SPECTRUM

Chemical Fact Sheet

Chemical Abstract Number (CAS #) 99650
CASRN 99-65-0
Synonyms1,3-DINITROBENENE
1,3-DINITROBENZOL
Molecular FormulaC6H4N2O4

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UseCHEM INT FOR: M-PHENYLENEDIAMINE, USED FOR ARAMID FIBERS, SPANDEX FIBERS; DYES; EXPLOSIVES [R1] USED FOR THE DETECTION OF 17-KETOSTEROID [R4] USED TO PREPARE AMINOCRESOLS BY ELECTROLYTIC REDUCTION [R5] USED AS AN INTERMEDIATE IN THE PRODUCTION OF AROMATIC AMINES /BY CATALYTIC REDUCTION WITH ELEMENTAL IRON IN HYDROCHLORIC ACID MEDIUM/ FOR DYE SYNTHESIS [R6] 97% of nitrobenzene is used to produce aniline, which has wide application in the manufacture of dyes, ... & medicines. /Nitrobenzenes/ [R7]
Apparent ColorYellowish ; Rhombohedral plates from alcohol, pale yellow solid
Boiling Point300-303 DEG C
Melting Point 89-90 DEG C
Molecular Weight 168.12
Misc CORROSIVITY: Liquid dinitrobenzene will attack some forms of plastics, rubber, and coatings. /Dinitrobenzene, all isomers/ DENSITY: 1.575 @ 18 DEG C/4 DEG C -696.8 kcal @ 20 deg C (solid) Log Kow= 1.49 SOLUBILITY: 1 G DISSOLVES IN 2000 ML COLD WATER, 320 ML BOILING WATER; 1 G DISSOLVES IN 37 ML ALCOHOL, 20 ML BOILING ALCOHOL; FREELY SOL IN CHLOROFORM, ETHYL ACETATE; VERY SOL IN ACETONE, HOT BENZENE & PYRIDINE; SOL IN ETHER; Water solubility: 2.2 mol/cu m MAX ABSORPTION (95% ETHANOL): 242 NM (LOG E= 4.21), 305 NM (LOG E= 3.04); IR: 4836 (Coblentz Society Spectral Collection); UV: 33 (Sadtler Research Laboratories Spectral Collection); NMR: 10134 (Sadtler Research Laboratories Spectral Collection); MASS: 127 (Aldermaston, Eight Peak Index of Mass Spectra, UK) 5.8 (air= 1 at boiling point of dinitrobenzene) /Dinitrobenzene, all isomers/ 5.13X10-6 atm (est) 1 mg/cu m= 0.14 ppm, 1 ppm= 6.99 mg/cu m SEVERE EXPLOSION HAZARD WHEN EXPOSED TO SHOCK OR FLAME The major hazards encountered in the use and handling of 1,3-dinitrobenzene stem from its toxicologic properties and explosivity. Toxic by all routes (ie, inhalation, ingestion, dermal absorption), exposure to this yellowish, crystalline substance may occur from its use in the production of analine, dyes, explosives, industrial solvents, and pesticides. Effects from exposure mayinclude contact burns to the skin and eyes, headache, nausea, lethargy, heart palpitations, methemoglobinemia, jaundice, and respiratory failure. Effects may be delayed up to 1-4 hours. OSHA has established an 8 hour, Time Weighted Average (TWA) limit of 1 mg/cu m, with a skin designation for this substance. In activities and situations where over-exposure may occur, wear a positive pressure self-contained breathing apparatus and chemical protective clothing which is specifically recommended by the shipper or manufacturer. If contact should occur, irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes and wash exposed skin thoroughly with soap and water. Contaminated clothing should be removed and discarded or left at the site for cleaning before being reworn. 1,3-Dinitrobenzene is a severe explosion hazard when exposed to friction, mechanical shock, localized thermal shock, or contamination. For fires involving 1,3-dinitrobenzene, extinguish with dry chemical, CO2, water spray, fog, or standard foam. Fight the fire from as far a distance as possible in an explosion-resistant location. If fire is massive, back off, protect surroundings, and let burn. 1,3-Dinitrobenzene may be transported via air, rail, road, and water, in containers bearing the label, "Poison." 1,3-Dinitrobenzene should be stored in a permanent magazine, away from heat, sources of ignition, sources of physical damage, oxidizers, combustibles, caustics, and metals such as tin and zinc. For small spills of 1,3-dinitrobenzene, use a clean shovel to place material into clean, dry, covered containers for later disposal (liquid solutions are taken up with sand or other noncombustible absorbent). Dike far ahead of large liquid spills to prevent runoff. Large dry spills should be covered with plastic sheeting. Large spills into bodies of water should be trapped at the bottom with sand bag barriers, apply activated carbon, and use mechanical dredges or lifts to remove immobilized masses. Health Hazards: Poisonous; may be fatal if inhaled, swallowed or absorbed through skin. Contact may cause burns to skin and eyes. Runoff from fire control or dilution water may cause pollution. /Dinitrobenzene; dinitrobenzene solution/ [R8] Fire or Explosion: Some of these materials may burn, but none of them ignites readily. May explode from friction, heat or contamination. /Dinitrobenzene; dinitrobenzene solution/ [R8] Emergency Action: Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind, out of low areas, and ventilate closed spaces before entering. Positive pressure self-contained breathing apparatus (SCBA) and chemical protective clothing which is specifically recommended by the shipper or manufacturer may be worn. It may provide little or no thermal protection. Structural firefighters' protective clothing is not effective for these materials. CALL CHEMTREC AT 1-800-424-9300 AS SOON AS POSSIBLE, especially if there is no local hazardous materials team available. /Dinitrobenzene; dinitrobenzene solution/ [R8] Fire: Small Fires: Dry chemical, CO2, water spray or regular foam. Large Fires: Water spray, fog or regular foam. Move container from fire area if you can do it without risk. Apply cooling water to sides of containers that are exposed to flames until well after fire is out. Stay away from ends of tanks. For massive fire in cargo area, use unmanned hose holder or monitor nozzles; if this is impossible, withdraw from area and let fire