Page 1 - Combined_9_OCR

---------- 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.)
tract.
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.,