Pentacosane

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for firefighters: Wear self contained breathing apparatus for fire fighting if necessary.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Avoid dust formation. Avoid breathing vapors, mist or gas. Environmental precautions: Do not let product enter drains. Methods and materials for containment and cleaning up: Sweep up and shovel. Keep in suitable, closed containers for disposal.

SMALL SPILLS AND LEAKAGE: If you spill this chemical, use absorbent paper to pick up all liquid spill material. Your contaminated clothing and absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with alcohol followed by washing with a strong soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Offer surplus and non-recyclable solutions to a licensed disposal company; Contaminated packaging: Dispose of as unused product.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Avoid dust formation. Avoid breathing vapors, mist or gas. Environmental precautions: Do not let product enter drains.

Precautions for safe handling: Provide appropriate exhaust ventilation at places where dust is formed. Normal measures for preventive fire protection.

Appropriate engineering controls: General industrial hygiene practice.

Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

For more Preventive Measures (Complete) data for n-Pentacosane (6 total), please visit the HSDB record page.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter.

Eye/face protection: Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).

Skin protection: Handle with gloves.

Body Protection: Choose body protection in relation to its type, to the concentration and amount of dangerous substances, and to the specific work-place.

Respiratory protection: Respiratory protection is not required. Where protection from nuisance levels of dusts are desired, use type N95 (US) or type P1 (EN 143) dust masks. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1.2X10+7(SRC), determined from a structure estimation method(2), indicates that pentacosane is expected to be immobile in soil(SRC). Volatilization of pentacosane from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 370 atm-cu m/mole(SRC), using a fragment constant estimation method(3). However, adsorption to soil is expected to attenuate volatilization(SRC). Pentacosane is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.51X10-6 mm Hg at 25 °C(4). Pentacosane, present as a component of petroleum oil, was degraded by 4 of 5 bacterial strains with certain nitrogen sources; consumption ranged from 11 to 92% after 10 days(5), indicating that biodegradation is an important environmental fate process under certain conditions in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1.2X10+7(SRC), determined from a structure estimation method(2), indicates that pentacosane is 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 370 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 1.9 hours and 7.4 days, respectively(SRC). However, adsorption to ssediment and suspended solids is expected to attenuate volatilization(SRC). The estimated volatilization half-life from a model pond is greater than 2 years if adsorption is considered(5). According to a classification scheme(6), an estimated BCF of 23(SRC), from an estimated log Kow of 12.62(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Pentacosane, present as a component of petroleum oil, was degraded by 4 of 5 bacterial strains with certain nitrogen sources; consumption ranged from 11 to 92% after 10 days(5), indicating that biodegradation may be an important environmental fate process under certain conditions in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), pentacosane, which has a vapor pressure of 1.51X10-6 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase pentacosane 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 12 hours(SRC), calculated from its rate constant of 3.23X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase pentacosane may be removed from the air by wet and dry deposition(SRC). Pentacosane does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

IDENTIFICATION AND USE: Pentacosane is a solid n-alkane containing 25 carbon atoms (C25). Solid n-alkanes (paraffin waxes) are used in a variety of applications: as feeds for cracking them to gasoline blendstock materials, oxidation, and chlorination reactions. HUMAN EXPOSURE AND TOXICITY: There are no data available. ANIMAL STUDIES: A homologous series of n-alkanes ranging from n-C12-n-C31 was found in all samples of bovine tissues.

Pentacosane detections in plants used in food and medicinal applications(1). /Pentacosane/[Table#8375]

n-Pentacosane detections in plants used in food and medicinal applications(1).

