Trifluoroacetic acid

Endpoint summary

Description of key information

Since the substance to be tested is a corrosive liquid, testing was performed by the oral route with the neutralized form of the test substance. A sub-chronic toxicity study by dietary adminstration with the neutral salt sodium trifluoroacetate was identified and is considered appropriate to fulfil this information requirement. A NOAEL of 8.4 and 10.1 mg TFA/kg bw per day in male and female rats, respectively, was established after 90-day oral exposure. The lowest NOAEL of 8.4 mg TFA/kg bw per day was taken forward for risk assesment and DNEL derivation. More information about the read-across justification is included in the Reporting format as attached to the respective IUCLID entry (section 13).

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 04 Apr 2006 to 16 Feb 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

A sub-chronic toxicity study by dietary adminstration with the neutral salt sodium trifluoroacetate was identified and is considered appropriate to fulfil this information requirement. The results obtained on TFANa are expressed in mg of TFA moiety. More information about the read-across justification is included in the Reporting format as attached to the respective IUCLID entry (section 13).

Qualifier:

according to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Qualifier:

according to guideline

Guideline:

EU Method B.26 (Sub-Chronic Oral Toxicity Test: Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.3100 (90-Day Oral Toxicity in Rodents)

Qualifier:

according to guideline

Guideline:

other: M.A.F.F. in Japan 12 Nousan N°8147 (November, 2000)

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Specific details on test material used for the study:

Trifluoroacetic acid (TFA) is a corrosive liquid. To identify the systemic hazard of the substance, testing with the neutral salt sodium trifluoroacetate was considered appropriate to avoid local irritative effects at the site of administration. The results obtained on TFANa are expressed in mg of TFA moiety. The conversion factor from TFA-sodium salt to TFA is 0.84.

Species:

rat

Strain:

Wistar

Details on species / strain selection:

Wistar Rj:WI (IOPS HAN)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: R. Janvier, Le Genest St Isle, France
- Age at study initiation: 7 weeks
- Weight at study initiation: 225 to 259 g (males) and 165 to 200 g (females)
- Fasting period before study: no
- Assigned to test groups randomly: yes
- Housing: Rats were housed individually in suspended, stainless steel, wire-mesh cages.
- Diet: ad libitum, certified rodent powdered and irradiated diet A04CP1-10 (Scientific Animal Food and Engineering, Augy, France)
- Water: ad libitum, filtered and softened water from the municipal water supply
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 40-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12 (7 am - 7pm)

IN-LIFE DATES: From: April 12, 2006 (animal arrival) To:July 28, 2006 (final sacrifice)

Route of administration:

oral: feed

Details on route of administration:

The test substance was incorporated into the diet by dry mixing to provide the required concentrations.

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): The test substance formulations were prepared approximately every four weeks. There were three preparations in total.
- Mixing appropriate amounts with (Type of food): The test substance was incorporated into the diet (Certified rodent powdered and irradiated diet A04CP1-10 from S.A.F.E Augy, France) by dry mixing to provide the required concentrations.
- Storage temperature of food: Each test diet formulation was stored at room temperature and issued to the animal unit in polyethylene containers.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The homogeneity of the test substance in diet was verified on the first and third preparation at the lowest and highest concentrations. The dietary levels of the test substance were verified for each concentration on the first and third preparation. The stability of the test substance in the diet has been demonstrated in a previous study (SA 05054) at concentrations of 100 and 20000 ppm. At these dose levels, the diet preparations were found to be stable over 71 days at room temperature or over 71 days under frozen storage.
The accuracy and homogeneity of preparation was considered acceptable if the mean measured concentrations were 85-115% of the nominal concentration. Analysis was based on the analytical method validated for the test item based on LC-MS method.

