Aluminium tributanolate

Endpoint summary

Description of key information

Upon contact with water or moisture (e.g. within mucous membranes) aluminium tributanolate hydrolyses immediately to butan-1ol and aluminium 3+ cations (as hydroxide and oxyhydroxide). Hence, toxicity is determined by the toxicity of these two species

Four groups of male and female CD rats (30/sex/group) were administered daily by gavage 0, 30, 125 or 500 mg butan-1-ol /kgbw/d for either 6 or 13 weeks.  No dose-related differences were observed between treatment or control rats in body or organ weight changes, food consumption or mortality, gross pathology, and histopathological and ophthalmic evaluations.  Ataxia and hypoactivity (lasting less than 1 h) were observed 2 to 3 minutes after dosing in both sexes of the high-dose group (500/mg/kgbw/d) during the final 6 weeks of dosing.  nBA was not expected to persist or accumulate over time.  No treatment-related signs were observed in the 30 or 125 mg/kgbw/d treatment groups, the latter value being the no-observed adverse effect level (EPA 1986).

Male Sprague-Dawley rats were exposed to aluminium hydroxide with diet at 302 mg Al/kg body weight for 28 days. During the entire experimental period, no mortality was reported and no treatment-related clinical signs were observed. There were no significant differences in body weight, food and water consumption and haematological parameters compared to controls that received basal diet. There were no other significant group differences in organ weights and microscopic changes. Aluminium concentrations in femur samples were <1 ppm (quantifiable in all 5 samples from animals treated with Al (OH)3 and in 2 samples from the control animals).The results of this study provide no evidence for significant deposition of Al in the bone and for toxicity of Al hydroxide during 28-day dietary administration at daily doses up to ≈300 mg Al/kg body weight. (Hicks 1987)

Sodium aluminium phosphate was administered to beagle dogs with diet at concentrations 0% (control), 0.3%, 1.0% and 3.0% for 6 months. There were no significant group differences in body weight throughout the experiment. Reductions in mean body weight occurred in all groups during week 27, which the authors attributed to “pre-termination tests and increased handling by technicians.” No treatment-related clinical signs and no ocular changes in any of the animals were observed. In most weeks, treated male and female dogs consumed less food than control dogs. In male animals, none of the differences in mean food consumption values were statistically significant. In females, significant reductions occurred “sporadically”. The authors did not consider these differences in food consumption as “toxicologically significant”, a conclusion that was supported by the absence of corresponding reduction in body weights. The treatment did not have any effect on haematological and blood biochemistry parameters, urinalysis results and results of analysis for occult blood in faeces. There were no significant differences in mean organ weights between the treated groups and the control group. Gross pathology and histopathology findings were in the “normal range of variations for dogs of this strain and age”; no treatment-related lesions were observed. The results of this study provide no evidence for toxicity of acidic form of sodium aluminium phosphate during 6-month administration at concentrations up to 3% in the diet (30 mg/kg bw as Al) (Katz 1984).

In a poorly documented study Aluminium (as Aluminium citrate) in drinking water was shown to affect erythropoiesis in rats with normal renal function (Vittori 1999).

Rats were exposed to vapours of n-butanol at concentrations of 50 and 100 ppm 6 h/day, 5 days/week for 3 months (154 and 308 mg/m3). No significant changes in body weight gain, in absolute and relative organ weights and clinical biochemistry parameters were observed. N-butanol caused significant disturbances of motor coordination disturbances at 100 ppm. Significant increase in sensitivity to pain in animals exposed to n-butyl alcohol was observed. N-Butyl alcohol provoked the increase of lipid peroxidation in hepatic microsomes without any induction of cytochrome P450 monooxygenases (Korsal 1994).

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

abstract

Remarks:

abstract from reliable source

Qualifier:

no guideline followed

GLP compliance:

not specified

Dose descriptor:

NOAEL

Effect level:

125 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: CNS effects

Critical effects observed:

yes

Lowest effective dose / conc.:

500 mg/kg bw/day (nominal)

System:

central nervous system

Organ:

not specified

Treatment related:

yes

Executive summary:

