International Air Quality Advisory Board

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University of Windsor Scholarship at UWindsor International Joint Commission (IJC) Digital Archive International Joint Commission 1992-08-01 Winds of Chance: The Effects of Air Pollution on the Great Lakes International Air Quality Advisory Board Follow this and additional works at: https://scholar.uwindsor.ca/ijcarchive Recommended Citation International Air Quality Advisory Board (1992). Winds of Chance: The Effects of Air Pollution on the Great Lakes. International Joint Commission (IJC) Digital Archive. https://scholar.uwindsor.ca/ijcarchive/439 This Publication is brought to you for free and open access by the International Joint Commission at Scholarship at UWindsor. It has been accepted for inclusion in International Joint Commission (IJC) Digital Archive by an authorized administrator of Scholarship at UWindsor. For more information, please contact scholarship@uwindsor.ca.  ’ IWW4m2W4W8WInternational Joint CommissionCanada and United States/ W2;  lhe Parties, in cooperation with State and Provincial Gov- ‘ernments,‘ shall conduct research, surveillance and monitoring andimplement pollution control measures for the purpose of reducing at- ’mospheric deposition of toxic substances, particularly persistent toxicsubstances, to the Great lakes Basin Ecosystem.”Annex 15Canada - United StatesGreat lakes Water Quality Agreement, l98744444441 /992  4Wx llirborne pollutants have become increasingly recognized asl important contributors to contamination of the Great lakes. The Inter-national Air Quality Advisory Board, an advisory body to the Interna-tional Joint Commission, is attempting to gain a better understandingof long range transport of pollutants and how this contributes to thetotal burden of pollutants entering the Great lakes-St. lowrence Riverbasin.lhe International Joint Commission has a long history in as-sisting the Governments of the United States and Canada with air qual-ity matters beginning with the Trail Smelter Reference in I928.References, or assignments from the Governments, on air pollution inthe Detroit-Windsor area followed in 1949, 1966 and 1975. Underthe I966 Reference, the Commission was asked to bring to the atten-tion of Governments air pollution problems in areas along the bound-ary. The International Air Quality Advisory Board was created to assistthe Commission with this responsibility. The Commission also receiveda Reference under the Canada-ILS. Air Quality Agreement of 1991 toassist the Governments by inviting comment and preparing a synthesisof views on the biennial reports of the governments’ Air Quality Com-mittee.lhe growing awareness of the relationships between air andwater pollution has increasingly drawn the Commission into the field ofatmospheric studies. In its role of assessing and evaluating Govern-ments’ progress under the Great lakes Water Quality Agreement, theCommission tracks progress in controlling atmospheric emissions oftoxic substances that contribute to pollution of the Great lakes. TheInternational Air Quality Advisory Board and the advisory bodies estab-lished under the Great lakes Water Quality Agreement - the WaterQuality Board and Science Advisory Board - assist the Commission inthis work. A ’    7/2amsz/m  MW 0; amFor many years scientists studying pollution in the Greatlakes have been perplexed by a number of questions:0 Some Great lakes fish contain toxaphene, a pesticide used almostexclusively on cotton crops in the southern United States. How did itget to the Great lakes, hundreds of miles away?0 DDT, the dangerous pesticide that has been virtually banned in theUnited States and Canada since I972, is still turning up in samplesof Great lakes water. Is it possible the pesticide comes from hun-dreds and perhaps even thousands of miles away, from countriessouth of the Rio Grande -—- where DDT is still legally used?0 In tiny Siskiwit lake, located on Isle Royale in the northwest part oflake Superior, a variety of toxic chemicals have been found in thewater, sediment and fish. How could the chemicals have gotten to .this isolated spot? ‘Slowly, as research has continued, answers have emerged.Scientists have found that toxic substances are being carried hundredsof miles by winds and deposited in places for from their source. Forthe Great lakes, this means that some of the toxics in the water, fishand soils are not necessarily from nearby sources.t has become evident that even though pollution controlprograms around the lakes may be effective, controlling pollution