Duration of treatment / exposure:

90 days

Frequency of treatment:

Continuously via dietary administration

Dose / conc.:

160 ppm

Dose / conc.:

1 600 ppm

Dose / conc.:

16 000 ppm

No. of animals per sex per dose:

10 male/10 female

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: based on the results of a preliminary 14-day rat toxicity study and a preliminary 28-day rat toxicity study in which 16000 ppm was considered to be a No Observed Adverse Effect Level (NOAEL), on the basis of higher plasma alanine aminotransferase activity, lower total cholesterol and glucose concentrations, higher urinary ketone levels, and higher mean absolute and relative liver weights in both sexes, and in the absence of associated histopathological findings.
- Rationale for animal assignment: By computer-generated random algorithm according to body weight, with all animals within ± 20% of the sex mean.
- Rationale for selecting satellite groups: Not applicable since no recovery groups were included.
- Post-exposure recovery period in satellite groups: Not applicable since no recovery groups were included.
- Section schedule rationale: On study Days 93, 94 or 95 of the dosing phase, all surviving animals from all groups were sacrificed by exsanguination under deep anesthesia (inhalation of Isoflurane). An approximately equal number of animals randomly distributed amongst all groups were sampled on each day. Animals were diet fasted overnight prior to sacrifice.

Positive control:

Not used

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: At least twice daily for mortality/viability (once daily on weekends or public holidays).

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Observed clinical signs were recorded at least once daily for all animals during the study. Detailed physical examinations were performed during the acclimatization phase and at least weekly during the treatment periods. The nature, pnset, severity, reversibility and duration of clinical signs were recorded. Cages and cage-trays were inspected daily for evidence of ill-health such as blood or loose feces.

BODY WEIGHT: Yes
- Time schedule for examinations: Each animal was weighed three times during the acclimatization period, on the first day of test substance administration, then at least weekly throughout the treatment period. Additionally, diet fasted animals were weighed before necropsy.

FOOD CONSUMPTION: yes
- Time schedule for examinations: The weight of food supplied and of that remaining at the end of the food consumption period was recorded weekly for all animals during the treatment period. From these records the mean daily consumption was calculated. Food spillage was also noted.

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: During the acclimatization period, all animals were subjected to an ophthalmic examination. After instillation of an atropinic agent (Mydriaticum, Merck Sharp and Dohme) each eye was examined by means of an indirect ophthalmoscope. During Week 14 of the treatment period, all surviving animals from all groups were re-examined.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the end of treatment
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes, overnight
- How many animals: all surviving animals
- The following parameters were examined: Red blood cell count (1), hemoglobin concentration (2), hematocrit (3), mean corpuscular volume (4), mean corpuscular hemoglobin (5), mean corpuscular hemoglobin concentration (6), reticulocyte count (7), white blood cell count and differential count evaluation (8) and platelet count (9) were assayed using a Advia 120 (Bayer Diagnostics, Puteaux, France). A blood smear was prepared and stained with Wright stain. It was examined when the results of
Advia 120 determinations were abnormal. Prothrombin time (10) was assayed on an ACL 3000 (Instrumentation Laboratory, Paris, France).

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the end of treatment
- Animals fasted: yes, overnight
- How many animals: all surviving animals
- The following parameters were examined: Total bilirubin (11), glucose (12), urea (13), creatinine (14), total cholesterol (17), triglycerides (18), chloride (23), sodium (23), potassium (23), calcium (24) and inorganic phosphorus (25)
concentrations, and aspartate aminotransferase (19), alanine aminotransferase (20), alkaline phosphatase (21) and gamma-glutamyltransferase (22) activities were assayed on plasma samples, total protein (15) and albumin (16) concentrations were assayed on serum samples using an Advia 1650 (Bayer Diagnostics, Puteaux, France). Globulin concentrations and albumin/globulin ratio values were calculated.

URINALYSIS: Yes
- Time schedule for collection of urine: on study Days 87 or 88 in the morning, overnight urine samples were collected.
- Metabolism cages used for collection of urine: Not specified
- Animals fasted: Yes
- How many animals: all surviving animals
- The following parameters were examined: general appearance, volume, pH, urinary refractive index. Glucose, bilirubin, ketone bodies, occult blood, protein and urobilinogen were assayed using a Clinitek 200+ and Multistix dipsticks (Bayer Diagnostics, Puteaux, France). Microscopic examination of the urinary sediment was performed after centrifugation of the urine. The presence of red blood cells, white blood cells, epithelial cells, bacteria, casts and crystals was graded.

