Many solvents and volatile organic compounds (VOCs) have been used in various industrial workplaces. The effects of such compounds on human health can be severely detrimental leading to unpleasant symptoms, cancer and even death. The most common routes of exposure are by inhalation and skin adsorption. Thus, chemicals that have the potential to become airborne as gases, vapour, fumes or mists are evaluated by occupational hygienists for their risk of inhalation exposure. Traditional IH surveys have focused on sampling for chemicals used in the industrial workplaces; often missing hazardous compounds due to missing information on MSDS’, wrong MSDS’ in use, unannounced changes to product specifications, or thermal degradation or reaction byproducts from high temperature processes. To understand what airborne chemicals are present in a given workplace environment, a broader picture of the workplace air is necessary before the design of any sampling strategies. With the combination of the MSDS information and the processes used in the plant, a more complete picture of chemical exposure can be obtained. This pre-screening approach will prove to be helpful to employers by reducing unnecessary costs by focusing on the problem at the very beginning. This new approach to industrial hygiene monitoring is also in line with the safe worker environment legal responsibilities of Bill C-45.
Traditional industrial hygiene monitoring for VOCs has been carried out by the collection of target organics onto charcoal or other suitable sorbent. Subsequent to this an extraction would be conducted using a solvent such as carbon disulphide. Analysis by gas chromatography with flame ionization detector (GC-FID) would then follow, completing the process. This approach to IH monitoring is effective when a few known chemicals are being targeted at relatively high concentrations. This approach however, has many limitations especially in complex workplace environments where many chemicals exist or the exact chemicals being used are unknown. It also tends to have significant limitations during thermal degradation or reactions, when byproducts are formed from high temperature processes, for chemicals having low threshold limit values and for areas requiring short sampling times. When traditional IH sampling is applicable in a particular workplace, such sampling may require 5 or more different types of sampling media to be used at each location in addition to the number of samples to be taken. This is the case since traditional NIOSH, OSHA, ASTM, etc. methods for individual and multiple organic compounds are based on specific conditions such as sampling media, extraction solvent, instrument or detector used.