burn. /Dinitrobenzene; dinitrobenzene solution/ [R8] Spill or Leak: Do not touch or walk through spilled material; stop leak if you can do it without risk. Fully-encapsulating, vapor-protctive clothing should be worn for spills and leaks with no fire. Use water spray to reduce vapors. Small Spills: Take up with sand or other noncombustible absorbent material and place into containers for later disposal. Small Dry Spills: With clean shovel place material into clean, dry container and cover; move containers from spill area. Large Spills: Dike far ahead of liquid spill for later disposal. /Dinitrobenzene; dinitrobenzene solution/ [R8] First Aid: Move victim to fresh air and call emergency medical care; if not breathing give artificial respiration; if breathing is difficult, give oxygen. In case of contact with material, immediately flush skin or eyes with running water for at least 15 minutes. Speed in removing material from skin is of extreme importance. Remove and isolate contaminated clothing and shoes at the site. Keep victim quiet and maintain normal body temperature. Effects may be delayed; keep victim under observation. /Dinitrobenzene; dinitrobenzene solution/ [R8] Combustible [R9] Health: 3. 3= Materials extremely hazardous to health, but areas may be entered with extreme care. Full protective clothing, incl self-contained breathing apparatus, rubber gloves, boots and bands around legs, arms and waist should be provided. No skin surface should be exposed. /1,2-Dinitrobenzene/ [R10] Flammability: 1. 1= Materials that must be preheated before ignition can occur. Water may cause frothing of liquids ... if it gets below the surface of the liquid and turns to steam. ... water spray gently applied to the surface will cause a frothing which will extinguish the fire. /1,2-Dinitrobenzene/ [R10] Reactivity: 4. 4= Materials which in themselves are readily capable of detonation or of explosive decomposition or explosive reaction at normal temperatures and pressures. Includes materials which are sensitive to mechanical or localized thermal shock. If a chemical with this hazard rating is in an advanced or massive fire, the area should be evacuated. /1,2-Dinitrobenzene/ [R10] 302 DEG F (CLOSED CUP) [R11, 2457] Fire Fighting Respirator: Self-contained breathing apparatus with a full facepiece operated in pressure-demand or other positive pressure mode. [R12, 5] If /dinitrobenzene, solid/ is on fire, or involved in fire: Use water in flooding quantities as fog, and cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible, and use alcohol foam, carbon dioxide, or dry chemical. If fire is massive, back off, protect surroundings, and let burn. /Dinitrobenzene, solid/ [R13] FOR RESCUE PURPOSES WEAR FULL PROTECTIVE CLOTHING. FIGHT FIRE FROM AN EXPLOSION-RESISTANT LOCATION. IN ADVANCED OR MASSIVE FIRES, AREA SHOULD BE EVACUATED. IF FIRE OCCURS IN VICINITY OF THIS MATERIAL WATER SHOULD BE USED TO KEEP CONTAINERS COOL. [R10] EXPLOSION: SEVERE EXPLOSION HAZARD WHEN EXPOSED TO SHOCK OR FLAME [R14] Impact sensitivity (minimum fall of a 2 kg weight to cause at least one explosion in ten trial(s): > 100 cm. [R12, 2] REACTIVITY: Incompatible with tetranitromethane and nitric acid. [R15] Contact with strong oxidizers may cause fires and explosions. Contact with caustics and metals such as tin and zinc may cause evolution of heat and increase in pressure. [R12, 2] When heated to decomposition, it emits toxic fumes of nitrates. [R15] Eyes are irritated by liquid. [R16] Employees should be provided with and required to use impervious clothing, gloves, face shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent skin contact with dinitrobenzene or liquids containing dinitrobenzene. /SRP: Liquid dinitrobenzene will attack some forms of plastics, rubber, and coatings./ [R12, 3] Respiratory protection for dinitrobenzene (all isomers): Minimum respiratory protection required above 1 mg/cu m: Particulate concentration: 5 mg/cu m or less: Any dust and mist respirator, except single-use. 10 mg/cu m or less: Any dust and mist respirator, except single-use or quarter-mask respirator, or any fume respirator or high efficiency particulate filter respirator, or any supplied-air respirator, or any self-contained breathing apparatus; 50 mg/cu m or less: A high efficiency particulate filter respirator with a full facepiece, or any supplied-air respirator with a full facepiece, helmet, or hood, or any self-contained breathing apparatus with a full facepiece; 200 mg/cu m or less: A powered air-purifying respirator with a high efficiency particulate filter, or A type C supplied-air respirator operated in pressure-demand, or other positive-pressure or continuous-flow mode; Greater than 200 mg/cu m or entry and escape from unknown concentrations: Self-contained breathing apparatus with a full facepiece operated in pressure-demand or other positive pressure mode, or a combination respirator which includes a type C supplied-air respirator with a full facepiece operated in pressure-demand or other positive pressure or continuous-flow mode and an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive pressure mode. Escape: Any dust and mist respirator, except single-use, or any escape self-contained breathing apparatus. [R12, 5] Eating and smoking should not be permitted in areas where dinitrobenzene or liquids containing dinitrobenzene are handled, processed, or stored. Employees who handle dinitrobenzene or liquids containing dinitrobenzene should wash their hands thoroughly with soap or mild detergent and water before eating, smoking, or using toilet facilities. [R12, 3] Protect containers against physical