1,2,3-trimethylbenzene

This chemical does not meet GHS hazard criteria for 2.5% (42 of 1654) of reports.

H226 (95%): Flammable liquid and vapor [Warning Flammable liquids]

H315 (87.1%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (80.7%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H335 (35.7%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1654 reports by companies from 25 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 42 of 1654 reports by companies.

There are 24 notifications provided by 1612 of 1654 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

This chemical does not meet GHS hazard criteria for 1.8% (28 of 1532) of reports.

H226 (96.1%): Flammable liquid and vapor [Warning Flammable liquids]

H302+H312 (35.4%): Harmful if swallowed or in contact with skin [Warning Acute toxicity, oral; acute toxicity, dermal]

H302 (66.4%): Harmful if swallowed [Warning Acute toxicity, oral]

H304 (15.2%): May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H312 (77.8%): Harmful in contact with skin [Warning Acute toxicity, dermal]

H315 (91.7%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (81.5%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H332 (28.5%): Harmful if inhaled [Warning Acute toxicity, inhalation]

H335 (12.5%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

H411 (17.6%): Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P270, P271, P273, P280, P301+P316, P301+P317, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P317, P319, P321, P330, P331, P332+P317, P337+P317, P362+P364, P370+P378, P391, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1532 reports by companies from 29 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 28 of 1532 reports by companies.

There are 28 notifications provided by 1504 of 1532 reports by companies with hazard statement code(s).

H401: Toxic to aquatic life [Hazardous to the aquatic environment, acute hazard]

H411: Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P273, P391, and P501 (click each P-code to see the statement)

H226: Flammable liquid and vapor [Warning Flammable liquids]

H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H315: Causes skin irritation [Warning Skin corrosion/irritation]

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

P210, P233, P240, P241, P242, P243, P260, P261, P264, P264+P265, P270, P271, P280, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

P210, P233, P240, P241, P242, P243, P261, P271, P280, P303+P361+P353, P304+P340, P319, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Fresh air, rest. Refer for medical attention.

Rinse skin with plenty of water or shower.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Do NOT induce vomiting. Refer for medical attention .

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap wash - If this chemical contacts the skin, wash the contaminated skin with soap and water.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Use alcohol-resistant foam, foam, powder, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water.

This chemical is a flammable liquid. Poisonous gases are produced in fire. Small fires: dry chemical, carbon dioxide, water spray, or alcohol-resistant foam. Large fires: water spray, fog, or alcohol foam. Move container from fire if you can do so without risk. Spray cooling water on containers that are exposed to flames until well after fire is out. For massive fire in cargo area, use unmanned hose holder or monitoring nozzles; if this is impossible, withdraw from area and let fire burn. Isolate for one-half mile in all directions if tank car or truck is involved in fire. Vapors are heavier than air and will collect in low areas. Vapors may travel long distances to ignition sources and flashback. Vapors in confined areas may explode when exposed to fire. Containers may explode in fire. Storage containers and parts of containers may rocket great distances, in many directions. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Notify local health and fire officials and pollution control agencies. From a secure, explosion-proof location, use water spray to cool exposed containers. If cooling streams are ineffective (venting sound increases in volume and pitch, tank discolors, or shows any signs of deforming), withdraw immediately to a secure position. If employees are expected to fight fires, they must be trained and equipped in OSHA 1910.156.

This chemical is a flammable liquid. Poisonous gases are produced in fire. Small fires: dry chemical, carbon dioxide, water spray, or alcohol-resistant foam. Large fires: water spray, fog, or alcohol foam. Move container from fire if you can do so without risk. Spray cooling water on containers that are exposed to flames until well after fire is out. For massive fire in cargo area, use unmanned hose holder or monitoring nozzles; if this is impossible, withdraw from area and let fire burn. Isolate for one-half mile in all directions if tank car or truck is involved in fire. Vapors are heavier than air and will collect in low areas. Vapors may travel long distances to ignition sources and flashback. Vapors in confined areas may explode when exposed to fire. Containers may explode in fire. Storage containers and parts of containers may rocket great distances, in many directions. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Notify local health and fire officials and pollution control agencies. From a secure, explosion-proof location, use water spray to cool exposed containers. If cooling streams are ineffective (venting sound increases in volume and pitch, tank discolors, or shows any signs of deforming), withdraw immediately to a secure position. If employees are expected to fight fires, they must be trained and equipped in OSHA 1910.156. /Trimethyl benzenes/

Collect leaking and spilled liquid in covered containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer.

