1,3 DINITROBENZENE (BNB) PROFILE OF DRINKING WATER CONTAMINANTS FOR EMERGENCY RESPONSE GENERAL INFORMATION 1,3-Dinitrobenzene (DNB) is a by-product in the manufacture of trinitrotoluene (TNT) explo- sives and nitrobenzene. It is used primarily in the production of m-phenylenediamine; a dye intermediate. Production in the United States takes place mainly at one commercial plant in New Jersey where the 1983 production was reported to be 70,000 to 72,000 pounds. DNB occurs in the waste stream from TNT production and in waste- waters from dinitrobenzene manufacturing. It is also released to the atmosphere. The environmental fate of DNB is not known, but in general, aromatic nitro compounds are resistant to hydrolysis and probably do not oxidize in water. DNB is not expected to bioaccumulate in aquatic organisms. Prelimi- nary indications are that photolytic degradation may be an important fate while volatilization is not Microbial degradation occurs in waste streams. PHARMACOKINETICS . Inhalation and dermal absorption have been inferred from occupational exposures. Absorp- tion of oral doses of DNB by rats and rabbits is 63-93%. DNB is distributed mainly to liver, fat, kidney, and nerve tissues and excreted primarily In the urine. Metabolism to the nitroanilines is the major metabolic pathway. HEALTH EFFECTS Humans After occupational exposure to DNB dust (con- centration unknown), six workers developed cyanosis, anemia, dizziness, and fatigue. Cyanosis and hemolytic jaundice were seen in another worker that was thought to have received dermal exposure of DNB. Formation of methemoglobin and urinary excretion of 2,4-dfnitrophenoJ were ob served in the worker. HEALTH EFFECTS Experimental Animals Acute toxicity in rats is associated with respi- ratory failure, central nervous system distur- bances including ataxia, motor dysfunction, and coma, and testicular damage and infertility. No studies of potential dermal sensitization are available. Drinking water studies in rats for 8 and 16 weeks showed decreased splenic and testicular weights and decreased spermatogenesis. Effects reported from a 12-week oral study with rats were reduced spermatogenesis, atrophy of seminiferous tubules, reduced litter size, and ultimately infertility as well as increases in hemo- siderin deposition in the spleen. Although DNB is a potent testicular toxicant, no information on potential reproductive toxicity in females is available, and no multi-generation reproductive or developmental toxicity studies were located. No lifetime or carcinogenicity studies were found. DNB is mutagenic in some Salmonella strains. OTHER CRITERIA, ANALYSES, AND TREAT- MENT TECHNOLOGIES The American Conference of Governmental Industrial Hygienists (ACGIH) 8-hour time- weighted average Threshold Limit Value for ex- posure to DNB and the Occupational Safety and Health Administration (OSHA) standard for expo- sure to all dinitrobenzenes are 1 mg/m3. Methods available for the analysis of DNB in- clude gas chromatography, electron capture, tan- dem mass spectrometry, and spectrophotometric determination. Treatment technologies for the removal of DNB in wastewater include aerobic or anaerobic microbial degradation, photolysis, and slaking with lime. ------- Physical and Chemical Properties Empirical Formula c6h4n2o4 Synonyms DNB, 1,3-DNB, m-Dinitrobenzene, m-DNB CAS Number 99-65-0 NQ« Physical State Colorless to yellow crystalline solid at room I ^ temperature Molecular Weight 168.11 || Boiling Point 300-302°C at 770 mm Hg L II Melting Point 89.8°C Specific Gravity 1.571 at 0-4°C Vapor Pressure 0.0039 mm Hg at 20°C Solubility In water: 369 mg/L at 20°C and 500 mg/L at 25°C. Health Effects Data and Advisory Values Genotoidty Mixed results (positive and negative) in Salmonella typhimurium strains with and without activation. No effect on Saccharomyces cerevisiae or Escherichia coli. No increase in unscheduled DNA synthesis in cultivated rat hepatocytes. Reproductive and Developmental Effects Nine studies of male reproductive function using single, short-term, or longer- term oral doses show testicular damage and infertility. However, no repro- ductive or developmental studies evaluating potential reproductive effects in females are available. Cancer Classification EPA Group D, not classifiable as to human carcinogenicity. Reference Dose (RfD) 0.0001 mg/kg/day Drinking Water Equivalent Level (DWEL) 0.005 mg/L Health Advisory Values One-Day Ten-Day Longer-Term (child) Longer-Term (adult) Lifetime 0.04 mg/L 0.04 mg/L 0.04 mg/L 0.14 mg/L 0.001 mg/L This summary was developed using information from the Drinking Water Health Advisory. For further information contact EPA's Office of Science and Technology at (202) 260-7571. Office of Science and Technology Office of Water U.S. Environmental Protection Agency 401 M Street, SW Washington, DC 20460 June 17,1991 ------- |