Isodecyl diphenyl phosphate

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.

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.

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. (NTP, 1992)

LC50 Lepomis macrochirus 6700 ppm/96 hr, static bioassay in fresh water at 23 °C, mild aeration applied after 24 hr.

LC50 Menidia beryllina 1400 ppm/96 hr, static bioassay in synthetic seawater at 23 °C, mild aeration applied after 24 hr.

TERRESTRIAL FATE: Biodegradation is expected to be the dominant fate process of isodecyl diphenyl phosphate in soil(SRC); a screening test exhibited an aerobic half-life of about 11 days or less in natural waters(2). Based on analogy to triphenyl phosphate, aqueous hydrolysis may aid in soil degradation for isodecyl diphenyl phosphate especially under alkaline conditions (half-lives of 0.23 to 7.5 days at pH 9.5 to pH 8.2 for triphenyl phosphate)(1,SRC). Based on an estimated Koc of 21,695, isodecyl diphenyl phosphate should be immobile in soil and adsorption should take place(SRC).

AQUATIC FATE: Isodecyl diphenyl phosphate is expected to slowly volatilize from water based on a low Henry's Law constant(SRC). Biodegradation is an important removal process in aerobic waters with an aerobic half-life of about 11 days or less(1,3). However, biodegradation in benthic sediments is unclear(1). No hydrolysis data were located for isodecyl diphenyl phosphate; however, phosphate esters are generally resistant to hydrolysis in neutral or acid waters (pH 5-7)(2). Aqueous hydrolysis may be an important degradative pathway of isodecyl diphenyl phosphate in the environment under mildly alkaline conditions (pH 9)(1). Half-lives of the first hydrolysis step for triphenyl phosphate have been measured to range from 0.23 to 7.5 days at pH 9.5 to pH 8.2, respectively(1,2). An estimated Koc of 21,695 suggests that adsorption from the water column to sediment and suspended material may be an important fate process for isodecyl diphenyl phosphate in aquatic systems(1-3,SRC). Bioconcentration in aquatic organisms may be important(1,SRC).

ATMOSPHERIC FATE: Based on an estimated vapor pressure of 1.6X10-5 mm Hg at 25 °C(2), isodecyl diphenyl phosphate should exist in the particulate- and vapor-phases in the ambient atmosphere(3). Vapor-phase isodecyl diphenyl phosphate is rapidly degraded in the ambient atmosphere by reaction with photochemically formed hydroxyl radicals; the half-life for this reaction in air can be estimated to be about 8.8 hrs(1,SRC). Particulate-phase isodecyl diphenyl phosphate may be susceptible to wet and dry deposition(SRC).

Based upon a measured log Kow of 5.44(1), the Koc for isodecyl diphenyl phosphate can be estimated to be about 21,695 from a regression derived equation(2). According to a suggested classification scheme(3), isodecyl diphenyl phosphate should be immobile in soil and sediment. The low water solubility of 0.75 mg/l at 25 °C(1) and high Koc value suggest that adsorption to soil and sediment may be an important fate process for isodecyl diphenyl phosphate(4,SRC).

Isodecyl diphenyl phosphate and other aryl phosphates are released during production to soil via land disposal of solid or semi-solid wastes(1). Isodecyl diphenyl phosphate may also be released to the environment through processing and use applications; furthermore, release via use applications are expected to be more than from production(1). Isodecyl diphenyl phosphate may volatilize from plastic items where it is used as a plasticizer, it may leak from hydraulic fluids, and it may be released from lubricants where it is used as an additive(1-2). Isodecyl diphenyl phosphate may be released from plastics that are exposed to water in piping, it may leach from landfills, and it may be released in waste water effluents resulting from production and use(1-2).

The ultimate biodegradation of isodecyl diphenyl phosphate, initial concn of 19 ppm, was observed to be 13.5, 63.3, and 68.4% of theoretical CO2 evolution in a CO2-evolution screening study using acclimated seed (14 day acclimation period) over an incubation period of 7, 28, and 35 days, respectively. Isodecyl diphenyl phosphate biodegraded 20 to 54% with an addition rate of 13 to 3 1/ppm-hr, respectively, in semicontinuous activated sludge (SCAS) tests and a half-life of about 11 days was observed in a river die-away test for isodecyl diphenyl phosphate at an initial concn of 1 ppm(1).

