Health, human carbon monoxide

National Ambient Air Quality Standards. Under the Clean Air Act, six criterion pollutants, ie, pollutants of special concern, have been estabhshed by the EPA sulfur oxides (SO ), particulates, carbon monoxide (CO), nitrogen oxides (NO ), o2one (photochemical oxidants), and lead. National Ambient Air QuaUty Standards (NAAQS) were developed by EPA based on threshold levels of air pollution below which no adverse effects could be experienced on human health or the environment. 

The effect of accumulation in various systems depends greatly on the quantity of pollutants involved. Many pollutants can be detected at concentrations lower than those necessary to affect human health. For pollutants which are eliminated slowly, individuals can be monitored over long periods of time to detect trends in body burden the results of these analyses can then be related to total pollutant exposure. Following are two examples of air pollutants that contribute to the total body burden for lead and carbon monoxide. 

The U.S. Environmental Protection Agency has established National Ambient Air Quality Standards (NAAQS) for protection of human health and welfare. These standards are defined in terms of concentration and hme span for a specific pollutant for example, the NAAQS for carbon monoxide is 9 ppmV for 8 hr, not to be exceeded more than once per year. For a state or local government to establish compliance with a National Ambient Air Quality Standard, measurements of the actual air quality must be made. To obtain these measurements, state and local governments have established stationary monitoring networks with instrumentation complying with federal specifications, as discussed in Chapter 14. The results of these measurements determine whether a given location is violating the air quality standard. 

The pollutants most strongly damaging to human, animal, and sometimes plant health include ozone, fine particulate matter, lead, nitrogen oxides (NO ), sulfur oxides (SOJ, and carbon monoxide. Many other chemicals found in polluted air can cause lesser health impacts (such as eye irritation). VOC compounds comprise the bulk of such chemicals. Formaldehyde is one commonly mentioned pollutant of this sort, as is PAN (peroxyacyl nitrate). Such... 

Industrial activity has polluted the outdoor air with a number of chemicals known to be hazardous to human health. These include a variety of gases, such as carbon monoxide, ozone, and the oxides of sulfur and nitrogen. Unacceptable levels of air pollutants can occur indoors as well. While some of these pollutants may be the same as for the outdoor air, they also include biological... 

Exposure to air pollutants can have adverse effects on human health. Exposure to one such pollutant, carbon monoxide, can result in which of the following conditions ... 

The air emissions of fossil fuel combustion are dispersed and diluted within the atmosphere, eventually falling or migrating to the surface of the Earth or ocean at various rates. Until recently, most attention was focused on the so-called primary pollutants of fossil fuel combustion that are harmful to human health oxides of sulphur and nitrogen, carbon monoxide, suspended particles (including soot), heavy metals, and products of incomplete combustion. These pollutants are most concentrated in urban or industrialized areas close to large or multiple sources. However, the primary pollutants may interact with each other, and with atmospheric constituents and sunlight, forming secondary pollutants that disperse far beyond the urban-... 

The emphasis on environmental protection in the last three decades, as industrial and economic growth gave birth to many forms of pollution threatening human health and Earth ecosystems, resulted in the growth of environmental catalysis. So, catalysts ate not only used to promote processes in the production field, but also to reduce the emissions of undesirable or hazardous compounds to the environment. For example, catalytic combustion has been proposed and developed as an effective method for controlling the emissions of hydrocarbons and carbon monoxide. 

All three gases are of particular concern for human health reasons. The TLV (8-hour average) for carbon monoxide is 5.5 mg/M, and the National Ambient Air Quality Standard (NAAQS) is 10 mg/M. No standard for divinyl sulfide has been established in the United States. However, in the Soviet Union, where toxicological research on laboratory animals indicates that divinyl sulfide is a central nervous system depressant (Trofimov and Amosova, 1984), a maximum allowable concentration (MAC) of 0.2 mg/M has been recommended (Glukharev, et al., 1980). ... 

