(E,E)-2,4-Hexadienal

96.13

96.13

1698401

205-564-3

878K4I6N7T

TSCA listed

DTXSID2025391

Colorless

29121900

17.1

1.37 /Estimated/

Yellow liquid; powerful but sweet-green aroma, in dilution pleasant citrusy green

0.895 g/mL at 20 °C 0.871 g/mL at 25 °C (lit.)

-16.5°C

69 °C/20 mmHg (lit.)

154 °F

n20/D1.541(lit.)

It is Insoluble in water, but soluble in ethanol.

2-8°C

4.8 mm Hg @ 25 deg C /Estimated/

>1 (vs air)

Oral-Rat  LD50: 300 mg/kg

Open flame, heat, oxidants are combustible; burning emits irritating smoke

at 10.00 % in dipropylene glycol. sweet green spicy floral citrus

1.0×100mol/(m3Pa) at 25℃, Buttery et al. (1971)

Hydroxyl radical reaction rate constant = 6.5X10-11 cu cm/molec-sec @ 25 °C /Estimated/|Ozone reaction rate constant = 8.4X10-16 cu cm/molec-sec @ 25 °C /Estimated/|Colorless to yellow liquid; pungent green or citrus odor /trans,trans-isomer + cis, trans-isomer-)

2,4-Hexadienal|C*: Compounds that autopolymerize due to peroxide formation if inhibitors are depleated or not present|Bretherick's|An explosive polymerization occured on an industial scale. See Bretherick's.|Steele, A. B. et al., Chem. Engrg., 1959, 66(8), 166

2-8°C

III

6.1

UN 2922 8/PG 3

3

T,Xi,Xn

26-36/37/39-45-36

WG1925000

T,Xi,Xn

The warehouse is ventilated, low temperature and dry; lightly loaded and unloaded, stored separately from oxidants and acids

Irritant

Stable. Combustible. Incompatible with strong reducing agents, strong bases, strong oxidizing agents.

P280-P301 + P310-P305 + P351 + P338-P310

22-24-34-43-36/37/38-20/21/22

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

UN 2922 8/PG 3

|Danger|H226 (100%): Flammable liquid and vapor [Warning Flammable liquids]|P210, P233, P240, P241, P242, P243, P261, P264, P270, P272, P280, P301+P312, P302+P352, P303+P361+P353, P312, P321, P322, P330, P332+P313, P333+P313, P361, P362, P363, P370+P378, P403+P235, P405, and P501|Aggregated GHS information provided by 88 companies from 1 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H226 (97.26%): Flammable liquid and vapor [Warning Flammable liquids]|P210, P233, P240, P241, P242, P243, P261, P264, P270, P272, P280, P301+P312, P302+P352, P303+P361+P353, P305+P351+P338, P312, P321, P322, P330, P332+P313, P333+P313, P337+P313, P361, P362, P363, P370+P378, P403+P235, P405, and P501|Aggregated GHS information provided by 1642 companies from 8 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H302: Harmful if swallowed [Warning Acute toxicity, oral]|P201, P202, P261, P264, P270, P272, P280, P281, P301+P312, P302+P352, P308+P313, P312, P321, P322, P330, P333+P313, P361, P363, P405, and P501|H227: Combustible liquid [Warning Flammable liquids]|P201, P202, P210, P260, P264, P270, P280, P281, P301+P310, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P312, P321, P322, P330, P361, P363, P370+P378, P403+P235, P405, and P501

