Risk assessment of chemicals in a toxicological laboratory: A case study

The toxicity of a chemical substance in a workplace depends on both its physical and
chemical properties, the level of concentration in the breathing air, as well as, the duration of
the exposure. In order to ensure healthy conditions at workplace, international organizations,
such as the World Health Organization (WHO) and the International Labor Organization (ILO),
have instituted upper limits of concentration for several chemicals that could provoke serious
problems or disturbances on human health.
The aim of the present paper is the estimation of the concentrations of ethanol, ethyl acetate
and chloroform, which are widespread solvents used during routine analyses in a toxicological
laboratory.
The monitoring of the solvents at the laboratory was carried out during the summer period of
two successive years. The monitoring was focused on the estimation of: a) the meteorological
parameters (temperature and air humidity), b) both inhalation and dermal exposure
concentrations by using personal air sampling systems, c) the concentrations in the
environmental air of the laboratory and d) the concentration in urine samples of the
employees. The above-mentioned activities have been achieved through the use of
appropriate air samplers which employees were carrying both on the height of inhalation zone
and their arms. For the qualitative and quantitative estimation of the concentrations, chemical
substances were extracted with the use of carbon sulphide and then by the use of gas
chromatographic technique equipped with flame ionization detector. Urine analyses were
done by colorimetric techniques.
The results of the monitoring showed concentrations of ethanol, ethyl acetate and chloroform
over those instituted for workplaces. In this paper, results of the monitoring are discussed and
proposals for ensuring air quality at workplace are suggested.