The recent report on benzene exposure among Thai gas station attendants is very interesting. However, this work is a simple study on an out of date biomarker with some problems to be considered. There is a previous report from the same setting among the same population. The present redundant work, without citation of the previous study, 2 has many interesting findings. First, the average level of the t, t-MA measured in the present report is significantly different from that of the previous report. This might reflect either the significant changes in the study pollution in this area or a problem in the laboratory analysis of the samples.