3-Methylbenzaldehyde

199 °C

199.00 °C. @ 760.00 mm Hg

Warning

H319 (98.5%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

P264+P265, P280, P305+P351+P338, and P337+P317 (click each P-code to see the statement)

Aggregated GHS information provided per 272 reports by companies from 9 notifications to the ECHA C&L Inventory.

Chemical: Benzaldehyde, 3-methyl-

Commission Regulation (EC) No 1565/2000 (Repealed by Com. Implementing Reg. (EU) No 872/2012)

Benzaldehyde, 3-methyl-: Does not have an individual approval but may be used under an appropriate group standard

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.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 53(SRC), determined from a structure estimation method(2), indicates that 3-methylbenzaldehyde is expected to have high mobility in soil(SRC). Volatilization of 3-methylbenzaldehyde from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 3.0X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(3). 3-Methylbenzaldehyde is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 0.38 mm Hg(SRC), determined from a fragment constant method(4). Based on limited information, 3-methylbenzaldehyde is expected to biodegrade in soil(SRC). A Pseudomonas strain was able to utilize 3-methylbenzaldehyde as the sole carbon source(5); a yeast strain grown with both this compound and either sucrose or pyruvate biodegraded 3-methylbenzaldehyde to the respective aromatic carbinol or alcohol(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 53(SRC), determined from a structure estimation method(2), indicates that 3-methylbenzaldehyde is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 3.0X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 1.5 and 14 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 11(SRC), from an estimated log Kow of 2.26(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). 3-Methylbenzaldehyde is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). Based on limited data, biodegradation of 3-methylbenzaldehyde will take place in water. A Pseudomonas strain was able to utilize 3-methylbenzaldehyde as the sole carbon source(8); a yeast strain grown with both this compound and either sucrose or pyruvate biodegraded 3-methylbenzaldehyde to the respective aromatic carbinol or alcohol(9).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 3-methylbenzaldehyde, which has an estimated vapor pressure of 0.38 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 3-methylbenzaldehyde 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 23 hrs(SRC), calculated from its rate constant of 1.7X10-11 cu cm/molecule-sec at 25 °C(3). The reactivity of 3-methylbenzaldehyde (1 ppm) with NOx (0.5 ppm) in light was measured in a smog chamber as 2.36 ppb/min(4). 3-Methylbenzaldehyde contains chromophores that absorb at wavelengths >290 nm(5) and therefore may be susceptible to direct photolysis by sunlight(SRC).

3-Methylbenzaldehyde has been possibly identified in exhaust gases from gasoline engines, diesel engines and in diesel blowby(1). 3-Methylbenzaldehyde was found in highway tunnels in Tuscarora; light duty trucks emitted 0.067 mg/km traveled or 0.238 mg/L fuel used, heavy duty trucks emitted 1.062 mg/km traveled or 1.594 mg/L fuel used(2). 3-Methylbenzaldehyde was detected in the emissions from ten four-stroke lawn mower engines at 0.13% of total emissions(3). Fine aerosol emission rates of 3-methylbenzaldehyde from heavy-duty diesel trucks, noncatalyst-equipped and catalyst-equipped automobiles were 1.6, 3.5 and 0.53 ug/km, respectively(4). 3-Methylbenzaldehyde was not detected in road dust particles collected from paved streets in a residential area of Pasadena, CA in May 1988, was detected in brake lining particles at a concn of 0.11 ug/g of particle sample and in tire wear particles at a concn of 1.4 ug/g of particle sample(5). Operation of a four-stroke outboard motor resulted in the exhaust emission of 6.4 mg/10 min of 3-methylbenzaldehyde into the water(6).

3-Methylbenzaldehyde/4-methylbenzaldehyde was measured in the emissions of burnt wood at 12 and 27 mg/kg of pine and eucalyptus, but was not detected in the emissions of burnt oak(1).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 3-methylbenzaldehyde can be estimated to be 53(SRC). According to a classification scheme(2), this estimated Koc value suggests that 3-methylbenzaldehyde is expected to high mobility in soil.

URBAN/SUBURBAN: 3-Methylbenzaldehyde, analyzed in Athens, Greece, June to December 2000, was detected at Patission Street at concns of 2.4-3.9 ug/cu m(1). 3-Methylbenzaldehyde was detected in air from San Paulo, Brazil at 0.090-0.831 ppb in samples taken July 1988(2). 3-Methylbenzaldehyde was found at an avg concn of 0.24 ppb in Los Angeles(3).

RURAL/REMOTE: 3-Methylbenzaldehyde, analyzed outside of Athens, Greece, June to December 2000, was detected at Likovrisi at concns of 2.4-2.8 ug/cu m(1). 3-Methylbenzaldehyde was identified in forest air collected in the Southern Black Forest, Germany, at unreported concentrations(2).

SOURCE DOMINATED: A field monitoring study along a highway in Raleigh, NC in May 1983 detected 3-methylbenzaldehyde levels of 3.01-14.27 ppb; the primary source of the 3-methylbenzaldehyde was considered to be exhaust from cars and trucks(1).

