Diseases from poisonous gases and micro-organisms in the air near garbage dumps and poisoning by polluted underground water and soil may result in serious health problems. The object of this study was to determine the negative impact of their occupation on full-time garbage collectors and to determine the microbiologic flora of their immediate environment. This study was performed with 228 selected individuals who worked daily in 5 different garbage collection units in several districts of Istanbul. The level of exposure to microbiologic flora was studied using a Merck Air Sampler MAS 100, and total bacteria, yeast and mildew concentrations per square metre and minute (cfu/m(2)/min) were calculated. Respiratory functions of all individuals in the study were evaluated with a computerised spirometer (MIR spirobank). Aspergillus and Penicillium spp. were the commonest species detected followed by Candida spp., Mycelia sterilia, Rhizopus spp. and Mucor spp. The study of respiratory functions showed that the FVC%, FEV1%, PEF% and FEF25-75% of the garbage collectors were below 80% compared to non-collectors: OR = 2.89 (95% Cl 1.14-7.30) in FVC%, OR = 2.89 (95% CI 1.41-5.92) in PEF%, OR = 2.46 (95% Cl 1.33-4.56) in FEF25-75% and OR = 4.48 (95% CI 1.90-10.58) in FEV1%. A long expirium period and ronchus symptoms were detected in 11 collectors (31.4%) and 4 drivers (11.4%) out of 32 collectors and 35 drivers whose respiratory function tests gave low values. Clinical findings between the two groups were statistically significant (p < 0.05), OR = 4.06 (95% CI 1.13-14.46). The exposure to airborne microbes could produce respiratory disorders, gastroenteritis, dermatitis and many other complaints.