Page 1 - Combined_9_OCR
P. 1

----------    ajuv. LAmuE, <uGri5C.ilCiMBr (Bromobenzylnitrile)                        4» Physiological Response
                                                                                                                                 Since the introduction of this material in
                                     1.  Physical and Chemical Properties
                                                                                                                             there have been a number of reports of. sever
                                         Molecular weight: 182.03                                                            beginning after a latent period with repeated
                                         Melting point: 25°C.                                                                acute asthmalike reaction/6 Direct pulmona
                                         Boiling point: 225°C.                                                               mals,77 although the specific picture of a sen
                                         Density: 1.47 (solid)                                                               reproduced in animals. Skin sensitization in a
                                         Vapor density: 6.6 (air = 1)                                                        does not appear to have been a major problem
                                         Vapor pressure: 0.01 mm. Hg (20°C.)                                                     Merewether78 points out that the isocyans
                                                                                                                             are known to react with various groupings in
                                     2.  Physiological Response
                                                                                                                             of forming antigens. The reaction is probably
                                         Bromobenzylcyanide is a highly potent lachrymator. The CN group is prob­            of phenyl isocyanate, the reaction leads to t
                                     ably released and converted to SCN.4 Like some other potent lachrymators, it            acid.79 There seems little doubt that the pu
                                     probably acts by a progressive reaction with SH groups.75                               based on some type of delayed or sensitization-
                                         Prentiss25 gives the physiological effects of various levels in air as follows:         Because the pulmonary effects can be pr<
                                         Lowest detectable level: 0.09 mg./cu. meter                                         air, TDI should only be used in areas with ad
                                         Lowest irritant concentration: 0.15 mg./cu. meter                                   or with air-supplied respirator equipment. SI
                                         Intolerable concentration: 0.8 mg./cu. meter (10 min.)                              sons with chronic respiratory disease or respire
                                         Lethal concentration: 900.0 mg./cu. meter (30 min.); 3500.0 mg./cu. meter               Other isocyanates may have irritant pr
                                     (10 min.)
                                                                                                                             5,  Threshold Limit Value
                                     TOLUENE-2,4-DIISOCYANATE, CH3C6H3(NCO)2 (Tolylene
                                     2,4-diisocyanate, TDI)                                                                      0.02 p.p.m. (0.14 mg./cu. meter).24 May n
                                                                                                                             specific sensitization.
                                     1.  Uses and Industrial Exposures
                                                                                                                             6.  Odor Threshold
                                        TDI is used in manufacture of polyurethane foams, foam-type insulation, etc.
                                                                                                                                 0.4 p.p.m. in about half of subjects.
                                    2.  Physical and Chemical Properties
                                                                                                                             SODIUM DICYANAMIDE, NaN(CN) 2
                                        Physical state: white liquid
                                        Molecular weight: 174                                                                1.  Uses and Industrial Exposures
                                        Boiling point: 250°C.
                                                                                                                                 Sodium dicyanamide is used as a chemi'
                                        Specific gravity: 1.21 (28°C.)
                                                                                                                             moths and to have some insecticidal properties
                                        Vapor density: 6.0 (air — 1)
                                        Vapor pressure: 1 mm. Hg (80°C.)                                                     2.  Physical and Chemical Properties
                                        Insoluble in water; soluble in acetone, ethyl acetate, toluene, and kerosene             Physical state: colorless crystals
                                        1 p.p.m. O 7.12 mg./cu. meter and 1 mg./liter o 140.5 p.p.m.                             Molecular weight: 89.04
                                                                                                                                 Melting point: 315°C. (decomposes)
                                    3.  Determination in the Atmosphere
                                                                                                                                 Soluble in water: 26.5 g. per 100 g. of >
                                        Colorimetric methods are available.76                                                4.2 g. per 100 g. of methanol at 30°C.
                                        T' M. Dixon, Biochemical Society Symposia No. 2, Cambridge Univ. Press, Mass., 1948.     77  J. A. Zapp, Jr., Arch. Ind. Health, 15, 324 (19&
                                        78 American Ind. Hyg. Assoc. Hygienic Guide, Toluene 2,4-Diisocyanate, Am. Ind. Hyq.     78  E. R. A. Merewether, Industrial Medicine ante
                                    Assoc. Quart., 18, 370 (1957).                                                            1956.
                                                                                                                                 78 J. S. Fruton, General Biochemistry, 2nd ed.,
   1   2