Four groups of male and female CD rats (30/sex/group) were administered daily (not further specified; 5 or 7 d/wk) by gavage 0, 30, 125 or 500 mg nBA/kgbw/d for either 6 or 13 weeks.  Body weight and food consumption were recorded weekly.  Any signs of mortality and overt toxicity were noted twice a day.  Ophthalmic examination was conducted prior to treatment and during week 13 before final necropsy.  Clinical pathology of urine and blood was investigated, prior to study initiation, in a separate group of 10 male and 10 female rats, during week 6 in all surviving rats scheduled for interim kill and during week 13 in the first 10 male and 10 female rats scheduled for final necropsy.  Ten male and ten female rats from each group were necropsied on study days 43 to 44 and the remaining animals on study days 92 to 93.  Gross pathology of all animals was assessed and organs from animals necropsied on study days 92 to 93 were weighed.  A complete histopathological investigation was made of all animals of the control and high-dose groups.  In the low and mid-dose groups, histopathology included the liver, kidney, and heart from all animals and all gross lesions.  All animals found dead or killed in extremis were also microscopically examined.  No dose-related differences were observed between treatment or control rats in body or organ weight changes, food consumption or mortality, gross pathology, and histopathological and ophthalmic evaluations.  Ataxia and hypoactivity (lasting less than 1 h) were observed 2 to 3 minutes after dosing in both sexes of the high-dose group (500/mg/kgbw/d) during the final 6 weeks of dosing.  Such ataxia and hypoactivity are typically seen following high oral doses of alcohols.  The rapid induction/remission of these effects and the reported increased incidence after the interim kill may be due to the fact that personnel were able to collect post-dose observations more quickly since fewer animals required dosing.  nBA was not expected to persist or accumulate over time.  No treatment-related signs were observed in the 30 or 125 mg/kgbw/d treatment groups, the latter value being the no-observed adverse effect level

Reference 2

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Deviations:

not applicable

Principles of method if other than guideline:

Male Sprague-Dawley rats were exposed to aluminium-compounds with diet. The animals were randomly assigned to five groups, 25 animals in each. The groups were receiving 1) basal diet (control), 2) aluminium hydroxide (302 mg Al/kg body weight/day), 3) KASAL -the basic form of sodium aluminium phosphate containing ≈6% of Al (141 mg Al/kg body weight/day), 4) KASAL II - the basic form of sodium aluminium phosphate containing ≈13% of Al (67 mg Al/kg body weight/day) and 5) KASAL II (288 mg Al/kg body weight/day). The treatment continued for 28 days, during which the animals were observed twice daily for their behaviour, signs of toxicity, and mortality. General physical examinations, body weight and food consumption measurements were performed weekly. After 28 days of treatment, 15 animals from each group were killed. Blood was collected from 5 rats of each group for blood cell counts, haemoglobin concentration, hematocrit and serum chemistry measurements. These rats were subjected to gross necropsy and histopathological examination. Femurs from 10 rats were taken for possible aluminium analysis; femurs from 5 rats were analyzed for Al concentrations. Five rats were allowed to recover for 2 months and five rats – for 5 months after termination of the treatment. During these recovery periods, the rats received the basal diet and were observed daily; body weight and food consumption were measured monthly. Femurs were collected at autopsy from these rats for aluminium analysis.

GLP compliance:

not specified

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male

Details on test animals or test system and environmental conditions:

- Supplier: Charles River Breeding Laboratories, Inc.
- Number of Animals in the Study: 125
- Age at Initiation of Treatment: 48 days.
- Weight: no information
- Acclimation: 3 weeks
The animals were individually identified.

Environmental conditions
The animal room environment was maintained with the following conditions:
- Temperature: 19-24 °C;
- Relative Humidity: 40-60%;
There is no information on light/dark cycle

Dust concentration in the air of the animal room was <0.02 µg/L.

Housing & Caging
The animals were housed individually in 22.5 x 20 x 17.5 stainless steel wire-mesh cages on racks

Diet and Water
The basal diet was Purina Certified Rodent Chow no. 5002 (Ralston Purina, St Lois, MO). Aluminium concentration in the basal diet was 66 ppm. The animals had free access to water. Aluminium was detected and quantified in one of four samples of the water ( 0.017 ppm)

The contribution of Al from the room air and drinking water was estimated as <20 µg/rat during the 28 days of treatment.

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
The basal diet was blended with the appropriate amount of the test chemical and a small amount (0.5% wt) of Mazola corn oil “to suppress dust”.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Test material concentrations “in each of the blended diets” were verified by atomic absorption spectrometry analysis. The actual concentrations were within 5% of the nominal concentrations.

Duration of treatment / exposure:

28 days

Frequency of treatment:

Daily, 7 days per week.

