Video display units: An emission source of the contact allergenic flame retardant triphenyl phosphate in the indoor environment

Triphenyl phosphate, an additive flame retardant with documented contact allergenic effects on humans, was identified in a computerized indoor office environment. The source of emission was found to be the computer video display units (VDUs). Eighteen VDUs were examined, and the outer covers were shown to contain triphenyl phosphate in levels up to 10% (w/w). When using this type of PC equipment with a brand-new VDU in a small office room, the air concentration of triphenyl phosphate raised to near 100 ng/ m(3) after 1 day of operation. The measurements were performed in the breathing zone of an imaginary operator sitting in front of the computer. After 1 week of continuous operation, the concentration of triphenyl phosphate was reduced by half. Furthermore, a decrease to approximately 10 ng/m(3) could be observed after 183 days, which corresponds to more than 2 yr of ordinary business hour operation.