For pregnant women represent factors of high risk such substances, as lead, mercury, steams of gasoline, phenol, formaldehyde, connection of cadmium, manganese, fluorine, arsenic, pesticides.
It is known, that lead irrespective of, whether it will get to a digestive path in the form of salts or is inhaled with air in a kind lead, can cause infringement of development of a brain in the child and intellectual backwardness.
At mercury influence on an organism of the pregnant woman its newborn has children's cerebral paralyses and a brain.
Therefore contact to these substances during pregnancy should be as much as possible limited.