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The European Working Conditions Survey of 2017 reports an increasing trend of occupational exposure to hazardous substances. This includes a 3% increase in handling or being in skin contact with hazardous chemicals. Academic researchers describe chemical research laboratories as dynamic and high risk indoor spaces in which large amounts of hazardous matter is consumed. Organic solvents are the traditional medium in which organic synthesis is practiced. Estimates show that over 80% of the organic waste in synthetic chemistry is attributed to the use of organic solvents and most synthetic chemistry researchers are exposed to those solvents on a daily basis. Systemic health effects associated with exposures to carbon based solvents are of high concern. The Belgian codex on well-being at work requires the performance of chemical exposure assessments to assess the acceptability of risks associated with occupational exposure to hazardous chemicals. In academic research laboratories, qualitative risk assessments are typically performed to minimize risks. As organic synthesis laboratories handle large amounts of organic solvents, one may question the suitability of qualitative risk analyses in the context of chemical exposure. The European Chemicals Agency suggests a tiered approach to quantitatively predict exposure concentrations for different exposure routes. In this master thesis, an exposure measurement survey is performed to examine if the currently applied qualitative risk assessment approach is suitable to ensure acceptable exposures to organic solvents in an academic research laboratory setting. Both dermal and inhalation exposure routes are considered. Moreover, the applicability of chemical exposure assessment tools suggested by ECHA is evaluated. The predictive quality of the tools is examined by comparing the tool estimates with the measured concentrations. Analysis of volatile organic compounds showed that researchers of the organic synthesis laboratory under study are in particular exposed to 2-methylpentane, ethanol, acetone, ethyl acetate, ethyl ether, methylene chloride and toluene. Highest inhalation and dermal exposure concentrations are measured for acetone. All daily inhalation exposures are acceptable and the individual substance exposure concentrations are in compliance with their associated regulatory occupational exposure limits according to the statistical test described in the NBN EN 689 standard. In relation to dermal exposure, One-way ANOVA shows that the middle finger and thumb of the right hand are significantly higher exposed to ethanol and the middle finger of the left hand is significantly higher exposed to acetone compared to the concentrations measured on the neck, arm and wrist. Inhalation and dermal exposure estimates are derived for acetone, ethyl ether and methylene chloride. Overall, the exposure estimates are less conservative. However, based on the measured concentrations, ART allows for a Bayesian update of the estimates. In addition, 8-hour TWA estimates of ART can consider up to four different exposure scenarios. This way, the tool can take into account the dynamic nature of the academic research environment. As a result, ART is suggested to complement the qualitative risk assessment approach of the organic synthesis laboratory.
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