Abstract

The aim of this study was to determine the peculiarities of femoral bone osteogenesis in human fetuses in the areas with different levels of environmental pollution with fluoride compounds (the city of Irkutsk and the town of Shelekhov). The histological structure of femoral bones was studied in 70 fetuses aged 15-16, 19-20, 22-25 and 27-29 gestational weeks. Morphometric methods were used to evaluate the number of blood vessels per total area of epiphysis, the length of endochondral trabeculae, the thickness of hypertrophic and columnar cartilage zones, diaphysis wall and its trabeculae thickness, the thickness of endochondral trabeculae merging with the diaphysis wall, and of the bone growing on the epiphysis. It was found that in the city of Irkutzk, relatively remote from the pollution source, the processes of osteogenesis and osteoresorption are balanced and are characterized by the prevalence of osteoblastic activity over osteoclastic activity, ensuring the active bone growth. During weeks 15-22, the bones are actively growing in length, while during weeks 22-29 they grow mainly in width. In the town of Shelekhov, located closely to the pollution source, the growth of bones in both length and width, is delayed. The bone growth was active till week 16, however, during weeks 18-29, osteoresorption prevailed over the osteosynthesis, the bone thickness decreased, while the activity of their growth in length remained reduced.