When game birds consume contaminated seeds, methylmercury can accumulate in tissue at levels higher than those accepted as safe for human consumption. All forms of mercury can be converted to methylmercury and are potentially hazardous Unacceptable levels of mercury vapor were recorded not only in incubators but in the room atmosphere of special care baby units during a 1985 survey of health regions in England. The breakage of clinical glass thermometers and spill of mercury were responsible for this air contamination and significant risk of poisoning. The scale of the problem and potential risk could be appreciated by a report of 1600 broken thermometers over a 6-month period at a Glasgow Children's Hospital. Broken barometers in the home and sphygmomanometers in doctor's offices are additional sources of mercury vapor poisoning.
Spilled mercury gravitates to cracks in the floor and into the pile of carpets.
Vacuuming a contaminated area may facilitate the spread of mercury vapor throughout the house, and warm air from heating ducts and vents may enhance volatilization. Since mercury concentration is likely to be highest near the floor, toddlers may be at greater risk of poisoning than adults. The child becomes listless, restless, and irritable. The tips of the fingers, toes, and nose acquire a pinkish color, a distinctive feature of the disease, and generalized transient skin rashes are a frequent occurrence. The hands and feet are swollen and the skin of the palms and soles sheds in scales or sheets.