Tangor, Murcote, ext.

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

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

Adequacy of study:

supporting study

Study period:

1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study designed to evaluate effects of substance on kidneys of rats: dosing 5 days/week instead of 7 days/week; haematological and clinical biochemical test not followed.

Cross-reference

Reason / purpose for cross-reference:

read-across: supporting information

Reference

Endpoint:

sub-chronic toxicity: oral

Type of information:

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

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study designed to evaluate effects of substance on kidneys of rats: dosing 5 days/week instead of 7 days/week; haematological and clinical biochemical test not followed. Furthermore, due to the read-across purpose it was given a Klimisch 2 rating, in accordance with the ECHA Practical guide #6 on the reporting of read-across in IUCLID. The justification for read across is provided in the attached background material of the chapter summary.

Justification for type of information:

The read across justification is attached below

Reason / purpose for cross-reference:

read-across source

Dose descriptor:

NOAEL

Effect level:

5 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Basis for effect level:

other: chronic nephrosis and a dose-related trend in the increased relative weights of the kidney and liver were observed at 30 and 75 mg/kg bw/day

Dose descriptor:

LOAEL

Effect level:

30 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Critical effects observed:

not specified

Preliminary acute toxicity study:

- An increase in the incidence and severity of hyaline droplets was observed in the kidneys of males only. This histological change was accompanied by a treatment-related increase in alpha 2µ-globulin in males only and a greater accumulation of radioactivity in renal cortex of the male rat compared with that in the females dosed with [14C]d-limonene.

 

Subchronic toxicity study:

- Incidence and type of gross pathological lesions observed at necropsy, the cumulative body-weight gain, feed consumption and feed efficiency for treated males did not differ significantly from those of the control males.

- Linear regression analyses indicated a dose-related trend in the increased relative weights of the kidney and liver at 30 and 75 mg/kg bw/day. Histological examination of kidney tissue confirmed that d-limonene induced changes characterized by hyaline droplets, granular casts at the corticomedullary junction and multiple cortical changes collectively classified as chronic nephrosis.

- At the earliest necropsy, 8 days after the start of the treatment, it was evident that d-limonene exacerbated the hyaline droplets at 10 mg/kg bw/day.

- The no-observable-effect level for these effects was 5 mg/kg bw/day.

Conclusions:

Under the test conditions, the NOAEL and LOAEL were considered to be 5 and 30 mg/kg bw/day, respectively, based on observation of chronic nephrosis. Mechanisms and specificity of toxicity of d-limonene on kidneys of male rats and its non relevance for humans are well known.

Executive summary:

In a subchronic toxicity study, d-limonene was administered through gavage to groups of 5 or 10 male Fisher-344 rats/dose mixed in corn oil at dose levels of 0, 2, 5, 10, 30 and 75 mg/kg bw/day for 13 weeks (5 days/week). Animals were observed and weighed daily, and feed consumption was recorded weekly. Rats from selected dose groups received interim necropsies from Days 8-29, while all groups were necropsied at the end of the study. In the preliminary acute toxicity study, d-limonene (200 mg/kg bw; 200 µCi/kg bw in corn oil) was administered to a group of male and female Fischer 344 rats by oral gavage. After 24 hours, an increase in the incidence and severity of hyaline droplets containing alpha-2µ-globulin was observed in the kidneys of males only.

 

In the main study, incidence and type of gross pathological lesions observed at necropsy, the cumulative body-weight gain, feed consumption and feed efficiency for treated males did not differ significantly from those of the control males. Linear regression analyses indicated a dose-related trend in the increased relative weights of the kidney and liver at 30 and 75 mg/kg bw/day. Histological examination of kidney tissue confirmed induction of chronic nephrosis characterized by hyaline droplets, granular casts at the corticomedullary junction and multiple cortical changes. At the earliest necropsy, 8 days after the start of the treatment, it was evident that d-limonene exacerbated the hyaline droplets at the 10 mg/kg body weight dose.

