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Diss Factsheets

Administrative data

Workers - 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:
medium hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Workers - 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

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

No substance specific data on repeated dose toxicity is available for titanium carbide. Due to similar physico-chemical properties, similar transformation/dissolution results and similar in vitro bioaccessibility in synthetic body fluids compared to titanium dioxide, data from TiO2 can be used for read-across.

Available data from a chronic (2-year) oral repeated dose toxicity study with TiO2 in rats showed that the substance had no appreciable effect on body weights of rats of either sex. Other than white feces, there were no treatment-related clinical signs and no adverse effects up to 50,000 ppm in feed, corresponding to 3,500 mg/kg bw/day, which is above the recommended limit dose for a chronic study of 1,000 mg/kg bw/day. Survival of the rats at the end of the bioassay was not affected by the test chemical (IUCLID Section 7.5.1).

In addition, a bioelution test with titanium carbide showed no bioaccessibility in interstitial fluid and very low bioaccessibility (0.08%) under the very harsh conditions of lysosomal fluid. Therefore, no hazard is expected after inhalation exposure to titanium carbide.

In addition, no titanium release was detected after 12 hours in artificial perspiration fluid and therefore, no hazard is expected after dermal exposure to titanium carbide.

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:
DNEL (Derived No Effect Level)
Value:
35 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:
3 500 mg/kg bw/day
AF for dose response relationship:
1
AF for differences in duration of exposure:
1
Justification:
chronic study
AF for interspecies differences (allometric scaling):
4
Justification:
default
AF for other interspecies differences:
2.5
Justification:
default
AF for intraspecies differences:
10
Justification:
default (general population)
AF for the quality of the whole database:
1
AF for remaining uncertainties:
1
Justification:
no additional uncertainties 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 substance specific data on repeated dose toxicity is available for titanium carbide. Due to similar physico-chemical properties, similar transformation/dissolution results and similar in vitro bioaccessibility in synthetic body fluids compared to titanium dioxide, data from TiO2 can be used for read-across.

Available data from a chronic (2-year) oral repeated dose toxicity study with TiO2 in rats showed that the substance had no appreciable effect on body weights of rats of either sex. Other than white feces, there were no treatment-related clinical signs and no adverse effects up to 50,000 ppm in feed, corresponding to 3,500 mg/kg bw/day, which is above the recommended limit dose for a chronic study of 1,000 mg/kg bw/day. Survival of the rats at the end of the bioassay was not affected by the test chemical (IUCLID Section 7.5.1).

In addition, a bioelution test with titanium carbide showed no bioaccessibility in interstitial fluid and very low bioaccessibility (0.08%) under the very harsh conditions of lysosomal fluid. Therefore, no hazard is expected after inhalation exposure to titanium carbide.

In addition, no titanium release was detected after 12 hours in artificial perspiration fluid and therefore no hazard is expected after dermal exposure to titanium carbide. Low bioaccessibility of titanium was observed in simulated gastric fluid after 2 hours (0.21%) to 24 hours (0.56%), respectively, (IUCLID Section 7.1.1).

Therefore, the oral NOAEL of 3,500 mg of titanium dioxide/kg bw/d for chronic toxicity in rats is used as dose descriptor for the calculation of a DNEL for systemic effects for humans exposed orally to comparable titanium compounds, like titanium dioxide.