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: week 11-12 of treatment
- Dose groups that were examined: all surviving animals
- Battery of functions tested: Motor activity (recording period 90 minutes with data being collected at 15-minute intervals), sensory reactivity (pupillary reflex, surface righting reflex, corneal reflex, flexor reflex, auditory startle response, tail pinch response), Open field observation (changes in gait, posture, as well as presence of clonic or tonic movements, stereotypic behaviour, bizarre behaviour e.g. self-mutilation, walking backward), grip strength (fore- and hind-limb, recorded as mean of three measurements per animal) .

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
The following organ weights and terminal body weight were recorded from all animals on the scheduled day of necropsy:
Adrenal gland, brain, epididymis, heart, kidney, liver, ovary, pituitary gland, prostate gland, spleen, testis, thymus, thyroid gland (with parathyroid gland) and uterus (including cervix). Paired organs were weighed together.

HISTOPATHOLOGY: Yes. The samples of following tissues and organs were collected:
Adrenal gland
Aorta
Articular surface (femoro-tibial joint)
Bone (sternum)
Bone marrow (sternum)
Brain
Epididymis
Esophagus
Exorbital (lachrymal) gland
Eye and optic nerve
Harderian gland
Heart
Intestine (duodenum, jejunum, ileum,
cecum, colon, rectum)
Kidney
Larynx/Pharynx
Liver
Lung
Lymph nodes (submaxillary, mesenteric)
Mammary gland
Nasal cavities
Ovary
Pancreas
Pituitary gland
Prostate gland
Sciatic nerve
Seminal vesicle
Skeletal muscle
Skin
Spinal cord (cervical, thoracic, lumbar)
Spleen
Stomach
Submaxillary (salivary) gland
Testis
Thymus
Thyroid gland (with parathyroid gland)
Tongue
Trachea
Urinary bladder
Uterus (including cervix)
Vagina

All of the above mentioned samples (except exorbital lachrymal gland, larynx/pharynx and nasal cavities) were embedded in paraffin wax. Histological sections, stained with hematoxylin and eosin, were prepared from all organs and tissue samples from all the animals in the control and high dose groups, and from the animal (QT3M0972) found dead on Day 15.
Additionally, sections from liver, kidney, lung, thyroid gland, from potential target organs (heart) and from significant gross findings observed at necropsy were prepared for all the animals in all intermediate dose groups.

Statistics:

The Bartlett test will be performed to compare the homogeneity of group variances.
- If the Bartlett test is not significant (p>0.05), means will be compared using the analysis of variance (ANOVA). If the ANOVA is not significant (p>0.05), the group means are considered to be homogeneous and no further analysis will be performed. If the ANOVA is significant (p<0.05), means of the exposed groups will be compared to the mean of the control group using the Dunnett test (2-sided).
- If the Bartlett test is significant (p<0.05), data will be transformed using the log transformation. If the Bartlett test on log transformed data is not significant (p>0.05), means will be compared using the ANOVA on log transformed data. If the ANOVA on log
transformed data is not significant (p>0.05), the group means are considered to be homogeneous and no further analysis will be performed. If the ANOVA on log transformed data is significant (p<0.05), means of the exposed groups will be compared to the mean of the control group using the Dunnett test (2-sided) on log transformed data.
- If the Bartlett test is significant (p<0.05) even after log transformation, group means will be compared using the non-parametric Kruskal-Wallis test. If the Kruskal-Wallis test is not significant (p>0.05), the group means are considered to be homogeneous and no further analysis will be performed. If the Kruskal-Wallis test is significant (p<0.05), means of the exposed groups will be compared to the mean of the control group using the Dunn test (2-sided).

