Thermal-breakdown products

Potential toxicity of the agent, its thermal breakdown products, or products generated on contact with chemicals will determine safety measures necessary (e.g. in occupied areas a double-knock system, allowing evacuation time, may be required. 

The process produces some organic waste derived from the thermal breakdown products of the wood, which is dealt with in a biological treatment facility. Volatile by-products are removed in a scrubber associated with a steam-condensing unit. Energy consumption is 2.8MJ to produce 1 kg of modified wood and the cost of production is about 150 Euros per m, with operational costs of 20 Euros per m. A plant capable of an annual production capacity of 75 000 m would require an initial investment of some 10-15 million Euros. 

A possible explanation of the results obtained with our procedure is that the water in the water-saturated SE-52 solution may be required for hydrolysis of the silicone polymer, and the breakdown products so produced, effectively silanize the Chromosorb G at 370°. It is also possible that a similar process may account for the silicone polymer treatment of the oxidized steel column. Here again, a thermal breakdown product of SE-52 may react with the metal oxide on the inner surface of the metal column to produce a layer which is less polar than the oxide itself. This might then lead to less adsorption and/or less destruction of the compounds being analyzed. Such a reaction might also account for the improvement in peak shape when stainless steel columns are heated in air prior to packing. The oxide or partial oxide so formed may facilitate subsequent reaction with the thermal decomposition product of the silicone polymer. It is important to note, however, that this thermal breakdown product must be formed in the absence of free oxygen. 

D. Thermal-breakdown products. Under fire conditions, many organic substances will break down to other toxic substances. The amounts, kinds, and distribution of breakdown products vary with the fire conditions and are not easily modeled. Information on the likely thermal-decomposition products is included because of their importance in the assessment of health hazards underfire conditions. 

The thermal-breakdown product information found in Table IV-4 is derived primarily from data found in the literature and the general oonsiderations described immediately above. Aside from the NFPA oodes, Table IV-4 does not cover the chemical reactivity or compatibility of substances. 

TLV, is an adequate warning property. Vapor pressure is 73 mm Hg at 20°C (68°F). Flammable. Thermal-breakdown products include oxides of nitrogen and cyanide. May be found in products for removing sculptured nails. 

Allyl propyl disulfide (onion oil [CAS 2179-59-1]) Mucous membrane irritant and lacrimator. 2 ppm Liquid with a pungent, irritating odor. A synthetic flavorant and food additive. Thermal-breakdown products include sulfur oxide fumes. 

Bromoform (tribromomethane [CAS 75-25-2]) Vapors highly irritating to eyes and respiratory tract. Well absorbed by inhalation and skin contact. CNS depressant. Liver and kidney injuiy may occur. Two preliminary tests Indicate that it may be an animal carcinogen. 0.5 ppm, S,A3 850 ppm Colorless to yellow liquid. Chloroform-like odor and Irritahon are adequate warning properhes. Vapor pressure is 5 mm Hg at 20°C (68°l. Not combustible. Thermal-breakdown products Include hydrogen bromide and bromine. 

Caprolactam (CAS 105-60-2) Highly Irritating to eyes and skin upon direct contact. Vapors, dusts, and fumes highly irritating to eyes and respiratory tract. Convulsant activity in test animals. 1 mg/m (dust) 5 ppm (vapor) [proposed 5 mg/m (aerosol and vapor)] White solid crystals. Unpleasant odor. Vapor pressure is 6 mm Hg at 120°C (248°F). Thermal-breakdown products include oxides ot nitrogen. 

Chlordane (CAS 57-74-9) Irritating to skin. A CNS convulsant. Skin absorption is rapid and has caused convulsions and death. Hepato-toxic. Evidence of carcinogenicity in test animals (lARC 2B). See also p161. 0.5 mg/m. S,A3 100 mg/m Viscous amber liquid. Formulations vary in appearance. A chlorine-llke odor. Vapor pressure Is 0.00001 mm Hg at20°C (68°F). Not combustible. Thermal-breakdown products include hydrogen chloride, phosgehe, ahd chloride gas. EPA bahhed this insecticide in 1976. 

Chlorodilluoromelhane (Fieon 22 [CAS 75-45-6]) Irritatihg upon direct contact. Vapors mildly irritating to eyes and respiratory tract. A CNS depressant. High-level exposure may cause arrhythmias. There is evidence at high doses for adverse effects oh fetal developmeht in test animals. See also p 209. 1000 ppm Colorless, almost odorless gas. Nonflammable. Thermal-breakdown products may include hydrogen fluoride. 

Colorless, odorless gas. Thermal-breakdown products include hydrogen fluoride and hydrogen chloride. 

Demeton (Systox, mercaptophos [CAS 8065-48-3]) An organo- phosphate-type cholinesterase inhibitor (see p 291). 0.05 mg/m , S 10mg/m A sulfur-like odor. A very low vapor pressure at 20°C (68°F). Thermal-breakdown products include oxides of sulfur. 