Dose / conc.:

14 470 ppm

Remarks:

Measured concentrations:
Al(OH)3: 302 mg Al/kg bw;
Basis:
nominal in diet

No. of animals per sex per dose:

25

Control animals:

yes, plain diet

Details on study design:

After 28 days of treatment, 15 animals from each group were killed. Blood was collected from 5 rats of each group for blood cell counts, haemoglobin concentration, hematocrit and serum chemistry measurements. These rats were subjected to gross necropsy and histopathological examination. Femurs from 10 rats were taken for possible aluminium analysis; femurs from 5 rats were analyzed for Al concentrations. Five rats were allowed to recover for 2 months and five rats – for 5 months after termination of the treatment. They were fed the basal diet during the recovery periods.

Positive control:

No data.

Observations and examinations performed and frequency:

Observations and clinical examination:
- Morbidity, signs of toxicity and mortality: twice daily
- “General physical examination”: weekly
- Food consumption: weekly for 10 animals per group
- Body weights: weekly for 10 animals per group
- Water consumption: weekly for 5 animals per group

Haematology:
Blood was collected from the abdominal aorta of 5 rats in each group at sacrifice after 28 days of treatment. Hematocrit, haemoglobin concentration, red blood cell count, white blood cell count (total and differential) and platelet count were determined.

Blood chemistry:
Blood was collected from the abdominal aorta of 5 rats in each group at sacrifice after 28 days of treatment. Alanine aminotransferase, alkaline phosphatase, blood urea nitrogen, creatinine, phosphorus, sodium, chloride and potassium were analysed in serum.

Sacrifice and pathology:

Animals sacrificed after 28 days of treatment

Fifteen rats from each group were killed after 28 days of treatment.
Five rats were subjected to gross necropsy and histopathological examination. The brain, liver, kidneys and testes were weighted. Tissues of the heart, liver, kidney and testes were fixed in 10% neutral buffered formalin or 2.5 buffered glutaraldehyde and processed for subsequent light microscopic examination.
Femur was collected from 10 rats in each group for Al analysis; the femur of 5 rats per group was analyzed for Al concentration

Animals sacrificed after recovery periods
Five animals were killed 2 months and five animals- 5 months after termination of the treatment. Femurs were collected at autopsy for analysis of aluminium. Autopsy examination and histopathology were not performed on these animals.

Other examinations:

Bone aluminium analysis
Analyses were performed using a Perkin-Elmer 5000 (Norwalk, CT) atomic absorption spectrophotometer with a graphite furnace and Zeeman background correction system. Procedural blanks were used to correct for background Al levels and to estimate limits of detection and quantification as suggested by the American Chemical Society Committee on Environmental Improvement (1980). Values between the limit of detection and the limit of quantification could not be determined precisely and were reported as a range. Numerical values were assigned only to measurements exceeding the limit of quantification.

Measures to minimize contamination of samples by Al
Bone specimens were collected in a clean room. Personnel took shower before entering the room and wore Al-free disposable cloths. Autopsy instruments were washed with 20% nitric acid between autopsies and rinsed with distilled-deionised water. All tissues were collected in acid-washed polypropylene tubes.
Rinses of autopsy instruments and surfaces were analyzed and found to be free of Al.

Statistics:

Mean values (body and organ weights, food consumption, hematology and biochemistry parameters) from the treatment groups were compared with those from the control group using Dunnett’s Test (Dunnett, 1964. Biometrics, 22:482). Non-parametrical comparison of treated and control values was conducted using the Mann-Whitney U-test (Sokal and Rohlf, 1969). Frequencies were compared using Mantel-Haenzel trend analysis (Mantel, 1963. J. Am. Statist. Ass. 58:690) and Chi-square analysis (Sokal and Rohlf, 1969) or Fisher Exact test (Ingelfinger et al, 1983).

Clinical signs:

no effects observed

Description (incidence and severity):

Observations included abrasions, scabs, sporadic cases of chromorhinorrhoea, chromodacryorrhoea, hair loss and dehydration. All the observations were characteristic of the Sprague-Dawley rats; no unusual findings were noted.

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Description (incidence and severity):

No significant group differences throughout the treatment and recovery periods.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

No significant group differences throughout the treatment and recovery periods.

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

All haematological indices in the treated groups were similar to those in the control group.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

No “toxicologically significant” differences between the treated groups and the control group were observed. A mild (2-4%) but significant increase in serum sodium level was observed in all treated group compared to the control group. However, all the increased sodium levels were within the range of historical control for rats of the same age in the laboratory.