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

One male from the 16000 ppm group was noted to have ocular discharge in both eyes from study Days 78 to 85. As this sign was transient and disappeared before the end of the study, it was considered not to be treatment-related.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

One male from the 1600 ppm group was found dead on study Day 15. At necropsy, this animal was noted to have torsion of the intestine and a dark content within the ileum and jejunum. This intestinal torsion was considered to be the cause of death and not to be treatment related. All other macroscopic findings were related to agonal changes observed at the histopathology examination. In addition, at the histopathological examination, degenerative cardiomyopathy was noted. This change is a common finding observed spontaneously in the Wistar rat strain of this age and was considered not to be treatment-related

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

At 16000 ppm, mean body weight of males was reduced by 5 to 11% from study Day 15 onwards, resulting in an overall reduction in mean body weight gain of 17% on Day 92, when compared to controls. The effect was statistically significant at most time points (p<0.01 or 0.05). In females, mean body weight was reduced by up to 6% during the course of the study, resulting in an overall reduction in mean body weight gain of 14% on Day 92, when compared to controls. The
effect was statistically significant on a number of occasions for cumulative body weight gain (p<0.01 or 0.05). Body weight parameters were not affected in either sex at 1600 ppm and at 160 ppm.
Results for mean body weight, mean body weight gain and mean absolute body weight gain are given in Tables 1, 2 and 3 of the attached document.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Up to the highest dose level tested food consumption was not affected in either sex.

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

effects observed, non-treatment-related

Description (incidence and severity):

There was no evidence of treatment-related effects up to the highest dose level tested of 16000 ppm.
One male from the 16000 ppm group had a corneal opacity in the left eye and another male had anterior synechia in the iris of the left eye.

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

When compared to the controls, lower mean hemoglobin concentration (-8%, p<0.01) was noted at 16000 ppm in females only. This slight change was associated with lower mean corpuscular volume (-6%, p<0.01), mean corpuscular hemoglobin (-7%, p<0.01) and hematocrit (-6%, p<0.01). At 1600 ppm, lower mean hemoglobin concentration (-4%, p<0.05), essentially due to low values noted in two animals, and lower mean corpuscular hemoglobin (-3%, p<0.01) were also noted (see also Table 4 of the attached document). No treatment-related change was noted in males at any dose level and in females at 160 ppm.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

Treatment-related changes were observed at 16000 and 1600 ppm in both sexes. Mean total bilirubin and glucose concentrations were lower in both sexes and mean alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase activities were higher in males only (see also Table 5 of the attached document). The slightly lower mean total bilirubin concentration noted at 160 ppm in both sexes was considered not to be treatment-related as the difference to controls was not statistically significant and all individual values were within the in-house historical control data.

Urinalysis findings:

effects observed, treatment-related

Description (incidence and severity):

When compared to the control groups, higher ketone levels were noted at 16000 and 1600 ppm in both sexes. No other treatment-related change was noted for the parameters assayed. The few other statistically significant differences were considered to be incidental.

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

Locomotor activity
At 16000, 1600 and 160 ppm in both sexes, overall mean exploratory locomotor activity was comparable to control values. In addition, the pattern of the locomotor activity over time was similar to controls.

Open field observation
No treatment-related changes were recorded during the open field observation at any dose level in either sex. The few changes noted were observed in isolation and/or with no dose-relationship and were considered not to be treatment-related

Sensory reactivity
All reflexes and responses evaluated were unaffected by the treatment at any dose level in either sex. The increased incidence of exaggerated flexor reflex for both hind paws observed in the high dose females was considered not to be treatment-related, due to the limited magnitude of the change and inter-individual variation of this parameter.

Grip strength
The fore- and hind-limb grip strength were unaffected by treatment at any dose level in either sex. A slight decrease in forelimb grip strength was observed in high dose females in comparison to controls (-17%, p≤0.01), but it was considered to be fortuitous and due to a particularly high mean value in the control group. Furthermore, the mean value observed in the high dose females for this parameter was within the in-house historical control range

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Mean absolute and relative liver weight were statistically significantly higher in male and female rats at 16000 and 1600 ppm when compared to controls (see Table 6 of the attached document). These changes were dose- and treatment-related and associated with hepatocellular hypertrophy. All other statistically significant organ weight differences were judged to be incidental in view of their individual variation and in the absence of any correlated histopathological finding.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

