Piperonal

Endpoint summary

Description of key information

After review of the available data, it has been concluded that heliotropin (piperonal) is of low acute toxicity following oral and dermal exposure.
The reported oral LD50 value in rats is 2,700 mg/kg body weight.  Clinical signs of systemic toxicity include excitation and tremors for several hours followed by depression and ataxia.  Deaths occurred between 2 hours and 5 days following dosing.
The reported dermal LD50 value in rats is > 5,000 mg/kg body weight, and no clinical signs of systemic toxicity or skin irritation or other dermal reactions were observed for up to 14 days following dermal administration.
Information is not available on the acute inhalation toxicity of heliotropin (piperonal).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 700 mg/kg bw

Quality of whole database:

The information is reliable and consistent with the database as a whole.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from March to August 1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Missing information on purity of test article.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: IFF Protocol No. DLD (9/7/79) supplied by International Flavors & Fragrances, Inc.

Deviations:

not specified

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

Missing information on purity.

Principles of method if other than guideline:

In a preliminary assay in which two rats of each sex were dosed by application of a prepared alcoholic solution of (crystal dissolved in diluent IFF 80-007) of the test substance to the skin at 5.0 g/kg body weight, there were no deaths during the 72 hour observation period.
Main test: The same dose was used on eight male and eight female albino rats in which the reactions were observed over a period of 14 days.

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Species:

rat

Strain:

other: Sprague-Dawley CD strain

Sex:

male/female

Details on test animals or test system and environmental conditions:

Sixteen (8 male and 8 female) young adult albino rats were used. The animals obtained from Charles River Breeding Labs (Wilmington, Mass.) were within the body weight range of 180-280 grams when assigned to the study (18 hours prior to dosing). The animals were housed singly in wire cages under standard laboratory conditions meeting the standards described in the "Guide for the care and use of laboratory animals [DHEW Publication No. (NIH) 78-23, Revised 1978]. The rats were fed Purina Rodent Laboratory Chow 5001 and allowed water ad libitum. Animals were acclimatized to the study room for seven days and were assigned to this study using a system of random numbers. The animals were individually numbered and were marked by ear tags. The entire study was identified by a colour coded label bearing a notation of the dose on each cage.
The animals were examined by a veterinarian and all animals assigned to the study had to be in good health and condition prior to the start of the study.

Type of coverage:

open

Vehicle:

other: alcohol

Details on dermal exposure:

On the day prior to treatment, the backs of the rats were clipped from the scapular region to the hips.
The test substance was applied evenly over the back using a B-D disposable syringe. The site of application was approximately that area bounded by the nape of the neck, the mid dorsum between pectoral and pelvic girdles and the lateral aspects of the scapulae, judged to comprise less than 30% of the body surface. The test article was allowed to remain in contact with the skin and open to the air for 24 hours after which any excess material was removed by wiping with a clean cloth. The day of dosing was designed Day 0.

Duration of exposure:

24 hours

Doses:

Based on the result of the preliminary test, 8 male and 8 female rats were treated with a single dose of 5.0 grams of the test article, administered per kilogram body weight. The volume of the prepared test article given to the rats was 1.0 mL/100 g body weight.

No. of animals per sex per dose:

In the preliminary test: 2 males and 2 females
In the main study: 8 males and 8 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: 1, 3, 5 and 24 hours following dosing and twice daily (once daily on weekend) for the remainder of the 14 day observation period.
- Frequency of weighing: the rats were weighted at day 0 and at day 14
- Necropsy: All the animals underwent a gross necropsy at the end of the experiment.
- Other examinations performed: mortality, clinical signs, body weight, macroscopic pathology (lungs, heart, liver, spleen, kidney, adrenals, bladder, stomach, intestines, skin, fur, orifices, peritoneal and pleural mucosa, and internal mesentery)

Statistics:

no data available

Preliminary study:

No animals died during the 72 hours observation period.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: None

Mortality:

There were no deaths in the eight males and eight females dosed with the test article.

Clinical signs:

other: There were no clinical signs of toxicity in any animal dosed with #80-007-03 at 5.0 g/Kg body weight. All animals appeared normal in health and behaviour throughout the 14 day observation period.

Gross pathology:

There were no signs indicative of toxicity in any of the sixteen animals necropsied at term (no findings reported in the lungs, heart, liver, spleen, kidney, adrenals, bladder, stomach, intestines, skin, fur, orifices, peritoneal and pleural mucosa, or internal mesentery).

Other findings:

No data available

The dermal LD₅₀was greater than 5000 mg/kg body weight.

