Titanium 2,2',2''-nitrilotrisethanolate

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

a short-term toxicity study by the oral route does not need to be conducted because an appropriate inhalation study is available and inhalation is the most appropriate route of administration as based on the provided thorough and rigorous exposure assessment

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Please provide information for all of the points below. Indicate if further information is included as attachment to the same record, or elsewhere in the dataset (insert links in 'Cross-reference' table)]

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
[Describe why the read-across can be performed (e.g. common functional group(s), common precursor(s)/breakdown product(s) or common mechanism(s) of action]

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
[Provide here, if relevant, additional information to that included in the Test material section of the source and target records]

3. ANALOGUE APPROACH JUSTIFICATION
[Summarise here based on available experimental data how these results verify that the read-across is justified]

4. DATA MATRIX

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)

GLP compliance:

yes

Specific details on test material used for the study:

Name of test material (as cited in study report): Triethanolamine; Substance No. 89/711
- Physical state: liquid/colourless
- Analytical purity: 98.9 %
- Date of manufacture: June 29, 1989
- Lot/batch No.: Probe 912
- Stability under test conditions: ensured
- Storage condition of test material: under nitrogen

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Source: Dr. K. Thomae GmbH, Biberach
- Age at study initiation: 7 weeks
- mean weight at study initiation: males: 239; females 168 g
- Fasting period before study: none
- Housing: individually
- Diet: KLIBA rat/mouse/hamster Iaboratory diet 24-343-4 10 mm pellets, KlingentalmuehIe AG, Kaiseraugst, Switzerland ad libitum
- Water: tap water ad libitum
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

The substance to be tested was supplied to a two-component atomizer by means of a continuous infusion pump and was atomized with compressed air. Having passed a glass separator, the liquid aerosol was diluted with conditioned blast air which was conducted via a glass bottle filled with bidist. water for humidification and was supplied to the exposure apparatus. In order to decrease the viscosity of the substance the two-component atomizers were warmed.
The following amounts of air were set:

Test group Compressed air [m³/h] Blast air [m³/h] Exhaused air [m³/h]
0 - 3.0 ± 0.3 2.7 ± 0.3
1 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3
2 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3
3 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3

Test group Substance flow atomizer [ml/h] Atomizer temperature [° C]
1 0.2 38.9 – 41.2
2 1.2 – 4.0 38.7 – 39.9
3 20 - 35 38.2 – 39.9

Head-nose exposure system
The head - nose exposure technique was preferably selected for this inhalation study to minimize fur contamination of the animals with the substance, which cannot be avoided during whole-body exposure. Fur contamination may lead to an additional dermal- and oral uptake (animals preen as their fur becomes contaminited). Thus an estimation of a nominal dose, taken up by the animals and its correlation to a toxic effect becomes more difficult.

Furthermore, by using the dynamic mode of operation with a Iow-volume chamber, the equilibrium characteristic of this exposure technique is favorable: t99 (the time to reach 99% of the final target concentraiion) is shorter as compared with whole - body chambers with a higher chamber volume.

The aerosol was generated inside an aerodynamic exposure appalatus (INA 20; volume V ~ 55 I, BASF Aktiengesellschaft). The apparatus consists of a cylindrical inhalation chamber of stainless steel sheeting and coneshaped outlets and inlets. The rats were restrained in exposure tubes (glass tubes), their snouts projected into the inhalation chamber and they thus inhaled the aerosol. The apparatus was also connected to an exhaust air system. The exhaust air system was set lower than the supply air system (positive pressure). This ensured that the aerosol in the breathing zones of the animals was not diluted by laboratory air.

In order to accustom the animals to the exposure conditions they were exposed to supply air in head-only exposure systems under comparable flow conditions on 5 days before the exposure period ( preflow period) . Then alI test groups were exposed for 6 hours on workdays over a time period of 28 days (285 days test). The number of exposures was 20.
The animals did not have access to water or feed during the exposure.

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

28 days

Frequency of treatment:

6 hrs/day, 5 days/week

Dose / conc.:

0.02 mg/L air (analytical)

Dose / conc.:

0.1 mg/L air (analytical)

Dose / conc.:

0.5 mg/L air (analytical)

No. of animals per sex per dose:

10

Control animals:

yes

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: one day before beginning of the exposure period and then once a week

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: 3 times on exposure days and once during the post observation period.

