(1-Methylethyl)-1,1'-biphenyl

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

A closed process system is used for production which limits occupational exposure. /SURE SOL 250, 6% di- and triisopropyl/

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.

LC50 Bluegill sunfish static 4 ppm 96hr /Wemcol, 1% diisopropyl/

LC50 Rainbow trout 2.5 ppm 96 hr static /Wemcol, 1% diisopropyl/

LC50 Flagfish (adult) > 0.75 ppm 96hr flow-through /Wemcol, 1% diisopropyl/

LC50 Flagfish (fry) 0.28 ppm 96 hr flow-through /Wemcol, 1% diisopropyl/

For more Ecotoxicity Values (Complete) data for ISOPROPYLBIPHENYL (6 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 16,000(SRC), determined from a measured log Kow(2) and a recommended regression-derived equation(3), indicates that isopropylbiphenyl will be immobile in soil(SRC). This compound may rapidly biodegrade under aerobic conditions in soil(SRC). More than 80% of the added isopropylbiphenyl biodegraded aerobically within 48 hours using sediment-water samples in the River Die-Away Test(4). In sewage sludge tests, isopropylbiphenyl was biodegraded 60% in 24 hours and completely biodegraded within one week(4). Volatilization of isopropylbiphenyl may be important from moist soil surfaces(SRC) given an estimated Henry's Law constant of 2.1X10-4 atm-cu m/mole(SRC), determined from experimental values for vapor pressure(2) and water solubility(2), but should not be significant from dry soil surfaces(SRC) based on an experimental vapor pressure of 5X10-4 mm Hg(2).

AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 16,000(SRC), determined from a measured log Kow(2) and a recommended regression-derived equation(1), indicates that isopropylbiphenyl should adsorb to suspended solids and sediment in water(SRC). This compound should rapidly biodegrade under aerobic conditions(SRC). More than 80% of the added isopropylbiphenyl biodegraded aerobically within 48 hours using sediment-water samples in the River Die-Away Test(3). In sewage sludge tests, isopropylbiphenyl was biodegraded 60% in 24 hours and completely biodegraded within one week(3). Isopropylbiphenyl may volatilize from water surfaces based on an estimated Henry's Law constant of 2.1X10-4 atm-cu m/mole(SRC), determined from experimental values for vapor pressure(2) and water solubility(2). Estimated half-lives for a model river and model lake are 10 hours and 7 days, respectively(1,SRC). An estimated BCF value of 5300(1,SRC), from a measured log Kow(2), suggests that isopropylbiphenyl will bioconcentrate in aquatic organisms(SRC), according to a recommended classification scheme(4).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), isopropylbiphenyl, which has a measured vapor pressure of 5X10-4 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase isopropylbiphenyl 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 about 40 hours(3,SRC). Particulate-phase isopropylbiphenyl may be physically removed from the air by dry deposition(SRC).

IDENTIFICATION AND USE: Isopropyl biphenyl is a white solution, soluble in water. It is used in carbonless-copy paper systems, replaces PCBs in capacitors, and heat transfer fluids. It is used a s a solvent in high voltage capacitors, and as a veterinary medicine to control inflammation. This chemical improves wear properties, and provides radiation resistance when used in lubricants. It is used as a solvent. HUMAN EXPOSURE AND TOXICITY: Complaints of an unpleasant smell, headaches, irritation, fatigue and redness of the face and eyes were reported in female office workers handling self- copying paper forms. The smell was attributed to the release of isopropyl biphenyl solvent. Office workers indicated only eye, and respiratory tract irritation caused by carbonless copy paper containing this chemical was most often associated with symptoms. Again, CPP treated with desentizing ink were associated with skin irritation. It is a mild irritant on abraded skin, slight irritant on intact skin. ANIMAL STUDIES: When administered to rats orally this chemical for 10 to 15 days caused neutropenia, lymphocytosis, and hypoproteinemia, dystrophy of the liver and kidneys, hyperplasia of the spleen and hypertrophy of myocardial fibers. Inhalation of this compound by rats caused grooming and slight depression during and immediately after exposure. Necropsy showed no gross anomalies.

The Koc of isopropylbiphenyl is estimated as approximately 16000(SRC), using a measured log Kow of 5.20(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that isopropylbiphenyl will be immobile in soil(SRC).

Isopropylbiphenyl (SUN X-783-1) was examined for mutagenic activity in Salmonella typhimurium tester strains TA1535, TA1537, TA1538, TA98, TA100, and in Saccharomyces cerevisiae D4 with and without metabolic activation provided by Aroclor-induced rat liver S9 fraction. The test article was not mutagenic when administered at concentrations from 0.001 to 5 ul/plate in the plate incorporation assay, with or without activation. In a preliminary toxicity test, toxic effects at 5 ul/plate were reported.

Isopropylbiphenyl (SUN X-489-17) was examined for mutagenic activity in Salmonella typhimurium tester strains TA1535, TA1537, TA1538, TA98, TA100 and in Saccharomyces cerevisiae D4 with and without metabolic activation provided by Aroclor-induced rat liver S9 fraction. The test article was not mutagenic when administered at concentrations ranging from 0.01 to 5 ul/plate by the plate incorporation method, in the presence or absence of activation. The investigators reported that isopropylbiphenyl was toxic to cells at 5 ul/plate in a preliminary toxicity screen.

