Sources
Carbon Monoxide (CO)
Motor vehicles are the dominant source.  Fossil fuel
combustion from electrical utility, industrial, com-
Formed
mercial, and residential sources, as well as steel and
Carbon monoxide is formed by the incomplete
iron manufacturing also contribute to emissions.
combustion of fossil fuel, mainly from mobile
sources.  Additional sources include: heating,
Effects
industrial process, and electrical generation.
CO affects the human central nervous system by
limiting oxygen distribution to the body (Ref. 9).
Concentrations in urban areas depend principally
upon traffic density, topography, and weather
conditions.
Standards/Criteria
TABLE 5
Standards (Michigan) / Criteria (Ontario) for Carbon Monoxide
Michigan (U.S. EPA NAAQS)
Pollutant
Primary (Health Related)
Secondary
CO
8-hour
9 ppm
No Secondary Standard
3
)
(10mg/m
Not to be exceeded more than once per year
1-hour
35 ppm
3
)
(40mg/m
Not to be exceeded more than  once per year
Ontario (MOE)
Pollutant
Criteria
CO
8-hour
13 ppm
1-hour average
30 ppm
The size of  the particle affects its deposition in the
Particulate Matter: Total Suspended Particu-
human respiratory tract and consequently its potential to
lates (TSP); (Inhalable Particulate Matter
impair health.  Smaller particles are believed to pose the
); and Respirable Particulate Matter
(PM
10
greatest health risk due to their deposition deep in the
(PM )
2.5
human respiratory track (Ref. 10).
Particulate matter can include dust, dirt, smoke, soot and
liquid droplets (aerosols) and can originate from a
Total Suspended Particulate (TSP)
variety of  natural and anthropogenic sources.  Two
classes of  airborne particulate matter are of  particular
In addition to the PM  and PM  AAQC, Ontario also
importance to human health; fine/respirable particulate
10
2.5
has AAQC for Total Suspended Particulate Matter.
matter (PM  - particles 2.5 µm (microns) in diameter or
2.5
Total suspended particulate includes particles of  various
smaller) or coarse/inhalable particulate matter (PM  -
10
sizes.  Some proportion of  TSP consists of  particles too
particles 2.5 to less than 10 µm in diameter).  Total
large to enter the respiratory tract; therefore, TSP is not
Suspended Particulates (TSP) includes both PM  and
10
considered a good indicator of  health-related exposure.
PM  as well as larger particles (typically up to 40 µm).
2.5
10