BODY WEIGHT: Yes
- Time schedule for examinations: at D1 and at D27

HAEMATOLOGY: Yes
- Time schedule for collection of blood: in the morning following last exposure
- Anaesthetic used for blood collection: No
- Animals fasted: No

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: in the morning following last exposure
- Animals fasted: Yes / No / Not specified
- How many animals: 5 animals / test group

URINALYSIS: Yes
- Time schedule for collection of urine:
- Metabolism cages used for collection of urine: Not specified
- Animals fasted: No
- Parameters checked in table [No.?] were examined.

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: performed on all animals before the beginning of exposure on study days 0, day 1, 8, 14, and 27 (last exposure).
- Battery of functions tested: tremors, convulsions, piloerection, lacrimation, secretion of pigmented tears, salivation, pupil size, diarrhea, vocalization, paresis, paralysis, ataxia, general appearance, body tone, posture, animal body (appearance), locomotor activity, respiration, urination, skin color, righting reflex, behavior, grip strenght, pupillary reflex, winking reflex, vision, audition, olfaction, sensitivity of the body surface, pain perception (hot plate test), , tail pinch, toe pinch, visual placing response,

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

During the whole study period the animals of test groups 0 to 2 showed no abnormal clinical signs and findings.
Reddish crusts on nasal edges (blood test positive) were detected in the animals of test group 3 after exposure during the second half of exposure period (males on days 21 to 23, 26 and 27, females on days 14 to 16, 20 to 23, 26 and 27).

Mortality:

no mortality observed

Description (incidence):

No deaths were recorded throughout the study.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Body weight and body weight change of male and female animals from alI test groups showed no statistically significant difference when compared to the control group

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

No substance-induced changes were observed in the hematological parameters or in clotting analysis of both sexes.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

No substance-induced changes were observed in the enzyme activities or the blood chemistry parameters of both sexes.

Urinalysis findings:

not specified

Behaviour (functional findings):

effects observed, non-treatment-related

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Neuropathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Local effects were characterized histopathologically by focal inflammatory changes in the submucosa of the larynx region, which seems to be the most sensitive part of the respiratory tract after aerosol exposure to Triethanolamine. There was a tendency to concentration dependent increase in incidence and severity of the lesion from mid to high concentration in both sexes. The effect was found in females to a lesser extent. In this sex 0.02 ng/l did not cause larynx irritation anymore. In male animals however minimal to slight effects were observed in the low concentration similar to the mid
concentration. Because of this simiIar grade of the lesion it is concluded that just below 0.02 ng/l no irritation should be present anymore

Histopathological findings: neoplastic:

no effects observed

Other effects:

not examined

Key result

Dose descriptor:

NOAEC

Remarks:

systemic effects

Effect level:

0.5 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed at the highest concentration tested

Key result

Dose descriptor:

NOAEC

Remarks:

local effects

Effect level:

0.02 mg/L air

Based on:

test mat.

Sex:

female

Basis for effect level:

histopathology: non-neoplastic

Remarks on result:

other:

Remarks:

irritation of the upper respiratory tract

Key result

Dose descriptor:

LOAEC

Remarks:

local effects

Effect level:

<= 0.02 mg/L air

Based on:

test mat.

Sex:

male

Basis for effect level:

histopathology: non-neoplastic

Remarks on result:

other:

Remarks:

focal inflammatory changes in the submucosa of the larynx

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

0.2 mg/L air

System:

respiratory system: upper respiratory tract

Organ:

larynx

Treatment related:

yes

Dose response relationship:

yes

Conclusions:

The LOAEC (local effects) was established to be 0.02 mg/litre (equivalent to23 mg/kg bw/day), based on the minimal to slight effects seen in the larynx of males.The NOAEC (systemic effects) was established to be0.5 mg/litre (equivalentto 575 mg/kg bw/day), based on the absence of effects at the highest dose tested.

In a sub-acute 28-day inhalation toxicity study (OECD 412),rats exposed to TEA for 6 hours/dayand 5 days/week displayed concentration-dependant focal inflammatory changes in the submucosaof the larynx. There were no systemic findings.

