An increased incidence of infertility and miscarriage was observed in the mountain village of Teplice in the Czech Republic. The US EPA and the Czech Republic Ministry of Health sponsored a study (Rubes et al. 2005) to determine the impact of valley smog during the winter inversion period compared to the cleaner air in summer. The smog was created by industrial and private burning of soft lignite. 18-year-old army recruits in Teplice were compared to recruits from Prachatic, a mountain town with clean air.
The chart shows that 90% of the young men had elevated %DFI levels. 25% of these young men had values above 30% (DFI). Despite unremarkable values in the semen analysis, the probability of infertility is high! Males aged 18 to 20 typically have a DFI of around 5%.
In a two-year study, the % DFI was the only metric that responded to seasonal variation in smog levels—classic seed analysis values did not vary in response to smog levels.
In the mountain valley village of Teplice, Czech Republic, there was a high rate of infertility and miscarriages. The US EPA and Czech Republic Health Ministry sponsored a study (Rubes et al 2005) to determine the effects of valley smog during the winter inversion times as compared to the summer time cleaner air. The smog was produced by industrial and home burning of soft brown coal. 18-year-old army recruits in Teplice were compared to the recruits from Prachatic, a clean air mountain town.
The chart above shows that 90% of the young men had elevated %DFI values. 25% of these young men had values at the level (30%DFI) of being a risk for infertility – in spite of the fact of a normal semen evaluation! 18-20 yr old men normally have an approximate 5% DFI.In a two year longitudinal study, the only semen sample measure that responded to the seasonal variation level of smog was the SCSA derived % DFI – the routine semen measures did not vary in response to the level of smog.