Q: I work in a high volume clinical lab, where there are a lot of fumes of xylene and I am 4 weeks pregnant. My manager tells me that I shouldn't worry but I am very concerned. Please advise.

A:Xylene (dimethylbenzene or xylol) is an aromatic hydrocarbon solvent commonly found in paints and laboratories. It enters the body rapidly on inhaling and can also be absorbed through the skin, particularly if the period of contact is lengthy. Overexposure to xylene most commonly affects the nervous system, respiratory system and skin. Depending on the levels, it may lead to nausea, headache, feeling high, dizziness, weakness, irritability, vomiting, slowed reaction time, giddiness, confusion, clumsiness, slurred speech, loss of balance, ringing in the ears and, at levels in excess of 10,000 ppm, may lead to sleepiness, loss of consciousness and even death. The fumes can irritate eyes, nose, and throat while frequent or prolonged skin contact can cause dermatitis with dryness, flaking, and cracking of the skin. When xylene levels are >200 ppm, it irritates the lungs causing chest pain and shortness of breath. Extreme overexposure can result in pulmonary oedema. Studies in pregnant animals have been inconclusive as exposure to very large amounts of xylene (not normally encountered) affected the developing fetuses. Extreme levels of xylene that killed some of the pregnant animals caused birth defects in the offspring of the survivors. However, it is still not clear if xylene can affect pregnancy or reproductive function in humans. Commonsense demands that pregnant and nursing women minimise their exposure to xylene, just as they should minimise their exposure to alcohol, tobacco, and other drugs.