Post by Kevin on May 8, 2006 14:57:37 GMT -5
Signs and symptoms of exposure
1. Acute exposure: The signs and symptoms of acute exposure to carbon monoxide may include headache, flushing, nausea, vertigo, weakness, irritability, unconsciousness, and in persons with pre-existing heart disease and atherosclerosis, chest pain and leg pain.
2. Chronic exposure: Repeated bouts of carbon monoxide poisoning may cause persistent signs and symptoms, such as anorexia, headache, lassitude, dizziness, and ataxia.
Effects on Humans: Carbon monoxide is an asphyxiant in humans. Inhalation of carbon monoxide causes tissue hypoxia by preventing the blood from carrying sufficient oxygen. Carbon monoxide combines reversibly with hemoglobin to form carboxyhemoglobin. The reduction in oxygen-carrying capacity of the blood is proportional to the amount of carboxyhemoglobin formed [Gosselin 1984]. All factors that speed respiration and circulation accelerate the rate of carboxyhemoglobin formation; thus exercise, increased temperature, high altitude, and anemia increase the hazard associated with carbon monoxide exposure[Gosselin 1984]. Other conditions that increase risk are hyperthyroidism, obesity, bronchitis, asthma, preexisting heart disease, and alcoholism [NLM 1993]. In tests with human volunteers breathing 50 ppm carbon monoxide (a concentration that produces 27 percent carboxyhemoglobin after an exposure of 2 hours), there was a significant decrease in time to onset of exercise-induced angina[Gosselin 1984]. Carbon monoxide can be transported across the placental barrier, and exposure in utero constitutes a special risk to the fetus. Infants and young children are generally believed to be more susceptible to carbon monoxide than adults. The elderly are also believed to be more susceptible to carbon monoxide poisoning [Gosselin A carboxyhemoglobin level of 0.4 to 0.7 percent is normally present in the blood of adults. In cigarette smokers, the range is 4 to 20 percent, which places smokers at greater risk in exposure situations [Clayton and Clayton 1982; ACGIH 1991]. A capacity to adapt to carbon monoxide exposure has been reported in several human studies. Healthy young men exposed to carbon monoxide at a concentration of 44 ppm for a prolonged period suffered no adverse health effects [ACGIH 1986]. Men exposed to 50 ppm for several days without relief complained of headaches, but exposure to 40 ppm for 60 days was without effect [ACGIH 1986]. Workers in the Holland Tunnel working 8-hour swing shifts of 2 hours in and 2 hours out at an average carbon monoxide exposure concentration of 70 ppm had average carboxyhemoglobin levels of 5 percent, and none had levels above 10 percent [ACGIH 1991].
www.osha.gov/SLTC/healthguidelines/carbonmonoxide/recognition.html
1. Acute exposure: The signs and symptoms of acute exposure to carbon monoxide may include headache, flushing, nausea, vertigo, weakness, irritability, unconsciousness, and in persons with pre-existing heart disease and atherosclerosis, chest pain and leg pain.
2. Chronic exposure: Repeated bouts of carbon monoxide poisoning may cause persistent signs and symptoms, such as anorexia, headache, lassitude, dizziness, and ataxia.
Effects on Humans: Carbon monoxide is an asphyxiant in humans. Inhalation of carbon monoxide causes tissue hypoxia by preventing the blood from carrying sufficient oxygen. Carbon monoxide combines reversibly with hemoglobin to form carboxyhemoglobin. The reduction in oxygen-carrying capacity of the blood is proportional to the amount of carboxyhemoglobin formed [Gosselin 1984]. All factors that speed respiration and circulation accelerate the rate of carboxyhemoglobin formation; thus exercise, increased temperature, high altitude, and anemia increase the hazard associated with carbon monoxide exposure[Gosselin 1984]. Other conditions that increase risk are hyperthyroidism, obesity, bronchitis, asthma, preexisting heart disease, and alcoholism [NLM 1993]. In tests with human volunteers breathing 50 ppm carbon monoxide (a concentration that produces 27 percent carboxyhemoglobin after an exposure of 2 hours), there was a significant decrease in time to onset of exercise-induced angina[Gosselin 1984]. Carbon monoxide can be transported across the placental barrier, and exposure in utero constitutes a special risk to the fetus. Infants and young children are generally believed to be more susceptible to carbon monoxide than adults. The elderly are also believed to be more susceptible to carbon monoxide poisoning [Gosselin A carboxyhemoglobin level of 0.4 to 0.7 percent is normally present in the blood of adults. In cigarette smokers, the range is 4 to 20 percent, which places smokers at greater risk in exposure situations [Clayton and Clayton 1982; ACGIH 1991]. A capacity to adapt to carbon monoxide exposure has been reported in several human studies. Healthy young men exposed to carbon monoxide at a concentration of 44 ppm for a prolonged period suffered no adverse health effects [ACGIH 1986]. Men exposed to 50 ppm for several days without relief complained of headaches, but exposure to 40 ppm for 60 days was without effect [ACGIH 1986]. Workers in the Holland Tunnel working 8-hour swing shifts of 2 hours in and 2 hours out at an average carbon monoxide exposure concentration of 70 ppm had average carboxyhemoglobin levels of 5 percent, and none had levels above 10 percent [ACGIH 1991].
www.osha.gov/SLTC/healthguidelines/carbonmonoxide/recognition.html