Evacuate and restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Establish forced ventilation to keep levels below explosive limit. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or similar material and deposit in sealed containers. Keep this chemical out of a confined space ... because of the possibility of an explosion ... It may be necessary to contain and dispose of this chemical as a hazardous waste. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection or your regional office of the federal EPA for specific recommendations. If employees are required to clean up spills, they must be properly trained and equipped. OSHA 1910.120(q) may be applicable.

Evacuate and restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Establish forced ventilation to keep levels below explosive limit. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or similar material and deposit in sealed containers. Keep this chemical out of a confined space ... because of the possibility of an explosion ... It may be necessary to contain and dispose of this chemical as a hazardous waste. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection or your regional office of the federal EPA for specific recommendations. If employees are required to clean up spills, they must be properly trained and equipped. OSHA 1910.120(q) may be applicable. /Trimethyl benzenes/

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.

Incineration /SRP: with appropriate emission controls/.

Incineration /SRP: with appropriate emission controls/. /Trimethyl benzenes/

Above 44 °C use a closed system, ventilation, and explosion-proof electrical equipment. Prevent build-up of electrostatic charges (e.g., by grounding).

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.

The worker should immediately wash the skin when it becomes contaminated.

Work clothing that becomes wet or significantly contaminated should be removed or replaced.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

Fireproof. Well closed. Separated from oxidants.

Prior to working with this chemical you should be trained on its proper handling and storage. Before entering a confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Trimethylbenzene must be stored to avoid contact with oxidizers (such as perchlorates, peroxides, permanganates, chlorates, and nitrates), and strong oxidizers (such as chlorine, bromine, and fluorine) since violent reactions occur. Store in tightly closed containers in a cool, well-ventilated area away from heat. Sources of ignition such as smoking and open flames are prohibited where this chemical is used, handled, or stored in a manner that could create a potential fire or explosion hazard. Metal containers involving the transfer of 5 gallons or more of this chemical should be grounded and bonded. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters. Use only nonsparking tools and equipment, especially when opening and closing containers of this chemical.

Prior to working with this chemical you should be trained on its proper handling and storage. Before entering a confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Trimethylbenzene must be stored to avoid contact with oxidizers (such as perchlorates, peroxides, permanganates, chlorates, and nitrates), and strong oxidizers (such as chlorine, bromine, and fluorine) since violent reactions occur. Store in tightly closed containers in a cool, well-ventilated area away from heat. Sources of ignition such as smoking and open flames are prohibited where this chemical is used, handled, or stored in a manner that could create a potential fire or explosion hazard. Metal containers involving the transfer of 5 gallons or more of this chemical should be grounded and bonded. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters. Use only nonsparking tools and equipment, especially when opening and closing containers of this chemical. /Trimethyl benzenes/

20.0 [ppm]

AEGL 1: Notable discomfort, irritation, or certain asymptomatic non-sensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure (Unit: ppm)

AEGL 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape (Unit: ppm)

AEGL 3: Life-threatening health effects or death (Unit: ppm)

NR = Not recommended due to insufficient data

AEGLs Status: Final

140 [ppm]

360 [ppm]

470 [ppm]

TWA 25 ppm (125 mg/m3)

none See Appendix G

See: IDLH INDEX

10.0 [ppm]

8 hr Time Weighted Avg (TWA): 25 ppm

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded.

100 mg/m

A harmful contamination of the air will be reached rather slowly on evaporation of this substance at 20 °C.

The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the central nervous system. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis.

Wear protective gloves and clothing to prevent any reasonable probability of skin contact. Safety equipment suppliers/manufacturers can provide recommendations on the most protective glove/clothing material for your operation. All protective clothing (suits, gloves, footwear, headgear) should be clean, available for work each day, and put on before work. Contact lenses should not be worn when working with this chemical. Wear splash-proof chemical goggles and face shield unless full face-piece respiratory protection is worn. Employees should wash immediately with soap when skin is wet or contaminated. Provide emergency showers and eyewash.

