2.1.4
Data from Joint Ontario Ministry of  the
Chromium
Environment/Environment Canada Air
3
24-hour Provincial AAQC of  1.5 µg/m
Toxics Monitoring Program
(sum of  di-, tri- and hexavalent forms)
The air toxics monitoring program in Windsor is
3
,
The annual means ranged from 0.004 to 0.010 µg/m
undertaken cooperatively by Environment Canada and
with variability from year to year with no discernible
the Ontario Ministry of  the Environment.
trend.  The maximum 24-hour average concentrations
3
varied from 0.007 to 0.296 µg/m  but most were the
3
.  These values are consider-
order of  0.01 to 0.02 µg/m
Trace Metals (in PM )
10
3
for
ably lower than the provincial objective of  1.5 µg/m
the sum of  the di-, tri- and hexavalent forms of  chro-
The 1990 IJC’s Board’s report -Air Quality on the Detroit-
mium.
Windsor/Port Huron-Sarnia Region- identified fifteen
contaminants with the highest levels of  concern relative
Lead
to direct inhalation included the following metals:
3
24-hour Provincial AAQC of  2.0 µg/m
arsenic; beryllium; cadmium; chromium; and nickel.
From a collaborative study between Environment
As observed elsewhere, the measures taken to reduce
Canada and the Ontario MOE, the levels of  some of
airborne emissions from vehicle exhaust and industrial
these trace metals, including arsenic, cadmium, and
processes have resulted in a substantial decrease in the
filters at the
chromium, were determined on PM
10
levels of  lead in urban air.  At the Windsor West (Col-
Windsor Downtown (University Ave.) site from 1990 to
lege St.) site, the annual means and the maximum
1994 and at the Windsor West (College St.) site from
concentrations measured in the second half of the
1990 to 2000.  Lead concentrations were also deter-
review period (1990-2001) were considerably lower (60
mined from PM  filters at the same sites.  Data on
10
percent lower for the means) than in the first half.
beryllium and nickel are not available.
Annual mean lead levels at that site appear to have
3
stabilized at about 0.007 µg/m .  The maximum daily
values in any year were well below the 24-hour objective.
Arsenic
3
24-hour Provincial AAQC of  0.3 µg/m
Lead is considered a criteria pollutant in the United
States.
The levels of  arsenic were observed to be rather con-
3
stant at about 0.001 to 0.002 µg/m .  The maximum 24-
3
hour values ranged from 0.003 to 0.016 µg/m  and were
3
much lower than the provincial objective of  0.3 µg/m .
2.1.5
Hazardous Air Pollutants:  Selected
Volatile Organic Compounds (VOCs)
Cadmium
The VOCs identified by the International Air Pollution
3
24-hour Provincial AAQC of  2.0 µg/m
Advisory Board for the Detroit-Windsor/Port Huron-
Sarnia Region in their 1989 report to the Commission as
The annual means for cadmium were very low, varying
having the highest level of  concern relative to direct
3
from 0.003 to 0.006 µg/m .  The annual means at the
inhalation are shown in Table 22.  Also included in this
College St site showed a small downward trend in the
table are available Ontario MOE AAQC and the U.S.
second half of the 10-year (1990-2000) review period.
EPA carcinogenic health benchmarks.  The U.S. EPA
The maximum 24-hour values varied from 0.003 to
carcinogenic health benchmark is established at a
3
0.027 µg/m .  These seem to have reached a plateau at
protective level based on the estimated risk of  one
3
0.003 µg/m .  The provincial objective for cadmium and
individual in one million possibly developing cancer after
3
its compounds is 2.0 µg/m .
a lifetime of  exposure.
27