damage. Keep away from heat and sources of ignition or acute fire hazard area. Storage area should be equipped with an automatic sprinkler system if within a building. [R17] Clothing contaminated with dinitrobenzene should be placed in closed containers for storage until it can be discarded or until provision is made for the removal of dinitrobenzene from the clothing. [R12, 3] If employees' clothing becomes contaminated with solid dinitrobenzene, employees should change into uncontaminated clothing before leaving the work premises. ... If the clothing is to be laundered or otherwise cleaned to remove the dinitrobenzene, the person performing the operation should be informed of dinitrobenzene's hazardous properties. [R12, 3] Where exposure of an employee's body to liquids containing dinitrobenzene may occur, facilities for quick drenching of the body should be provided within the immediate work area for emergency use. [R12, 3] Non-impervious clothing which becomes contaminated with liquids containing dinitrobenzene should be removed immediately and non-impervious clothing which becomes contaminated with dinitrobenzene should be removed promptly and such clothing should not be reworn until the dinitrobenzene is removed from the clothing. [R12, 3] Good industrial hygiene practices recommend that engineering control be used to reduce environmental concentrations to the permissible exposure level. However, there are some exceptions where respirators may be used to control exposure. Respirators may be used when engineering and work practice controls are not technically feasible, when such controls are in the process of being installed, or when they fail and need to be supplemented. Respirators may also be used for operations which require entry into tanks or closed vessels, and in emergency situations. If the use of respirators is necessary, the only respirators permitted are those that have been approved by the Mine Safety and Health Administration (formerly Mining Enforcement and Safety Administration) or by the National Institute for Occupational Safety and Health. [R12, 2] In addition to respirator selection, a complete respiratory protection program should be instituted which includes regular training, maintenance, inspection, cleaning, and evaluation. [R12, 2] If /dinitrobenzene, solid/ is not on fire and not involved in a fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. /Dinitrobenzene, solid/ [R13] Personnel protection: Avoid breathing dusts and fumes from burning material. Keep upwind, avoid bodily contact with the material. Wear full protective clothing, do not handle broken packages without protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water, and wear positive pressure self-contained breathing apparatus when fighting fires involving this material. [R13] Contact lenses should not be worn when working with this chemical. /Dinitrobenzene (all isomers)/ [R18, 111] The scientific literature supports the wearing of contact lenses in industrial environments, as part of a program to protect the eye against chemical compounds and minerals causing eye irritation. 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. SHIPPING: No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./ [R19] Domestic Transportation: Chemical: Dinitrobenzene, solid or solution. Primary Hazard Class: Poison B. A poison B is a substance that is known to be toxic to humans and poses a severe health hazard if released during transportation. UN 1597. Label(s) required: Poison. Acceptable Modes of Transportation: Air, rail, road, and water. /Dinitrobenzene, solid or solution/ [R20] Int'l Air Shipments: Chemical: Dinitrobenzenes. IMO Class: 6.1. UN 1597. Primary hazard label: Poison (packaging group II). Additional packaging instructions listed in the table must also be followed. /Dinitrobenzenes/ [R21] International Water Shipments: Chemical: Dinitrobenzenes. IMO Class: 6.1, poisons. UN 1597. Packaging Group: II. Label(s) required: Poison. /Dinitrobenzenes/ [R22] STORAGE: STORE ONLY IN PERMANENT MAGAZINE. THIS HIGH EXPLOSIVE SHOULD BE KEPT WELL AWAY FROM INITIATOR EXPLOSIVES; PROTECTED FROM PHYSICAL DAMAGE; SEPARATED FROM OXIDIZING MATERIALS, COMBUSTIBLES, & SOURCES OF HEAT. /1,2-DINITROBENZENE/ [R10] CLEANUP: 1. Remove all ignition sources. 2. Ventilate area of spill. 3. For small quantities, sweep onto paper or other suitable material & burn in a suitable combustion chamber which allows burning in an unconfined condition & is equipped with an appropriate effluent gas cleaning device. Large quantities may be reclaimed; however, if this is not practical, dissolve in fuel oil & atomize in a suitable combustion chamber equipped with an appropriate effluent gas cleaning device. [R12, 4] Environmental considerations: land spill; Dig a pit, pond, lagoon, or holding area to contain liquid or solid material /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner/. Cover solids with a plastic sheet to prevent dissolving in rain, or fire fighting water. Environmental considerations: water spill: Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom; If dissolved in region of 10 ppm or greater concentration, apply activated carbon at ten times the spilled amount, or use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. Environmental considerations: air spill; Apply water spray or mist to knock down vapors. Vapor knock down water is corrosive or toxic and should be diked for containment. /Dinitrobenzene, solid/ [R13] DISPOSAL: 1. By making packages of dinitrobenzene in paper or other flammable material & burning in a suitable combustion chamber which allows burning in an unconfined condition & is equipped with an appropriate effluent gas cleaning device. 