Wear protective gloves and clothing to prevent any reasonable probability of skin contact. Safety equipment suppliers/manufacturers can provide recommendations on the most protective glove/clothing material for your operation. All protective clothing (suits, gloves, footwear, headgear) should be clean, available for work each day, and put on before work. Contact lenses should not be worn when working with this chemical. Wear splash-proof chemical goggles and face shield unless full face-piece respiratory protection is worn. Employees should wash immediately with soap when skin is wet or contaminated. Provide emergency showers and eyewash. /Trimethyl benzenes/

Wear appropriate personal protective clothing to prevent skin contact.

Wear appropriate eye protection to prevent eye contact.

Important additional information about respirator selection

NO open flames, NO sparks and NO smoking. Above 44 °C use a closed system, ventilation and explosion-proof electrical equipment. Prevent build-up of electrostatic charges (e.g., by grounding).

PREVENT GENERATION OF MISTS!

Use ventilation, local exhaust or breathing protection.

Protective gloves.

Wear safety spectacles.

Do not eat, drink, or smoke during work.

Colorless liquid; Insoluble in water; [ICSC]

COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Clear, colorless liquid with a distinctive, aromatic odor.

Colorless liquid

Clear, colorless liquid

Distinctive, aromatic odor

176.12 °C

176.12 °C @760 [mm Hg]

-25.4 °C

44 to 53 °C (closed cup)

111 °F (44 °C) (Closed cup)

Miscible with ethanol, ether, acetone, benzene, petroleum ether, carbon tetrachloride

In water, 75.2 mg/L at 25 °C

Solubility in water, g/100ml: 0.005

0.8944 g/cu cm at 20 °C

0.89 g/cm³

Relative density of the vapour/air-mixture at 20 °C (air = 1): 1.01

0.8944 @ 20°C

4.15 (Air = 1)

Relative vapor density (air = 1): 4.1

1.69 [mmHg]

1.69 mm Hg at 25 °C

Vapor pressure, kPa at 20 °C: 0.18

0.75 [mm Hg] @15 °C

(62 °F): 1 mmHg

log Kow = 3.66

Henry's Law constant = 4.36X10-3 atm-cu m/mol at 25 °C

470 to 550 °C

878 °F (470 °C)

When heated to decomposition it emits acrid smoke and irritating fumes.

49.05 kJ/mol at 20 °C

Index of refraction: 1.5139 at 20 °C/D

Conversion factors: 1 mg/cu m = 0.20 ppm; 1 ppm = 5.00 mg/cu m

Heat of formation: -58.5 kJ/mol at 298.15 K (liquid); -9.5 kJ/mol at 298.15 K (gas)

Standard molar entropy: 267.9 J/mol K at 298.15 K

Molar heat capacity: 216.4 J/mol K at 298.15 K and constant pressure

Hydroxyl radical reaction rate constant = 3.27X10-11 cu cm/molec-sec at 25 °C

13C nuclear magnetic resonance spectrum

Boiling point

Chemical shift

Oxidizers (perchlorates, peroxides, permanganates, chlorates, nitrates), strong oxidizers (chlorine, bromine, fluorine), and nitric acid.

Oxidizers (perchlorates, peroxides, permanganates, chlorates, nitrates), strong oxidizers (chlorine, bromine, fluorine), and nitric acid. /Trimethyl benzenes/

Oxidizers, nitric acid

1,2,3-Trimethylbenzene

Hematologic

Respiratory

1 x 10 ^-2 mg/kg-day

4 x 10 ^-2 mg/kg-day

6 x 10 ^-2 mg/m^3

2 x 10 ^-1 mg/m^3

Volatile Organic Compound (VOC)

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

The substance can be absorbed into the body by inhalation.

inhalation, ingestion, skin and/or eye contact

Confusion. Dizziness. Headache. Vomiting. Drowsiness. Cough. Sore throat.

Redness.

Redness. Pain.

irritation eyes, skin, nose, throat, respiratory system; bronchitis; hypochromic anemia; headache, drowsiness, lassitude (weakness, exhaustion), dizziness, nausea, incoordination; vomiting, confusion; chemical pneumonitis (aspiration liquid)

Eyes, skin, respiratory system, central nervous system, blood

Neurotoxin - Acute solvent syndrome

PDF Document

See the IRIS entry for 1,2,3-Trimethylbenzene

IRIS Current

LD50 Rat oral 8970 mg/kg

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Aromatic hydrocarbons and related compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . /Aromatic hydrocarbons and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Consider drug therapy for pulmonary edema ... . Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... .Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Aromatic hydrocarbons and related compounds/

