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CEPA 1999 Annual Report for April 2010 to March 2011


3 Information Gathering, Objectives, Guidelines and Codes of Practice (Part 3)

Part 3 of CEPA 1999 requires that the Minister of the Environment issue environmental quality objectives and guidelines, substance-release guidelines, and codes of practice. The Minister of Health is required to issue objectives, guidelines and codes of practice with respect to the elements of the environment that may affect the life and health of Canadians. Part 3 of CEPA 1999 also provides for research, information gathering, the creation of inventories, and reporting.

3.1 Environmental Quality Monitoring

In Canada, air and water quality monitoring is carried out through partnerships among provincial, territorial and federal governments, municipalities, universities, air and water associations, environmental groups, and volunteers.

3.1.1 National Air Pollution Surveillance Network

The National Air Pollution Surveillance (NAPS) network is a joint federal, provincial, territorial and municipal network established in 1969. It is primarily an urban network, with 379 reporting sites in 311 communities, complemented by the CAPMoN network's sites in rural and remote areas. The network conducts continuous measurement of ozone, nitrogen oxides (NO, NO2, NOx), sulphur dioxide (SO2), carbon monoxide, and fine and coarse particulate matter (PM2.5 and PM10, respectively), and also operates over 80 active air samplers measuring toxic substances. These include polycyclic aromatic hydrocarbons (PAHs); dioxins and furans (which are produced through combustion such as wood or biomass burning); heavy metals such as arsenic, lead and cadmium; and more than 167 volatile organic compounds (VOCs) that contribute to smog formation. More than 340 chemical substances are analyzed in samples collected at a subset of NAPS sites.

NAPS data are used to report on the achievement of the Canada-wide Standards for PM and ozone as well as the Canadian Environmental Sustainability Indicators (CESI) air quality indicators. NAPS data are also used to report on progress in reducing emissions associated with ozone and acid deposition. The report titled Canada–United States Air Quality Agreement: Progress Report 2010, published in November 2010, showed that, from 1990 to 2008, Canada's total SO2 emissions decreased by 47% and that Canada's total NOx emissions decreased by 32% in the transboundary ozone region (which includes central and southern Ontario and southern Quebec).

Continuous measurements (SO2, NO2, ozone, PM2.5 and CO) through the NAPS network are also used by Alberta, Ontario, and Quebec to report on their air quality indexes. Environment Canada and several provinces report on the Air Quality Health Index (AQHI), which uses a combination of NO2, ozone and PM2.5 measurement data to provide current hourly AQHI readings and maximum forecasted values. Continuous PM2.5 and ozone data from the NAPS network are also sent to the U.S. AirNow website to provide real-time mapping of ambient air quality across Canada and the United States.

A large number of requests for NAPS data are received annually by Environment Canada from other governments, academic researchers, and Canadians.

In 2010–2011, the NAPS program continued to upgrade data reporting and its database infrastructure to ensure timely daily and annual validated results. Carbon monoxide instruments were replaced with more sensitive trace-level analyzers capable of measuring the lower concentrations now found in most Canadian cities, and continuous PM2.5 monitors were upgraded across Canada to newer technologies in an effort to enhance consistency and comparability of fine PM data. The analysis of PM2.5 was also expanded to include levoglucosan and its isomers (mannosan, galactosan), indicators of biomass combustion (i.e., airborne particles resulting from the burning of wood from forest fires, wood stoves, wood-fired ovens, etc.). The NAPS PM2.5 network compiled its first year of levoglucosan data from 12 sites across the country.

Although concentrations of major pollutants have decreased in the last 40 years, ongoing measurements and research on health effects have made it apparent that pollutants like fine PM and ozone are still of concern. Also, the NAPS network responds to new data requirements and priorities on emerging substances of interest. For example, since 2008, in support of the CMP's monitoring and surveillance activities, PBDEs, used as flame-retardants in consumer products, have been monitored and analyzed at 10 selected NAPS sites across Canada. Of all the PBDEs monitored, results indicate that decaBDE (BDE-209) levels are the highest, especially during the colder months. This finding exemplifies the role of NAPS as a continuously evolving measurement program that provides timely, relevant and sound science in support of current and emerging air quality issues.