Pentacosane was identified in the extract of some plastic materials from Concon, Chile(1); it was not detected in the surface extract of new plastic bags, but was detected in plastic roadside litter and landfill trash at concentrations of 14.9 and 10.4 ug/g, respectively; it was not detected in the particulate matter of open burn smoke from new plastic bags, but was detected in the particulate matter of open burn smoke from plastic roadside litter and landfill trash, at concentrations of 24.4 and 13.5 ng/mg, respectively; pentacosane was not detected in the surface extract of new plastic bags from the United States but was detected in the open burn smoke of new plastic bags from the United States at a concentration of 24.7 ng/mg(1). Average concentrations of pentacosane emitted as a result of Chinese cooking styles were reported as 292, 303, 102, and 205 ng/mg, for Cantonese style, Sichuan style, Dongbei style, and Hunan style cooking, respectively(2).

The Koc of pentacosane is estimated as 1.2X10+7(SRC), using an estimated log Kow of 12.62(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that pentacosane is expected to be immobile in soil.

URBAN/SUBURBAN: In 2002, pentacosane was detected in the gas-phase and the particulate-phase of urban and industrial air samples from Prato, Italy, at average concentrations of approximately 8.5 and 15.5 ng/cu m, respectively(1). Pentacosane was detected in the particulate matter of ambient urban air sampled daily from January 2003 through December 2004 in Augsburg, Germany; average concentrations reported for spring, summer, fall and winter were 5.83, 3.82, 8.17, and 12.04 ng/cu m, respectively(2). During late fall and winter seasons pentacosane was monitored in the particulate matter of ambient atmospheres in urban areas of Corvallis OR, Guangzhou China, Beijing China, and Taiyuan China, with reported concentrations of 1.1, 62.7, 128.1, and 58.2 ng/cu m, respectively(3).

SOURCE DOMINATED: Pentacosane was detected in the particle phase of tailpipe emissions from catalyst equipped gasoline powered motor vehicles at a concentration of 2.7 ug/km; and in the gas and particle phase of tailpipe emissions from non-catalyst equipped gasoline powered motor vehicles at concentrations of 14.3 and 489 ug/km, respectively; it was also detected in the gasoline at 1.7 ug/g(1). Concentrations of various compounds including alkanes were reported near a highway in Raleigh, NC with an annual average daily traffic count of approximately 125,000 vehicles. High volume PM2.5 air samples were collected at two locations, one approximately 10 meters (near) and the other 275 meters perpendicular (far) from the road(2). Mean (range) pentacosane concentrations were 460 (150-1100) and 370 (120-1350) pg/cu m at the near and far sites, respectively(2). Pentacosane was detected in the particulate phase of emissions from light-duty vehicles using diesel fuel at concentrations ranging from 5.29 to 15.88 ug/mg for vehicle with an emission control device and 132.4 ug/mg for the vehicle without an emission control device(3). Field sampling, conducted during June-July 2005 and January 2006, of particulate matter collected roadside of an interstate highway in Atlanta GA, 400 meters away from the freeway at the Georgia Tech campus, and at a rural site in Yorkville GA, had pentacosane concentrations of approximately 7.7, 5.0, and 3.1 ng/cu m, respectively(4).

Barnacle samples collected from five locations in the Arabian Gulf had concentrations of pentacosane ranging from not detected to 970 ng/g(1). Catfish samples collected from seven locations in the Arabian Gulf had concentrations of octadecane ranging from not detected to 126 ng/g(2).

PURE CULTURE: Using 5 different marine bacterial strains and 4 different nitrogen sources, biodegradation of petroleum oil was examined under aerobic conditions at 26 °C for 10 days; pentacosane, present as a component of the petroleum oil, was not degraded by 1 of the 5 strains but was degraded by 4 of 5 bacterial strains with certain nitrogen sources, consumption ranged from 11 to 92%(1).

SEDIMENTS: Pentacosane was detected in sediment samples from 14 sites along the Shinano River in Japan, from Nov 2005 to April 2006, at concentrations ranging from 0.8 to 14 ng/g dry weight(1).

SOIL: During winter 2002 soil and sand samples, from six locations in the Riyadh metropolitan area of Saudi Arabia, were examined for extractable organic matter; pentacosane was detected at relative concentrations between 0.01 to 1.20% (of total extractable organic matter) at all six locations(1).