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

A significant 16% increase in absolute kidney weight was observed in the group of rats receiving KASAL II at the dose of 67 mg Al/kg b.w. This increase appeared to be not treatment-related because no such increase was seen in the group of animals treated with KASAL II at the dose of 288 mg Al/kg b.w. There were no other significant group differences in organ weights.

Gross pathological findings:

not specified

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

All lesions seen at microscopic examination were “those normally expected for young adult male Sprague-Dawley rats.” No lesions suggestive of a treatment-related effect were seen.

Histopathological findings: neoplastic:

no effects observed

Details on results:

Mortality:
No mortality was reported.

Body weight:
No significant group differences throughout the treatment and recovery periods.

Clinical Observations:
Observations included abrasions, scabs, sporadic cases of chromorhinorrhoea, chromodacryorrhoea, hair loss and dehydration. All the observations were characteristic of the Sprague-Dawley rats; no unusual findings were noted.

Food and Water Consumption:
No significant group differences throughout the treatment and recovery periods.

Haematology:
All haematological indices in the treated groups were similar to those in the control group.

Clinical Chemistry:
No “toxicologically significant” differences between the treated groups and the control group were observed. A mild (2-4%) but significant increase in serum sodium level was observed in all treated group compared to the control group. However, all the increased sodium levels were within the range of historical control for rats of the same age in the laboratory.

Organ Weight:
A significant 16% increase in absolute kidney weight was observed in the group of rats receiving KASAL II at the dose of 67 mg Al/kg b.w. This increase appeared to be not treatment-related because no such increase was seen in the group of animals treated with KASAL II at the dose of 288 mg Al/kg b.w. There were no other significant group differences in organ weights.

Histology:
All lesions seen at microscopic examination were “those normally expected for young adult male Sprague-Dawley rats.” No lesions suggestive of a treatment-related effect were seen.

Dose descriptor:

NOAEL

Effect level:

302 mg/kg diet

Based on:

test mat.

Sex:

male

Basis for effect level:

other: absence of effects

Critical effects observed:

not specified

Tissue Metal Levels:

Aluminium levels in the femur

All the concentrations were <1 ppm and most were below the limit of detection or quantification. The distribution of samples in which Al was not detectable, was detectable but not quantifiable or was quantifiable was similar in all the groups (the comparison using Chi-square analysis). It should be noted that this comparison was based on small numbers of samples from each group (5). Al was quantifiable in all 5 samples from animals treated with Al (OH)₃ and in 2 samples from the control animals.

Conclusions:

The results of this study provide no evidence for significant deposition of Al in the bone and for toxicity of Al hydroxide during 28-day dietary administration at daily doses up to ≈300 mg Al/kg body weight.

Executive summary:

Male Sprague-Dawley rats were exposed to aluminium-compounds with diet. The animals were randomly assigned to five groups, 25 animals in each. The groups were receiving 1) basal diet (control), 2) aluminium hydroxide (302 mg Al/kg body weight), 3) KASAL -the basic form of sodium aluminium phosphate containing ≈6% of Al (141 mg Al/kg body weight), 4) KASAL II - the basic form of sodium aluminium phosphate containing ≈13% of Al (67 mg Al/kg body weight) and 5) KASAL II (288 mg Al/kg body weight). The treatment continued for 28 days, during which the animals were observed twice daily for their behaviour, signs of toxicity, and mortality. General physical examinations, body weight and food consumption measurements were performed weekly. After 28 days of treatment, 15 animals from each group were killed. Blood was collected from 5 rats of each group for blood cell counts, haemoglobin concentration, hematocrit and serum chemistry measurements. These rats were subjected to gross necropsy and histopathological examination. Femurs from 10 rats were taken for possible aluminium analysis; femurs from 5 rats were analyzed for Al concentrations. Five rats were allowed to recover for 2 months and five rats – for 5 months after termination of the treatment. During these recovery periods, the rats received the basal diet and were observed daily; body weight and food consumption were measured monthly. Femurs were collected at autopsy from these rats for aluminium analysis. During the entire experimental period, no mortality was reported and no treatment-related clinical signs were observed. All clinical observations were characteristic of male Sprague-Dawley rats of relevant age. There were no significant group differences in body weight, food and water consumption and haematological parameters. A mild (2-4%) but significant increase in serum sodium level was observed in all treated group compared to the control group. However, all the increased sodium levels were within the range of historical control for rats of the same age in the laboratory. A significant 16% increase in absolute kidney weight was reported in the group of rats receiving KASAL II at 67 mg Al/kg b.w. This increase appeared to be not treatment-related because no such increase was seen in the group of animals treated with this substance at 288 mg Al/kg b.w. There were no other significant group differences in organ weights. All lesions seen at microscopic examination were “those normally expected for young adult male Sprague-Dawley rats.” No lesions suggestive of a treatment-related effect were seen. Aluminiumconcentrations in all femur samples from all groups were <1 ppm and most were below the limit of detection or quantification. The distribution of samples in which Al was not detectable, was detectable but not quantifiable or was quantifiable, was similar in all the groups. It should be noted that this comparison was based on small numbers of samples from each group (5). Al was quantifiable in all 5 samples from animals treated with Al (OH)₃, in 2 samples from the control animals and in none of the samples from animals treated with KASAL or KASAL II.The results of this study provide no evidence for significant deposition of Al in the bone and for toxicity of Al hydroxide or basic food grade sodium aluminium phosphate (KASAL and KASAL II) during 28-day dietary administration at daily doses up to ≈300 mg Al/kg body weight. 