Dibromo-3-chioropropane (DBCP [CAS 96-12-8]) Irritant oi eyes and respiratory tract. Has caused sterility (aspermia, oligospermia) in overexposed men. Well absorbed by skin contact and inhalation. A carcinogen in test animals (lARC 2B). OSHACA NIOSH CA Brown liquid with a pungent odor. Combustible. Thermal-breakdown products include hydrogen bromide and hydrogen chloride. No longer used as a pesticide in the US. 

White solid with a chlorine-llke odor. Odor and eye irritation occur below the TLV and are adequate warning properties. Not combustible. Thermal-breakdown products include hydrogen chloride, phosgene, oxides at nitrogen, and chlorine gas. 

Dichloropropene (1,3-dichloropropylene, Telone [CAS 542-75-6]) Based on animal studies, irritating upon direct contact. Well absorbed dermally. Vapors irritating to eyes and respiratory tract. In test animals, moderate doses caused severe injuries to the liver, pah-creas, ahd kidheys. A carcinogen in test animals (lARC 2B), 1 ppm, S 2 3 0 Colorless or straw-colored liquid. Sharp, chloro-form-like odor. Polymerizes readily. Vapor pressure is 28 mm Hg at 25°C (77°F). Thermal-breakdown products include hydrogen chloride and phosgene. 

Dichlarotetralluoroethane (fluorocarbon 114, Freon 114 [CAS 76- 14-2]) Vapors may sensitize the myocardium to arrhythmogenic et-fects of epinephrine at modestly high air ieveis (25,000 ppm). Other effects at higher levels (100,000-200,000 ppm) include respiratory irritation and CNS depression. See also p 209. 1000 ppm 15,000 ppm Colorless gas with a mild ether-like odor. Thermal breakdown products include hydrogen chloride, hydrogen tiuoride, and phosgene. 

Diethylenetrlamlne (DETA [CAS 111-49-0]) Corrosive highly irritat-ihg upoh direct cohtact severe bums may result. Vapors highly irri-tatihg to eyes and respiratory tract. Dermal and respiratory sensitization can occur. 1 ppm, S 3 1 0 Viscous yellow liquid with an ammonla-like odor. Vapor pressure is 0.37 mm Hg at 20°C (68°F). Combustible. Thermal-breakdown products Include oxides of nitrogen. 

Difluorodibromomethane (dibromodifluoromethane, Freon 1292 [CAS 75-61-6]) Based on animal tests, vapors irritate the respiratory tract. A CNS depressant. By analogy to other freons, may cause cardiac arrhythmias. In test animals, high-level chronic exposures caused lung, liver, and CNS injury. See also p 209. 100 ppm 2000 ppm Heavy, volatile, colorless liquid vinth an obnoxious, distinctive odor. Vapor pressure is 620 mm Hg at 20 C (68°F). Not combustible. Thermal-breakdown products include hydrogen bromide and hydrogen fluoride. 

ERPG-2 100 ppm mable. Thermal-breakdown products include oxides... 

DInItrobenzene May stain tissues yellow upon direct contact. Vapors are Irritating to respiratory tract. Potent inducer of methemoglobinemia (see p 261). Chronic exposures may result in anemia and liver damage. Injuries testes In test animals. Very well absorbed through the skin. 0.15 ppm, S 50 mg/m 3 1 4 Pale yellow crystals. Explosive detonated by heat or shock. Vapor pressure is much less than 1 mm Hg at 20°C (68°F). Thermal-breakdown products include oxides of nitrogen. 

Disultiram (tetiaethylthiuiam disultide, Antabuse [CAS 97-77-8]) Inhibits aldehyde dehydrogenase, an enzyme Involved In ethanol metabolism. Exposure to disultiram and alcohol will produce flushing, headache, and hypotension. Disultiram may also interact with other industrial solvents that share metabolic pathways with ethanol. Limited evidence for adverse effects on fetal development in test animals. See also p 185, 2mg/m Crystalline solid. Thermal-breakdown products Include oxides of sulfur. 

Endosulfan (CAS 115-29-7) Inhalation and skin absorption are major routes of exposure. Symptoms Include nausea, confusion, excitement, twitching, and convulsions. Animal studies suggest liver and kidney Injury from very high exposures. Limited evidence for adverse effects on male reproduction and fetal development In animal studies. See also p 161. 0.1 mg/m S Chlorinated hydrocarbon insecticide. Tan, waxy solid with a mild sulfur dioxide odor. Thermal-breakdown products include oxides of sulfur and hydrogen chloride. 

Endrin (CAS 72-20-8) Endrin Is the stereoisomer of dieldrin, and Its toxicity Is very similar. Well absorbed through skin. Overexposure may produce headache, dizziness, nausea, confusion, twitching, and convulsions. Adverse effects on fetal development In test animals. See also p 161. 0.1 mg/m , S 2 mg/m Colorless, white, or tan solid. A stereoisomer of dieldrin. A mild chemical odor and negligible vapor pressure of 0.0000002 mm Hg at 20°C (68 F). Not combustible. Thermal-breakdown products include hydrogen chloride. 

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