2. By dissolving dinitrobenzene in fuel oil & atomizing in a suitable combustion chamber equipped with an appropriate effluent gas cleaning device. [R12, 4] Dissolve in combustible solvent such as alcohols, benzene, etc. Spray the solution into the furnace with afterburner and scrubber. [R17] The following wastewater treatment technologies have been investigated for dinitrobenzene: Concentration process: Reverse osmosis. /Dinitrobenzene/ [R23] A complete history and physical examination /should be performed/ to detect existing conditions that might place the exposed employee at increased risk, and to establish a baseline for future health monitoring. Examination of the blood, liver, cardiovascular system, and eyes should be stressed. [R12, 1] A complete blood count: Dinitrobenzene has been shown to cause methemoglobinemia. ... A complete blood count should be performed, including a red cell count, a white cell count, a differential count of a stained smear, as well as hemoglobin and hematocrit. Observe for Heinz bodies. ... Liver function tests: Since liver damage has been observed in humans exposed to dinitrobenzene, a profile of liver function should be performed by using a medically acceptable array of biochemical tests. [R12, 1] IN CASES OF CHRONIC POISONING, IMPAIRMENT OF VISION APPEARS TO HAVE BEEN COMMON. ... VISUAL FIELDS ... SLIGHTLY CONTRACTED, & VISUAL ACUITY ... REDUCED, WITH CENTRAL SCOTOMAS, PARTICULARLY FOR RED & GREEN. USUALLY THERE HAS BEEN NO ABNORMALITY IN APPEARANCE OF THE OPTIC NERVEHEAD OTHER THAN SLIGHT PALLOR ... PARTIAL OPTIC ATROPHY ... VISION HAS GRADUALLY RECOVERED. /DINITROBENZENE/ [R2, 356] SURFACE CONTACT MAY CAUSE YELLOWING OF SKIN, & PURPORTEDLY OF CONJUNCTIVA & CORNEA ... SKIN, CONJUNCTIVA, & OCULAR FUNDUS MAY SHOW BLUISH DISCOLORATION ... /DINITROBENZENE/ [R2, 355] CHRONIC POISONING ... FOLLOWING EXPOSURE FOR 9 TO 18 MO TO DUST & VAPOR IN MUNITIONS PLANTS. SYMPTOMS ... START WITH HEADACHE, & BURNING PAIN & PARESTHESIA IN FEET, ANKLES, HANDS, & FOREARMS. ... APATHY & TIREDNESS, SHORTNESS OF BREATH & PALPITATION OF HEART. PERIPHERAL NERVE DISTURBANCES HAVE ALL BEEN SENSORY ... VISION HAS BEEN AFFECTED ... . /DINITROBENZENE/ [R2, 355] NITRO CMPD OF DINITROBENZENE ... TYPE HAVE HISTORY OF PROMINENT HEPATOTOXIC EFFECTS ... HEPATIC INJURY IS MANIFESTED BY JAUNDICE ... DEMONSTRABLE IN CONJUNCTIVAE ... POTENT METHEMOGLOBIN PRODUCER ... CYANOSIS PROVIDES WARNING OF EXPOSURE ... /DINITROBENZENE/ [R24] A case of acute intoxication caused by exposure to m-dinitrobenzene dust that occurred in 1969 was reported. The workers developed cyanosis which was followed by a slight to moderate anemia, 1.9-15.5% loss in specific gravity of the whole blood. Prolonged recovery from the anemia was a characteristic of the intoxication cases. All workers exposed to the chemical had been followed for ten years and it was confirmed that there was no long term adverse effect attributable to the exposure. [R25] META ISOMER IS SAID TO BE MOST IMPORTANT TOXICOLOGICALLY, ESP AS METHEMOGLOBIN FORMER. /DINITROBENZENE/ [R26] Methemoglobinemia, cyanosis and symptoms of hemolytic anemia have been observed in individuals exposed to m-dinitrobenzene by the inhalation and cutaneous routes. [R27] Repeated or prolonged exposure to dinitrobenzene may cause anemia. /Dinitrobenzene/ [R12, 1] Dinitrobenzene may affect the ability of blood to carry oxygen. /Dinitrobenzene/ [R12, 1] METHEMOGLOBIN-FORMING CAPACITY IN CAT. MOLECULAR RATIO (MOLAR RATIO OF METHEMOGLOBIN FORMED TO DOSE OF TEST CMPD): 6.4-7.8. [R11, 2417] Rats were injected ip with 0.015 umol of p-dinitrobenzene/kg, 0.15 umol of m-dinitrobenzene/kg and 0.45 umol of o-dinitrobenzene/kg body wt. The dinitrobenzenes induced methemoglobin concentrations of 86%, 60% and 49%, respectively, and increases of urinary catecholamine excretion and blood sugar concentration. Due to hyperglycemia the glycolysis may be stimulated as mechanism for energy production in methemoglobin-induced oxygen deficiency and as mechanism for reduction of methemoglobin, that means as responses favoring survival after poisoning. [R28] Studies in normal and antibiotically-treated rats in vivo examining the methemoglobinemia-inducing capacity of nitro-compounds, indicated that methemoglobinemia induction and nitroreduction could occur independently of the gastrointestinal microflora. In vitro incubations with rat blood suggested that in some cases the conversion of hemoglobin to methemoglobin could occur possibly as a result of a direct interaction between unchanged nitro cmpd and hemoglobin. [R29] When 1,3-dinitrobenzene was given to rats orally as a 1% suspension in corn oil, the LD50 was 83 mg/kg with fiducial limits 56-124 mg/kg. The cmpd was equally toxic in both sexes. Signs of toxicity included reduction in ambulatory motion, ataxia, weakness, dyspnea, rapid heartbeat, cyanosis, coma and respiratory failure. When 1,3-dinitrobenzene was added to the daily drinking water in concn of 50, 100 and 200 mg/l for 8 wk, 3 of 6 male rats receiving the highest concn died during wk 4 and another died during wk 5. In females, one died during wk 6 and another during wk 7. All other animals survived. Growth rate was reduced in both sexes and at 200 mg/l 1,3-dinitrobenzene in the water supply the animals lost weight. There were mild, consistent reductions in hematocrit and hemoglobin values. Enlarged spleens were present in both sexes at all concn; fibrosis with deposition of hemosiderin was present in all rats at 200 mg/l 1,3-dinitrobenzene. Testicular atrophy was evident but there was no