/HUMAN EXPOSURE STUDIES/ TMBs or their metabolites have been suggested as suitable biomarkers of exposure to white spirit and other distillation products. ... The objective of this study was to compare the toxicokinetics of inhaled 1,2,4-trimethylbenzene (1,2,4-TMB) in man after exposure to white spirit with that observed after exposure to 1,2,4-TMB alone. ... The toxicokinetics were studied in 9 male, healthy volunteers exposed to solvent vapors in an exposure chamber for 2 hr during a work load of 50 W. The subjects were exposed to 11 mg/cu m of 1,2,4-TMB on two occasions; during exposure to 1,2,4-TMB vapor alone and during exposure to 300 mg/cu m of white spirit. ... Further the occurrence of acute effects was studied by means of a questionnaire. Irritation and central nervous system symptoms were recorded by ratings on a 100-mm visual analogue scale. ... No irritation or central nervous system effects were reported at these conditions.

/HUMAN EXPOSURE STUDIES/ The only published report of human exposure described the results of an investigation of 27 persons who worked for a number of years with a solvent called "Fleet-X-DV-99" containing 30% mesitylene and 50% pseudocumene. A significant number of the exposed individuals complained of nervousness, tension, anxiety, and asthmatic bronchitis. In addition, the peripheral blood showed a tendency to hypochromic anemia and a deviation from normal in the coagulability of the blood. Hydrocarbon vapor concentrations ranged from 10 to 60 ppm. The authors attributed these findings to trimethyl benzene exposure, but /it was/ pointed out that contamination of the solvent with benzene was probably responsible for the blood abnormalities. ...A level of 35 to 50 ppm caused no complaints of mucous membrane irritation.

/SIGNS AND SYMPTOMS/ Effects of short-term exposure: The substance is irritating to the eyes, the skin and the respiratory tract. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis. The substance may cause effects on the central nervous system. Effects of long-term or repeated exposure: The liquid defats the skin. Lungs may be affected by repeated or prolonged exposure, resulting in chronic bronchitis. The substance may have effects on the blood and central nervous system. ...Use of alcoholic beverages enhances the harmful effect.

/SURVEILLANCE/ ... The aim of this investigation was to assess the incidence of hearing and vestibular disorders (using modem audiological and vestibular tests) in 61 workers exposed to a mixture of organic solvents at the production of paints and varnishes; the control group included 40 age-matched non-exposed subjects. Environmental and biological monitoring revealed that the most significant exposure can be attributed to the following mixture constituents: ethylbenzene, xylene and trimethylbenzene isomers such as pseudocumene, mesitylene and hemimellitene. Electronystagmographic examinations showed the symptoms of vestibular dysfunction, as well as the decreased duration, amplitude and slow phase angular velocity of induced nystagmus in 47.5% of the subjects exposed versus 5% of controls. This was accompanied by sensorineural high frequency hearing loss, identified by means of pure tone audiometry in 42% of those exposed versus 5% controls, and reduced amplitudes of transiently evoked and distortion-product otoacoustic emissions. The findings closely correspond with the rate of the total exposure to the solvent mixture. ...

/BIOMONITORING/ ... The aim of this study was to obtain toxicokinetic data on the absorption and elimination of trimethylbenzene and its metabolites in biological fluids and to investigate the relationship between the biological indices of exposure and the absorbed dose. Eight-hour inhalation tests were performed in a toxicological chamber, The subjects were eight volunteers aged 20-39 with no history of exposure to TMB. They were exposed to pseudocumene, mesitylene or hemimellitene at concentrations ranging from 5 to 150 mg/cu m air. Exhaled air, capillary blood and urine samples were collected before, during and after the exposure. The determinations of TMB or its metabolites were performed using gas chromatography ... . Pulmonary ventilation in the volunteers ranged from 0.56 to 1.0 cu m/hr. The retention of 1,2,4-TMB; 1,3,5-TMB; 1,2,3-TMB in the lungs was 68%, 67% and 71%, respectively. The elimination of TMB from capillary blood occurred in accordance with the open three-compartment model. Urinary excretion of dimethylbenzoic acids (DMBA) proceeded according to the open two-compartment model. Based on the toxicokinetic data, a simulation model of accretion and excretion of DMBA in urine during a 14-day period was developed. The highest rates of metabolite excretion and the highest quantities of DMBA in urine during 24-hr intervals were observed on day 5 of exposure. The relationship between the levels of TMB or DMBA in biological material and TMB air concentration or absorbed dose were determined. To select the urine fraction suitable for determining occupational TMB exposure, linear regression analysis was performed. The biological exposure limit (BEL) for TMB has been proposed, with the current maximum allowable concentration (MAC) value of 100 mg/cu m (Polish standard) baseline value.

