An assessment of fertility in boron-exposed Turkish subpopulations: 2. Evidence that boron has no effect on human reproduction.

In order to assess the effects of boron and its compounds on human health in a country with the world's largest deposits, investigations were carried out on fertility and reproduction in the most highly exposed populations. The 927 probands, 697 male and 230 female, interviewed in the field were selected from six different areas of Turkey, in the provinces of Balikesir, Eskisehir, and Kutahya, with the highest boron deposits. These people are exposed to boron environmentally or occupationally or both. The drinking waters of high-boron soils contain 0.7-29 mg B/L compared with 0.05-0.45 mg B/L of low-boron soils. By the so-called pedigree technique 5,934 marriages were ascertained over three generations from all study areas. Childless families among 911 probands were 29 in number and 3.17% in frequency with minor variations from one area to the next, and 3.0% averaged over the generations. Infertility rates in a boron-free community near Ankara with 625 families studied over three generations was 4.48%, and in a larger population of 49,856 families randomly investigated by us throughout the country was 3.84%. No significant differences were observed in terms of marital status and childbearing between 222 and 399 occupationally boron-unrelated and boron-related men, respectively. Nor was there any difference with respect to other aspects studied. It was concluded that, within the limitations of this study, there was no evidence that boron interferes with human fertility and reproduction.