fromfaraway sources is a different sort of challenge. DDT might be out-lawed in one country, for example, but its use in other countries maycause pollution many miles away and still pose a serious threat to citi-zens who thought their governments had"solved" the problem.lletermining the exact source of airborne pollution is verydifficult. unlike a river's course, which is clearly established, air move-ments are less predictable. Weather conditions, wind speed and winddirection vary, changing where airborne pollutants end up.Scientists on both sides of the Great lakes -— in theUnited States and Canada — are working together to get a better un-derstanding of how long-range transport of air pollution works. Someof this research is carried out by the International Air Quality AdvisoryBoard, an advisory body to the International Joint Commission. 7A0, 6Wll maior activity of the International Air Quality AdvisoryBoard is charting air movement patterns and determining how airbornetoxic substances end up where they do. The scientists working with theBoard have developed the concept of an "atmospheric region of influ-ence (ARO|)” — or "airshed," to use a simpler term —— to help themunderstand what happens.lhe concept of an ”airshed” is similar to that of a "water—shed”: both apply to the movements of fluids (air or water) over greatdistances. However, there are important differences.0 With an airshed, there are no fixed geographical boundaries. In-stead, its area is defined in terms of a given travel time of the airand of the probability that the air arriving at a certain place hascome from a specified area.0 yarious sites within a relatively small area might have differentairsheds.lhe aspect of time is particularly important. That’s becausedifferent pollutants stay in the air longer than others. Those that staylonger may eventually be dispersed river a much wider area than thosethat fall to the earth more quickly. For example, large particle pollut-ants such as dust, fly-ash and soot that have long been associated withurban and industrial areas, tend to settle quickly. They have otmo-spheric lifespons of only a few hours at most, and typically their im-pact is confined to areas near the source of the emissions. ~0therpollutants, however, have lifespans of many years. Some of the morefamiliar are chlorofluorocarbons, which remain in the atmosphere andstratosphere for long periods, damaging the earth’s protective ozoneshield. These pollutants are slowly dispersed over vast distances, mak-ing the atmosphere of the entire planet their "airshed."lhe atmospheric lifespans of toxic chemicals affecting theGreat lakes are usually in the median range, from several days to afew weeks. But even with what might seem a short lifespan, the pollut-‘ants can be transported hundreds of miles in the atmosphere to theGreat lakes as well as other areas. Their emission source might be farfrom the lakes. Tracking the pollutants and controlling their emissionsis difficult.    lines indicate the median location of airborne contaminants originating L3 and 5‘ days helm their arrival in the Great lolres hydrological basin.Source: International Air Quality Advisory Boarrl, l9“.* (mammal/41Wprogramme/3m        lhe atmospheric region of inﬂuence which affects the Great lakes basin islarge, encompassing nearly all of (onada and the United States. Thismeans that air pollution created almost anywhere in either country has thepotential of ending up in the Great lakes.\    ihe '_traiectory wind-rose” indicating the frequency with which air massesarrive at long Point from each directional sector.Source: international Air Duality Advisory Board, l9”.     Ward 35mmpm“lhile winds primarily arrive in the Great Lakes basin from the west, theycan come from almost anywhere, even/from the east. This is very impar-tont as strotegiesrto reduce and eliminate the atmospheric deposition ofpollutants to the Great Lakes basin are developed and put into place.  