Exposure of workers to volatile organic compounds during explosives manufacturing

Abstract

This study was conducted at a manufacturer of heavy calibre ammunition as well as electro-detonators for the mines and different defence forces. Thirteen most exposed subjects were chosen (according to the Occupational Exposure Sampling Strategy Manual (OESSM)) in four different departments where these subjects were exposed to volatile organic compounds (VOC's) in the normal line of duty. VOC's are organic (carbon containing compounds) chemicals that have a high vapour pressure and easily form vapour at normal temperature and pressure. VOC's include solvents such as benzene, alcohols, ethanol, toluene, acetone and more of these solvents can be used as paint additives. As can be seen in the literature review VOC's can cause adverse effects if the worker is exposed to levels above the occupational exposure limits and the control measures are not in place. Because of the severity of exposure to VOC's and the relation between occupational hygiene and occupational health (biological monitoring), the study was conducted to determine worker exposure. Estimating occupational exposure is difficult. This is due to a variety of factors, which include the following: worker exposures vary within the same job position, exposures vary during one workday, multiple routes of absorption, personal protective equipment (PPE) may be used inconsistently, and solvents are commonly used as mixtures. For environmental exposure, similar challenges exist. Thus it is important to take biological monitoring into consideration as a way of determining exposure. During the study three entities were considered to determine exposure. Firstly activated charcoal tubes were used to determine personal exposure. Secondly, the amount of VOC's that was in the worker's body was determined via biological monitoring. Lastly, control measures were considered and the air flow was measured to determine whether the controls were effective (extractor systems and protective equipment). After the evaluation process the results indicated that although there was exposure to solvents, the workers' health was not at risk. I t can thus be seen that if the workers are exposed to VOC's and the control measures are in place it will not lead to the adverse health effects that can be caused by exposure to VOC's. During the study there were a few subjects that were exposed to VOC concentrations above the action levels and the effect of this could also be seen in the biological monitoring results. Where defects were noticed, different control measures according to the hierarchy of control, further biological monitoring was suggested.