Naphthenic acids, potassium salts

Endpoint summary

Description of key information

ACUTE TOXICITY: ORAL
- LD50 >2000 mg/kg bodyweight to female Wistar strain rats
ACUTE TOXICITY: DERMAL
- LD50 of naphthenic acids >3160 mg/kg in male and female New Zealand White rabbits
- LD50 of naphthenic acids >20 000 mg/kg in male and female New Zealand White rabbits
- LD50 of potassium nitrate >5000 mg/kg bw in male and female Sprague-Dawley rats

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17 July 2012 to 2 August 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF, 12 Nohsan, Notification No. 8147, 2011; including the most recent partial revisions

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: Crl:WI (Han) (outbred, SPF-Quality).
- Age at study initiation: Approximately 9 weeks old.
- Weight at study initiation: 163 to 176 g on the first day of the test. Bodyweight variation did not exceed ± 20 % of the sex mean.
- Fasting period before study: Yes. Animals were deprived of food overnight prior to dosing and until 3 to 4 hours after administration of the test material.
- Housing: Group housing of 3 animals per cage in labelled cages containing sterilised sawdust as bedding material and paper as cage-enrichment.
- Diet (e.g. ad libitum): Free access to pelleted rodent diet.
- Water (e.g. ad libitum): Free access to tap water.
- Acclimation period: At least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 to 24 °C.
- Humidity (%): 40 to 70 %.
- Air changes (per hr): Approximately 15 room air changes/hour.
- Photoperiod (hrs dark / hrs light): 12 hour light/12 hour dark cycle.

IN-LIFE DATES: From: 17 July 2012 To: 2 August 2012

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 2.00 mL/kg bodyweight.
Density of the test material was 1 g/cm³. Therefore the dose volume was calculated as dose level (g/kg) / density (g/mL).

Doses:

2000 mg/kg bodyweight

No. of animals per sex per dose:

6 female animals; dosed in two groups of 3.

Control animals:

no

Details on study design:

The test material was assessed by stepwise treatment of groups of 3 females. The first group was treated at a dose level of 2000 mg/kg. The absence or presence of mortality of animals dosed at one step determined the next step, based on the test procedure defined in the guidelines. The onset, duration and severity of the signs of toxicity were taken into account for determination of the time interval between the dose groups.

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: Animals were observed for mortality/viability twice daily. Animals were weighed on day 1 (prior to dosing) and on days 8 and 15.
At periodic intervals on the day of dosing and once daily thereafter clinical signs were noted. The symptoms were graded according to fixed scales and the time of onset, degree and duration were recorded.
- Necropsy of survivors performed: Yes. At the end of the observation period, all animals were sacrificed by oxygen/carbon dioxide procedure. Descriptions of all internal macroscopic abnormalities were recorded.

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There was no mortality.

Clinical signs:

other: Hunched posture was exhibited by two animals on day 1 of the study.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study, the oral LD50 of the test material was established to be >2000 mg/kg bodyweight and as such requires no classification in accordance with EU criteria.

Executive summary:

The acute oral toxicity of the test material was investigated in accordance with the standardised guidelines OECD 423, EU Method B.1 tris, EPA OPPTS 870.1100 and JMAFF 12 Nohsan, Notification No. 8147.

The undiluted test material was administered by gavage to two subsequent groups of three female Wistar rats at a dose level of 2000 mg/kg. The animals were observed for 15 days before being subjected to necropsy.

No mortality was seen throughout the study; clinical signs included two animals showing hunched posture on day 1 after dosing. Bodyweight gains were considered to be normal and no macroscopic abnormalities were observed at necropsy.

Under the conditions of this study, the oral LD50 of the test material was established to be >2000 mg/kg bodyweight and as such requires no classification in accordance with EU criteria.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The key study was conducted under GLP conditions in accordance with the standardised guidelines OECD 423 and EU Method B.1 tris. It was assigned a reliability score of 1 in accordance with the criteria detailed by Klimisch (1997).