/SIGNS AND SYMPTOMS/ The substance is irritating to the eyes, the skin and the respiratory tract. The substance may cause effects on the central nervous system. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis. ...Use of alcoholic beverages enhances the harmful effect.

/LABORATORY ANIMALS: Acute Exposure/ Liquid trimethyl benzene was a primary skin irritant; however, systemic intoxication due to percutaneous absorption was considered unlikely. Pulmonary instillation of liquid trimethyl benzene caused chemical pneumonitis at the site of contact.

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ ... Rats /exposed/ at 1700 ppm of an isomeric mixture of trimethyl benzene for periods of 10 to 21 days ... no fatalities or other toxicological effects. Exposure for 4 months to the same concentration caused reduced body weight gain, accompanied by progressively increasing lymphopenia and neutrophilia; however, it is not clear if the latter changes were due to the benzene content of the solvent preparation studied. Marked depression of the CNS was also observed.

/LABORATORY ANIMALS: Acute Exposure/ Sensory respiratory irritation effects of trimethylbenzene isomers (TMBs) (hemimellitene, mesitylene and pseudocumene) in male Balb/C mice were investigated in conditions of acute exposure ... . The pseudocumene, mesitylene and hemimellitene concentrations depressing the respiratory rate to 50% (RD50) were 578, 519, 541 ppm, respectively ...

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ Toxic effects of exposure to 1,2,3-trimethylbenzene (hemimellitene) in the condition of subchronic inhalation experiment were examined. Rats were exposed to vapors of hemimellitene at concentrations of 123 mg/cu m, 492 mg/cu m and 1230 mg/cu m, 6 hr/day, 5 days/week for 3 months. After termination of a 3-month inhalation, animals were necropsied. Blood samples were obtained and selected organs were weighed and prepared for histological examinations. Subchronic inhalation exposure to hemimellitene resulted in an overall, low systemic toxicity. There were no changes in body weight gain and food consumption. At a concentration of 1230 mg/cu m, the increase in relative liver weight was observed in male rats. It was accompanied by slight increase in sorbitol dehydrogenase activity. The increase in alkaline phosphatase activity was found in females only. Some disturbances in hematological parameters, characterized by the decrease in red blood cells and slight increase in white blood cells, segmented neutrophils and lymphocytes were observed in rats at high exposure concentration of 1230 mg/cu m. The pulmonary lesions as well as the increased number of goblet cells and interstitial lung parenchyma infiltration were noted in male and female rats from the highest exposure groups.

/LABORATORY ANIMALS: Neurotoxicity/ ... The present experiment ... investigated the effects of a repeated four-week (6 hr/day, 5 days/week) inhalation exposure to 1,2,3-TMB (hemimellitene--HM) at concentrations of 0, 25, 100 or 250 ppm on radial-maze performance, open-field activity, passive and active avoidance learning, and on the shock-induced changes in latency of the paw-lick response to heat (hot-plate test). The tests were performed between days 14 and 61 after the last exposure. No significant effects on radial-maze performance and open-field activity were noted in any of the dose groups. In the remaining tests effects of exposure were noted but, similarly as in the case of 1,2,4-TMB (pseudocumene--PS) exposure, the concentration-effect relationship was not linear. In rats exposed to HM at 25 or 100 ppm, but not 250 ppm, learning of the passive avoidance, ie refraining from performance of a punished response (stepping off an elevated platform) was significantly impaired. Moreover, in rats exposed to 100, but not 250 ppm of HM, acquisition of the two-way active avoidance in the shuttle-box was slower and the footshock-induced increase in latency of the paw-lick response to heat persisted longer than in the unexposed animals. ...