The Henry's Law constant for isodecyl diphenyl phosphate can be estimated to be 4.36X10-7 atm-cu m/mole at 25 °C using a chemical structure estimation method(2,SRC). According to a suggested classification scheme(1), this Henry's Law constant indicates that isodecyl diphenyl phosphate volatilizes slowly from water. The volatilization half-life of isodecyl diphenyl phosphate from a model river 1 m deep flowing 1 m/sec with a wind velocity of 3 m/sec can be estimated to be approximately 166 days based on the Henry's Law constant(1,SRC).

The signs of poisoning due to organophosphorus cmpd are those due to accumulation of acetylcholine & hence overstimulation of parasympathetic nervous system. It is usual to divide them under 3 headings: muscarinic, nicotinic & central. Muscarinic signs ... consist of hypersalivation, lacrimation, sweating & nasal discharge. Miosis, dyspnea, vomiting, diarrhea & frequency of urination ... Nicotinic effects consist of fasciculation of muscles, weakness & paralysis. Central nervous system effects include nervousness, apprehension, ataxia, convulsions & coma. Death is due to resp failure, or sometimes cardiac arrest. There is little difference between signs produced by different organophosphorus compounds, but route of absorption may influence one system more than another. /Organophosphorus cmpd/

The rate constant for the vapor-phase reaction of isodecyl diphenyl phosphate with photochemically produced hydroxyl radicals has been estimated to be 4.38X10-11 cu cm/molecule-sec at 25 °C which corresponds to an atmospheric half-life of about 8.8 hrs at an atmospheric concn of 5X10+5 hydroxyl radicals per cu cm(1,SRC). Phosphate esters are generally resistant to hydrolysis in neutral or acid waters (pH 5-7)(3). Aqueous hydrolysis may be an important degradative pathway of isodecyl diphenyl phosphate in the environment under mildly alkaline conditions (pH 9)(2). By analogy, half-lives of the first hydrolysis step for triphenyl phosphate have been measured to range from 0.23 to 7.5 days at pH 9.5 to pH 8.2, respectively(2-3).

Occupational exposure to isodecyl diphenyl phosphate will occur via dermal contact and inhalation of vapor. (SRC)

NIOSH (NOES Survey 1981-1983) has statistically estimated that 13,976 workers are potentially exposed to isodecyl diphenyl phosphate in the USA(1).

Isodecyl diphenyl phosphate may be released to the environment from its production, processing, and use. The major sources of release are expected to be volatilization from plastic items where it may be used as a plasticizer and leakage from hydraulic fluids. During production, primary releases are to soil via land disposal of solid or semi-solid waste. If released to water, isodecyl diphenyl phosphate will readily biodegrade under aerobic conditions (half-life of 11 days or less in river water). However, biodegradation in benthic sediments is unclear. Aqueous hydrolysis may become increasingly important with increasing alkalinity but no rate data were located. Isodecyl diphenyl phosphate will partition from the water column to sediment and suspended material; also, it is expected to bioconcentrate in aquatic organisms. If released to soil, biodegradation will be the predominant fate process and aqueous hydrolysis may be important in alkaline soils. Isodecyl diphenyl phosphate will adsorb strongly to soil and leaching will not be important. If released to the atmosphere, vapor-phase isodecyl diphenyl phosphate is expected to degrade by reaction with photochemically produced hydroxyl radicals (estimated half-life of 8.8 hrs). Particulate isodecyl diphenyl phosphate will be removed from the atmosphere via wet and dry deposition. Occupational exposure to isodecyl diphenyl phosphate will occur via dermal contact and inhalation of vapor. (SRC)

A comatose patient who is diaphoretic, has pinpoint pupils and the odor of an insecticide on clothing or breath, and is noted to have muscle fasciculations represents the classic presentation of organophosphate poisoning. ... Specific steps in management include the following. 1. Decontamination. ... 2 Airway. Establish an airway if necessary. ... 3. Respiratory Status. Respiratory distress, in fact, is commonly found in these patients from multiple causes. ... 4. Cardiac Monitoring. ... 5. Cholinesterase Level. ... 6. Pralidoxime. Pralidoxime is the treatment of choice for organophosphate poisoning and should be used for nearly all patients with clinically significant orgnophosphate poisoning,particularly whose patients with muscular fasciculations and weakness. ... 7. Atropine. Atropine is the physiologic antidote for organophosphate poisoning. A trial dose of atropine should be instituted on clinical ground when one suspects organophosphate intoxication. /Organophosphate poisoning/

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. Phosphoric acid, isodecyl diphenyl ester is included on this list.

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, use, and exposure to EPA as cited in the preamble of the 51 FR 41329.