Exposure to them should be avoided by these groups of workers. Over the past decade there has been concern about the possibility of genetic and physiological effects resulting from long term exposure to some inhalation anaesthetics. Where properly maintained gas scavenging systems are in use there is usually no difficulty in keeping concentrations below these levels. They achieve this by interfering with the essential functions of the cell, especially those involving cell division and can, in the long term cause damage to the sperm and egg cells. Some can cause cancer.
Occupational exposure is usually by inhalation or absorption through the skin.
These substances are exempt from the normal labelling requirements because they are drugs. Those who are trying to conceive a child, are pregnant or breastfeeding, should avoid exposure to such materials. Carbon monoxide readily crosses the placenta and may result in adverse effects on the foetus. High levels may be found in vehicle repair workshops or other areas where internal combustion engines are run without adequate extract ventilation. There is no indication that breastfed babies suffer adverse effects as a result of their mother's exposure to carbon monoxide.