Although initially begun as a cooperative agreement among monitoring agencies, NAPS evolved into a formal partnership in 2004 with the endorsement of a Memorandum of Understanding between the federal, provincial, territorial and regional governments. This agreement outlined the general terms and conditions of cooperation in the overall management and support of the NAPS air quality monitoring program.

3.1.2 Canadian Air and Precipitation Monitoring Network

The Canadian Air and Precipitation Monitoring Network (CAPMoN) is a regional/remote monitoring network that has been measuring air quality since 1978. CAPMoN's 33 measurement sites are located in rural and remote areas across the country to provide a representative sampling of regional air quality, in complement to the primarily urban sites of the NAPS network. One site in the United States and another in Canada ensure the comparability of measurement methods between the two countries in support of the Canada–United States Air Quality Agreement. The network measures a wide range of air pollutants, including several toxic substances under CEPA 1999 (e.g., particulate sulphate, gaseous ammonia, nitrate, gaseous sulphur dioxide and nitric acid, ozone and mercury).

In 2010–2011, more than 25 000 samples were analyzed in support of Canadian environmental monitoring and research initiatives. Major-ion analyses (>18 000) in air and precipitation were performed to determine national critical load exceedances and ozone levels in support of the Canada-wide Standards and CESI programs. Also, continuous gas measurements in support of various research-focused air quality initiatives were continued, including for the AQHI. To ensure that timely, reliable, trace-level data are available for air quality forecasting and for the Air Quality Health Index, a study was completed in 2010 to determine which existing technology for measuring fine PM in non-urban environments is best suited to the CAPMoN network. The selected technology will be deployed in 2011–2012.

CAPMoN continues to respond to current and emerging regional/rural air quality data, information and policy priorities. Its data continue to be highly reliable and representative of remote background locations in order to support research efforts associated with regional, continental and hemispheric trends.

3.1.3 Integrated Atmospheric Deposition Network

Mandated by Annex 15 of the Canada–United States Great Lakes Water Quality Agreement, the Integrated Atmospheric Deposition Network (IADN) is a binational venture involving Environment Canada and the U.S. EPA. It was established in 1990 to monitor atmospheric trends and deposition of priority toxic pollutants in the Great Lakes Basin.

The network maintains onshore monitoring stations for each of the five Great Lakes, along with several additional satellite stations. The monitoring stations provide long-term data on regionally representative concentrations of toxic substances in gaseous, particulate and precipitation samples. Environment Canada operates stations on Lake Huron at Burnt Island and on Lake Ontario at Point Petre. Core substances monitored included PAHs, current-use and banned organochlorine pesticides, congener-specific PCBs and trace metals.

In 2010–2011, measurements of priority toxic substances, data analysis, and development and refinement of methods continued to be of importance. Core IADN substances data and trace metal data for air and precipitation are available to 2008. With support from the CMP, IADN screens air and precipitation samples for emerging substances of concern to assess their impact on the Great Lakes region. Air samples collected between 2005 and 2009 from Canadian monitoring stations were analyzed for PBDEs, and precipitation samples collected between 2007 and 2009 at sites adjacent to Lake Ontario were analyzed for PBDEs and hexabromocyclododecane (HBCD). Results are available for new flame-retardant species for air samples collected in 2009. Since 2007, precipitation samples are also being screened for new flame retardants. The data from the network continued to be used to produce peer-reviewed publications. Also, the Canadian and U.S. data between 2006 and 2008 for air and precipitation were used to calculate atmospheric deposition of core IADN substances to the Great Lakes Basin. A report entitled Atmospheric Deposition of Toxic Substances to the Great Lakes IADN Results through 2008 will be published in December 2011.

3.1.4 Northern Contaminants Program

Environment Canada continued atmospheric measurements of persistent organic pollutants (POPs), mercury and other priority chemicals in the Arctic under the Northern Contaminants Program (NCP). Led by Aboriginal Affairs and Northern Development Canada, the Northern Contaminants Program is Canada's National Implementation Plan for the Arctic Monitoring and Assessment Programme (AMAP) and contributes to Canada's obligations under the United Nations Environment Programme's (UNEP) Stockholm Convention on Persistent Organic Pollutants and UNEP's current negotiations to establish a legally binding agreement on the reduction of global mercury emissions.

