2,2-dimethyl-1,3-propanediyl didecanoate

Endpoint summary

Description of key information

Acute toxicity: oral (target substance and read-across, equivalent/similar to OECD 401): LD50 (rat, m/f) > 2000 mg/kg bw

Acute toxicity: dermal and inhalation: Data waived according to Annex VIII, Item 8.5, Column 2, of Regulation (EC) No. 1907/2006 (REACH).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

13 - 27 Aug 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

The analytical purity of the test substance was not specified. Body weight changes could not be not examined.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

mouse

Strain:

CD-1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Wilmington, USA
- Age at study initiation: adult animals
- Fasting period before study: animals were fasted 4 h prior to administration
- Housing: 5 animals of the same sex per cage, in stainless steel wire mesh cages
- Diet: Wayne Lab BloxR, ad libitum
- Water: tap water, ad libitum (analyses performed)
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 5.5 mL/kg

CLASS METHOD
- Rationale for the selection of the starting dose: upon sponsor's request

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5 males and 5 females

Control animals:

other: not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed 1 and 4 h after dosing (clinical signs, CNS effects and mortality) and daily for the rest of the observation period. Body weights were recorded at study initiation.
- Necropsy of survivors performed: yes

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the observation period.

Clinical signs:

other: No clinical signs of toxicity were observed up to the end of the 14-day observation period.

Gross pathology:

Necropsy revealed no substance-related findings.

Other findings:

Poor grooming was observed.

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

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

Remarks:

Summary of available data used for the endpoint assessment of the target substance

Adequacy of study:

weight of evidence

Justification for type of information:

refer to analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: Source: CAS 68855-18-5, Central Toxicology Laboratory, 1996

All analogue source substances (2,2-dimethyl-1,3-propanediyl dioctanoate (CAS 31335-74-7), heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5) and fatty acids, C8-10, mixed esters with neopentyl glycol and trimethylolpropane (CAS 97281-24-8)) reavealed LD50 values of > 2000 mg/kg bw. No mortality occurred in any of the studies. No clinical signs of toxicity were observed up to the end of the observation periods. No effect on body weights was noted and necropsy examination revealed no toxicologically relevant substance-related findings. The result of heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5) was chosen as representative as the test was best documented compared to the other two reports.

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.

Conclusions:

In 3/3 studies using three different analogue source substances no acute oral toxicity potential was observed. All LD50 values were determined to be > 2000 mg/kg bw. As explained in the analogue justification, this result is considered to be valid also for the target substance.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises adequate and reliable (Klimisch score 2) studies from various source substances with similar structures and intrinsic properties. Read-across is justified based on common precursors and hydrolysis products and consistent trends in environmental fate, ecotoxicological and toxicological profiles. The selected studies are thus sufficient to fulfil the standard information requirements set out in Annex VII, Item 8.5, in accordance with Annex XI, Item 1.5, of the REACH Regulation (EC) No. 1907/2006 (REACH).

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Oral acute toxicity

The acute oral toxicity of the target substance neopentyl glycol dicaprate (CAS 27841-06-1) was tested in a study performed equivalent or similar to OECD guideline 401 and complying with GLP provisions (Pharmakon, 1990a). Five female and five male CD-1 mice were orally exposed to the test item via gavage at a limit dose of 5000 mg/kg bw. During the 14-day observation period, the animals were subjected to clinical observations and weighing. A necropsy was performed after terminal sacrifice of the animals. No mortality occurred and no clinical signs of toxicity were apparent during the observation period. Effects on body weight could not be examined, because the ear tags of all animals were missing on Day 14. Necropsy revealed no substance-related findings. The oral LD50 value in mice was thus determined to be > 5000 mg/kg bw.

Since the study was performed in mice and no observations of body weight changes could be made at the end of the study due to missing ear tags, additional data from analogue source substances are included to adequately evaluate the acute toxicity potential of the target substance. Therefore, read-across from the analogue source substances 2,2-dimethyl-1,3-propanediyl dioctanoate (CAS 31335-74-7), heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5), and fatty acids, C8-10, mixed esters with neopentyl glycol and trimethylolpropane (CAS 97281-24-8) was performed in a Weight-of-Evidence approach.

