whole database:
1
Justification:
The DNEL is based on a high-quality study.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties.
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.64 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
25
Dose descriptor starting point:
NOAEL
Value:
94.2 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
41 mg/m³
Explanation for the modification of the dose descriptor starting point:

The calculation of the DNEL is based on an oral NOAEL observed in a developmental toxicity study in rats with the structural analogue boric acid (OECD 414; 1996). The estimated NOAEL for boron (MW = 10.8 g/mol) observed in this study is 9.6 mg/kg bw/day which leads to a corrected NOAEL for boron orthophosphate (MW = 106.0 g/mol) of 94.2 mg/kg bw/day.

Corrected starting point for the inhalative route for general population:

= NOAELoral * (1/1.15 m³/kg bw/day (24h)) * (ABSoral-rat / ABSinh-human)

= 94.2 mg/kg bw/day * (1/1.15 m³/kg bw/day) * (1/2) = 41.0 mg/m³

As worst case as recommended in the ECHA Guidance R.8 (2012), it is assumed that oral absorption rate is 50% of that of of inhalation absorption.

(ABSoral-rat = oral absorption in rats, ABSinh-human = inhalation absorption rate in humans)

Thus, the corrected starting point for general population was 41.0 mg/m³ for inhalation.

AF for dose response relationship:
1
Justification:
The dose descriptor starting point is based on a NOAEL.
AF for differences in duration of exposure:
1
Justification:
Even though the DNEL is derived from a sub-acute study it can be assumed that this is also sufficient for long-term duration because a BMDL05 derived for boric acid (Allen et al., 1996) from several developmental toxicity studies was calculated to be 10.3 mg boron/kg bw/day which is close to the NOAEL derived from the developmental toxicity study (9.6 mg boron/kg bw/day).

Allen et al., 1996; Benchmark Dose Analysis of Developmental Toxicity in Rats Exposed to Boric Acid; Fundamental And Applied Toxicology 32, pp. 194-204
AF for interspecies differences (allometric scaling):
1
Justification:
AF not used for inhalation route.
AF for other interspecies differences:
2.5
Justification:
Default value according to ECHA REACH Guidance.
AF for intraspecies differences:
10
Justification:
Default value for general population according to ECHA REACH Guidance.
AF for the quality of the whole database:
1
Justification:
The DNEL is based on a high-quality study.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
acute toxicity
Route of original study:
By inhalation
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
acute toxicity
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
94.2 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
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:
94.2 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
9 420 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The calculation of the DNEL is based on an oral NOAEL observed in a developmental toxicity study in rats with the structural analogue boric acid (OECD 414; Price, 1996). The estimated NOAEL for boron (MW = 10.8 g/mol) observed in this study is 9.6 mg/kg bw/day which leads to a corrected NOAEL for boron orthophosphate (MW = 106.0 g/mol) of 94.2 mg/kg bw/day.

To correct the interspecies difference between rat and human the NOAEL has to be corrected as follows:

Corrected starting point for the dermal route for workers:

Dermal NOAEL = oral NOAEL*ABS(oral)/ABS(dermal) = 94.2 mg/kg bw/day *(100%/1%) = 18840 mg/kg bw/day. For boric acid and borat compounds a dermal absorption rate of 0.5% is agreed. QSAR calculation (Dermwin) estimate a dermal absorption rate for boron orthophosphate of 1%

AF for dose response relationship:
1
Justification:
The dose descriptor starting point is based on a NOAEL.
AF for differences in duration of exposure:
1
Justification:
Even though the DNEL is derived from a sub-acute study it can be assumed that this is also sufficent for long-term duration because a BMDL05 derived for boric acid (Allen et al., 1996) from several developmental toxicity studies was calculated to be 10.3 mg boron/kg bw/day which is close to the NOAEL derived from the developmental toxicity study (9.6 mg boron/kg bw/day).

Allen et al., 1996; Benchmark Dose Analysis of Developmental Toxicity in Rats Exposed to Boric Acid; Fundamental And Applied Toxicology 32, pp. 194-204
AF for interspecies differences (allometric scaling):
4
Justification:
The experimental animal was a rat.
AF for other interspecies differences:
2.5
Justification:
Default value according to ECHA REACH Guidance.
AF for intraspecies differences:
10
Justification:
Default value for general population according to ECHA REACH Guidance.
AF for the quality of the whole database:
1
Justification:
The DNEL is based on a high-quality study.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties.
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.94 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
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:
94.2 mg/kg bw/day
AF for dose response relationship:
1
Justification:
The dose descriptor starting point is based on a NOAEL.
AF for differences in duration of exposure:
1
Justification:
Even though the DNEL is derived from a sub-acute study it can be assumed that this is also sufficient for long-term duration because a BMDL05 derived for boric acid (Allen et al., 1996) from several developmental toxicity studies was calculated to be 10.3 mg boron/kg bw/day which is close to the NOAEL derived from the developmental toxicity study (9.6 mg boron/kg bw/day).

Allen et al., 1996; Benchmark Dose Analysis of Developmental Toxicity in Rats Exposed to Boric Acid; Fundamental And Applied Toxicology 32, pp. 194-204
AF for interspecies differences (allometric scaling):
4
Justification:
The experimental animal was a rat.
AF for other interspecies differences:
2.5
Justification:
Default value according to ECHA REACH Guidance.
AF for intraspecies differences:
10
Justification:
Default value for general population according to ECHA REACH Guidance.
AF for the quality of the whole database:
1
Justification:
The DNEL is based on a high-quality study.
AF for remaining uncertainties:
1
Justification:
No remaining uncertainties.
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
acute toxicity
Route of original study:
Oral
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population