effect on the ovaries. A brown-yellow pigment was deposited in the Kupffer cells of the liver. Hexobarbital-induced sleep time decr. When 3, 8, or 20 mg/l 1,3-dinitrobenzene was provided daily in drinking water for 16 wk, no signs of acute toxicity were seen. [R30] TOXICITY THRESHOLDS FOR 1,3-DINITROBENZENE USING THE CELL MULTIPLICATION INHIBITION TEST WAS DETERMINED FOR PSEUDOMONAS PUTIDA (BACTERIA), SCENDESMUS QUADRICAUDA (GREEN ALGAE) & ENTOSIPHON SULCATUM (PROTOZOA). TOXICITY THRESHOLDS WERE 14 MG/L, 0.7 MG/L, & 0.76 MG/L, RESPECTIVELY. TEST WAS BASED ON PRINCIPLE THAT DISSOLVED TOXIC WATER INGREDIENTS WILL INHIBIT MULTIPLICATION OF TEST ORGANISMS AS COMPARED TO CULTURE FREE FROM SUCH INFLUENCE. [R31] The acute toxicities of nitro-compounds, incl dinitrobenzene, were evaluated in fathead minnows (Pimephales promelas). Compounds with nitro groups positioned ortho or para to each other were appreciably more toxic than isomers having the nitro groups in the meta orientation. [R32] m-Dinitrobenzene was mutagenic in Salmonella typhimurium TA98 without S-9 mix. Melting temp of calf thymus DNA was elevated by addn of m-dinitrobenzene. [R33] Weanling male Sprague-Dawley rats were gavaged 5 dy/wk with 1,3-dinitrobenzene at doses of 0, 0.75, 1.5, 3.0, and 6.0 mg/kg/dy. Males were bred to untreated females during treatment wk 10 and were killed during treatment wk 12. Although males dosed with 3 mg/kg/dy inseminated the females and evidence of mating was observed in males dosed with 6 mg/kg/dy, none of the males in these groups sired litters. Diminished sperm production (reduced testicular sperm head counts), decreased cauda epididymal sperm reserves, nonmotile spermatozoa, atypical sperm morphology, decreased weights of the testes and epididymides, seminiferous tubular atrophy, and incomplete spermatogenesis were also observed in these males. Sperm production was also decreased in males dosed with 1.5 mg/kg/dy. Changes in the spleen included increased weight at dosages of 1.5 mg/kg/dy or higher and splenic hemosiderosis, which ranged from slight in rats treated with 0.75 mg/kg/dy to moderately severe in those dosed with 6 mg/kg/dy. The data indicate that 1,3-dinitrobenzene is a potent testicular toxicant in the male rat, capable of producing extensive damage to reproductive tissues and reproductive failure. Limited data on four rats that received 6 mg/kg/dy and were allowed a 5 month post treatment recovery period suggested that the testicular effects are partially reversible. [R34] Nitrobenzene increases methemoglobin formation when incubated with native hemoglobin but not when incubated with (rat) red blood cell suspensions. Transport of nitrobenzene across the red blood cell membrane may be a limiting factor for methemoglobin production by red blood cell suspensions. Incubation of (14)C-m-, o- or p-dinitrobenzene, but not mononitrobenzene, with red blood cell suspensions caused a time-dependent increase in methemoglobin. All 3 dinitrobenzenes and mononitrobenzene crossed the red blood cell membrane and accumulated in the erythrocytes within 1 min of incubation. Incubation of mononitrobenzene with hemolysates did not result in methemoglobin production. The dinitrobenzenes or mononitrobenzene do not enter the red blood cell by an active process. Dinitrobenzene-induced methemoglobin production was markedly inhibited at 4 deg C, and may be a result of deceased interaction with hemoglobin and/or decreased metabolism to reactive intermediates which mediate methemoglobin production. [R35] Male F-344 rats were given a single oral or ip dose of 20 or 25 mg/kg of 1,3-dinitrobenzene or split ip doses of two 10 mg treatments (separated by a four hr interval) daily. Rats were divided into the following groups of six individuals each: conventional, germ-free, and germ-free repopulated with suspensions of bacteria. After an oral dose of 25 mg/kg, the formation of methemoglobin with time was similar for conventional and germ-free rats. Administration of a single oral dose of 20 mg/kg resulted in ataxia in 4/6 germ-free rats, but not in conventional or germ-free repopulated rats administered 25 mg/kg. Repeated oral dosings (5 days x 20 mg/kg/day) were necessary for ataxia in 6/6 conventional rats. All germ-free rats died after a single ip dose of 20 mg/kg whereas conventional rats given 25 mg/kg ip survived and showed no ataxia up to 24 hr after injection. When administered (14)C-labeled 1,3-dinitrobenzene, whole blood, plasma, liver, kidney, testis, sciatic nerve, white and brown fat, and brain stem of germ-free rats had higher concentrations of radioactivity than the respective tissues of conventional rats. Following administration of a single po dose of 25 mg/kg, whole blood of conventional rats had a peak mean concentration of the parent compound of 4.2 ug/ml at 0.5 hr. Half-life was approximately 10 hr. In germ-free rats the peak concentration was 7.5 ug/ml after 0.5 hr (maintained for 6 hr); half-life was 20 hr. Neurotoxic lesions were observed in the brain stem and inferior colliculus of treated rats. The well-defined damage was confined to the lateral vestibular nucleus, medial vestibular nucleus, cerebellar roof nucleus, the superior olives and lateral cochlear nucleus. Animals with well-defined lesions did not necessarily show ataxia. Lesions resembled those of thiamine deficiency in rats. Glucose concentration in the CNS of both conventional and germ-free rats was similar; lactate in the lateral vestibular nucleus and inferior colliculus of germ-free rats was increased. [R36] Reproductive toxicology experiments were performed employing 1,3-dinitrobenzene treatment of male