Isopropylbiphenyl (Sun Capacitor Oil X489-17E) was examined for mutagenic activity in Salmonella typhimurium tester strains TA1535, TA100, TA1538, TA98, TA1537 and TA1978 with and without metabolic activation provided by rat liver homogenate. The test article was not mutagenic when 1 to 10 ul/plate of an unspecified concentrated solution was administered in the plate incorporation assay either with or without activation. Additionally, 10 and 20 ul of the unspecified solution was not mutagenic in spot tests without activation. The investigators reported that the concentrated solution was not toxic to cells.

Acute oral toxicity was evaluated in groups of 5 (male and female) SASCO rats administered single doses of undiluted isopropyl biphenyl by oral gavage at levels of 2.00, 3.17, 5.024, 7.962 and 12.62 g/kg body weight. Mortality was observed in 4 animals in the 5.024 g/kg dose group, in 3 animals in the 7.962 g/kg dose group, and in all rats in the 12.62 g/kg dose group; the LD50 value was calculated to 5.26 g/kg with a confidence interval of 3.93-7.04 g/kg by the method of C.S. Weil. Clinical observations, between 1 and 72 hours, included piloerection, ptosis, weakness, hypersensitivity, roughened pelage and emaciation. Gross necropsy in animals that died revealed congestion of the lungs, liver, kidneys, adrenal glands and gastrointestinal tract and hemorrhage in the stomach. Gross necropsy observations of sacrificed animals were not reported.

For more TSCA Test Submissions (Complete) data for ISOPROPYLBIPHENYL (9 total), please visit the HSDB record page.

Complaints of an unpleasent smell, headaches, irritation, fatigue and redness of the face and eyes were reported in 9 out of 13 female office workers handling self-copying paper forms. The smell was attributed to the release of isopropylbiphenyl solvent.

Conclusions of 5 papers on the subject: Studies in 80 office workers indicated only eye and respiratory tract irritation caused by carbonless copy paper (CCP). Papers treated with desensitizing ink were statistically associated with skin irritation. 273 paper samples were studied, 190 of which were carbonless. Paper containing monoisopropylbiphenyl was most often associated with symptoms. Again, CPP treated with desentizing ink were associated with skin irritation. Environmental conditions were studied. No correlations were found between airborne solvent concentrations from CPP and the occurrence of irritative symptoms. Formaldehyde, glutaraldehyde and the organic solvents in which the color formers are dissolved were studied under standard contitions. The emission of aldehydes from CPP is too low to cause the irritative symptoms. The highest emission was of kerosene, which could not be related to the symptoms. ...

More than 80% of the added isopropylbiphenyl biodegraded aerobically within 48 hr in a sediment-water sample using the River Die-Away Test(1). In sewage sludge tests, isopropylbiphenyl was biodegraded 60% in 24 hours and completely biodegraded within one week(1).

An estimated BCF value of 5300 was calculated for isopropylbiphenyl(SRC), using a measured log Kow of 5.20(1,SRC) and a recommended regression-derived equation(2). According to a recommended classification scheme(3), this BCF value suggests that bioconcentration in aquatic organisms will be very high(SRC).

Flagfish exposed to 3.51 ppb for 28 days had a bioconcentration factor of 2896 while the same fish exposed to 24.1 ppb for 28 days had a bioconcentration factor of 10,790 /Wemcol, 1% diisopropyl/

The Henry's Law constant for isopropylbiphenyl is estimated as 2.1X10-4 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 5X10-4 mm Hg(1), and water solubility, 0.6 mg/l(1). This value indicates that isopropylbiphenyl will volatilize from water surfaces(2,SRC). 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) is estimated as approximately 10 hours(2,SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec) is estimated as approximately 7 days(3,SRC). Volatilization from moist soil surfaces is likely given this compound's estimated Henry's Law constant(1,SRC), but not from dry soil surfaces(SRC), based on isopropylbiphenyl's measured vapor pressure(1).

WHEN ADMIN ORALLY TO RATS, THE LD50 VALUE OF ISOPROPYLDIPHENYL WAS 8.5 G/KG. WHEN ADMIN AT 800 MG/KG/DAY FOR 10-15 DAYS, ISOPROPYLDIPHENYL CAUSED NEUTROPENIA, LYMPHOCYTOSIS, HYPOPROTEINEMIA, DYSTROPHY OF THE LIVER & KIDNEYS, HYPERPLASIA IN THE SPLEEN, & HYPERTROPHY IN MYOCARDIAL FIBERS.

Inhalation of 20.8 mg/l by 10 rats for 1 hr at 18-20 °C produced no deaths. Grooming and slight depression were observed during and immediately following exposure. Autopsy revealed no gross anomalies. /SURE SOL 250, 5% di- and triisophenyl/

Inhalation of 0.99 g/cu m by 9 male and 9 female rats for 1 hr produced no deaths in 14 days. /SURE SOL 250, 5% di- and triisophenyl/

Inhalation of 15.86 g/cu m by male and female rats for 1 hr resulted in the death of 12/12 animals by the third day. Lungs and trachea showed acute necrotizing tracheobronchitis, pulmonary congestion and bronchopneumonia. /SURE SOL 250, 5% di- and triisophenyl/

In a 28-day pilot feeding study with rats using various concentrations, there was no indication of adverse effects at levels as high as 0.1%. /Wemcol, 1% diisopropyl/