- Tritolyl phosphate
- Phosphoric acid tris(methylphenyl) ester
- o-Cresyl phosphate
- o-Tolyl phosphate
- Tri-o-tolyl phosphate
Colorless to pale yellow, oily, odorless liquid. Tricresyl phosphate (TCP) exists in three isomeric forms: ortho, meta, and para. The commercial product is a mixture of the three forms with as little of the highly toxic ortho-isomer (TOCP) as possible. The meta- and para-isomers are relatively inactive.
Plasticizer in lacquers & varnishes.
Registry Numbers and Inventories.
EC Index Number
Toxic; Dangerous for the Environment
R 39/23.24/25 51/53
S 20/21 45 28A 61
Drug; Mutagen; Reproductive Effector
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
2E-6 (25 C)
Vapor density (air=1)
Odor Threshold Odor threshold Odorless
1.1955 g/cm3 (20 C)
Solubility in water
144.67 cp (18 C)
1.56703 (20 C)
2.87 (25 C)
6.73 (25 C)
Heat of vaporization
Hazards and Protection.
Keep in a tightly closed galvanized steel container, stored in a cool, dry, ventilated area away from direct sunlight and open flames. Protect against physical damage. Isolate from any source of heat or ignition. Containers should be effectively sealed and clearly marked. Tricresyl phosphates should not be used in plastic articles which are likely to come into contact with foodstuffs or clothing.
Do not breathe dust, vapor, mist, or gas. Do not get in eyes, on skin, or on clothing. Use only in a chemical fume hood.
Skin: Wear impervious gloves. Clothing: Wear appropriate protective clothing to prevent skin exposure.
A half facepiece particulate respirator (NIOSH type N95 or better filters) may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest.. A full-face piece particulate respirator (NIOSH type N100 filters) may be worn up to 50 times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency, or respirator supplier, whichever is lowest. If oil particles (e.g. lubricants, cutting fluids, glycerine, etc.) are present, use a NIOSH type R or P filter. For emergencies or instances where the exposure levels are not known, use a full-facepiece positive-pressure, air-supplied respirator.
Keep unnecessary and unprotected personnel from entering. Contain and recover liquid when possible. Collect liquid in an appropriate container or absorb with an inert material (e. g., vermiculite, dry sand, earth), and place in a chemical waste container. Do not use combustible materials, such as saw dust. Do not flush to sewer.
Stable under ordinary conditions of use and storage. Hydrolyzes slowly at room temperature under wet alkaline conditions.
Carbon monoxide, oxides of phosphorus, carbon dioxide.
Lower exp. limit, %
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Extinguishing media: Use carbon dioxide or dry chemical.
Slight risk when exposed to heat or flame.
Containers may explode when heated. Runoff may pollute waterways.
During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion.
TLV: ppm; 0.1 mg/m3 (skin) (ACGIH 1992-1993). OSHA PEL: TWA 0.1 mg/m3 NIOSH REL: TWA 0.1 mg/m3 skin NIOSH IDLH: 40 mg/m3
Repeated exposure may cause symptoms similar to those listed for acute effects. TCP inhibits cholinesterase. Neurologic damage can be severe and permanent.
Causes irritation to the gastrointestinal tract. Symptoms may include nausea, vomiting and diarrhea. Breathing or swallowing large quantities may cause neurological disturbances which may progress to delayed neurotoxicity characterized by ataxia and tremors.
Since TCP has low volatility, vapor inhalation is unlikely at normal temperatures; however, it may be a hazard if boiled. Mist or vapor can cause irritation to respiratory tract. May be absorbed into the bloodstream with symptoms similar to ingestion.
Causes irritation to skin. Symptoms include redness, itching, and pain. May be absorbed through the skin without local irritant effects; symptoms similar to ingestion.
Causes irritation, redness, and pain. Rapid eye oscillation with dizziness may occur.
Induce vomiting immediately as directed by medical personnel. Never give anything by mouth to an unconscious person. Consider gastric lavage if patients are comatose or at risk of convulsing. Since prolonged diarrhea may occur, avoid cathartic administration.
Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention.
Immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Get medical attention. Wash clothing before reuse. Thoroughly clean shoes before reuse.
Immediately flush eyes with plenty of water for at least 15 minutes, lifting lower and upper eyelids occasionally. Get medical attention immediately.