An acute oral toxicity study with 2,2-dimethyl-1,3-propanediyl dioctanoate (CAS 31335-74-7) was performed equivalent or similar to OECD guideline 401 (Central Toxicology Laboratory, 1993). No information was given on GLP compliance. However, it was stated that the study was performed as a limit test. Two rats per sex (strain not specified) were orally administered the test item via gavage at a dose of 2000 mg/kg bw. During the 8-day observation period the animals were subjected to daily observations and weighing on Days 1 and 8. Macroscopic examination was performed after terminal sacrifice. No mortality occurred and no clinical signs of toxicity were observed during the study period. No effects on body weights were noted and necropsy revealed no treatment-related findings. The oral LD50 value in rats was > 2000 mg/kg bw.

Another acute oral toxicity study is available for heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5). The study was performed according to OECD guideline 401 (standard acute method) and observed GLP criteria (Central Toxicological Laboratory, 1996). In a preliminary study, the test item was administered by gavage to two Alderley Park albino rats (Alpk: APfSD) per sex at 2000 mg/kg bw (limit test). Five further animals per sex were then treated with the same dose for the main study. The animals were subjected to daily observations and determinations of body weights on test Days -1 (prior to fasting), 1, 3, between Days 4 and 6, and on Day 8 and 15. Macroscopic examination was performed after terminal sacrifice. No mortality occurred and no clinical signs of toxicity were observed during the study period. No effects on body weights were noted and necropsy revealed no treatment-related findings. The oral LD50 value in rats was > 2000 mg/kg bw.

The acute oral toxicity of fatty acids, C8-10, mixed esters with neopentyl glycol and trimethylolpropane (CAS 97281-24-8) was investigated in a study performed equivalent or similar to OECD guideline 401 (standard acute method, limit test) and in compliance with GLP (BASF, 1988). The test item was administered by gavage to five Wistar rats per sex at a dose of 2000 mg/kg bw. The animals were subjected to daily observations for clinical signs, and twice daily for morbidity and mortality. Body weights were determined weekly on test Days -1, 2, 7, and 14 and macroscopic examinations were performed after terminal sacrifice. No mortality occurred and no clinical signs of toxicity were observed during the study period. No effects on body weights were noted. Necropsy revealed for males haemangioma of the left renal lymph node in 1/5 animals, and mild hypoplasia of the right testis in 1/5 animals. 1/5 females showed high grade hydrometra and haemangioma of the left renal lymph node. The oral LD50 value in rats was > 2000 mg/kg bw.

Dermal acute toxicity and acute toxicity by inhalation

No data regarding the dermal acute toxicity of the target substance neopentyl glycol dicaprate (CAS 27841-06-1) are required based on the provisions of REACH (Regulation (EC) No. 1907/2006), Annex VIII, Item 8.5.3., Column 2, since the substance does not meet the criteria for classification as acute toxicity or STOT SE by the oral route and no systemic effects have been observed in in vivo studies with dermal exposure (e.g. skin irritation and skin sensitisation).

No study of the acute toxicity by inhalation is needed for the target substance because testing by the inhalation route is appropriate only if exposure of humans via inhalation is likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size. Since the substance has a very low vapour pressure (< 0.001 Pa at 20 °C) and no uses leading to the formation of aerosols are expected, the acute toxicity by the inhalation route of exposure is not considered to be relevant.

Conclusion on acute toxicity

In summary, a study conducted with the target substance and three studies performed with adequate analogue source substances are available for acute oral toxicity. All studies resulted in oral LD50 values of > 2000 mg/kg bw, thus being well above the relevant threshold for classification. The data available indicate a very low level of acute oral toxicity for the target substance. Hence, no hazard for acute oral toxicity is identified.

Justification for classification or non-classification

The available data on acute oral toxicity of both, the target substance neopentyl glycol dicaprate (CAS 27841-06-1) and from adequate analogue source substances do not meet the classification criteria according to the CLP Regulation (EC) No. 1272/2008. Data are, therefore, conclusive but not sufficient for classification.