Document Q5w7QLOL7b2M4EGOk96bz8x6

ABSTRACTS FROM CURRENT LITERATURE 433 Fluorides in Air of a Water Plant Feeding Sodium Fluoride. Jerome C. Zufelt, Water & Sewage Works 97:335-336, 1950. When atmospheric samples were examined at various locations in a HsO plant where NaF is fed as a municipal anticaries measure, the F concentration varied from 0.025 to 0.134 rrig:/cu. m. for routine operations, compared with the maximum allowable concentration of 2.5 mg./cu. m. Dumping barrels into a hopper produced an atmospheric concentration of 8.89 mg./cu. m. Urinary F concentrations determined for plant personnnel varied from 0.1 to 1.58 mg./l. of urine, with an average of 0.72, as compared to the concentration of 2 mg./l. considered as indicative of excessive F absorption. c L Campbell [Chem. Abst.]. Determination of Free Quartz in Lorraine Iron Ores. J. Aubry and G. Turpin, Rev. met. 47:146, 1950. A 1 Gm. sample ground to pass 120 mesh is treated in the cold with AcOH-AcONa of pH 2.5, filtered through a tared ALOs crucible, and the precipitate boiled for a few minutes in 20 per cent Na2S solution. After filtering through the same crucible the precipitate is transferred into the original beaker, boiled with 100 cc. of NaaS solution, filtered through the crucible, and washed with hot H20. The precipitate is transferred to a beaker, treated with 200 cc. HC1 and 200 cc. HNO3 and then filtered through the crucible, washed with hot H20, dried, and weighed' J. D. Gat [Chem. Abst.]. Atmospheric Contamination by Petroleum-Treating Establishments. B. P. Gurinov and F. I. Dubrovskaya, Gigiena i Sanit., 1948, no. 12, p. 20. In the atmosphere surrounding the areas of petroleum refineries handling high-S raw material, H2S is found in significant amounts in a 3 km. radius (over 0.5 mg./cu. m.), Typical atmospheric analyses in cities in the vicinity of the refineries are cited, indicating the necessity for rigid control of waste gases in such installations. Especially in foggy weather the H2S concentration may be significant under proper wind conditions in locations 1 or more kilometers away from the plant. G. M. Kosolapoff [Chem. Abst,]. Sanitary and Hygienic Working Conditions in Use of Shale Generator Tar for Binder in the Casting Industry. E. M. Stepanenko, Gigena i Sanit. 1950, no. 5, p. 24. Thermal decomposition of shale generator tar forms harmful gaseous products which contain appreciable amounts of CO. Vegetable oils used as binding agents give a similar gaseous decomposition and actually generate more gases than the tar. The volatiles from the tar include aldehydes and phenols, as well as appreciable amounts of S02 and volatile S compounds; The results of air analysis in various locations in a casting plant are given. G. M. Kosolapoff [Chem. Abst.]. Prophylaxis of Manganese Poisoning in Steel Smelting. S. V. Miller, V. N. Dymchenko, S. D. Likhtenshtein and M. 1. Episheva, Gigiena i Sanit. 1950, no. 1, p. 26. Air analysis in various locations of a steel-treating plant showed numerous locations contain ing over 0.0003 mg./l. of Mnthis is especially true in winter months. Usually MnO and Mn304 are found in the aerosols. Localized, individual suction outlets are recommended, especially at the sites of melting operations for generally improved ventilation. G. M. K. [Chem. Abst.]. Some Problems of Industrial Air Analysis. Velimir Vouk and Mirka Fugas, Arhiv za~ Higijenu Rada 1:168-191, 1950. v Some important problems of industrial air analysis are discussed: (1) maximal allowable concentrations, (2) sampling procedures and (3) calibration of instruments and analytical methods. Tables comparing American, British,, and Soviet maximum allowable concentrations are included. English Summary.