Leather Production Data

Exposure Levels in Environmental Media. Limited data suggest that NDMA may be found in urban air, but recent comprehensive monitoring data pertaining to the detection of NDMA in ambient air are needed to establish this fact. Occurrence of NDMA in air has been associated with rubber products, leather products, and cigarette smoke and measurable levels of NDMA have been found in car interiors. This information, combined with the fact that NDMA has been found in ambient air at various urban locations, suggests that detectable levels of NDMA exist in the interior air of homes, offices, etc. Studies pertaining to the monitoring of NDMA in indoor air are needed to confirm this supposition. 

Data on leather belting, mechanical leather packings, and textile leathers production and labor , quarterly sales and prices , monthly. 

Leather Produd.ion Data, Tanners Council of America, 100 Gold St.. New York monthly, vWth annual summary, 1922-. Production of leather and leather products. 

Tanneries use around 2-3 kg of chemicals for every kilogram of leather that is produced. It is not uncommon that a medium-sized tannery uses around 30CM-00 different chemicals in the production, and recent published data from a tannery showed they were using around 350 different chemicals in the production [1]. It should also be noted that less than 20% of the weight of the hides that will be processed will actually end up as leather. The remaining part will become waste or by-products. A typical mass balance from a tannery producing leather from bovine hides is given in Fig. 1. 

Information on leather belting, mechanical leather packings, and textile leathers is assembled by the American Leather Belting Association, of New York. Monthly production and price data on these commodities are assembled for members, as well as quarterly labor and production information. 

A great deal of work has been carried out on the TLC separation of various classes of synthetic dyes on untreated plates. Dyes from various sources, namely, foodstuffs (fruits, oils spices, alcoholic products), coated tablets, leather, fibers, cosmetics, etc., are first extracted and then applied to the layers. About 200 ml of developing solvent in a chromatographic development tank is then used to develop the chromatograms up to 10 cm. The data for the di fferent developing solvents and adsorbents (stationary phases) used for the separation of a variety of synthetic dyes, along with specific characteristics of the separation procedure, if any, are tabulated in Table 1. Details of specific separations follow. 

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