Principles of health and safety in agriculture. Dosman JA, Cockcroft DW, eds., Boca Raton, FL: CRC Press, Inc., 1989 Oct; :190-192
A NIOSH cross sectional environmental and medical study of workers in the nontextile cotton industry was conducted from 1976 to 1982, from which the results of a survey of airborne cotton dust concentrations were summarized. The survey sites included 35 cotton gins, 13 cotton compress warehouses, 13 cotton classing offices, 18 cottonseed oil mills, and 13 cotton waste utilization facilities. Airborne cotton dust concentrations were measured with Lumsden-Lynch vertical elutriators operating at flow rates of 7.4 liters per minute. Dust exposures for individual workers were estimated by monitoring their location during the sampling periods, total time spent in each work area, and combining these data with the appropriate vertical elutriator data. Mean cotton dust exposures in the cotton gins, compress warehouses, cotton classing offices, cottonseed oil mills, and cotton waste utilization facilities varied from 101 to 2050, 39 to 831, 81 to 376, 502 to 2040, and 237 to 3970 micrograms per cubic meter (microg/m3), respectively. The overall mean dust concentrations for the five types of facilities were 521, 229, 165, 1010, and 1390microg/m3, respectively. Fifty (54%) of the 92 facilities had mean cotton dust concentrations of 500microg/m3 or less. Of the 42 facilities with mean dust concentrations above 500microg/m3, all but one were in the ginning, cottonseed oil, and waste utilization sectors. Most of the facilities with the higher cotton dust exposures typically processed material of lower quality, had poor equipment maintenance programs, and had no dust suppression equipment. Of the five types of facilities investigated, the cotton classing offices had the best conditions for assessing individual worker exposures. Unlike the other facilities, the measured dust concentrations were fairly consistent in the various work areas and most of the employees remained in one area during a work shift. Problems with sampling cotton dust concentrations in the facilities were discussed.