Interpretation of results:

not classified

Remarks:

Migrated information under CLP REGULATION (EC) No 1272/2008 Criteria used for interpretation of results: other: REGULATION (EC) No 1272/2008 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL

Conclusions:

The dermal LD50 was greater than 5000 mg/kg body weight.

Executive summary:

None of the animals showed any clinical signs indicative of systemic toxicity. There were no deaths and all animals remained healthy throughout the study and gained weight in a normal manner, except for one female which lost 10 grams over the course of the study. At necropsy, none of the animals had any signs indicative of systemic toxicity (no findings reported in the lungs, heart, liver, spleen, kidney, adrenals, bladder, stomach, intestines, skin, fur, orifices, peritoneal and pleural mucosa, or internal mesentery). Based on these findings, the dermal LD₅₀ was reported to be > 5,000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Quality of whole database:

The information is reliable and consistent with the database as a whole.

Additional information

The acute oral toxicity of heliotropin (piperonal) in rats was reported in 3 publications, all of which appear to report the same set of data (Jenner et al., 1964; Taylor et al., 1964; Hagan et al., 1965). Two of the publications were judged to be reliable with restrictions (Jenner et al., 1964; Taylor et al., 1964) while the third was judged to be unreliable due to methodological and reporting deficiencies (Hagan et al., 1965). Based on the cumulative information provided in the 3 publications, young Osborne-Mendel rats (5 rats/sex) were administered oral (gavage) doses of heliotropin (piperonal) as a 25% solution in corn oil. Animals were fasted for 18 hours prior to dosing and were observed for up to 2 weeks post-dosing. Signs of toxicity included excitation and tremors for several hours followed by depression and ataxia, and deaths were reported to occur from between 2 hours and 5 days post-dosing. Each of these publications reported an oral LD₅₀ value for heliotropin (piperonal) of 2,700 mg/kg body weight (with a 95% confidence interval of 2,350 to 3,100 mg/kg body weight).

The acute dermal toxicity of heliotropin (piperonal) was evaluated in a GLP-compliant study by Cosmopolitan Safety Evaluation (1980) that was conducted in conformity with IFF Protocol No. DLD (9/7/79) supplied by International Flavors and Fragrances. Sixteen Sprague-Dawley CD rats (8/sex) weighing between 180 and 280 grams were clipped on the day prior to dosing. The test substance was prepared in alcohol and applied onto the skin of the back at a dose of 5,000 mg/kg body weight. The volume of solution administered was 10 mL/kg body weight and the area of skin to which the dose was applied was reported to comprise less than 30% of the body surface. The test article was allowed to remain in contact with the skin and open to the air for 24 hours after which excess material was removed with a clean cloth. Oral exposure was prevented by housing the animals individually. Animals were observed 1, 3, 5, and 24 hours post-dosing and twice daily (once daily on weekends) for the remainder of the 14-day observation period. None of the animals showed any clinical signs indicative of systemic toxicity. There were no deaths and all animals remained healthy throughout the study; the majority gained weight in a normal manner, except for one female which lost 10 grams over the course of the study. At necropsy, none of the animals had any signs indicative of systemic toxicity (no findings reported in the lungs, heart, liver, spleen, kidney, adrenals, bladder, stomach, intestines, skin, fur, orifices, peritoneal and pleural mucosa, or internal mesentery). Based on these findings, the dermal LD₅₀was reported to be > 5,000 mg/kg body weight.

In accordance with column 2 of REACH Annex VIII, the acute toxicity by inhalation study (required in section 8.5.2) does not need to be conducted as inhalation exposure is not anticipated given the low vapour pressure of heliotropin (piperonal) and as acute toxicity studies are available for the oral and dermal routes of exposure.

Justification for selection of acute toxicity – oral endpoint
Weight of evidence for acute oral toxicity is based on information provided in 3 publications.

Justification for selection of acute toxicity – dermal endpoint
A reliable acute dermal toxicity study is available.

Justification for classification or non-classification

The acute oral LD50 is > 2000 mg/kg bw (i.e., 2700 mg/kg bw). The acute dermal LD50 is > 2000 mg/kg bw (i.e., 5000 mg/kg bw). As a result, the substance does not meet the criteria for classification according to Regulation (EC) No 1272/2008, Annex I section 3.1.

No clinical signs of toxicity were reported in any of the acute single exposure studies. As a result, the substance does not meet the criteria for classification according to Regulation (EC) No 1272/2008, Annex I section 3.8.