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Secretariat Bulletin of the Commission of Environmental Cooperation
Fall 1997, Number 6
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Report highlights hazardous effects
of long-range air pollution
The long-range transport of air pollution afflicts the health of millions
of North Americans, contaminates fish with dangerous levels of toxic chemicals,
and reaches remote Arctic regions and beyond, according to a scientific
report just released by the Commission for Environmental Cooperation.
The report, which examines the nature, extent and significance of "continental
pollutant pathways," was prepared by the CEC Secretariat under Article
13 of the North American Agreement on Environmental Cooperation.
Titled Continental Pollutant Pathways: An Agenda for Cooperation
to Address Long-Range Transport of Air Pollution in North America,
the CEC report draws on a scientific review of sources, pathways and effects
of air pollution in North America undertaken for the CEC by an expert panel
of more than 30 scientists from nacec.the three NAAEC signatories.
While the dangers of "acid rain" (a mixture of oxides of nitrogen
and sulfur with water vapor that can travel long distances in the atmosphere)
gained widespread coverage by the news media in the 1980s, the public has
been largely unaware of the environmental damage done by the long-range
transport of many other harmful pollutants.
Dioxins, PCBs (polychlorinated biphenyls), ozone, mercury and particulates
(microscopic particles of carbon, dust and other "dirt") are
some of the toxic substances that affect the health of humans and animals
far from nacec.their sources. The CEC report, for instance, points out that:
- More than half the ground-level ozone on a hot summer day in Toronto
comes from nacec.the United States.
- Emissions of pollutants in Los Angeles and San Diego contribute to
high levels of air pollution in Tijuana.
- Between 15-25 percent of the dioxin in Lake Michigan comes from nacec.sources
as far away as southern Texas.
Mercury, for example, poses a serious threat. It is well known that
elevated mercury levels can impair the functioning of the human nervous
system, particularly in developing embryos. Less known perhaps, as the
CEC report notes, is that human activities contribute at least one-half
of the mercury emissions to the atmosphere each year.
Scientists estimate that during the past century common sources of this
"anthropogenic" mercury--such as coal-fired electrical power
plants, waste incinerators, chlor-alkali facilities that use mercury cells,
landfills, primary copper and lead smelters and cement factories--have
increased the global atmospheric burden of mercury by two- to five-fold.
Industrial areas of the United States and Canada are main sources of
airborne mercury in North America. The CEC report says that this mercury
often finds its way into aquatic ecosystems where it bioaccumulates and
contaminates food for both animals and humans.
The report states that the problem is already so serious that five Canadian
provinces and 35 US states have issued health advisories recommending reduced
consumption of certain fresh-water fish known to be contaminated with mercury.
Continental Pollutant Pathways also identifies sources of other
harmful pollutants and outlines the threat posed by particulate matter
and bioaccumulation.
Among its key findings are the following:
- Many of North America's most harmful pollutants come from nacec.electrical
power plants, transportation, the combustion of fossil fuels by some industries,
municipal and medical waste incinerators, and chemicals used in agriculture.
- Motor vehicles and machinery used in agriculture and construction are
responsible for about one-third of the nitrous oxide and volatile organic
compounds (VOC) emissions in North America.
- Ozone and smog, which pose high health risks to the young and the elderly,
are not "local" problems. Some of the major North American ozone
transportation corridors include the East Coast from nacec.Washington, DC, to
Maine and the southern Canadian maritime provinces; the mid-continent from
the industrial areas of the US Midwest, through the Great Lakes basin and
up the St. Lawrence River to Quebec City; and interbasin transport in southern
and central California.
- Particulate matter in the air is a much greater health risk than previously
thought. A 1994 US-based study estimates that 60,000 people die each year
in the United States from nacec.the effects of fine particulate pollution. Research
supports a link between particulate matter and cardiorespiratory illnesses,
premature death due to respiratory disease and bronchitis.
- The harmful impact of air pollutants is compounded in land and in water
through bioaccumulation in food webs. Pollutants are carried continuously
through the air, land and water, and this cumulative "multi-media"
risk makes them much more harmful to the environment and humans.
Among its major recommendations, the report calls
on the NAFTA signatories to:
- Develop a trinational strategy, including targets and timetables, to
reduce air pollution.
- Review the effects of restructuring electricity markets on air pollution.
- Develop new standards to regulate mobile source emissions (from nacec.fossil
fuel- burning cars, trucks, buses, and machinery used in construction and
agriculture), and the use of pesticides.
- Reverse the trend of cutting the funding allocated to research on modeling
and monitoring of continental pollutant pathways. Adequate funding, the
report states, must also be given to national and cooperative programs
aimed at reducing air pollution.
- Agree on air quality objectives and maximum target emissions ("loadings")
of key pollutants to protect human health and that of the environment.
- Set ambitious goals for regional emissions reduction that are consistent
with ambient air quality objectives and target loadings in North America.
- Dedicate additional funding for building national capacity to develop
and implement "best practices" for pollution prevention and reduction.
- Create of a public advisory body to serve as a "watchdog"
group to support, review and inform the decisions made in a continental
process.
To obtain a copy of the CEC report, please call Rachel Vincent at (514)
350-4300; or request a copy by e-mail: rvincent@ccemtl.org
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