POPs

The most recent temporal trends and seasonal variations in PCBs, current-use pesticides, PBDEs and polyfluorinated compounds (PFCs) measured at Alert, Nunavut, were reported in the Canadian Arctic Contaminants Assessment Report III, which isto be published in late fall 2011. This report will update information about the status of contaminants in the Canadian Arctic environment, as follows:

  • Findings indicate that atmospheric concentrations of PCBs at Alert, which were showing a declining trend prior to 2002, increased between 2003 and 2007. One possible explanation for this observation may be re-evaporation from open-ocean water as sea ice extent decreases in the summer throughout the Arctic.

  • The pesticide lindane was included in the Stockholm Convention on POPs for global control as of May 2009. Canada, a major user of lindane in North America, deregistered lindane for use on canola seeds in July 2001, and a total ban on pesticidal uses was introduced in 2004. As a result of this risk management action, the air concentration of lindane is decreasing at Alert. At the current rate of decline, the air concentration can be expected to decrease by half over the next four years.

  • PBDE levels were still increasing at Alert as of 2007. Although the highest annual levels of this contaminant are usually associated with high temperatures, episodic observations of elevated particle-bound PBDEconcentrations in the winter at Alert were likely associated with enhanced inputs through long-range transport during the Arctic-haze period, a clear manifestation of hemispheric pollution reaching the Arctic.

  • Starting in 2007, a series of new flame retardants were being screened for in air samples taken at Alert. Three new flame retardants--1,2-bis(2,4,6-tribromophenoxy)ethane, 2-ethyl-1-hexyl 2,3,4,5-tetrabromobenzoate and bis(2-ethyl-1-hexyl)tetrabromophthalate--were detected at levels comparable to levels of PBDEs. Their occurrence in air at Alert highlights their potential to be carried by air currents over long distances and reach the remote Canadian Arctic.

  • Atmospheric concentrations of precursor PFCs (fluorotelomer alcohols) and perfluorooctane sulfonamidoethanols) have been monitored at Alert since 2006. No consistent temporal trends were found for PFCs except for one of the specific fluorotelomer alcohols, which seems to exhibit a consistent increasing trend. Seasonal variations in air concentrations were observed for various PFCs.
Mercury

The most recent trends for Alert were reported in the scientific literature, in the Canadian Arctic Contaminants Assessment Report III on Mercury, and in the Arctic Monitoring and Assessment Programme update on mercury. All these findings show the need for additional monitoring locations for mercury in the Canadian Arctic to accurately assess the trends in various regions. For example, overall, the atmospheric concentration of gaseous elemental mercury was found to be lower in the western Arctic than the eastern Arctic, yet there are gaps in knowledge about the central Arctic and the sub-Arctic in Canada. Notably, concentrations of mercury species measured in the Arctic in springtime are reported to be similar to concentrations in urban and industrialized areas.

Environmental monitoring illustrates that the decrease in mercury levels in the atmosphere of the High Arctic (~0.6% per year since 1995) is much lower than that observed at lower latitudes (~3% per year). This finding suggests that emission reductions in Canada, the United States and European countries may be off-set by increasing emissions in other areas of the world such as Asia, and/or that mercury cycling in the Arctic is confounding the effect of emission reductions.

Atmospheric models of global mercury distribution indicate that the observed decline in mercury air concentrations and deposition in temperate regions of North America were attributed to declining North American mercury emissions. In contrast, models predict that mercury concentrations and deposition in the Canadian Arctic from 1990 to 2005 were influenced more by changes in global emissions and weather patterns than by changes in North American emissions.

Human exposure to contaminants in the North

Health Canada, in partnership with Aboriginal Affairs and Northern Development Canada, established the human health component of the NCP in response to concerns about human exposure to elevated levels of contaminants in wildlife species important to the traditional diets of northern Aboriginal peoples. The key objective is to reduce and, where possible, eliminate contaminants in traditional/country foods, while providing information to assist individuals and communities in making informed decisions about their consumption patterns. Biomonitoring and health outcome studies are undertaken to characterize human exposure to and the health impacts of environmental chemicals in northern populations.

The NCP currently provides Canada's main contribution to the contaminants component under the Arctic Council's Arctic Monitoring Assessment Program (AMAP). A major assessment report that improved understanding of environmental chemicals in Canada's North was published in December 2010. Health Canada contributed to the annual review of NCP proposals, resulting in eight human health projects to be conducted in 2011–2012.

