| Airborne levels of bacteria, fungi, and endotoxins were quantified in the live chicken hanging areas of two poultry processing plants in North Carolina. Workers at both plants hang approximately 8,300 birds per h on a moving conveyor located in an enclosed area; those at plant A with negligible exhaust ventilation and those at plant B with an air scrubbing exhaust system. Sampling at 1.0 CFM with a six stage Andersen microbial impactor, plant A showed mean CFU in excess of 5.6 x 10('5)/m('3) for total respirable bacteria and 1.9 x 10('5)/m('3) for bacteria 4.7 (mu)m and below. Plant B had values in excess of 5.0 x 10('5)/m('3) and 1.2 x 10('5)/m('3), respectively. Organisms were primarily gram-positive, predominantly Micrococcus, Staphylococcus, and Corynebacterium. Total respirable coliforms were 9.1 x 10('3)/m('3) for plant A, and 4.9 x 10('2)/m('3) for plant B, while mean values for all gram-negative organisms were 1.4 x 10('4)/m('3) for plant A, and 7.7 x 10('3)/m('3) for plant B. Of all gram-negative organisms isolated and identified, Escherichia, Citrobacter, Acinetobacter, Pseudomonas, and Alcaligenes were dominant. Antibiotic susceptibility testing of 289 gram-negative organisms yielded high resistance to tetracycline (82.7%), streptomycin (72.7%), furazolidone (58.5%), and sulfathiazole (26.6%). Sampling at 12.5 L/min with the all-glass impinger, mean levels of free respirable endotoxin were 130 ng/m('3) for plant A and 70 ng/m('3) for plant B. Levels of fungi were 5.1 x 10('4)/m('3) for plant A and 1.3 x 10('4)/m('3) for plant B. Molds were primarily Cladosporium, Penicillium, Aspergillus, Alternaria, and Scopulariopsis. Predominant yeast groups were Cryptococcus/Rhodotorula, Torulopsis/Saccharomyces, and Candida. Assuming a 20 L/min breathing rate, the total inhaled microbial particle burden would be 6.0 x 10('6) per 8 h for plant A, and 5.0 x 10('6) per 8 h for plant B. Inhaled levels of free endotoxin would be 1.25 (mu)g per 8 h for A and 0.67 (mu)g per 8 h for B. Particle sizing indicates aerosolized organisms may reach every part of the lung. Worker exposure to airborn bacteria, yeasts, molds, endotoxins, and other pollutants indicates the potential for respiratory disease. The at-risk population of poultry workers exposed daily to high concentrations of biological aerosols throughout the industry exceeds 40,000. Other poultry processing plants should be inspected, and epidemiologic studies are indicated. Specifically, control measures should include adequate exhaust ventilation for plant A and a redesign of the existing system for plant B. Personal respiratory protection programs are recommended throughout the industry. |