The carbon monoxide component of the oxo reactant gases presents the most immediate human health hazard. 

Criteria pollutants are air pollutants emitted from numerous or diverse stationary or mobile sources for which National Ambient Air Quality Standards have been set to protect human health and public welfare. The original list of criteria pollutants, adopted in 1971, consisted of carbon monoxide, total suspended particulate matter, sulfur dioxide, photochemical oxidants, hydrocarbons, and nitrogen oxides. Lead was added to the list in 1976, ozone replaced photochemical oxidants in 1979, and hydrocarbons were dropped in 1983. Total suspended particulate matter was revised in 1987 to include only particles with an equivalent aerodynamic particle diameter of less than or equal to 10 micrometers (PM10). A separate standard for particles with an equivalent aerodynamic particle diameter of less than or equal to 2.5 micrometers (PM25) was adopted in 1997. 

On the basis of its review of human and experimental animal health-effects and related data, the subcommittee concludes that the Navy s proposed SEAL 1 of 75 ppm for carbon monoxide is too conservative. The subcommittee rec... 

On the basis of its review of human and experimental animal health-effects and related data, the subcommittee concludes that the Navy s proposed SEAL 2 of 85 ppm for carbon monoxide is too conservative. The subcommittee recommends a SEAL 2 of 150 ppm, which would not result in blood COHb concentration above 20%. Human data suggest that at a COHb concentration of approximately 20%, some submariners could experience mild headache and some decrement in cognitive function (Schulte 1963 Parving 1972 Stewart et al. 1973). Such effects would not impair the ability of a crew to escape from a disabled submarine. The recommended SEAL 2 is also supported by Theodore et al. (1971) where monkeys were exposed to a carbon monoxide concentration of 380 ppm for 90 d (COHb=31%) and there were no adverse health effects. 

Horvath, S.M., T.E.Dahms, and I.F.O=Hanlon. 1971. Carbon monoxide and human vigilance a deleterious effect of present urban concentrations. Arch. Environ. Health 23(5) 343-347. Horvath, S.M., P.B.Raven, T.E.Dahms, and D.I.Gray. 1975. Maximal aerobic capacity at different levels of carboxyhemoglobin. J. Appl. Physiol. 38(2) 300-303. 

Purser, D.A., and K.R.Berrill. 1983. Effects of carbon monoxide on behavior in monkeys in relation to human fire hazard. Arch. Environ. Health 38(5) 308-315. 

Stewart, R.D., J.E.Peterson, E.D.Baretta, R.T.Bachand, M.J.Hosko, and A.A. Herrmann. 1970. Experimental human exposure to carbon monoxide. Arch. Environ. Health. 21(2) 154-164. 

National Ambient Air QuaHty Standards (NAAQS) have been estabHshed for ozone (qv), nitrogen oxides, lead (qv), carbon monoxide (qv), sulfur dioxide, and particulates. The standards have been set to safeguard human health and the environment. Many areas of the country violate one or more of the NAAQS. To achieve healthful air for all citizens, the states estabHsh an implementation plan for each area that violates the NAAQS for any of the six criteria pollutants. The plan is a strategy designed to achieve sufficient emission reductions to meet the NAAQS within the deadline. Based on the implementation plan, specific regulations are written which govern the operations emitting the pollutant. 

Most BEIs are defined as concentrations of determinants or biomarkers anticipated in biological specimens collected from healthy workers whose exposure to certain chemicals by all routes is equivalent to that of workers with inhalation only exposure at the OEL. Others measure reversible effects on the body, and still others are those that are below the concentrations associated with health effects. However, other definitions are common. For example, the German biological tolerance values (BAT) can be defined as rates of excretion of the chemical or its metabolites, or the maximum possible deviation from the norm of biological parameters induced by these substances in exposed humans. BEIs for some chemicals use other criteria, such as direct comparison with a measurable toxic effect, like carboxyhemoglobin in blood for carbon monoxide. 

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