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 7000 ug/L for 24 hr

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 5600 ug/L for 48 hr

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 5400 ug/L for 96 hr

3.40e+02

2.00e+03

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 7000 ug/L for 24 hr

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 5600 ug/L for 48 hr

LC50; Species: Palaemonetes pugio (Daggerblade grass shrimp); Conditions: saltwater, static, 21 °C, pH 8.1, salinity 15 parts per thousand, dissolved oxygen >5.0 mg/L; Concentration: 5400 ug/L for 96 hr

3.40e+02

2.00e+03

6.30e+01

2.60e+02

5.50e+01

5.00e+01

8.10e-02

1.00e-02

6.00e-02

Volatile

2.93e+02

1.00e+03

6.10e+03

1.90e+02

7.90e+02

1.60e+02

Trimethylbenzenes' production and use as a dyestuff intermediate, solvent, paint thinner, in the manufacture of perfumes and as inert ingredients in pesticide formulations may result in their release to the environment through various waste streams. Trimethylbenzenes are released directly to the environment as components of gasoline and as emissions from gasoline-powered vehicles, municipal waste-treatment plants, and coal-fired power stations. If released to the atmosphere, trimethylbenzenes will exist solely in the vapor phase in the ambient atmosphere, based on a vapor pressure range of 1.69 to 2.10 mm Hg at 25 °C. Vapor-phase trimethylbenzenes are degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and nitrate radicals with half-lives of about 7 hours and 10-67 days, respectively. If released to soil, a measured Koc values of 501 to 1,445 suggest trimethylbenzenes will have low mobility in soil. Volatilization from moist and dry soil surfaces should occur based on measured Henry's Law constants of 4.36X10-3 to 8.77X10-3 atm-cu m/mole. Trimethylbenzenes are expected to biodegrade slowly in both soil and water based on screening studies for the various isomers. If released to water, trimethylbenzenes may adsorb to sediment or particulate matter based on the Koc values. Volatilization from water surfaces is expected to occur based on the Henry's Law constants for the isomers. Estimated volatilization half-lives for a model river and model lake range are approximately 3 hours and 4 days, respectively. Hydrolysis is not expected to be an important environmental fate process since trimethylbenzenes lack functional groups that hydrolyze under environmental conditions. BCF values of 42-328, measured in carp suggest bioconcentration in aquatic organisms is moderate to high. Occupational exposure to trimethylbenzenes may occur through inhalation and dermal contact with this compound at workplaces where it is produced or used. The general population may be exposed to trimethylbenzenes via inhalation of ambient air, particularly in areas with heavy vehicular traffic, ingestion of food and drinking water, or dermal exposure to products such as gasoline which contain trimethylbenzenes. (SRC)

1,2,3-Trimethylbenzene's production and use as a solvent and in dye and perfume manufacturing may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 1.69 mm Hg at 25 °C indicates 1,2,3-trimethylbenzene will exist solely as a vapor in the atmosphere. Vapor-phase 1,2,3-trimethylbenzene will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 12 hours. 1,2,3-Trimethylbenzene also reacts with ozone and nitrate radicals in the atmosphere; the half-life for these reactions are 20 years and 60 days, respectively. If released to soil, 1,2,3-trimethylbenzene is expected to have low mobility based upon Koc values of 1,096 and 630. Volatilization from moist soil surfaces is expected to be an important fate process based upon a Henry's Law constant of 4.36X10-3 atm-cu m/mole. 1,2,3-Trimethylbenzene may volatilize from dry soil surfaces based upon its vapor pressure. 99 and 100% removal in acclimated sludge and activated sludge, respectively, indicate that biodegradation may be an important environmental fate process. If released into water, 1,2,3-trimethylbenzene is expected to adsorb to suspended solids and sediment based upon the Koc values. Biodegradation of 1,2,3-trimethylbenzene was classified as moderate in a marine environment but not likely in anaerobic environments. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 3.4 hours and 4.4 days, respectively. A BCF range of 133-259 suggests bioconcentration in aquatic organisms is high. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to 1,2,3-trimethylbenzene may occur through inhalation and dermal contact with this compound at workplaces where 1,2,3-trimethylbenzene is produced or used. Monitoring and use data indicate that the general population may be exposed to 1,2,3-trimethylbenzene via inhalation of ambient air, ingestion of food and drinking water, and dermal contact with this compound and other products containing 1,2,3-trimethylbenzene. Workers and the general population that operate gasoline-pumping stations and off-set printers may have an especially high risk of exposure to 1,2,3-trimethylbenzene. (SRC)

Trimethylbenzenes are found in coal tar ... occurring in some mineral oils and are formed during the processing of crude oil

1,2,3-Trimethylbenzene is a volatile component of plums(1).

