(2E)-2-methyl-3-phenylacrylaldehyde

Endpoint summary

Description of key information

Acute Oral Toxicity: LD₅₀ = 2050 mg/Kg

Acute Dermal Toxicity: LD₅₀ > 5000 mg/Kg

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:

1973

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

no guideline followed

Principles of method if other than guideline:

No exact guideline or method detailed in report.

GLP compliance:

not specified

Remarks:

pre-GLP report

Test type:

fixed dose procedure

Limit test:

no

Specific details on test material used for the study:

Test material was described with the generic name "alpha-methylcinnamaldehyde". As manufactured by Innospec, the product met the criteria of > 80% trans-isomer, supporting that the test material was the isomer better described as CAS 15174-47-7.

Species:

rat

Strain:

not specified

Sex:

not specified

Details on test animals or test system and environmental conditions:

Compound No. RIFM 72-257

Route of administration:

oral: unspecified

Vehicle:

not specified

Doses:

1.64, 2.05, 2.56, 3.20, 5.00 g/Kg

No. of animals per sex per dose:

10 animals per dose, no sex details given

Control animals:

not specified

Key result

Sex:

not specified

Dose descriptor:

LD50

Effect level:

ca. 2 050 mg/kg bw

95% CL:

> 1.83 - < 2.27

Mortality:

On day 1 post oral exposure mortality was observed as follows:
1.64 g/Kg - 2 rats dead
2.05 g/Kg - 4 rats dead
2.56 g/Kg - 8 rats dead
3.20 g/Kg - 10 rats dead
5.00 g/Kg - 10 rats dead

Clinical signs:

other: The animals which died experienced sluggishness prior to death

Table 1. Distribution of Mortality
Dose (g/Kg)	Observation Day														Mortality
	1	2	3	4	5	6	7	8	9	10	11	12	13	14
1.64	2	0	0	0	0	0	0	0	0	0	0	0	0	0	2/10
2.05	4	0	0	0	0	0	0	0	0	0	0	0	0	0	4/10
2.56	8	0	0	0	0	0	0	0	0	0	0	0	0	0	8/10
3.20	10	0	0	0	0	0	0	0	0	0	0	0	0	0	10/10
5.00	10	0	0	0	0	0	0	0	0	0	0	0	0	0	10/10

Interpretation of results:

other: Not classified

Remarks:

Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) of substances and mixtures

Conclusions:

Based on observed mortality, the acute oral LD50 of Alpha methyl cinnamic aldehyde was determined to be 2050 mg/Kg (95% confidence interval = 1830 – 2270 mg/Kg).

Executive summary:

In a key fixed dose oral toxicity study, the test material (Alpha methyl cinnamic aldehyde) was orally administered to rats (10/dose) at doses of 1.64, 2.05, 2.56. 3.20, or 5.0 g/Kg.

 

All animals treated at ≥3.20 g/Kg died on day one. At 1.64 g/Kg, 2/10 animals died while 4/10 and 8/10 animals died post exposure to the test material at doses of 2.05 and 2.56 g/Kg, respectively.

 

The acute oral LD₅₀ of Alpha methyl cinnamic aldehyde was therefore determined to be 2050 mg/Kg (95% confidence interval = 1830 – 2270 mg/Kg).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 050 mg/kg bw

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:

1973

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

no guideline followed

Principles of method if other than guideline:

No guideline or method detailed in report.

GLP compliance:

no

Remarks:

Pre-GLP study.

Test type:

fixed dose procedure

Limit test:

no

Specific details on test material used for the study:

Test material was described with the generic name "alpha-methylcinnamaldehyde". As manufactured by Innospec, the product met the criteria of > 80% trans-isomer, supporting that the test material was the isomer better described as CAS 15174-47-7.

Compound No.: RIFM 72-257
Clear liquid

Species:

rabbit

Strain:

not specified

Sex:

not specified

Type of coverage:

not specified

Vehicle:

not specified

Details on dermal exposure:

Not specified

Duration of exposure:

Not specified

Doses:

5 gm/Kg bw

No. of animals per sex per dose:

10 animals

Control animals:

not specified

Key result

Sex:

not specified

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed at 5000 mg/Kg bw

Table 1. Distribution of Mortality
Dose (g/Kg)	Observation Day														Mortality
	1	2	3	4	5	6	7	8	9	10	11	12	13	14
5.0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/10

Interpretation of results:

other: Not classified

Remarks:

Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) of substances and mixtures

Conclusions:

The acute dermal LD50 of Alpha methyl cinnamic aldehyde was determined to be >5000 mg/Kg.

Executive summary:

In a key acute dermal toxicity study, the test material (Alpha methyl cinnamic aldehyde) was dermally administered to rabbits (10/dose) at a dose of 5000 mg/kg (5 g/kg).

 

No mortality was observed through the study period.

 

The acute dermal LD₅₀ of Alpha methyl cinnamic aldehyde was therefore determined to be >5000 mg/kg.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

> 5 000 mg/kg bw

Additional information

Acute Oral Toxicity

In a key fixed dose oral toxicity study (Toxicological Resources, 1973a), the test material (Alpha methyl cinnamic aldehyde) was orally administered to rats (10/dose) at doses of 1.64, 2.05, 2.56. 3.20, or 5.0 g/Kg. All animals treated at ≥3.20 g/kg died on day one. At 1.64 g/kg, 2/10 animals died while 4/10 and 8/10 animals died post exposure to the test material at doses of 2.05 and 2.56 g/Kg, respectively. The acute oral LD₅₀ of Alpha methyl cinnamic aldehyde was therefore determined to be 2050 mg/kg (95% confidence interval = 1830 – 2270 mg/Kg).

Acute Dermal Toxicity

In a key acute dermal toxicity study (Toxicological Resources, 1973b), the test material (Alpha methyl cinnamic aldehyde) was dermally administered to rabbits (10/dose) at a dose of 5000 mg/Kg (5 g/kg). No mortality was observed through the study period. The acute dermal LD₅₀ of Alpha methyl cinnamic aldehyde was therefore determined to be >5000 mg/Kg.

 

Acute Inhalation Toxicity

Inhalation is not the primary or secondary route of exposure. Two studies on the primary (oral) and secondary (dermal) routes of exposure are available.

Justification for classification or non-classification

Based on an acute oral LD₅₀ of 2050 mg/kg bw and an acute dermal LD₅₀ of >5000 mg/kg bw, Cyprinal (alpha methyl cinnamic aldehyde) is not classified for acute lethality by the oral or dermal routes of exposure under EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008. For non-EU countries, the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) defines a fifth category for acute toxicity for chemicals with oral LD₅₀ values between 2000 and 5000 mg/Kg bw. Based on the results of one acute oral toxicity study, alpha methyl cinnamic aldehyde meets the criteria for a Category 5 classification under UN GHS for acute oral toxicity.