B6C3F1/J mice. The effects of exposure were determined on adult, prepubertal, and pubertal aged mice. Adults and pubertal mice were exposed to 8, 16, 32, or 48 mg/kg m-DNB, and prepubertal mice to 40 or 48 mg/kg. Measurements were taken over days 1 through 25 post treatment. Significant effects on testicular function were noted only at the 48 mg/kg dose level. No effect was noted on body or testis weight except for reduced adult mouse testis weights at 22 days post treatment at the 48 mg/kg level. No detectable levels of germinal epithelial cells were noted in the ductus epididymis. Only nominal nonsignificant changes were noted in the relative percent of testicular cell types for the prepubertal and pubertal mouse groups. Adult mice testicular cell type ratios changed significantly at 48 mg/kg dose levels. A reduction in the percent tetraploid cells occurred on day one, suggesting these cells may be a primary target of m-DNB activity. No increased susceptibility to DNA denaturation was noted in caput and caudal sperm from mice exposed prior to puberty. In pubertal mice exposure further exaggerated the abnormal chromatic structure which normally characterizes sperm during the onset of sperm production. Exposure in adult mice increased susceptibility to DNA denaturation of caput sperm chromatic and caudal sperm. The effects of exposure on testicular function were less pronounced in the pubertal and prepubertal mice than in adults. [R37] An investigation was performed to determine whether flow cytometric analysis methods previously used to characterize mouse germ cells could be used to determine the toxic effects of 1,3-dinitrobenzene in rats. Sixty day old male Sprague-Dawley rats were divided into five treatment groups and exposed to m-DNB at levels of 0, 8, 16, 32, or 48 mg/kg by oral intubation. Four animals from each dosage group were sacrificed on days one, four, 16, and 32 post treatment. The findings indicated that m-DNB exerted a very strong toxic effect on male rat reproductive function. One day after a single exposure to 48 mg/kg dose levels, measurements of caput epididymal fluid cells indicated the presence of testicular germinal epithelial cells which had apparently sloughed off into the epididymis. A decrease was also noted in pachytene spermatocytes. Testicular damage by day 16 after exposure to 32 or 48 mg/kg doses indicated alterations of cell type ratios. Extensive recovery of cell type ratios occurred by 32 days post treatment. Changes were noted in sperm chromatin structure at 16 days post exposure to 32 and 48 mg/kg. A dose/response increase in percent sperm head morphology abnormalities was assessed in cauda epididymal and vas sperm. [R38] LD50 Rat oral as a 1% suspension in corn oil 83 mg/kg with fiducial limits 56-124 mg/kg [R30] Those with blood disorders may be at increased risk. [R12, 1] It is readily absorbed through the skin, either as solid, liquid or vapor. [R12] Male F-344 rats were given a single oral or ip dose of 20 or 25 mg/kg of 1,3-dinitrobenzene or split ip doses of two 10 mg treatments (separated by a four hr interval) daily. Rats were divided into the following groups of six individuals each: conventional, germ-free, and germ-free repopulated with suspensions of bacteria. After an oral dose of 25 mg/kg, the formation of methemoglobin with time was similar for conventional and germ-free rats. ... When administered (14)C-labeled 1,3-dinitrobenzene, whole blood, plasma, liver, kidney, testis, sciatic nerve, white and brown fat, and brain stem of germ-free rats had higher concentrations of radioactivity than the respective tissues of conventional rats. Following administration of a single oral dose of 25 mg/kg, whole blood of conventional rats had a peak mean concentration of the parent compound of 4.2 ug/ml at 0.5 hr. Half-life was approximately 10 hr. In germ-free rats the peak concentration was 7.5 ug/ml after 0.5 hr (maintained for 6 hr); half-life was 20 hr. ... [R36] ... METABOLIZED ... BY REDN OF 1 OR BOTH NITRO GROUPS, & BY HYDROXYLATION OF BENZENE RING, TO PRODUCE DINITRO-, AMINONITRO-, & DIAMINOPHENOLS. AFTER FEEDING M-DINITROBENZENE (LABELLED WITH (14)CARBON) TO RABBITS THE METABOLITES PRESENT IN THE URINE WERE M-NITROANILINE ... M-PHENYLENEDIAMINE ... 2-AMINO-4-NITROPHENOL ... 4-AMINO-2-NITROPHENOL & 2,4-DIAMINOPHENOL. ... THE ABSENCE OF ANY 3,5-SUBSTITUTED PHENOLS SUGGESTS THAT REDN OF 1 OF NITRO GROUPS PRECEDES HYDROXYLATION. [R39] The biotransformation of m-dinitrobenzene was studied in rabbits. The animals recieved a single oral dose of radiocarbon-labeled m-DNB in the range of 50 to 100 mg/kg. Urine was collected for two days after dosing for analysis of metabolites. Over the two day period, more than 80% of the radiolabel was excreted in the urine; feces contained between 0.3 and 5.2% of the radioactive dose. m-DNB underwent extensive biotransformation. The major urinary metabolites were 2,4-diaminophenol (31% of the dose), m-nitroaniline and m-phenylenediamine (together, 35% of the dose), and 2-amino-4-nitrophenol (24%). [R40] The redn of aromatic nitro compounds was investigated in purified milk xanthine oxidase system. ... The redn rate was greatest for p-substitution of electron-withdrawing groups, and for m-substitution of electron-repelling groups, respectively. [R41] Nitroreductase activity was previously known to occur under nitrogen atmosphere in the cytosolic and microsomal fractions of liver homogenates. This study describes a subcellular nitroreductase activity which occurs in liver mitochondria under aerobic conditions. Mitochondria were isolated from rat liver and assayed for their capacity to