highly toxic

LD50 Rat oral 300 mg/kg /from table/|LD50 Rabbit skin 270 uL/kg /from table/

2,4-Hexadienal, a colorless to yellow liquid with a pungent "green" or citrus odor, is used as a food additive for flavor enhancement, as a fragrance agent, as a starting material or intermediate in synthetic reactions in the chemical and pharmaceutical industries, as a fumigant, and as a corrosion inhibitor for steel. 2,4-Hexadienal was nominated for study by the National Cancer Institute because of the potential for carcinogenicity based on its alpha,beta-unsaturated aldehyde structure and the potential link between exposure to lipid peroxidation products in the diet and human malignancies. The commercial product is a mixture containing chiefly trans,trans-2,4-hexadienal in equilibrium with cis,trans-2,4-hexadienal. Male and female F344/N rats and B6C3F1 mice received 2,4-hexadienal (89% trans,trans; 11% cis,trans) in corn oil by gavage for 16 days, 14 weeks, or 2 years. Tissues and plasma from dosed rats were examined for malondialdehyde and glutathione concentrations, and DNA adducts were characterized in liver and forestomach samples from dosed rats and mice. Genetic toxicology studies were conducted in Salmonella typhimurium, rat and mouse bone marrow cells, and mouse peripheral blood erythrocytes. 16-DAY STUDY IN RATS: Groups of five male and five female rats were administered 0, 3, 9, 27, 80, or 240 mg 2,4-hexadienal/kg body weight in corn oil by gavage, 5 days per week, for 16 days. Three male and three female 240 mg/kg rats died before the end of the study. Mean body weight gains of 240 mg/kg rats were significantly less than those of the vehicle controls. Clinical findings included diarrhea, ataxia, lethargy, and nasal/eye discharge in males, and lethargy, paleness, and abnormal breathing in females in the 240 mg/kg groups. Liver weights of 240 mg/kg females were significantly greater than those of the vehicle controls. Gross and microscopic lesions indicative of forestomach necrosis and ulceration were present in most 240 mg/kg rats, and forestomach epithelial hyperplasia was microscopically evident in most 80 mg/kg rats. 16-DAY STUDY IN MICE: Groups of five male and five female mice were administered 2,4-hexadienal in corn oil by gavage at doses of 0, 3, 9, 27, 80, or 240 mg/kg, 5 days per week, for 16 days. Chemical-related deaths occurred in one male and one female in the 240 mg/kg groups. Female mice in the 240 mg/kg group lost weight during the study. Gross and microscopic lesions indicative of forestomach necrosis and ulceration were present in all 240 mg/kg mice, and forestomach epithelial hyperplasia and hyperkeratosis were microscopically evident in 80 mg/kg mice. 14-WEEK STUDY IN RATS: Groups of 10 male and 10 female rats were administered 2,4-hexadienal in corn oil by gavage at doses of 0, 7.5, 15, 30, 60, or 120 mg/kg, 5 days per week, for 14 weeks. All rats survived to the end of the study. Mean body weights of 30, 60, and 120 mg/kg males were significantly less than those of the vehicle controls. The only clinical finding attributed to 2,4-hexadienal administration was hypersalivation in 30 and 120 mg/kg males and females. The incidences of forestomach hyperplasia and nasal olfactory atrophy or necrosis were significantly increased in 120 mg/kg rats. Nasal lesions occurred in most 120 mg/kg male rats. 14-WEEK STUDY IN MICE: Groups of 10 male and 10 female mice were administered 2,4-hexadienal in corn oil by gavage at doses of 0, 7.5, 15, 30, 60, or 120 mg/kg, 5 days per week, for 14 weeks. No deaths were attributed to administration of 2,4-hexadienal. Mean body weights of males and females were similar to those of the vehicle controls throughout the study. Clinical findings included salivation and anal wetness in males and females. Kidney weights of 60 and 120 mg/kg males and liver weights of 60 mg/kg males and females were significantly greater than those of the vehicle controls. The incidences of forestomach hyperplasia and/or nasal olfactory atrophy or necrosis were significantly increased in 120 mg/kg mice. 2-YEAR STUDY IN RATS: Groups of 50 male and 50 female rats were administered 2,4-hexadienal in corn oil by gavage at doses of 0, 22.5, 45, or 90 mg/kg, 5 days per week, for up to 105 weeks. Survival of all dosed groups of rats was similar to that of the vehicle control groups. The mean body weights of 90 mg/kg males were generally less than those of the vehicle controls throughout the study. The incidences of squamous cell papilloma of the forestomach occurred with positive trends in male and female rats. This neoplasm was found in 58% of males and 34% of females in the 90 mg/kg groups. In the forestomach of male rats, papilloma multiplicity was increased in the 90 mg/kg group, and squamous cell carcinomas were found in one 45 mg/kg male and two 90 mg/kg males. Epithelial hyperplasia of the forestomach occurred in most 45 and 90 mg/kg rats. 2-YEAR STUDY IN MICE: Groups of 50 male and 50 female mice were administered 2,4-hexadienal in corn oil by gavage at doses of 0, 30, 60, or 120 mg/kg, 5 days per week, for up to 105 weeks. Survival of dosed mice was similar to that of the vehicle controls. The mean body weights of all dosed groups were generally similar to those of the vehicle controls throughout the study. The incidences of squamous cell papilloma of the forestomach occurred with positive trends in male and female mice; squamous cell carcinomas were present in 120 mg/kg males and females. Epithelial hyperplasia of the forestomach occurred in many 120 mg/kg mice. Two 120 mg/kg males had uncommon squamous cell carcinoma of the oral cavity (tongue). GENETIC TOXICOLOGY: 2,4-Hexadienal was mutagenic in S. typhimurium strain TA100 with and without induced hamster or rat liver enzymes; no mutagenic activity was detected with strains TA1535 or TA98, with or without S9. Results of bone marrow tests in male rats and male mice given intraperitoneal injections of 2,4-hexadienal showed a small increase in the induction of micronucleated erythrocytes. However, neither test was repeated, and the test results were judged to be inconclusive. Results of peripheral blood micronucleus tests in male and female mice treated with 2,4-hexadienal by gavage for 14 weeks were negative. CONCLUSIONS: Under the conditions of these 2-year gavage studies, there was clear evidence of carcinogenic activity* of 2,4-hexadienal in male and female F344/N rats and male and female B6C3F1 mice based on increased incidences of squamous cell neoplasms of the forestomach. The occurrence of squamous cell carcinoma of the oral cavity (tongue) in male B6C3F1 mice may have been related to the administration of 2,4-hexadienal. Hyperplasia of the forestomach in male and female rats and mice was associated with administration of 2,4-hexadienal.

