4-Methylbenzaldehyde

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.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 62(SRC), determined from a water solubility of 2,270 mg/L(2) and a regression-derived equation(3), indicates that 4-methylbenzaldehyde is expected to have high mobility in soil(SRC). Volatilization of 4-methylbenzaldehyde from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.7X10-5 atm-cu m/mole(SRC), derived from its vapor pressure, 0.25 mm Hg(4), and its water solubility(2). 4-Methylbenzaldehyde is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). Based on limited information, 4-methylbenzaldehyde is expected to biodegrade in soil(SRC). A Pseudomonas strain was able to utilize 4-methylbenzaldehyde as the sole carbon source(5); a yeast strain grown with both this compound and either sucrose or pyruvate biodegraded 4-methylbenzaldehyde to the respective aromatic carbinol or alcohol(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 62(SRC), determined from a water solubility of 2,270 mg/L(2) and a regression-derived equation(3), indicates that 4-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 1.7X10-5 atm-cu m/mole(SRC), derived from its vapor pressure, 0.25 mm Hg(4), and its water solubility(2). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2.4 and 21 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 8(SRC), from its water solubility(2) and a regression-derived equation(3), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Based on limited data, biodegradation of 4-methylbenzaldehyde will take place in water(SRC). A Pseudomonas strain was able to utilize 4-methylbenzaldehyde as the sole carbon source(6); a yeast strain grown with both this compound and either sucrose or pyruvate biodegraded 4-methylbenzaldehyde to the respective aromatic carbinol or alcohol(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 4-methylbenzaldehyde, which has a vapor pressure of 0.25 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 4-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 21 hrs(SRC), calculated from its rate constant of 1.8X10-11 cu cm/molecule-sec at 25 °C(3). The reactivity of 4-methylbenzaldehyde (1 ppm) with NOx (0.5 ppm) in light was measured in a smog chamber as 1.78 ppb/min(4). 4-Methylbenzaldehyde contains chromophores that absorb at wavelengths >290 nm(5) and therefore may be susceptible to direct photolysis by sunlight(SRC).

Operation of a four-stroke outboard motor resulted in the exhaust emission of 2.8 mg/10 min of 4-methylbenzaldehyde into the water(1). 4-Methylbenzaldehyde was emitted from a fireplace burning jack pine, cedar, red oak, and green ash wood at concns of 0.114-0.475 g/kg(2). 4-Methylbenzaldehyde was emitted from non-catalyst and catalyst automobiles at 7.7 and 1.7 ug/km, respectively(3). Heavy-duty diesel trucks emitted 2.3 ug 4-methylbenzaldehyde/km(3). 4-Methylbenzaldehyde was identified in rush hour traffic air samples taken at the Oakland-San Francisco Bay Bridge toll plaza 4/23/2001, 5-7 pm, 4/24/2001, 6-10 am, and 3-7 pm at concns of 0.018-0.023 ug/cu m(4). 4-Methylbenzaldehyde was found in highway tunnels in Tuscarora; light duty trucks emitted 0.023 mg/km traveled or 0.305 mg/L fuel used, heavy duty trucks emitted 0.335 mg/km traveled or 0.962 mg/L fuel used(5). 4-Methylbenzaldehyde emissions from an automobile running on Swedish environmental classified diesel fuel were 0.6 mg/km and the same automobile running on European program emissions fuel were also 0.6 mg/km(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).

The Koc of 4-methylbenzaldehyde is estimated as 62(SRC), using a water solubility of 2,270 mg/L(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 4-methylbenzaldehyde is expected to have high mobility in soil.

P-Tolualdehyde (CAS # 104-87-0) was evaluated for acute oral toxicity. The test substance was administered to 10 rats (sex and strain not indicated) at a dosage range of 200-3200 mg/kg. No unusual clinical signs were observed, except for evidence of slight toxicity. Mortality data were not provided, except for time of death (within 1 day). The LD50 was determined to be 1600 mg/kg.

P-Tolualdehyde (CAS # 104-87-0) was evaluated for acute inhalation toxicity by exposing 6 rats (sex and strain not indicated) to a single six-hour inhalation exposure of 373 and 444 ppm. No mortality occurred. The rats gained weight normally and there were no unusual clinical signs other than irritation.

P-Tolualdehyde (CAS # 104-87-0) was evaluated for subchronic oral toxicity. The test substance was administered by gavage to 5/rats/dose (sex and strain not indicated) at dosage levels of 100 or 1000 mg/kg/day for a total of 12 doses over 17 days. Feed consumption and weight gain were normal. Hematology, clinical chemistry, liver and kidney weights, and gross and histopathological findings were normal.

P-Tolualdehyde (CAS # 104-87-0) was evaluated for subchronic dermal toxicity. The test substance was administered (dosage not indicated) to the clipped backs of guinea pigs (number, sex, and strain not indicated) and repeated applications produced a slight exacerbation of the irritation response seen from a single application.

For more TSCA Test Submissions (Complete) data for 4-METHYLBENZALDEHYDE (8 total), please visit the HSDB record page.

URBAN/SUBURBAN: 4-Methylbenzaldehyde, analyzed in Athens, Greece, June to December 2000, was detected at Patission Street at concns of 1.2-5.9 ug/cu m(1). 4-Methylbenzaldehyde was detected at average concns of 0.032-0.131 ug/cu m in Rio de Janeiro, Brazil Oct 1999 to Nov 2000(2). 4-Methylbenzaldehyde was analyzed but not detected in samples taken at the top of an 11 story building on the campus of Hong Kong University Science and Technology(3).

RURAL/REMOTE: 4-Methylbenzaldehyde was identified in forest air collected in the Southern Black Forest, Germany, at unreported concentrations(1).

SOURCE DOMINATED: 4-Methylbenzaldehyde was analyzed but not detected in kitchen exhaust(1).

/SIGNS AND SYMPTOMS/ The mucus membranes of the nasal and oral passages and the upper respiratory tract are affected, producing a burning sensation, ... bronchial constriction, choking, and coughing. The eyes tear, and a burning sensation is noted on the skin of the face. /Aldehydes/

/SIGNS AND SYMPTOMS/ No evidence of skin sensitization was found in volunteers treated with dilute solutions. /Tolualdehydes/

4-Methylbenzaldehyde's production and use in perfumes, as a pharmaceutical and dyestuff intermediate, and as a flavoring agent(1) may result in its release to the environment through various waste streams(SRC). Exhaust from outboard motors(2), automobiles and trucks(3), and emissions from fireplaces(4) contain 4-methylbenzaldehyde.

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329. Effective date 9/30/91; Reporting date: 11/27/91.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Benzaldehyde, 4-methyl- is included on this list. Effective date 9/30/91; Sunset date: 6/30/98.