Assessment of the working-environment harmful factors and health risk of workers in a nitrogen fertilizer plant.

The authors examined the influence of harmful factors of the working environment such as: microclimate, dust, noise, vibrations, and chemical noxes such as: ammonia, nitric oxides, hydrogen fluoride and gaseous fluorides, on the health status of workers involved in the production of fertilizers and ammonia in a nitrogen fertilizer plant. Various biochemical examinations of 158 workers were carried out. The morbidity rate for 1993-1995 was also studied. The biochemical monitoring indicated a statistically significant dependence of the abnormalities of the biochemical parameters on the professional exposure. The metabolic disturbances were proved by serum creatinine and urea elevations and rising urinary ammonia concentrations, by disturbances of the liver function consisting in an enhanced transaminase activity, and by disorders of the mineral metabolism presented with an increased urinary phosphorus excretion at a low serum phosphorus level as well as with increased serum and urinary fluorine concentrations. The temporarily registered morbidity rate showed a tendency towards an increase in diseases of the respiratory, gastrointestinal and cardiovascular system.

[Kinetics of fluorine elimination in exposed workers]. / Kinetika na eliminirane na fluor pri eksponirani rabotnitsi.

The fourteen-day kinetics of fluorine (F) elimination in urine was followed up in 24 operators from three main workshops of the plant for phosphorous fertilizers. The concentration of F in urine was determined at the beginning, by 6th h and during the last two hours of a working shift in four successive days and at the beginning of the following production cycle after the discontinuation of the exposure. In parallel, the gas-like fluorine compounds in the air of working environment was also determined. Analogous investigations were performed with a control group--30 non-exposed workers. A potentio-metric method with fluorine-selective electrode was used for the determination of F content in urine and the concentration of the gas-like fluorides in the air. A well manifested tendency to increased excretion was established by the end of the working shift and in the course of the working cycle. The data on the rate of fluorine elimination show that it is the highest during the last two exposure hours, most manifested in the workers from the workshop TSP, less-in the workshop PhA and least--in the workshop NTPP. The concentration of fluorine ions in urine for the three groups of workers investigated, was increased as compared with control values, both by 6th h and during the last two hours.