Executive summary:

In a sub-acute 28-day inhalation toxicity study (OECD 412), rats exposed to TEA for 6 hours/day and 5 days/week displayed concentration-dependant focal inflammatory changes in the submucosa of the larynx. There were no systemic findings.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEC

500 mg/m³

Study duration:

subacute

Species:

rat

System:

respiratory system: upper respiratory tract

Organ:

larynx

Repeated dose toxicity: inhalation - local effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Please provide information for all of the points below. Indicate if further information is included as attachment to the same record, or elsewhere in the dataset (insert links in 'Cross-reference' table)]

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
[Describe why the read-across can be performed (e.g. common functional group(s), common precursor(s)/breakdown product(s) or common mechanism(s) of action]

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
[Provide here, if relevant, additional information to that included in the Test material section of the source and target records]

3. ANALOGUE APPROACH JUSTIFICATION
[Summarise here based on available experimental data how these results verify that the read-across is justified]

4. DATA MATRIX

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)

GLP compliance:

yes

Specific details on test material used for the study:

Name of test material (as cited in study report): Triethanolamine; Substance No. 89/711
- Physical state: liquid/colourless
- Analytical purity: 98.9 %
- Date of manufacture: June 29, 1989
- Lot/batch No.: Probe 912
- Stability under test conditions: ensured
- Storage condition of test material: under nitrogen

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Source: Dr. K. Thomae GmbH, Biberach
- Age at study initiation: 7 weeks
- mean weight at study initiation: males: 239; females 168 g
- Fasting period before study: none
- Housing: individually
- Diet: KLIBA rat/mouse/hamster Iaboratory diet 24-343-4 10 mm pellets, KlingentalmuehIe AG, Kaiseraugst, Switzerland ad libitum
- Water: tap water ad libitum
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

The substance to be tested was supplied to a two-component atomizer by means of a continuous infusion pump and was atomized with compressed air. Having passed a glass separator, the liquid aerosol was diluted with conditioned blast air which was conducted via a glass bottle filled with bidist. water for humidification and was supplied to the exposure apparatus. In order to decrease the viscosity of the substance the two-component atomizers were warmed.
The following amounts of air were set:

Test group Compressed air [m³/h] Blast air [m³/h] Exhaused air [m³/h]
0 - 3.0 ± 0.3 2.7 ± 0.3
1 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3
2 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3
3 1.5 ± 0.3 1.5 ± 0.3 2.7 ± 0.3

Test group Substance flow atomizer [ml/h] Atomizer temperature [° C]
1 0.2 38.9 – 41.2
2 1.2 – 4.0 38.7 – 39.9
3 20 - 35 38.2 – 39.9

Head-nose exposure system
The head - nose exposure technique was preferably selected for this inhalation study to minimize fur contamination of the animals with the substance, which cannot be avoided during whole-body exposure. Fur contamination may lead to an additional dermal- and oral uptake (animals preen as their fur becomes contaminited). Thus an estimation of a nominal dose, taken up by the animals and its correlation to a toxic effect becomes more difficult.

Furthermore, by using the dynamic mode of operation with a Iow-volume chamber, the equilibrium characteristic of this exposure technique is favorable: t99 (the time to reach 99% of the final target concentraiion) is shorter as compared with whole - body chambers with a higher chamber volume.

The aerosol was generated inside an aerodynamic exposure appalatus (INA 20; volume V ~ 55 I, BASF Aktiengesellschaft). The apparatus consists of a cylindrical inhalation chamber of stainless steel sheeting and coneshaped outlets and inlets. The rats were restrained in exposure tubes (glass tubes), their snouts projected into the inhalation chamber and they thus inhaled the aerosol. The apparatus was also connected to an exhaust air system. The exhaust air system was set lower than the supply air system (positive pressure). This ensured that the aerosol in the breathing zones of the animals was not diluted by laboratory air.

In order to accustom the animals to the exposure conditions they were exposed to supply air in head-only exposure systems under comparable flow conditions on 5 days before the exposure period ( preflow period) . Then alI test groups were exposed for 6 hours on workdays over a time period of 28 days (285 days test). The number of exposures was 20.
The animals did not have access to water or feed during the exposure.

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

28 days

Frequency of treatment:

6 hrs/day, 5 days/week

Dose / conc.:

0.02 mg/L air (analytical)

Dose / conc.:

0.1 mg/L air (analytical)

Dose / conc.:

0.5 mg/L air (analytical)

No. of animals per sex per dose:

10

Control animals:

yes

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: one day before beginning of the exposure period and then once a week

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: 3 times on exposure days and once during the post observation period.