Health Canada also leads the multi-year International Polar Year (IPY) dietary choice and health study in Nunavut that is increasing our understanding of the factors that determine Northern people's food choices. The project allows Health Canada to provide better risk management advice to territorial governments on contaminants and traditional foods. A synopsis of research report (of the four-year research project) was completed and accepted by the IPY Secretariat. Additionally, an educational booklet based on this study was completed for the Nunavut Arctic College. It will be used as teaching material for Northern students.

3.1.5 Intercontinental Atmospheric Transport of Anthropogenic Pollutants to the Arctic (INCATPA)

This project was one of 44 Canadian-funded projects--and one of five led by Environment Canada scientists--carried out as part of International Polar Year. The project, which ended in 2011, simultaneously measured persistent organic pollutants (POPs) and mercury concentrations in the air in potential source regions along the Pacific coasts and in the Canadian, American and Russian Arctic. The results are helping to determine the geographic sources of these chemicals, the proportion contributed by each source region, and the climatic conditions influencing their transport to the Arctic. The project was an extension of the networks for measurement of atmospheric POPs and mercury under the NCP and the Arctic Council's AMAP. The final results of the project will be summarized for the Montréal 2012 International Polar Year Conference.

In Canada, POPs and mercury are measured at stations in Alert, Nunavut, and Little Fox Lake, Yukon. Mercury in the air is also measured at Whistler, British Columbia. In 2010–2011, stations on both sides of the Pacific Ocean reported preliminary air concentration data for POPs and mercury. Most data are undergoing quality assurance/quality control to ensure consistency and reliability. Measurement results show that a group of toxic combustion by-product, polycyclic aromatic hydrocarbons (PAHs), detected in Yukon air, was related to sources in North America, Asia and northern Europe (e.g., from wildfires in California and Asia), and oil and gas production platforms throughout the Arctic. Atmospheric deposition of mercury at Alert changed between 1995 and 2007, reflecting a complex relationship between mercury deposition and local temperature and wind direction. A warming Arctic may also release POPs previously deposited in ice/snow and oceans back into the air, making them once again available for circulation around the globe and altering human and wildlife exposures. Therefore, the influence of climate change must be considered in order to reduce exposure to toxic chemicals in the Arctic.

3.1.6 Global Atmospheric Passive Sampling Network

The Global Atmospheric Passive Sampling (GAPS) Network is a global program for monitoring chemicals in the environment using simple sampling devices that require no electricity. It is a collaborative effort managed by Environment Canada scientists working with a team of international researchers. The results of the study contribute to Canada's obligations pursuant to UNEP's Stockholm Convention on Persistent Organic Pollutants, and the Protocol on POPs under the United Nations Economic Commission for Europe.

In 2010–2011, the GAPS Network continued to contribute to international efforts on atmospheric POPs through capacity building, technology transfer, data sharing, participation in workshops, and reporting. For instance, a GAPS subproject that introduced passive sampling to Indian collaborators generated the first seasonally and spatially resolved data on POPs across India.

Also in 2010, work began on a three-year UNEP-funded project to address data gaps for polychlorinated dioxins and furans in air in Latin America. Under the core GAPS work, quarterly sampling at approximately 55 global sites continued for the sixth consecutive sampling year and samples have been analyzed up to 2008. As well, new measurements conducted under the GAPS Network at a subset of 20 GAPS sites generated the first global-scale data sets and resulting publications for PFCs and volatile methyl siloxanes (VMSs). This sampling provides new information for risk assessment and risk management of these priority chemicals within Canada (e.g., CMP) and internationally, as some PFCs (perfluorooctane sulfonate (PFOS) and its precursors) have recently been added to the Stockholm Convention. Building on the success of the first phase, the second phase of the pilot study at all GAPS sites will focus on further investigating new priority chemicals in the global atmosphere in order to better understand their atmospheric transport and fate.

As the only global-scale air program under the Global Monitoring Plan of the Stockholm Convention, the data generated under the GAPS Network has modernized the integration of measurement data with global-scale emission estimates and predictions from global transport models. This has resulted in a much more integrated and comprehensive framework for evaluating chemical transport and fate in air.