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

125 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

For the other hydrolysis product aluminium 3+ species a NOAEL of 300 mg/kg bw was derived in a subacute study in rats with Al(OH)3

System:

other: no treatment related effects for both aluminium and butan-1-ol

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Version / remarks:

3 month toxicity study studying a limited number of endpoints

Principles of method if other than guideline:

In this study only a limited number of endpoints was included (see below)

GLP compliance:

not specified

Species:

rat

Strain:

Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Imp: DAK stock
- Age at study initiation:no data
- Weight at study initiation:322-329 g
- Housing: no data
- Diet/water: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C):no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE: no data (generated by heating liquid solvents in washers)

CHAMBER DESCRIPTION
- Exposure apparatus: dynamic inhalation chamber (1.3 m 3 volume).
- Method of holding animals in test chamber: no data

TEST ATMOSPHERE
- Brief description of analytical method used: GC with FID with 1.5 m metal column with 10% QV-17 on chromasorb W H P (80—100 mesh) as a stationary phase at column temperature of 100°C.
- Samples taken from breathing zone: no data (samples taken every 30 min)

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

GC with FID with 1.5 m metal column with 10% QV-17 on chromasorb W H P (80—100 mesh) as a stationary phase at column temperature of 100°C.

Duration of treatment / exposure:

3 months

Frequency of treatment:

6 hours/day, 5 days/week for 3 months.

Dose / conc.:

154 mg/m³ air

Dose / conc.:

308 mg/m³ air

No. of animals per sex per dose:

12/concentration (24 for controls)

Control animals:

yes, sham-exposed

Observations and examinations performed and frequency:

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

HAEMATOLOGY: Yes
- Time schedule for collection of blood: before exposure and 1 week before termination
- Anaesthetic used for blood collection: no
- Animals fasted: Not specified
- How many animals: not specified
- Parameters checked: Erythrocyte count,
hemoglobin concentration, hematocrit, leucocyte count and differential leukocyte count

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: 24 h before termination of exposure
- Anaesthetic used for blood collection: yes, ether
- Animals fasted: Yes 24 hours before
- How many animals:no data
- Parameters checked: alanine aminotransferase, aspartate aminotransferase, sorbitol dehydrogenase, alkaline phosphatase, total protein, albumin and glucose, and electrolytes — sodium, potassium, calcium, chloride

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: rotarod performeance once per month; hot plate response (latency of paw-lick response) at study termination
- Dose groups that were examined: all

Sacrifice and pathology:

Organ weights: heart, lungs, liver, spleen, kidneys, adrenals, testes

Liver: microsomal monooxygenases and lipid peroxidation
livers were homogenized to yield a 25% homogenate.
The activity of aniline p-hydroxylase (EC 1.14.1.1) was assayed in 9000 g postmitochondrial supernatants of the liver according to Holtzman and Gillette (6) as adopted by Wiśniewska-Knypl and Jabłońska (21).
In liver microsome Cytochrome P —450 was determined according to Omura and Sato by Carbon monoxidedifference spectra of dithionite-reduced microsomes between 490 and 450 nm using Beckman ACTA CIII spectrophotometr and extinction coeficient of 91 m m ol-1 cm -1 was employed for quantifying cytochrome P —450.
Lipid peroxidation in fresh microsomal membranes was evaluated on the basis of detection of thiobarbituric acidreactive substance according to M ihara et al
An extinction coefficient of 1.56 x 10-5 m m ol-1 according to Wills (20) was used for malondialdehyde formation.
For assay of triglycerides, hepatic lipids were extracted by the method of Folch et al. (4): liver slices were homogenized with 20 volumes of chloroform-methanol (2:1, v/v) at 45°C and the extract washed with 0.1 mol NaCl, evaporated under vacuum and the residues dissolved in chloroform. Triglycerides were determined with a standard enzymatic kit of Boehringer-Mannheim.
“Test Combination-Triglycerides (neutral fat)” taking for analysis a lipid extract equivalent to 10 — 20 mg of fresh liver, and the decrease of NADH was
measured at 340 nm in a Perkin-Elmer Lambda 15 spectrophotometer. Concentration of triglycerides in the liver were adapted for nmol per g tissue using a factor 1.14 (mol wt. of glycerol trioleate = 885.4).

Statistics:

ANOVA, Dunnet's test and Fisher Exact test

Clinical signs:

not examined

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

at both concentration significantly increased after 1 and 2 months (no relationhip with dose). No effect at 3 months

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:

effects observed, treatment-related

Description (incidence and severity):

sign decreased Hb at both concentrations (no concentration response relationship)
sign decreased red bloodcells at high concentration (decreased at low concentration) --> related with concentration
sign increase of eosinophils at high concentration (increased at low concentration) --> related with concentration

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

effects observed, treatment-related

Description (incidence and severity):

Dose related significant increase of failures in rotarod test (increasing over time)
Significant decrease of decrease in latency of the paw-lick response at low and high concentration (no concentration related effect)

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

not examined

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Other effects:

effects observed, treatment-related

Description (incidence and severity):

sign dose related increase of lipid peroxidation (15% at low concentration and 30% at high concentration)

Dose descriptor:

LOAEC

Effect level:

154 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

behaviour (functional findings)

haematology

other: effect on lipid peroxidation

Critical effects observed:

yes

Lowest effective dose / conc.:

154 mg/m³ air

System:

other: behavioural effects

Organ:

other: cannot be specified

Treatment related:

yes

Dose response relationship:

yes

The endpoints investigated in this study are too limited to allow a defnitive conclusion on 1 -butanol toxicity after repeated inhalation exposure.

Conclusions:

Effects of butanol on behaviour and lipid peroxidation in in liver cells became apparent at 154 mg/m3

Executive summary:

Rats were exposed to vapours of n-butanol at concentrations of 50 and 100 ppm 6 h/day, 5 days/week for 3 months (154 and 308 mg/m3). No significant changes in body weight gain, in absolute and relative organ weights and clinical biochemistry parameters were observed. N-butanol caused significant disturbances of motor coordination disturbances at 100 ppm. Significant increase in sensitivity to pain in animals exposed to n-butyl alcohol was observed. N-Butyl alcohol provoked the increase of lipid peroxidation in hepatic microsomes without any induction of cytochrome P450 monooxygenases.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LOAEC

154 mg/m³

Study duration:

subchronic

Species:

rat

Quality of whole database:

Based on exposure during 6 hours/day 5 days/week. As butan-1-ol is the most volatile hydrolysis product. Data on aluminium will not be taken into account for toxicity via inhalation.

System:

other: behavioural effects, haematology and lipid peroxidation

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

Mode of Action Analysis / Human Relevance Framework

Upon contact with water or moisture (e.g. within mucous membranes) aluminium tributanolate hydrolyses immediately to butan-1-ol and aluminium 3+ cations (as hydroxide and oxyhydroxide). Hence, toxicity is determined by the toxicity of these two species. Further details on the appraoch are provided in the attachment to section 13.

Additional information

For risk assessment purposes the lowest derived occupational exposure limit for butan-1-ol (61 mg/m3) will be used as starting point for inhalation exposure, as absorption of butan-1-ol is expected to be >100 times higher than that of aluminium hydroxide. For dermal toxicity the NOAEL from the oral repeated dose study on butan-1-ol will be used as starting point, also based on the large difference is absorption to be expected between butan-1-ol and aluminium (III) compounds.

Justification for classification or non-classification

Based on a weight of evidence approach building on subacute and subchronic studies performed with butan-1-ol and different Al3+ compounds it can be concluded that aluminium tributanolate does not require classification for Systemic Target Organ Toxicity, Repeat Exposure (STOT RE) according to CLP (Regulation EC No 1282/2008).