reduce certain nitro compounds by measuring spectrophotometrically both the appearance of amino compounds and the consumption of nicotinamide adenine dinucleotide. Intact mitochondria were found to possess a p-dinitrobenzene reductase activity. The activity was destroyed by heat, and was present at only 20% in the microsomal fraction. It was strictly nicotinamide adenine dinucleotide-dependent, while only little or no activity occurred with reduced nicotinamide adenine dinucleotide or other oxidative substrates. Nitro reduction was inhibited by thiol reagents. Rat liver mitochondria showed about 15% activity with o-dinitrobenzene and m-dinitrobenzene, while there was less than 5% activity with a series of p-nitro compounds including chloramphenicol. [R42] The metabolism of radiolabeled dinitrobenzene isomers was compared in hepatocytes and hepatic subcellular fractions isolated from male Fischer-344 rats. Under aerobic conditions, reduction was the major metabolic pathway for m- and p-dinitrobenzene in hepatocytes with m- and p-nitroaniline accounting for 74.0 + or - 1.2% and 81.0 + or - 0.6% (mean + or - standard error, n= 4), respectively, of the radioactivity present after a 30 min incubation. The major metabolite of o-dinitrobenzene in similar incubations was S-(2-nitrophenyl)glutathione which represented 48.1 + or - 5.5% of the total radioactivity; o-nitroaniline accounted for 29.5 + or - 2.1% of the radioactivity. Incubation of dinitrobenzenes with microsomes produced nitroanilines as well as nitrosonitrobenzenes and nitrophenylhydroxylamines. Reduction of o- and m-dinitrobenzene by microsomes was reduced nicotinamide adenine dinucleotide-dependent. Reduction of p-dinitrobenzene could be supported by nicotinamide adenine dinucleotide as well as reduced nicotinamide adenine dinucleotide, although the rate of reduction was slower with nicotinamide adenine dinucleotide. Conjugation of o- and p-dinitrobenzene, but not m-dinitrobenzene, with glutathione occurred in cytosol incubations although only o-dinitrobenzene formed the glutathione conjugate in intact hepatocytes. [R43] Dinitrobenzene may affect the ability of blood to carry oxygen. [R12, 1] Rats were injected ip with 0.015 umol of p-dinitrobenzene/kg, 0.15 umol of m-dinitrobenzene/kg and 0.45 umol of o-dinitrobenzene/kg body wt. ... Due to hyperglycemia the glycolysis may be stimulated as mechanism for energy production in methemoglobin-induced oxygen deficiency and as mechanism for reduction of methemoglobin, that means as responses favoring survival after poisoning. [R28] IN SUBACUTE POISONING, SYMPTOMS MAY BE PRECIPITATED BY SUNLIGHT OR BY INGESTION OF ALCOHOL. /DINITROBENZENE/ [R26] Release of 1,3-dinitrobenzene may result from its use as an intermediate in organic synthesis and in the production of dyes. Release of 1,3-dinitrobenzene to soil is expected to result in adsorption to clay but adsorption to other soils is expected to be weak and leaching may occur. Volatilization from soil surfaces may occur but is expected to be slow. Reduction to aromatic amines may occur under anaerobic conditions. Release of 1,3-dinitrobenzene to water may result in biodegradation and slow volatilization from the water surface. Direct photolysis may occur based on its absorption of UV light greater than 290 nm. Bioconcentration and hydrolysis are not expected to be significant fate process. Release of 1,3-dinitrobenzene to the atmosphere is expected to result in the reaction of 1,3-dinitrobenzene with photochemically generated hydroxyl radicals with an estimated half-life of 14.15 hr. Direct photolysis may also occur. (SRC) Dinitrobenzene is one of the many nitroaromatic compounds which are used in the manufacture of dyes, explosives, industrial solvents, and pesticides and thus, may be released to the environment as a result of such uses(1). 1,3-Dinitrobenzene has been detected in the discharges of a munitions plant(2). Due to its presence in commercial TNT, it may also be released to the environment from munitions blending and loading operations(2). Photolysis of 2,4-dinitrotoluene (a munition by-product found in effluent) can result in 1,3-dinitrobenzene presence in the environment(2). [R44] TERRESTRIAL FATE: 1,3-Dinitrobenzene is expected to adsorb strongly to clay but only weakly to other soils from which 1,3-dinitrobenzene may leach to groundwater. Biodegradation may be significant. Reduction to aromatic amines may occur under anaerobic conditions. Volatilization from the soil surface may occur but is expected to be slow. (SRC) AQUATIC FATE: 1,3-Dinitrobenzene may biodegrade in water and volatilization may occur, but is expected to be slow. Direct photolysis may occur, but a rate cannot be estimated using the available information. Bioconcentration and hydrolysis are not expected to be significant because of low estimated bioconcentration factors and the lack of hydrolyzable groups, respectively. (SRC) ATMOSPHERIC FATE: The half-life for the reaction of vapor phase 1,3-dinitrobenzene with photochemically generated hydroxyl radicals in the atmosphere was estimated to be 14.15 hr(1). Direct photolysis may occur, but a rate cannot be estimated using the available information(SRC). [R45] Anaerobic and aerobic incubation of 1,3-dinitrobenzene with sewage effluent at 29 deg C resulted in about 85% and 40% degradation after 28 days, respectively, as determined by absorbance measurements(1). The products of the anaerobic incubations were aromatic amines while under aerobic conditons, ring cleavage and possible mineralization of the 1,3-dinitrobenzene occurred(1). More than 64 days were required to achieve a total loss of ultraviolet absorbancy of 1,3-dinitrobenzene when incubated with Niagara silt loam at 25 deg C (2). 