Medical surveillance of Catania public sector employees who use video display terminals (VDTs) revealed complaints of eye and upper respiratory tract irritation, skin rash, headache, mental fatigue and reduced concentration in some of the workers. These were employed in three recently renovated offices and showed the above symptoms while at work. Investigations were performed to verify whether contaminants that may cause the above symptoms were present in the indoor air. In particular, levels of formaldehyde and CO2 were continuously monitored. CO2 levels were found to be higher in offices open to the general public as compared to other offices (including the three renovated ones). However, CO2 levels were never above 1,000 ppm. Formaldehyde was found in the indoor air of all three renovated offices in approximately equal concentrations, ranging from a minimum of 0,07 - 0,09 ppm to a maximum of 0,3 -0,4 ppm. In addition, a strong pungent odor typical of this substance was present in all three renovated offices but not in the others. Formaldehyde pollution must always be considered and assessed whenever new furnishings that may have required the use of glues that emit formaldehyde are brought into an indoor environment.