/1,2,3-Trimethylbenzene is/ found in coal tar ... occurring in some mineral oils /and is/ formed during the processing of crude oil

Trimethylbenzenes' production and use as dyestuff intermediates, solvents, paint thinners, in the manufacture of perfumes(1) and as inert ingredients in pesticide formulations(2) may result in their release to the environment through various waste streams(SRC). Trimethylbenzenes are released directly to the environment as components of gasoline(3) and as emissione from gasoline-powered vehicles(4,5), municipal waste-treatment plants(6), and coal-fired power stations(7).

1,2,3-Trimethylbenzene's production and use as a solvent and in dye and perfume manufacturing(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a recommended classification scheme(1), a Koc range of 501 to 1,445 measured in soil(2-9), suggests that trimethylbenzenes will have low mobility in soil(SRC). Volatilization of trimethylbenzenes from moist soil surfaces may be important(SRC) based on Henry's Law constants of 4.36X10-3 to 8.77 atm-cu m/mole(10). Volatilization from dry soil surfaces is expected(SRC), based on a vapor pressure range of 1.69 to 2.48 mm Hg(11). Screening studies indicate that trimethylbenzenes are slow to degrade and are not classified as readily biodegradable under aerobic conditions(12,13).

AQUATIC FATE: Based on a recommended classification scheme(1), a Koc range of 501-1,445 measured in soil(2-9), indicates that trimethylbenzenes are expected to adsorb to sediment and particulate matter in the water column(SRC). Trimethylbenzenes are expected to volatilize from water surfaces(10) based on Henry's Law constants of 4.36X10-3 to 8.77 atm-cu m/mole(11). Using these Henry's Law constants and an estimation method(3), volatilization half-lives for a model river and model lake are approximately 3 hours and 4 days, respectively(SRC). According to a classification scheme(12), BCF values of 23-342 measured in fish(13), suggests the potential for bioconcentration in aquatic organisms is moderate to high(SRC). Screening studies indicate that trimethylbenzenes are slow to degrade and are not classified as readily biodegradable under aerobic conditions(13,14).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), trimethylbenzenes, which have a vapor pressure range of 1.69 to 2.48 mm Hg 25 °C(2), will exist solely as vapors in the ambient atmosphere. Vapor-phase trimethylbenzenes are degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and nitrate radicals(SRC). The half-life for the reaction with hydroxyl radicals is estimated to be about 7 to 12 hours calculated from a rate constant ranges of 3.25X10-11 to 5.75X10-11 cu cm/molecule-sec at 25 °C(3). The half-life for the reaction in air with nitrate radicals is estimated as 10-67 days(SRC), calculated from rate constants of 2.4X10-16 and 1.60X10-15 cu cm/molecule-sec at 25 °C(4). Trimethylbenzenes do not contain chromophores that absorb wavelengths >290 nm(5) and therefore are not expected to be susceptible to direct photolysis by sunlight(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 1,096(2) and 630(3) indicate that 1,2,3-trimethylbenzene is expected to have low mobility in soil(SRC). Volatilization of 1,2,3-trimethylbenzene from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 4.36X10-3 atm-cu m/mole(4). 1,2,3-Trimethylbenzene is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.69 mm Hg(5). Biodegradation of 1,2,3-trimethylbenzene may occur in aerobic environments(6) but is likely to be slow based upon 0% theoretical BOD in the Japanese MITI test(8); it is unlikely to biodegrade in anaerobic environments(7).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 1,096(2) and 630(3) indicate that 1,2,3-trimethylbenzene is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(4) based upon a Henry's Law constant of 4.36X10-3 atm-cu m/mole(5). Using this Henry's Law constant and an estimation method(4), volatilization half-lives for a model river and model lake are 3.4 hours and 4.4 days, respectively(SRC). According to a classification scheme(6), a BCF range of 133-259(7) suggests bioconcentration in aquatic organisms is high(SRC). Biodegradation of 1,2,3-trimethylbenzene may occur in oxygenated water(8) but is likely to be slow based upon 0% theoretical BOD in the Japanese MITI test(7); it is unlikely to biodegrade in anaerobic environments(9).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,2,3-trimethylbenzene, which has a vapor pressure of 1.69 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,2,3-trimethylbenzene 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 3.27X10-11 cu cm/molecule-sec at 25 °C(3). 1,2,3-Trimethylbenzene also reacts with ozone and nitrate radicals in the atmosphere; the half-life for these reactions are 20 years(4) and 60 days, respectively(5).