 

Under the test conditions, the NOAEL and LOAEL were considered to be 5 and 30 mg/kg bw/day, respectively, but mechanisms and specificity of toxicity of d-limonene on kidneys of male rats and its non relevance for humans are well known.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1989

Materials and methods

Principles of method if other than guideline:

Study designed to evaluate effects of substance on kidneys of rats: dosing 5 days/week instead of 7 days/week; haematological and clinical biochemical test not followed

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

(R)-p-mentha-1,8-diene

EC Number:

227-813-5

EC Name:

(R)-p-mentha-1,8-diene

Cas Number:

5989-27-5

Molecular formula:

C10H16

IUPAC Name:

(4R)-1-methyl-4-(prop-1-en-2-yl)cyclohexene

Details on test material:

- Name of test material (as cited in study report): d-limonene
- Source: Sigma Chemical Company (St Louis, MO, USA)
- Analytical purity: > 99% (GC)
- Storage condition of test material: Stored refrigerated in amber bottles

Radiolabelled d-limonene [9-14C]
- Source: Wizard Laboratories (Davies, CA, USA)
- Radiochemical purity (if radiolabelling): 99% (GC)
- Specific activity (if radiolabelling): 8.7 mCi/mmol

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

5 days/week

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 2, 5, 10, 30 and 75 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

- At 0, 10 and 75 mg/kg bw/day: 5 or 10 males
- At 2, 5 and 30 mg/kg bw/day: 10 males

Control animals:

yes, concurrent vehicle

Results and discussion

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

5 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Basis for effect level:

other: chronic nephrosis and a dose-related trend in the increased relative weights of the kidney and liver were observed at 30 and 75 mg/kg bw/day

2

Dose descriptor:

LOAEL

Effect level:

30 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Preliminary acute toxicity study:

- An increase in the incidence and severity of hyaline droplets was observed in the kidneys of males only. This histological change was accompanied by a treatment-related increase in alpha 2µ-globulin in males only and a greater accumulation of radioactivity in renal cortex of the male rat compared with that in the females dosed with [14C]d-limonene.

 

Subchronic toxicity study:

- Incidence and type of gross pathological lesions observed at necropsy, the cumulative body-weight gain, feed consumption and feed efficiency for treated males did not differ significantly from those of the control males.

- Linear regression analyses indicated a dose-related trend in the increased relative weights of the kidney and liver at 30 and 75 mg/kg bw/day. Histological examination of kidney tissue confirmed that d-limonene induced changes characterized by hyaline droplets, granular casts at the corticomedullary junction and multiple cortical changes collectively classified as chronic nephrosis.

- At the earliest necropsy, 8 days after the start of the treatment, it was evident that d-limonene exacerbated the hyaline droplets at 10 mg/kg bw/day.

- The no-observable-effect level for these effects was 5 mg/kg bw/day.

Applicant's summary and conclusion

Conclusions:

Under the test conditions, the NOAEL and LOAEL were considered to be 5 and 30 mg/kg bw/day, respectively, based on observation of chronic nephrosis. Mechanisms and specificity of toxicity of d-limonene on kidneys of male rats and its non relevance for humans are well known.

Executive summary:

In a subchronic toxicity study, d-limonene was administered through gavage to groups of 5 or 10 male Fisher-344 rats/dose mixed in corn oil at dose levels of 0, 2, 5, 10, 30 and 75 mg/kg bw/day for 13 weeks (5 days/week). Animals were observed and weighed daily, and feed consumption was recorded weekly. Rats from selected dose groups received interim necropsies from Days 8-29, while all groups were necropsied at the end of the study. In the preliminary acute toxicity study, d-limonene (200 mg/kg bw; 200 µCi/kg bw in corn oil) was administered to a group of male and female Fischer 344 rats by oral gavage. After 24 hours, an increase in the incidence and severity of hyaline droplets containing alpha-2µ-globulin was observed in the kidneys of males only.

 

In the main study, incidence and type of gross pathological lesions observed at necropsy, the cumulative body-weight gain, feed consumption and feed efficiency for treated males did not differ significantly from those of the control males. Linear regression analyses indicated a dose-related trend in the increased relative weights of the kidney and liver at 30 and 75 mg/kg bw/day. Histological examination of kidney tissue confirmed induction of chronic nephrosis characterized by hyaline droplets, granular casts at the corticomedullary junction and multiple cortical changes. At the earliest necropsy, 8 days after the start of the treatment, it was evident that d-limonene exacerbated the hyaline droplets at the 10 mg/kg body weight dose.

 

Under the test conditions, the NOAEL and LOAEL were considered to be 5 and 30 mg/kg bw/day, respectively, but mechanisms and specificity of toxicity of d-limonene on kidneys of male rats and its non relevance for humans are well known.