3.1.7 Greenhouse Gas Monitoring

Environment Canada initiated carbon dioxide observations in 1975 as part of the global effort to characterize the changing atmospheric composition and understand climate change. The current monitoring network for greenhouse gases (GHGs) includes observations of carbon dioxide, methane, nitrous oxide, and sulphur hexafluoride. Five sites located in remote regions of Canada provide weekly and hourly concentration information for these GHGs. An additional five sites located in western Canada and central Quebec monitor carbon dioxide and methane.

The Canadian data are collected and reported in fulfillment of international obligations to the World Meteorological Organization Global Atmosphere Watch and to the Global Climate Observing System. They also meet requirements for monitoring and data sharing under the United Nations Framework Convention on Climate Change. Environment Canada's Dr. Neil Trivett Global Atmosphere Watch Observatory, located in Alert, Nunavut, is one of three global inter-comparison sites used to ensure data comparability and accuracy across the global networks. Data are used to estimate emissions from natural and anthropogenic (human-induced) sources, characterize annual variability in sources and sinks, and improve understanding of the exchange of carbon between the atmosphere and the terrestrial biosphere.

Canadian GHG concentrations and trends are consistent with global patterns. From Environment Canada's monitoring network at remote sites, annual average carbon dioxide values were 388.3 and 391.1 parts per million for 2009 and 2010, respectively, while annual average methane values were 1870 and 1874 parts per billion for 2009 and 2010, respectively.

3.1.8 Water Quality Monitoring in Support of the Clean Air Regulatory Agenda

The Freshwater Inventory and Surveillance of Mercury (FISHg) Network is a national aquatic mercury monitoring network that was established in 2008 as part of the Mercury Science Program of the Clean Air Regulatory Agenda (CARA). The network encompasses lakes across Canada that are in proximity to point-source mercury emissions, as well as reference lakes in remote regions. The results of the FISHg Network directly support the ecological risk mapping component of CARA.

In 2010–2011, five additional lakes were added to the FISHg Network (for a total of 20 sites). The additional lakes were chosen to better understand the influence of atmospheric mercury deposition on the spatial variability of mercury levels in fish. In addition to routinely monitoring mercury levels in water and fish (predatory/sport as well as forage species), the FISHg Network also collects ancillary information on other water quality parameters (e.g., sulfate, dissolved organic carbon), food-web dynamics, and watershed attributes (e.g., wetland area, catchment slope) to identify variables influencing mercury levels in each region of the country.

The initial results for the FISHg Network identified that average mercury concentrations in predatory/sport fish varied by over one order of magnitude (0.14 to 2.2 µg/g) among water bodies across the country; however, lakes in all regions contained some individual fish with mercury concentrations that were above advisory consumption levels for wildlife and humans (0.5 µg/g Health Canada guideline). Ongoing analysis of the data set is aimed at using the ancillary information collected from each lake to elucidate the variables responsible for the spatial trends. Within a given lake, mercury levels in fish increased with fish size and trophic position.

The preliminary results of this program were presented to the scientific community at the 2010 Society of Environmental Toxicology and Chemistry conference in Portland, Oregon, and at the 2011 International Conference on Mercury as a Global Pollutant in Halifax, Nova Scotia. The information generated from the FISHg Network will help establish a national baseline of mercury levels in aquatic systems, which is fundamental for evaluating the efficacy of national and international regulatory efforts and determining the impacts of changing global/transboundary atmospheric mercury concentrations on Canada's aquatic environments.

3.1.9 Water Quality Monitoring in Support of the Chemicals Management Plan

Environment Canada's national Chemicals Management Plan (CMP) Environmental Monitoring and Surveillance Program monitors chemicals in multiple environmental compartments (air, water, sediment, fish and wildlife), and also performs source monitoring (wastewater treatment plant effluents and sludge, landfill leachate and biogas). Sensitive fish species continue to be observed as part of water quality monitoring to serve as an “early warning” system for the presence of harmful substances in the ecosystem. In addition to identifying emerging substances that warrant attention, the program also enables monitoring of progression on action being taken under the CMP.

In 2010–2011, Environment Canada reported on the first nationwide study examining concentrations of PBDEs in top predatory fish, with a focus on Lake Trout. Concentrations of the three most abundant PBDE homolog groups (tetra-, penta-, and hexa-PBDEs) were, for the most part, higher in Great Lakes fish than in fish from other systems. The Canadian Federal Environmental Quality Guideline for the penta-homolog was exceeded in 70% of the fish examined. However, virtually no guideline exceedances were found for other congeners. The study also supported the continued integration of sediment sampling and focused food-web studies so as to provide information on PBDE inputs to the systems and mechanisms of biomagnifications. The ultimate aim is to better understand and communicate ecosystem responses and inform effective risk management.