2,4-Hexadeinal has been tentatively identified as a plant volatile(1).

2,4-Hexadienal's production and use as a food additive and chemical intermediate(1) may result in its release to the environment through various waste streams.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 17(SRC), determined from a structure estimation method(2), indicates that 2,4-hexadienal is expected to have very high mobility in soil(SRC). Volatilization of 2,4-hexadienal from moist soil surfaces may be an important fate process(SRC) given a Henry's Law constant of 9.78X10-6 atm-cu m/mole(3). The potential for volatilization of 2,4-hexadienal from dry soil surfaces may exist based upon an estimated vapor pressure of 4.8 mm Hg(SRC), determined from a fragment constant method(4).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 17(SRC), determined from a structure estimation method(2), indicates that 2,4-hexadienal is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces may be expected(3) based upon a Henry's Law constant of 9.78X10-6 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3.8 and 30.6 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 2(SRC), from an estimated log Kow of 1.37(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low.|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,4-hexadienal, which has an estimated vapor pressure of 4.8 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor. Vapor-phase 2,4-hexadienal is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 5.9 hours(SRC), calculated from its rate constant of 6.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). The rate constant for the vapor-phase reaction of 2,4-hexadienal with ozone has been estimated as 8.4X10-16 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3), corresponding to an atmospheric half-life of about 1.4 days at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(4).

The rate constant for the vapor-phase reaction of 2,4-hexadienal with photochemically-produced hydroxyl radicals has been estimated as 6.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 5.9 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of 2,4-hexadienal with ozone has been estimated as 8.4X10-16 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(1). This corresponds to an atmospheric half-life of about 1.4 days at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2). 2,4-Hexadienal is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(3) nor to directly photolyze due to the lack of absorption in the environmental UV spectrum (>290 nm).

An estimated BCF of 2.3 was calculated for 2,4-hexadienal(SRC), using a estimated log Kow of 1.4(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC), provided the compound is not altered physically or chemically once released into the environment.

Using a structure estimation method based on molecular connectivity indices(1), the Koc for 2,4-hexadienal can be estimated to be 17(SRC). According to a classification scheme(2), this estimated Koc value suggests that 2,4-hexadienal is expected to have very high mobility in soil.

The Henry's Law constant for 2,4-hexadienal is 9.78X10-6 atm-cu m/mole (1). This Henry's Law constant indicates that 2,4-hexadienal is expected to volatilize from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 3.8 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 30 days(SRC). 2,4-Hexadienal's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of 2,4-hexadienal from dry soil surfaces may exist(SRC) based upon an estimated vapor pressure of 4.8 mm Hg(SRC), determined from a fragment constant method(3).

2,4-Hexadeinal has been identified as a volatile in Korean salt-fermented fish paste with concentrations of 491 and 1,570 ng/g reported in anchovey and big-eyed herring, respectively; it was not found in hair tail viscera nor shrimp pastes(1). The compound has been identified as a meat flavor volatile in mutton and beef, arising during the cooking process via the autooxidation of the appropriate polyunsaturated fatty acid(2).

Occupational exposure to 2,4-hexadienal may occur through inhalation and dermal contact with this compound at workplaces where 2,4-hexadienal is produced or used. Monitoring data indicate that the general population may be exposed to 2,4-hexadienal via inhalation or ingestion of food. (SRC)

...Mechanistic studies indicated that the forestomach carcinogenesis in rats and mice may be due to depletion of glutathione as a result of oxidative stress induced by /2,4-Hexadienal/.

2,4-hexadienal

2,4-Hexadienal, (2E,4E)-: ACTIVE

Food additives -> Flavoring Agents|Flavoring Agents -> JECFA Flavorings Index|Fatty Acyls [FA] -> Fatty aldehydes [FA06]

Flavoring Agents