With the exception of the higher incidence of foci (red or white) within the liver observed in males at 16000 ppm, all the other changes were considered to be incidental and not treatment-related.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Treatment-related histopathological changes were observed in the liver (see Table 7 of the attached document). In all male and most females at 16000 ppm, as well as in a proportion of males at 1600 ppm, a minimal to moderate diffuse centrilobular to panlobular hepatocellular hypertrophy with groundglass appearance of the hepatocellular cytoplasm was observed. This latter observation is usually induced by peroxisome proliferators. This change was associated with a loss of the periportal hepatocellular vacuolation observed at 16000 ppm in both sexes and at 1600 ppm in males. The effect was dose-related and correlated with the higher mean liver weight noted in these groups. There was also a higher incidence of hepatocellular necrotic foci in males at 16000 ppm when compared to controls, which was considered to be adverse. This finding was correlated with higher individual values of aspartate aminotransferase and alanine aminotransferase activities observed in clinical chemistry evaluation.
A higher incidence of minimal to slight degenerative cardiomyopathy was noted in males at 16000 ppm. As this change is a common spontaneous finding observed in the Wistar rat of this strain and age, including in untreated control animals, with a similar severity and incidence, it was considered not to be treatment-related
No effect of treatment was seen in any other organ examined microscopically. Some other histopathological findings were noted in animals of all groups but they were considered to be incidental, as they were within the range of expected changes for rats of this age and strain kept under laboratory conditions.

Histopathological findings: neoplastic:

no effects observed

Other effects:

not specified

Dose descriptor:

NOAEL

Effect level:

160 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

clinical biochemistry

haematology

organ weights and organ / body weight ratios

Critical effects observed:

not specified

Homogeneity and concentration checks of TFA in the diet were within 86 to 108% of the nominal concentration, with the exception of only one analysis out of eight at 16000 ppm (129%) which was outside the in-house target range of 85 to 115% of the nominal concentration. In isolation, this result was considered acceptable for the study. Therefore homogeneity and concentration checks of TFA at 16000 ppm were considered to be acceptable. At 1600 and 160 ppm, concentrations and/or homogeneity were within the in-house target range and were therefore considered to be acceptable.

The mean achieved dosage intake of TFA per group was as follows:

Mean achieved dietary intake of Sodium trifluoroacetate (TFA) Weeks 1-13
Diet concentration ppm	Males (mg/kg/day)	Females (mg/kg/day)
160	10 (8.4)	12 (10.1)
1600	98 (82.3)	123 (103.3)
16000	1040 (876)	1216 (1021)

 *Between brackets the corresponding TFA levels are indicated.

Conclusions:

In the 90-day oral study with Wistar rats, the test substance sodium trifluoroacetate was administered to male and female rats at 160, 1600 and 16000 ppm via dietary administration. Based on the observed effects (increase in liver weight, histopathological changes in the liver and changes in haematological parameters, clinical biochemistry and urinalysis), the NOAEL was set at 160 ppm.

Executive summary:

In a GLP-compliant OECD Guideline 408 study, the test substance sodium trifluoroacetate was administered continuously via dietary administration to separate groups of Wistar rats (10/sex/group) at concentrations of 160, 1600 and 16000 ppm (equating approximately to 8.4, 82.3, 876 mg TFA/kg body weight/day in males and 10.1, 103.3, 1021 mg TFA/kg body weight/day in females), respectively for at least 90 days. A similarly constituted group of 10 males and 10 females received untreated diet and acted as a control. No toxicologically significant changes were noted in clinical appearance, functional observations, food consumption and ophthalmoscopy. At necropsy a reduction in mean body weight gain of 17% and 6% was observed for males and females, respectively at 16000 ppm when compared to the controls. Body weight parameters were not affected in either sex at 1600 ppm and at 160 ppm.

Clinical pathology determinations revealed lower mean hemoglobin concentration in females. This slight change was associated with a statistically significantly lower mean corpuscular volume, mean corpuscular hemoglobin and hematocrit. In addition, mean total bilirubin and glucose concentrations were markedly lower in both sexes. Mean values for alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase activities were higher in males. At urinalysis, higher ketone levels were noted in both sexes.