As well, in 2010–2011, Environment Canada reviewed the approaches and critical factors important to contaminant biomonitoring programs in the Great Lakes in a report reviewed factors that affect the efficacy and credibility of biomonitoring programs and common methods used for dealing with them under three main categories: organism-specific factors, study design, and data analysis. Data from the literature, as well as long-term measurements of PCBs in Lake Trout sampled from Lake Ontario as part of monitoring programs conducted by Environment Canada, the Ontario Ministry of the Environment, and the U.S. EPA, were used to illustrate these factors. In general, there were several defensible methods, ranging from simple to complex, for dealing with the identified factors, with each having specific advantages and disadvantages. The importance of conducting preliminary surveys/pilot studies and regular review of ongoing programs (e.g., through a power analysis) was also emphasized.

In 2010–2011, Environment Canada continued to identify emerging contaminants and for the first time reported on the detection of perfluoroethylcyclohexanesulfonate (PFECHS) in the Great Lakes. PFECHS is a cyclic perfluorinated acid (PFA) that is mainly used as an erosion inhibitor in aircraft hydraulic fluids. For the first time, PFECHS was reported in top predator fish from the Great Lakes and in surface waters. Environment Canada also continued monitoring activities related to the presence of PFOS in the Canadian environment to contribute to the international body of knowledge on perfluorinated substances and to evaluate whether the environmental objective and risk management objective are being achieved. PFOS was the major PFA in fish sampled from the Great Lakes in 2008. Concentrations of most of the PFAs were similar to those measured in Lake Trout sampled from Lake Ontario in 2004.

In support of the Risk Management Strategy for Mercury report published by Environment Canada and Health Canada in October 2010, Environment Canada continued to monitor changes in domestic levels of mercury in water, sediment and fish in the Great Lakes Basin and other transboundary watersheds across Canada.

In 2010–2011 Environment Canada collaborated on a binational, multi-partner report on the spatial and temporal trends for mercury in fish from the Laurentian Great Lakes region. The study compiled fish mercury data from multiple sources in the Great Lakes region and assessed spatial and temporal trends in mercury concentrations in two representative top predator fish species (Walleye and Largemouth Bass). The results show a generally declining temporal trend in mercury concentrations in fish in the Great Lakes region from 1970 to 2009, with spatial trends in mercury concentrations increasing from south to north and from west to east in the region. However, mercury levels in Walleye display a flat or upward trend beginning in the 1990s. Ongoing monitoring is required to confirm a sustained decline in fish mercury levels.

In 2010, Environment Canada also collaborated with the Ontario Ministry of the Environment and the academic community to report on the temporal trends in total mercury in four fish species--Walleye, Yellow Perch, Smallmouth Bass and White Bass--in Lake Erie based on 35 years of fish contaminant data. The analysis identified a recent increase in total mercury concentrations, particularly after the mid-1990s. This finding supports the observations for Walleye described above. The analysis also shows lower decline rates and higher rates of increase in Walleye relative to the other three fish species examined. The food-web structural shifts induced by invasive species (dreissenid mussels and Round Goby) may be associated with the recent total mercury trends in Lake Erie fish. This analysis also highlights the importance of continued monitoring to inform binational reduction strategies.

3.1.10 Water Quality Monitoring for Pesticides and Pharmaceutical and Personal Care Products

Water quality monitoring and surveillance of the presence and fate of pesticides in the aquatic environment is conducted under the government's National Pesticides Science Program. This program implements Environment Canada's commitments stemming from the Pest Management Regulatory Agency-led initiative “Building Public Confidence in Pesticide Regulation,” which was associated with the December 2002 passing of the revised Pest Control Products Act. The overall objectives of the National Pesticides Science Program are to deliver pesticide surveillance, monitoring, research and assessment activities, and enhance science-based decision making regarding pesticides.

Monitoring and surveillance studies on pesticides in 2010–2011 included a national surveillance study of sulfonylurea herbicides and the herbicide glyphosate at selected agricultural sites in key national watersheds. Samples were collected from spring through late summer.

