The Effect of Low-Level Indoor Exposure Toluene on Orienting Network

Objective. The aim is to explore the effect and mechanism of indoor toluene exposure on orienting network. Methods. Twenty-two healthy adults were exposed to 0 ppb, 17.5 ppb, 35 ppb, and 70 ppb toluene for 4 hours, respectively. All subjects underwent attention network behavioral test, and their electroencephalographic activity was recorded simultaneously. The causal connection strengths of orienting network were calculated through direct transform function (DTF) methods. The DTF values of orienting networks among four groups were compared. Results. (1) The DTF values of parietal outflow (DTF_outflow) in 70 ppb toluene condition were higher than those of the 0 ppb, 17.5 ppb, and 35 ppb conditions, respectively. (2) The DTFCZ- FZ and DTFCZ- FP2 values of 70 ppb toluene condition were found to be lower as compared to 0 ppb condition. The DTFCZ- FP2 values of 70 ppb condition were lower as compared to those of the 17.5 ppb condition. Furthermore, DTFP3-FP2, DTFP4-FP1, and DTFP4- FZ values of 70 ppb condition were higher as compared to those of the 0 ppb condition. The DTFP3- FP2 values of 70 ppb condition were higher as compared to those of the 17.5 ppb condition. The DTFP4- FP1 values of the 70 ppb condition were higher as compared to those of the 17.5 and 35 ppb conditions. Conclusion. Even short-term exposure to indoor toluene at low concentrations significantly impacts orienting network.