The primary source of the 3-methylbenzaldehyde was considered to be exhaust from cars and trucks(1) and has been detected in exhaust from light duty trucks(2), heavy duty trucks(2), heavy-duty diesel trucks(3), noncatalyst-equipped and catalyst-equipped automobiles(3), four-stroke lawn mower engines(4) and four-stroke outboard motors(5). 3-Methylbenzaldehyde was also detected in brake lining particle samples and in tire wear particle samples(6).

PURE CULTURE: A Pseudomonas strain, isolated from soil, was able to utilize 3-methylbenzaldehyde as the sole carbon source, giving 0.22, 0.27, and 0.40 um O2 consumed/min/mg dry weight cells, for cells previously grown on m-xylene, p-xylene, and p-methylbenzyl alcohol, respectively(1). The rates of formation of aromatic carbinol and aromatic alcohol from a yeast culture grown in both 3-methylbenzaldehyde and sucrose are 0.45 and 0.87 g/L, respectively for a 1 hr incubation(2). The rates of formation of aromatic carbinol and aromatic alcohol from a yeast culture grown in both 3-methylbenzaldehyde and pyruvate are 1.35 and 0.20 g/L, respectively, for a 1 hr incubation(2).

An estimated BCF of 11 was calculated in fish for 3-methylbenzaldehyde(SRC), using an estimated log Kow of 2.26(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).

The Henry's Law constant for 3-methylbenzaldehyde is estimated as 3.0X10-5 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 3-methylbenzaldehyde 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 1.5 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 14 days(SRC). 3-Methylbenzaldehyde's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 3-Methylbenzaldehyde is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 0.38 mm Hg(SRC), determined from a fragment constant method(3).

/LABORATORY ANIMALS: Acute Exposure/ Tolualdehyde was a skin irritant in rabbits. ...Sensitization reactions were apparently induced in guinea-pigs. /Tolualdehydes/

/LABORATORY ANIMALS: Acute Exposure/ In rats, the acute oral and dermal toxicity were low ... /Tolualdehydes/

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ In rats, ... pituitary gland weight was reduced following repeated oral administration. /Tolualdehydes/

/GENOTOXICITY/ There was no evidence of mutagenicity in Ames bacterial tests. /Tolualdehydes/

The rate constant for the vapor-phase reaction of 3-methylbenzaldehyde with photochemically-produced hydroxyl radicals has been measured as 1.7X10-11 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 23 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The reactivity of 3-methylbenzaldehyde was measured using the smog chamber method where the aldehyde is irradiated in a mixture with nitric oxide and air; the reactivity of 1 ppm of 3-methylbenzaldehyde with 0.5 ppm of NOx was measured as 2.36 ppb/min(2). 3-Methylbenzaldehyde is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 3-Methylbenzaldehyde contains chromophores that absorb at wavelengths >290 nm(3) and therefore may be susceptible to direct photolysis by sunlight(SRC).

... m-Xylene (m-XYL) has been shown to alter cytochrome P-450 (CYP) activity in an organ- and isozyme-specific manner. The purpose of this work was to determine if the metabolism of m-XYL to the inhibitory metabolite m-tolualdehyde (m-ALD) is the cause of inhibition of CYP isozymes following in vivo inhalation exposure to m-XYL (100, 300 ppm), 3-methylbenzyl alcohol (3-MBA) (50, 100 ppm), or m-ALD (50, 100 ppm). A single 6-hr inhalation exposure of rats to m-XYL inhibited pulmonary CYPs 2B1, 2E1, and 4B1 in a dose-dependent manner. Inhalation of 3-MBA inhibited pulmonary CYPs 2B1 and 4B1 in a dose-dependent manner. m-ALD inhibited pulmonary CYPs 2B1 and 2E1 in a dose-dependent manner, while 4B1 activity was increased dose dependently. Nasal mucosa CYP 2B1 and 2E1 activity was inhibited following exposure to m-XYL dose dependently, 3-MBA inhibited nasal mucosa CYPs 2E1 and 4B1 dose dependently. CYPs 2B1, 2E1, and 4B1 were inhibited in a dose-dependent fashion following inhalation of m-ALD. Following high-performance liquid chromatography (HPLC) analysis, m-ALD was detected after in vivo exposure to m-XYL, m-ALD, and 3-MBA in a dose-dependent manner, with highest m-ALD levels in the nasal mucosa and lung. Alteration of cytochrome P-450 activity by m-XYL could result in increased or decreased toxicity, changing the metabolic profiles of xenobiotics in coexposure scenarios in an organ-specific manner.

p-Tolualdehyde was oxidized to p-toluic acid by resting cells of pseudomonas aeruginosa. Perillaldehyde dehydrogenase, isolated from soil pseudomonad, catalyzed the oxidn of m- & p-tolualdehyde but not o-tolualdehyde.

Aldehydes are readily oxidized to organic acids. Oxidation of aldehydes is catalyzed by aldehyde dehydrogenase, which has been found in the brain, erythrocytes, liver, kidney, heart, and placenta. /Aldehydes/