In 2010–2011, Environment Canada reported on the results of a 2007 national survey, covering 15 watersheds across Canada with varying degrees of urban land use, for a suite of 15 herbicides and one breakdown product. Six herbicides (2,4-DB, MCPB, picloram, 2,3,6-TBA, 2,4,5-T, and 2,4,5-TP(silvex)) were not detected in water samples from any sites. Herbicides detected in 2007 included dicamba, mecoprop, 2,4-D, clopyralid, bromoxynil, MCPA and dichlorprop as well as glyphosate and AMPA. Glufosinate was detected in one sample from Highland Creek, Ontario. With the exception of glyphosate, for which the highest concentrations were found in Prairie rivers, average herbicide concentrations were significantly greater in Ontario than in urban centres in other provinces. On a national basis, the concentrations of all herbicides, with the exception of dicamba, did not differ across the three seasons (spring, summer, and fall), which is likely indicative of a less seasonally focused application in urban areas compared with agricultural applications. Herbicide concentrations in urban rivers were greater during or after significant rainfall events. None of the herbicide concentrations measured in this study exceeded existing Canadian water quality guidelines for the protection of aquatic life. However, four herbicides were commonly found together in a sample, but there are currently no guidelines for herbicide mixtures or for herbicides in combination with other stressors (i.e., insecticides, nutrients, PAHs, metals and pharmaceuticals).

Concentrations of mecoprop, dichlorprop and metolachlor in Ontario streams in 2006–2007 were compared with concentrations measured in 2003–2004. Median concentrations of dichlorprop and metolachlor did not differ between the two sampling periods, but mecoprop was higher in 2006–2007. Concentrations of mecoprop and dichlorprop in Lake Ontario surface water were one to two orders of magnitude lower than average concentrations in Ontario streams. In 2003–2004, 1.2% of the samples exceeded the Canadian Council of Ministers of the Environment's (CCME) Water Quality Guideline (WQG) for mecoprop, but metolachlor did not. In 2006–2007, all samples were below the CCME guideline for mecoprop and metolachlor.

In 2010–2011, Environment Canada reported on the application of a glyphosate-based herbicide to control the Common Reed and the resulting impact on groundwater and nearshore lake water. The herbicide glyphosate was applied to reeds along a beach on the southern shore of Georgian Bay, Ontario. Groundwater and lake water were tested to determine whether glyphosate entered the groundwater and lake water at the beach and how long it persisted. Glyphosate was detected in the groundwater below the reeds two days after application, with concentrations declining rapidly over the next two to three weeks. Glyphosate was also detected in the nearshore lake water, with concentrations peaking one week after application and declining by over 70% four weeks after application. Concentrations of glyphosate never exceeded Canadian water quality guidelines in either the groundwater or lake water.

Environment Canada's surveillance of pharmaceutical and personal care products (PPCPs) in 2010–2011 included a large-scale survey of PPCPs in four watersheds in Canada. Monthly samples were collected to evaluate the influence of seasonality on concentrations and distributions.

3.1.11 Great Lakes Surveillance Program

As mandated by Annex 11 of the Canada–United States Great Lakes Water Quality Agreement, surveillance and monitoring of water quality trends is undertaken in the Great Lakes to provide information for measuring local and whole-lake responses to control measures and to assess the effectiveness of management decisions. Activities are also undertaken to determine the presence of new environmental problems in the Great Lakes Basin.

The Great Lakes Surveillance Program maintains water quality monitoring stations within each of the four Canadian Great Lakes, along with several additional stations within basin watersheds. The monitoring stations provide long-term data on regionally representative concentrations of toxic substances in water samples. Substances monitored include PAHs, current-use and banned organochlorine pesticides, congener-specific PCBs, mercury, and trace elements.

In 2010–2011, emphasis was placed on continued measurements of priority toxic substances and continued data analysis. Environment Canada reported on the concentration loads and trends in contaminants in the Niagara River from 1986 to 2005. This report was unique because it provided the first look at contaminant trends over both long and short time spans while assessing the source of the contaminant. The results indicate that, although there has been much progress over the course of the monitoring period, with a decreasing trend for many contaminants, a number of contaminants have leveled off. Notably, the PAH class of contaminants, known for their carcinogenic properties, is showing an increase in concentration.