AEROBIC: Screening studies indicate that trimethylbenzenes are slow to degrade and are not classified as readily biodegradable under aerobic conditions(1,2).

AEROBIC: 1,2,3-Trimethylbenzene, present at 100 mg/L, reached 0% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/L and the Japanese MITI test(1). 1,2,3-Trimethylbenzene had a 99(2) and 100%(3) removal in acclimated sludge and activated sludge, respectively. The concentration of 1,2,3-trimethylbenzene was reduced from 4.24 mg/L to 0.0 mg/L in 25 days at 30 °C using a sewage inocculum(4). Biodegradation of 1,2,3-trimethylbenzene was classified as moderate in a marine environment(5). 1,2,3-Trimethylbenzene was reduced to zero in 23 days in sewage using a natural microbial flora with aeration and was reduced without aeration(6).

ANAEROBIC: Little or no degradation of 1,2,3-trimethylbenzene was observed in 65 days at 25 °C(1) and 188 days(2) in anaerobic groundwater media. 1,2,3-Trimethylbenzene was found to be recalcitrant in anaerobic groundwater studies(3-4). 1,2,3-Trimethylbenzene is not biodegraded anaerobically in soil or water(5).

The rate constants for the vapor-phase reaction of trimethylbenzenes with photochemically-produced hydroxyl radicals range from 3.25X10-11 to 5.75X10-11 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 7 to 12 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of trimethylbenzenes with nitrate radicals ranges from 5.4X10-16 to 1.60X10-15 cu cm/molecule-sec at 25 °C(2). These values correspond to atmospheric half-lives of about 6 to 67 days, at an atmospheric concentration of 5X10+8 nitrate radicals per cu cm(2). Trimethylbenzenes can also be degraded in the atmosphere by reaction with ozone molecules(3); however, this reaction is too slow to be of environmental relevance(3). Trimethylbenzenes are not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(4). Trimethylbenzenes do not contain chromophores that absorb wavelengths >290 nm(4) and therefore are not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of 1,2,3-trimethylbenzene with photochemically-produced hydroxyl radicals has been measured as 3.27X10-11 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 12 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of 1,2,3-trimethylbenzene with ozone has been measured as 1.6X10-21 cu cm/molecule-sec at 25 °C(2). This corresponds to an atmospheric half-life of about 20 years at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2). The rate constant for the vapor-phase reaction of 1,2,3-trimethylbenzene with nitrate radicals has been measured as 5.6X10-16 cu cm/molecule-sec at 25 °C(3). This corresponds to an atmospheric half-life of about 60 days and at an atmospheric concentration of 2.4X10+8 nitrate molecules per cu cm(4). 1,2,3-Trimethylbenzene is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(4).

BCF values ranging from 23 to 342 were measured in carp for trimethylbenzenes(1). According to a classification scheme(2), these BCF values suggest that bioconcentration in aquatic organisms is moderate to high(SRC).

The BCF of 1,2,3-trimethylbenzene was 133-217 at a concentration of 150 ppb and 136-259 at a concentration of 15 ppb using carp (Cypinus carpio) which were exposed over an 8-week period(1). According to a classification scheme(2), these BCFs suggest bioconcentration in aquatic organisms is high(SRC).

1,2,3-Trimethylbenzene has measured log Koc values of 3.04(1) and 2.80(2-5). These values correspond to Koc values of 1,096 and 630. 1,2,3-Trimethylbenzene also has a reported log Kom value of 2.80(6-7). According to a classification scheme(8), these Koc values suggest that 1,2,3-trimethylbenzene is expected to have low mobility in soil(SRC).

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.

Incineration /SRP: with appropriate emission controls/.

Incineration /SRP: with appropriate emission controls/. /Trimethyl benzenes/

This compound requires a shipping label of: "Flammable Liquid, Poison." It falls in DOT Hazard Class 3 and Packing Group III.

This compound requires a shipping label of: "Flammable Liquid, Poison." It falls in DOT Hazard Class 3 and Packing Group III. /Trimethyl benzenes/

UN Hazard Class: 3; UN Pack Group: III