7W4WMWllcientists typically use what is called a "mass-balancemodel” to track the movement of pollutants through the environment.The model calculates the amount of a pollutant entering a designatedarea, the amount retained or transformed and the amount that leaves\ the area.llor airborne pollution the model is complicated. Pollutantsare emitted in particle or vapor form. Carried by the wind, they reach. a surface orare washed out of the atmosphere by rain or snow. Whathappens to the pollutants when they reach a surface is influenced bythe individual characteristics of each chemical or compound in the pol-lutants, as well as by the characteristics of the surface and the prevail—ing weather conditions. The texture of a surface, for example, mightcause one reaction to occur; or, in other cases, the pollutants may bechanged into quite different substances.l§ iFrom the perspective of the Great lakes, it is seldom pos-sible or practical to measure directly the amount of a pollutant depos-ited from the atmosphere (the "loading") onto the surface of a body ofwater. The calculation of "load" must be made indirectly, combiningfield and laboratory observations with theoretical modeling, and "load-ings” for each chemical or compound must be calculated separately.lhe upshot‘is that an enormous amount of data is requiredto make even moderately reliable estimates about [the "loading" of iustone chemical to one lake. ~For the past five years, climatologists at EnvironmentCanada’s Atmospheric Environment Service have been developing amethod for determining the source of airborne pollutants deposited atany designated point. The method involves using map overlays thatshow industrial and urban pollution sources, the median distance airmasses travel during a given time to the designated point, and typicalwind directions at the point. When this information is correlated withthe average atmospheric lifespan of a particular chemical or com-pound, it is possible to estimate the relative impact of emissions fromone source area on a selected "receiving" point.Continued on page Hr Isapletlts of annual concentration contribution from pollution sources locatedalongeach isopletli for an example receptor located in southern Ontario.Source: International Air Duality Advison Hoard, l m."sing mathematical models to simulate the fate and transport of atmo— 'spheric’pollutants, sources located at great distances from the Great lakeshave been found to have the potential to impact air and water quality in ‘the basin.Iairly complete information on atmospheric behaviour andlongevity is available for some chemicals —- sulfur dioxide, for ex-ample — but for many other toxic chemicals there is little informa-tion. Among the many toxic chemicals or compounds causing concernin the Great lakes region, sufficient data exist foronly four’to esti-/ mate their effect on the lakes. These are: benzo(a)pyrene, DDT, leadand PCBs.llespite this lack of information, the existing data show themagnitude of the airborne pollution problem. In the upper Greatlakes, where fewer toxics come from direct discharges or from riversflowing into the lakes, atmospheric transport of toxic pollutants has avery big effect.0 In lake Superior up to 90 percent of the new PCBs added to thelake come from the air._0 Most DDT enters lake Superior the some way, and forbenzolalpyrene and lead, atmospheric transport has an importanteffect even in the lower lakes.  041m Sam/1h Me ﬂwdlem?lhe threat to an individual’s health from pollutants travel-ing hundreds of miles may seem remote. How can a particle smallenough to be airborne for so long pose any danger?lhe answer lies in the ."behaviour" of the particles as theytravel through the air. Particles "look" for company, often picking upother particles and effectively accumulating more and more pollutantsthe longer they stay airborne. (As an example of this phenomenon,consider what happens when baking soda is placed in a refrigerator topick up odors: the particles of baking soda in the box do a good job ofabsorbing odors and other particles released by stored food, effectivelytaking smells “away” — although they still remain in some form.)Small particles have a particularly high surface-area-to-weight ratio,meaning they have greater potential to pick up other particles.lhus, airborne particles, when finally deposited, bring acomplex combination of pollutants to the surface they land on. Theymaybe a maior source of many contaminants.// 0 In 1990, in its Fifth Biennial Report on Great lakes Water Quality,the International Joint Commission said "there is a threat to the‘ health of our children emanating from our exposure to persistenttoxic substances, even at very lowambient [general] levels.”