1,3-Dinitrobenzene was incubated in Tennessee River water at 25 deg C(3). A second order rate constant of 3.7X10-8 ml 1/CFU (colony forming units) hr was obtained from the biodegradation data and was used to estimate a half-life of about 1 day(3). After 3 hr incubation at 30 deg C with phenol adapted bacteria from soil and related environments, 75% of the initial amount of 1,3-dinitrobenzene was degraded(4). [R46] No data were available concerning the hydrolysis, photolysis or photooxidation of 1,3-dinitrobenzene. 1,3-Dinitrobenzene may directly photolyze based on its absorbance of light of greater than 290 nm(1). 1,3-Dinitrobenzene is not expected to hydrolyze under environmental conditions since no functional groups that hyrolyze are available(1). [R47] The log bioconcentration factor (BCF) of 1,3-dinitrobenzene in trout muscle is 0.93(1). Using a log octanol/water partition coefficient of 1.49(2), a log BCF of 0.9024 was estimated(3). Bioconcentration factors of these magnitudes suggest that bioconcentration of 1,3-dinitrobenzene fish will not be significant(SRC). [R48] Using a log octanol/water partition coefficient of 1.49(1), a log soil-sorption coefficient (Koc) of 1.39 was estimated(2,SRC). A Koc of this magnitude suggests that 1,3-dinitrobenzene will not strongly sorb to soils(3) and may, therefore, leach. It has been shown, however, that p-nitrophenol adsorbs to clay through an interaction between the nitro group and the water molecules or metallic cations in the clay (4), and 1,3-dinitrobenzene may similarly bind to clays. Therefore, in these soils, 1,3-dinitrobenzene may not leach to groundwater(SRC). [R49] The water solubility of 1,3-dinitrobenzene is 2.2 mol/cu m and the estimated vapor pressure is 5.13X10-6 atm(1). These values were used to estimate a Henry's Law constant of 2.33X10-6 atm-cu m/mole(1). The estimated Henry's Law constant of 1,3-dinitrobenzene suggests that volatilization of this compound from water will be slow(2). [R50] The concentration of 1,3-dinitrobenzene in an extract of effluent water from organics and plastics industries was 1055 ng/ul(1). [R51] Inhalation; Skin absorption; Ingestion; and Skin and/or eye contact. [R52] 200 mg/cu m /Dinitrobenzene, all isomers/ [R18, 110] OSHA: 8 hr Time-Weighted avg: 1 mg/cu m. Skin absorption designation. /Dinitrobenzene, all isomers/ [R53] +8 Hr Time Weighted Avg (TWA) 0.15 ppm, 1.0 mg/cu m, skin (1986) /Dinitrobenzene, all isomers/ [R54, 20] +Excursion Limit Recommendation: Excursions in worker exposure levels may exceed three times the TLV-TWA for no more than a total of 30 min during a work day, and under no circumstances should they exceed five times the TLV-TWA, provided that the TLV-TWA is not exceeded. /Dinitrobenzene, all isomers/ [R54, 5] +Biological Exposure Index (BEI) adoption (1990-91 edition): Methemoglobin in blood during or end of shift is 1.5% of hemoglobin. The determinant is usually present in a significant amt in biological specimens collected from subjects who have not been occupationally exposed. Such background levels are incl in the BEI value. The determinant is nonspecific, since it is observed after exposure to some other chemicals. These nonspecific tests are preferred because they are easy to use and usually offer a better correlation with exposure than specific tests. In such instances, a BEI for a specific, less quantitative biological determinant is recommended as a confirmatory test. The biological determinant is an indicator of exposure to the chemical, but the quantitative interpretation of the measurements is ambiguous. /Methemoglobin inducers/ [R54, 58] Czechoslovakia, East & West Germany, Sweden, & USSR: 0.15 ppm (no date) [R55] Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). [R56] Amberlite XAD-2 and XAD-7 porous polymers were evaluated for the solid sampling of aliphatic and aromatic nitro cmpd in workroom air. With the use of solvent desorption, XAD-2 gave 80-100% recovery of nitroaromatics, and XAD-7 85-100% recovery of nitroaliphatics. The cmpd studied included m-dinitrobenzene. [R57] NIOSH Method S214. Analyte: Dinitrobenzene. Matrix: Air. Procedure: Filter and bubbler collection, ethylene glycol extraction. Flow Rate: 1-5 liter/min. Sample Size: 90 liters. /Dinitrobenzene/ [R58, S214-1] A simple procedure has been developed for the determination of munitions present in water at levels as low as 0.1 ug/liter. The method uses 60-80 mesh XAD-4 for extraction, followed by elution with 20 ml of ethyl acetate, concentration of the eluate, separation by capillary gas chromatography, and detection using electron capture. [R59] NIOSH Method S214. Analyte: Dinitrobenzene. Matrix: Air. Procedure: High pressure liquid chromatography. Method Evaluation: Method was validated over the range of 0.418 to 2.386 mg/cu m using a 90 liter sample. Precision (CVt): 0.091. Applicability: Under the conditions of sample size (90 liters) the useful range is 0.42 to 2.4 mg/cu m. /Dinitrobenzene/ [R58, S214] EPA Method 8090. Gas Chromatographic Method for the detection of ppb levels of nitroaromatic and cyclic ketone compounds. Detection is achieved by an electron capture detector (ECD) for dinitrotoluenes or a flame ionization detector (FID) for the other compounds amenable to this method. The method detection limit of dinitrobenzene is not given. Precision and method accuracy were found to be directly related to the concentration of the analyte and essentially independent of the sample matrix. /Dinitrobenzene/ [R60]

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