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The first study on the read across material naphthenic acids was conducted broadly in accordance with the principles of the standardised guideline OECD 402. It was assigned a reliability score of 2 in accordance with the criteria detailed by Klimisch (1997).
The second study on the read across material naphthenic acids was conducted broadly in accordance with the principles of the standardised guideline CFR 16 1500.40. It was assigned a reliability score of 2 in accordance with the criteria detailed by Klimisch (1997).
The study on the read across material potassium nitrate was carried out in accordance with the standardised OECD 402 guideline under GLP conditions. It was assigned a reliability score of 2 in accordance with the criteria detailed by Klimisch (1997).

Additional information

Acute Toxicity: Oral

The acute oral toxicity of the test material was investigated in accordance with the standardised guidelines OECD 423, EU Method B.1 tris, EPA OPPTS 870.1100 and JMAFF 12 Nohsan, Notification No. 8147.

The undiluted test material was administered by gavage to two subsequent groups of three female Wistar rats at a dose level of 2000 mg/kg. The animals were observed for 15 days before being subjected to necropsy.

No mortality was seen throughout the study; clinical signs included two animals showing hunched posture on day 1 after dosing. Bodyweight gains were considered to be normal and no macroscopic abnormalities were observed at necropsy.

Under the conditions of this study, the oral LD50 of the test material was established to be >2000 mg/kg bodyweight and as such requires no classification in accordance with EU criteria.

 

Acute Toxicity: Inhalation

In accordance with the Column 2 adaptation of Annex VIII of Regulation (EC) 1907/2006 (REACH), it is considered justified to omit the acute toxicity by the inhalation route study (required under point 8.5.2) as testing by this route is inappropriate. Exposure via the inhalation route is not relevant due to the substance being a viscous liquid with a low vapour pressure; therefore the acute oral and acute dermal studies are deemed more appropriate to address acute toxicity exposure.

 

Acute Toxicity: Dermal

In the first study, the potential of the read across material naphthenic acids to cause acute toxicological effects when administered via the dermal route was investigated in a study conducted broadly in accordance with the principles of the standardised guideline OECD 402.

The test material was applied at a limit dose of 3160 mg/kg to the abraded abdomen skin of two male and two female New Zealand White rabbits. The test site was covered with an occlusive dressing for 24 hours. The animals were observed for mortality, clinical signs and dermal irritation for 14 days.

Under the conditions of this study, the LD50 was determined to be >3160 mg/kg and therefore the test material requires no classification in accordance with EU criteria.

 

In the second study, the potential of the read across material naphthenic acids to cause acute toxicological effects when administered via the dermal route was investigated in a study conducted broadly in accordance with the principles of the standardised guideline CFR 16 1500.40.

The test material was applied at a limit dose of 20 000 mg/kg to the skin on the trunk of six New Zealand White rabbits, three per sex. The skin of two males and one female was abraded. 

The test site was covered with an occlusive dressing for 24 hours. The animals were observed for mortality, clinical signs and dermal irritation for 14 days.

Under the conditions of this study, the LD50 was determined to be >20 000 mg/kg and therefore the test material requires no classification in accordance with EU criteria.

 

The potential of the read across material potassium nitrate to cause acute toxic effects when administered by the dermal route was investigated in accordance with the standardised guideline OECD 402 under GLP conditions.

The test material was administered once dermally to 5 male and 5 female Sprague Dawley rats at a limit dose of 5000 mg/kg bw. The test material was moistened with water to form a paste and the animals were exposed for 24 hours.

There was no mortality and no local or systemic effects related to administration of the test material. All animals appeared normal at necropsy.

Under the conditions of this study the LD50 was found to be >5000 mg/kg bw in male and female rats and therefore requires no classification in accordance with EU criteria.

Justification for selection of acute toxicity – oral endpoint
Only one study available.

Justification for selection of acute toxicity – inhalation endpoint
A data waiver has been submitted to address this endpoint.

Justification for selection of acute toxicity – dermal endpoint
This endpoint was addressed using a weight of evidence approach with read across data to structural analogues of the registered substance and so no single study was selected. Two studies are provided on naphthenic acids and one on potassium nitrate. In this respect it is considered that the data submitted provides an adequate reflection of the test material.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) 1272/2008, the test material does not require classification for acute toxicity.