.0 A February 1992 report of the International Joint Commission on airquality in the Detroit-Windsor/Port Huron-Sarnia Region concludedthat "Sufficient information exists an airborne toxic chemicals in theregion to conclude that there is a significant public health issuewhich requires the immediate implementation of additional air emis-sion abatement and preventive measures”.lhe Great lakes can be thought of as giant pollution collec-tors. Pollutants from city sewer systems, industries and farms are car-ried into the lakes by groundwater, rivers, direct discharges and theair. Much of that pollution — such as phosphorus, which can harm fishby causing algae to bloom and lake oxygen to be depleted — can becontrolled, largely because the sources are identifiable. But toxic pol—lutants are more formidable. -0 Many toxics don’t break down easily. They are only slightly solublein water, and they cn accumulate in sediments and take manyyears to dissolve. I0 If the toxics are taken in by animals, however, they are soluble inlipid '(fat) cells, and they tendto accumulate as they move up thefood chain. Often, concentrations in the body tissue of fish and wild-life can be 10,000 to 100,000 times greater than concentrations in ‘the surrounding water.' 0 Since 1950, at least 16 species of wildlife in the Great lakes region- have been affected, at one time or another, by reproductive prob-lems or declining populations. In every case, high concentrations oftoxics were found in the animals’ tissue.lhe message is that we should be very concerned abouttoxics and should continue working towards a more complete under- ‘standing of how they enter and move around in our environment. Fur-ther research into the concept of airsheds will broaden our knowledgeof how toxics put into the air hundreds of miles away have an impor-tant effect on the Great lakes region./.2     [:1 = 0.0I < 50.0I < 100.0I < 500.0I < 1000.0> 1000.0megagrams/yearPlot ol volatile organic compound lV00 emissions for l9” showing detail for lower omission den-sity ranges. Source: Acid Deposition: State of Science and Technology, Report I, National Acid Procipitation Assessment Program.WyamomewgmIare on important class of pollutants to control. They combine with oxides ol nitro-gen to form ground level ozone, an important transboundory air pollutant. Further, some \V0(s are of concern directly because they are toxic air pollutants.           f3  ﬂame/me ﬁeeeme 0/ ﬂalweefem we gimme(percentage of total inputs) PCBs Benzo (o) pyrene    MeSW 90 96Me tel/m 73 I soweMW 53' soMe Me 13 f 79 ' ‘MeMW 7 72Summary Report of the Workshop on Great lakes AtmosphericDeposition. international Joint Commission, Windsor, Ontario,October 1987.    Math 24W?In keeping with their commitment in Annex TS of the Gre'atlakes Water Quality Agreement, the Governments of Canada and theUnited States are establishing an "Integrated Atmospheric DepositionNetwork” to develop information on how certain toxics get into theGreat Lakes and where they come from.lhe network will be in full operation by T995:0 One “master” research and monitoring site on each lake has beenset up iointly by Canada and the United States.I ‘ r v, I 0 Data gathered from experiments will be used in planning and build-ing an expanded network of up to 20 "satellite" monitoring sites.Additional stations might be necessary for special proiects, such asproposed mass balance studies for lake Michigan and a demonstra-tion program for Lake Superior. '0 Together, the "master" and “satellite” sites will create an integratedmonitoring system that will provide estimates, updated every twoyears, of airborne pollutants entering the lakes.Scientists designing the network face many challenges.They must identify the toxic substances to be monitored and design anappropiate monitoring network to allow calculations to be made ofwhere the pollutants come from. In addition, they must keep a watchfor new environmental problems by monitoring other toxic compounds.lhe development of a comprehensive and consistent moni-, toring network is critical to achieving the goals of the Great lakes Wa-ter Quality Agreement of T978. The Agreement’s overall objective isprohibiting the discharge into the lakes of toxic amounts of any sub-stance and "virtually eliminating" the discharge of all persistent toxicsubstances. Meeting this objective requires effective surveillance of thetransport of pollutants by air as well as by water./5//e often hear that many lake Superiorpollutants, and about 90 percent of some pollutants,enter via air transport . . . We would like to knowabout air deposition to lake Superior so any futurerecommendation will be based on good science.”WM25ml, /99/em, WM5% seemMammalM8W   tmospheric emissions of varied toxicw y-ltattthoen _ shown - to have a definiteWe, as citizens, must deal 

Winds of Chance: The Effects of Air Pollution on the Great Lakes

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Winds of Chance: The Effects of Air Pollution on the Great Lakes

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