Microscopic examination revealed test item related changes in the liver. In all males and most females at 16000 ppm, as well as in a proportion of males at 1600 ppm, a minimal to moderate diffuse centrilobular to panlobular hepatocellular hypertrophy with groundglass appearance of the hepatocellular cytoplasm was observed. This change was associated with a loss of the periportal hepatocellular vacuolation observed at 16000 ppm in both sexes and at 1600 ppm in males. The effect was dose-related and correlated with the higher mean liver weight noted in these groups (up to +33% and +28% relative to vehicle controls in males and females, respectively at the highest dose level). There was also a higher incidence of hepatocellular necrotic foci in males at 16000 ppm when compared to controls, which was considered to be adverse.This finding was correlated with higher individual values of aspartate aminotransferase and alanine aminotransferase activities observed in clinical chemistry evaluation.

The dose level of 160 ppm of sodium trifluoroacetate is considered to be a No Observed Adverse Effect Level (NOAEL) in both sexes (equating approximately to 8.4 mg TFA/kg body weight/day in males and 10.1 mg TFA/kg body weight/day in females).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

8.4 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

GLP-compliant guideline study, klimisch 1

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A reliable 90 -day study with rats by oral route of administration is available. In this GLP-compliant OECD Guideline 408 study, the test substance sodium trifluoroacetate was administered continuously via dietary administration to separate groups of Wistar rats (10/sex/group) at concentrations of 160, 1600 and 16000 ppm (equating approximately to 9.9, 98, 1043 mg/kg body weight/day in males and 12.2, 123, 1216 mg/kg body weight/day in females), respectively for at least 90 days. A similarly constituted group of 10 males and 10 females received untreated diet and acted as a control.

No toxicologically significant changes were noted in clinical appearance, functional observations, food consumption and ophthalmoscopy. At necropsy a reduction in mean body weight gain of 17% and 6% was observed for males and females, respectively at 16000 ppm when compared to the controls. Body weight parameters were not affected in either sex at 1600 ppm and at 160 ppm.

Clinical pathology determinations revealed lower mean hemoglobin concentration in females. This slight change was associated with a statistically significantly lower mean corpuscular volume, mean corpuscular hemoglobin and hematocrit. In addition, mean total bilirubin and glucose concentrations were markedly lower in both sexes. Mean values for alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase activities were higher in males. At urinalysis, higher ketone levels were noted in both sexes.

Microscopic examination revealed test item related changes in the liver. In all males and most females at 16000 ppm, as well as in a proportion of males at 1600 ppm, a minimal to moderate diffuse centrilobular to panlobular hepatocellular hypertrophy with groundglass appearance of the hepatocellular cytoplasm was observed. This change was associated with a loss of the periportal hepatocellular vacuolation observed at 16000 ppm in both sexes and at 1600 ppm in males. The effect was dose-related and correlated with the higher mean liver weight noted in these groups (up to +33% and +28% relative to vehicle controls in males and females, respectively at the highest dose level). There was also a higher incidence of hepatocellular necrotic foci in males at 16000 ppm when compared to controls, which was considered to be adverse.This finding was correlated with higher individual values of aspartate aminotransferase and alanine aminotransferase activities observed in clinical chemistry evaluation.

The dose level of 160 ppm of sodium trifluoroacetate is considered to be a No Observed Adverse Effect Level (NOAEL) in both sexes (equating approximately to 8.4 mg TFA/kg body weight/day in males and 10.1 mg TFA/kg body weight/day in females).

In addition, a GLP-compliant OECD Guideline 452 study is available for sodium trifluoroacetate. The purpose of this study was to determine the potential toxicity of Sodium Trifluoroacetate (TFA), when administered by drinking water administration to Sprague-Dawley rats for 52 weeks and to assess the reversibility, persistence, or delayed occurrence of toxic effects following a 6-week recovery period. In adition, to determine systemic exposure, plasma concentrations of TFA were determined at each dosage level. Administration of Sodium Trifluoroacetate to Sprague Dawley rats via drinking water for 52 weeks at dosages of 30, 120 and 600 ppm followed by a 6-week recovery period did not result in any treatment-related adverse effects. Therefore the NOAEL for this study was considered to be 600 ppm (corresponding to 37.8 mg/kg/day in males and 64.0 mg/kg/day in females).

The lowest NOAEL from the 90 -day study shall be taken forward for risk assesment and DNEL derivation.

Justification for classification or non-classification

Based on the available repeated dose toxicity studies, the test substance does not meet the criteria of the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 and therefore no classification is needed.