BODY WEIGHT: Yes
- Time schedule for examinations: at D1 and at D27

HAEMATOLOGY: Yes
- Time schedule for collection of blood: in the morning following last exposure
- Anaesthetic used for blood collection: No
- Animals fasted: No

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: in the morning following last exposure
- Animals fasted: Yes / No / Not specified
- How many animals: 5 animals / test group

URINALYSIS: Yes
- Time schedule for collection of urine:
- Metabolism cages used for collection of urine: Not specified
- Animals fasted: No
- Parameters checked in table [No.?] were examined.

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: performed on all animals before the beginning of exposure on study days 0, day 1, 8, 14, and 27 (last exposure).
- Battery of functions tested: tremors, convulsions, piloerection, lacrimation, secretion of pigmented tears, salivation, pupil size, diarrhea, vocalization, paresis, paralysis, ataxia, general appearance, body tone, posture, animal body (appearance), locomotor activity, respiration, urination, skin color, righting reflex, behavior, grip strenght, pupillary reflex, winking reflex, vision, audition, olfaction, sensitivity of the body surface, pain perception (hot plate test), , tail pinch, toe pinch, visual placing response,

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

During the whole study period the animals of test groups 0 to 2 showed no abnormal clinical signs and findings.
Reddish crusts on nasal edges (blood test positive) were detected in the animals of test group 3 after exposure during the second half of exposure period (males on days 21 to 23, 26 and 27, females on days 14 to 16, 20 to 23, 26 and 27).

Mortality:

no mortality observed

Description (incidence):

No deaths were recorded throughout the study.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Body weight and body weight change of male and female animals from alI test groups showed no statistically significant difference when compared to the control group

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

No substance-induced changes were observed in the hematological parameters or in clotting analysis of both sexes.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

No substance-induced changes were observed in the enzyme activities or the blood chemistry parameters of both sexes.

Urinalysis findings:

not specified

Behaviour (functional findings):

effects observed, non-treatment-related

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Neuropathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Local effects were characterized histopathologically by focal inflammatory changes in the submucosa of the larynx region, which seems to be the most sensitive part of the respiratory tract after aerosol exposure to Triethanolamine. There was a tendency to concentration dependent increase in incidence and severity of the lesion from mid to high concentration in both sexes. The effect was found in females to a lesser extent. In this sex 0.02 ng/l did not cause larynx irritation anymore. In male animals however minimal to slight effects were observed in the low concentration similar to the mid
concentration. Because of this simiIar grade of the lesion it is concluded that just below 0.02 ng/l no irritation should be present anymore

Histopathological findings: neoplastic:

no effects observed

Other effects:

not examined

Key result

Dose descriptor:

NOAEC

Remarks:

systemic effects

Effect level:

0.5 mg/L air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed at the highest concentration tested

Key result

Dose descriptor:

NOAEC

Remarks:

local effects

Effect level:

0.02 mg/L air

Based on:

test mat.

Sex:

female

Basis for effect level:

histopathology: non-neoplastic

Remarks on result:

other:

Remarks:

irritation of the upper respiratory tract

Key result

Dose descriptor:

LOAEC

Remarks:

local effects

Effect level:

<= 0.02 mg/L air

Based on:

test mat.

Sex:

male

Basis for effect level:

histopathology: non-neoplastic

Remarks on result:

other:

Remarks:

focal inflammatory changes in the submucosa of the larynx

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

0.2 mg/L air

System:

respiratory system: upper respiratory tract

Organ:

larynx

Treatment related:

yes

Dose response relationship:

yes

Conclusions:

The LOAEC (local effects) was established to be 0.02 mg/litre (equivalent to23 mg/kg bw/day), based on the minimal to slight effects seen in the larynx of males.The NOAEC (systemic effects) was established to be0.5 mg/litre (equivalentto 575 mg/kg bw/day), based on the absence of effects at the highest dose tested.

In a sub-acute 28-day inhalation toxicity study (OECD 412),rats exposed to TEA for 6 hours/dayand 5 days/week displayed concentration-dependant focal inflammatory changes in the submucosaof the larynx. There were no systemic findings.