3.1.12 Water Quality Monitoring of Transboundary Groundwater Contaminants

Since 1992, water quality sampling of groundwater on the Canadian side of the Abbotsford–Sumas aquifer has been conducted by Environment Canada, with a focus on identifying trends in nitrate concentrations in groundwater flowing from Canada to the United States (British Columbia to Washington State). Samples are routinely collected using a network of monitoring wells and analyzed for a range of inorganic water quality parameters, including dissolved nutrients and dissolved metals. The groundwater monitoring network in this aquifer has also been used for research on the persistence and fate of pesticides in groundwater settings. Nitrate concentrations on the Canadian side of the aquifer continue to be elevated and are, on average, 1.5 times higher than the maximum acceptable concentration for nitrate under the Guidelines for Canadian Drinking Water Quality, with localized areas of the aquifer showing concentrations as high as eight times the maximum acceptable concentration. Environment Canada is currently engaged in collaborative research with Agriculture and Agri-Food Canada to improve the understanding of nitrate leaching dynamics from farm fields over the aquifer and the influence of different nutrient management practices on groundwater quality. A specific area of focus for Environment Canada under this research initiative includes high-frequency (monthly) monitoring of nitrogen isotopes to examine potential nitrate source dynamics and seasonal effects of existing agricultural practices on groundwater quality. Also, Environment Canada is working with researchers from the University of Calgary on the application of diffusion samplers for detailed profiles of groundwater quality, so as to better understand how nonpoint-source agricultural contaminants propagate through this aquifer.

3.1.13 Coal Mines and Water Quality in Southeastern British Columbia

The Elk Valley in southeastern British Columbia is home to five large open-pit coal mines. Water quality impacts of this activity include the release of nitrate from explosive residue and of sulphate and selenium from waste-rock leachate to the Elk River. Concentrations of these substances have been increasing, with selenium having exceeded the CCME's Canadian water quality guidelines for the protection of aquatic life for over a decade; currently, it is increasing at a rate of approximately 10% per year. Selenium can be detrimental to egg-laying vertebrates (fish, birds, amphibians) because elevated concentrations can cause deformities or reproductive failure in affected populations. The confluence of the Elk River and the southward flowing Kootenay River is near the international boundary. The Kootenay River returns north into Canada at Creston, about 300 km downstream, where selenium levels have also been rising over the past years.

Since 2003, Environment Canada has participated in the Elk Valley Selenium Task Force. This joint industry-government group has been actively addressing the issue of selenium contamination in the valley through directed research and monitoring programs aimed at establishing effects thresholds and biogeochemical pathways and investigating potential mitigation options.

To examine the downstream attenuation of mine contaminants, a longitudinal water quality sampling program was conducted in the fall of 2010 in the Elk River headwaters and downstream to Creston. The results show that the levels of mine-related contaminants decreased sharply at the confluence with the Kootenay River and that there were no additional downstream sources.

Environment Canada participated in a workshop convened by the Society for Environmental Toxicology and Chemistry examining the state of knowledge of selenium's effects on aquatic environments. A workshop proceedings volume was published in early 2010.

3.1.14 Sensitivity of Surface Waters to Sulphur and Nitrogen Deposition

The bedrock of coastal British Columbia has a low capacity to buffer incoming acidic deposition. Although industrial emissions in the region are a fraction of those in eastern Canada, the release and deposition of reactive nitrogen and sulphur are expected to increase substantially in the future due to population growth and increased coastal marine shipping traffic. Since 2008, Environment Canada has conducted large-scale lake chemistry sampling over southwestern British Columbia to evaluate critical loads for nitrogen and sulphur deposition in water. Critical loads are thresholds below which no detrimental effects would be expected. Waters with high critical loads have high buffering capacities and therefore low sensitivity to acidic deposition. In practice, critical loads are calculated from the results of chemical analyses using any of a number of possible models. These values are then compared with empirical deposition estimates or, more often, predicted deposition fields from atmospheric models. In total, 277 lakes have been sampled, about two-thirds of which are located on the coastal mainland and the remainder on Vancouver Island. These data will make up the western component of an ongoing national aquatic critical load mapping program.

Results of the critical load research program in southwestern British Columbia were highlighted in a workshop on the effects of sulphur and nitrogen deposition in western Canada. This included important work on soil sensitivity, soil critical load mapping, aquatic critical load developments, and temporal trends in precipitation chemistry.