Sex ratio at birth associated with petrochemical air pollution in Taiwan

The petrochemical industry is considered to be the main source of industrial air pollution in Taiwan (EPA/ROC 1992). The mechanism by which pollution could affect the sex ratios at birth is not clear. Williams et al. (1992, 1995) suggested a biological model: the metabolism of the rapidly dividing cells of the gonadal and fetal tissues appears to be particularly vulnerable to the influences of pollutants. Nonetheless, sex ratio at birth has been suggested as a crude but routine index of the quality of public health which can provide early warning of cryptic health hazards from environmental pollution. The objective of the present study was to explore the hypothesis that abnormal sex ratio of births would be found in municipalities with residential exposure to petrochemical air pollution. This report is one in a series of studies evaluating the health hazards from petrochemical air pollution.