Executive summary:

In a sub-acute 28-day inhalation toxicity study (OECD 412), rats exposed to TEA for 6 hours/day and 5 days/week displayed concentration-dependant focal inflammatory changes in the submucosa of the larynx. There were no systemic findings.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LOAEC

200 mg/m³

Study duration:

subacute

Species:

rat

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

a short-term toxicity study does not need to be conducted because exposure of humans via the dermal route in production and/or use is not likely as based on the provided thorough and rigorous exposure assessment

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

a short-term toxicity study does not need to be conducted because exposure of humans via the dermal route in production and/or use is not likely as based on the provided thorough and rigorous exposure assessment

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Read-across data from the decomposition product (TEA) is used for assessment, because the target substance is hydrolytically unstable having the half-life less than 12 hours. TEA is the most relevant decomposition product of the target substance for CSA. TiO2 exists as solid insoluble precipitate having low bioavailability and possessing very low acute and long-term toxicity (US EPA, 1994; WHO, 1982). Thus, it is concluded that no further assessment of TiO2 is needed for repeated dose toxicity.

Repeated oral toxicity

Valid experimental data to assess repeated toxicity of TEA, the degradation product of the target substance, were available for oral pathway (US EPA, 1986). Four groups of male and female Sprague-Dawley rats (30/sex/group) were administered daily 0, 30, 125 or 500 mg/kg bw/day for either 6 or 13 weeks. CNS effects seen as transient clinical signs (ataxia and hypoactivity) were found at the 500 mg/kg bw/day animals. These effects lasted less than 1 hour and are typical effects of alcohols. The NOAEL in this study was 125 mg/kg/day and the LOAEL was 500 mg/kg/day. No treatment related signs were observed in the 30 mg/kg/day or 125 mg/kg/day treatment groups.

Repeated inhalation toxicity

There are no studies available for titanium 2,2',2''-nitrilotrisethanolate itself. Since the substance hydrolyses ( half-life < 12 hours) read-across data from triethanolamine and titanium dioxide (TiO2) are used to evaluate the potential repeated dose toxicity caused by the target substance.

Repeated inhalation toxicity was investigated in a sub-acute 28 -day study performed according to OECD TG 41 and under GLP conditions, in which Wistar rats (10/sex/dose) were exposed head/nose only to 0, 0.02, 0.1 or 0.5 mg/L TEA for 6 hours/day and 5 days/week. No mortality was observed. No statistically significant differences between groups were observed in body weight, haematology and clinical chemistry. Differences in grip strength were judged not substance-related because of a lack of concentration- or time-related effect. No other abnormalities were observed during neurofunctional testing. A significant difference in red blood cells was observed in males of the mid-dose group compared to controls, but since this deviation was marginal, not observed in females, and not dose-related, this finding was considered of no toxicological significance. Local effects were characterized histopathologically by focal inflammatory changes in the submucosa of the larynx, with a concentration-dependent tendency in incidence and severity. No such effects were observed in females of the low dose, whereas minimal to slight effects were seen in males at this dose. Therefore, 0.02 mg/L was considered to be the NOAEC for local effects in females and the LOAEC for males. Since no systemic effects were observed, the systemic NOAEC was established to be 0.5 mg/L, the highest dose tested.

Hydrated titanium dioxide is a solid insoluble precipitate. Therefore, inhalation is unlikely route of human exposure of this decomposition product and TiO2 is not further considered in CSA.

Based on above information, titanium tetrabutanolate is regarded not to cause any inhalation hazard.

Repeated dermal toxicity

There are no studies available for titanium 2,2',2''-nitrilotrisethanolate itself. Since the substance hydrolyses (half-life < 12 hours) read-across data from triethanolamine (TEA) and titanium dioxide (TiO₂) are used to evaluate the potential repeated dose toxicity caused by the target substance.

In a sub-chronic dermal toxicity study in rats (20 animals/sex/dose) was conducted for TEA (Substance Evaluation Report, UK REACH CA, 2015). The LOAEL (local effects) was established to be 250 mg/kg bw/day, based on skin lesions. The LOAEL (systemic effects) was established to be 2000 mg/kg bw/day based on the magnitude of the kidney weight changes at the top dose, noting the absence of any histopathological findings associated with these changes at any dose level.

TiO2 has no adsorption potential through skin (US EPA, 1994; WHO, 1982).

Dermal route is not considered to be a relevant exposure route for humans since skin contact in use and production of the target substance is not likely and adequate RMMs are in use (see sections 9&10 of CSR).

Justification for classification or non-classification

The intrinsic properties of titanium 2,2',2''-nitrilotrisethanolate are related to the most hazardous degradation product; trisethanolamine (TEA). Based on the observations made after the subacute study in rats via inhalation there is no need for classification of the target substance in accordance with the criteria of CLP Regulation 1272/2008.