Latest report on North American industrial pollution reveals impacts on our shared water environment
- Over 228 million kilograms of direct pollutant releases to surface waters were reported by industrial facilities in North America in 2006.
- In addition to direct releases to water, a minimum of 133 million kilograms of pollutants were transferred to sewage and/or wastewater treatment systems.
- Ninety percent of reported volumes released to surface waters comprised just two pollutants—nitrate compounds and ammonia—associated with nutrient loading and aquatic “dead zones” affecting North American waters.
- The report highlights sources of pollutants, including heavy metals, found in two important cross-border river systems—the Rio Grande/Río Bravo and the Columbia River watersheds.
Montreal, 12 April 2011—The 13th edition of the Taking Stock report, released today by the Commission for Environmental Cooperation (CEC), provides the most comprehensive picture of industrial pollution across North America, documenting reported releases and transfers of 5.7 billion kilograms of pollutants from facilities reporting to pollutant release and transfer register (PRTR) programs in Canada, Mexico and the United States.
This year’s report features an analysis of the more than 228 million kilograms of pollutant releases reported to surface waters across the three countries. Taking Stock reveals that just two of the 256 pollutants released to surface waters made up 90 percent of the total volume: nitrate compounds and ammonia. These pollutants are associated with the increased presence of nuisance and even toxic algal blooms that result in aquatic dead zones, or areas depleted of oxygen, increasingly affecting water bodies throughout the three countries.
In addition to direct releases to surface waters, over 133 million kilograms of a wide variety of pollutants were transferred to sewage or wastewater treatment facilities. Depending on whether and how they are treated, these pollutants can also be eventually released to surface waters.
The information on releases to surface waters also reveals significant gaps in the tracking of North American industrial pollution as a result of national reporting exemptions for certain sectors and pollutants, combined with incomplete reporting by some facilities. For example, public wastewater treatment plants accounted for 44 percent of the total reported releases, but the data come almost exclusively from Canadian facilities. In the United States, the public wastewater treatment sector is exempt from PRTR reporting and in Mexico, very few such facilities reported in 2006. Moreover, nitrate compounds and ammonia, the pollutants released in largest proportions by Canadian and US facilities, are exempt from reporting in Mexico.
“Effective regional cooperation on environmental issues depends on comparable and complete data,” said Evan Lloyd, executive director of the Commission for Environmental Cooperation. “The CEC is dedicated to supporting ongoing collaboration by our three countries to improve this information. Taking Stock and the CEC’s trinational data and analyses provide an important tool for governments, industry and citizens to address pollution and ensure healthy communities and ecosystems.”
Two case studies examine pollutant releases to the Columbia River and the Rio Grande/Río Bravo bi-national watersheds and highlight pollutants of special interest, including toxic metals such as lead, chromium and mercury and their compounds. For the first time, combining the CEC’s watershed map layer with integrated North American PRTR data makes it possible to pin-point sources of reported pollution impacting each of these shared river systems. The report shows, for example, that the majority of reported releases of two toxic metals, mercury and lead, to the Columbia and Rio Grande/Río Bravo, are from sources in Canada and Mexico, respectively.
Different reporting requirements reveal gaps
Taking Stock’s overview of pollutant releases and transfers shows that top reporting industrial sectors in North America included metal mining and activities related to the oil and gas extraction sector, fossil-fuel power plants, chemicals manufacturing, and primary metals manufacturing. However, reporting requirements for sectors and pollutants vary by country, revealing important gaps in the tracking of industrial pollution at a North American level. For example:
- The oil and gas extraction sector is exempt from reporting under the US Toxics Release Inventory (TRI), as is hydrogen sulfide (the pollutant reported in largest proportion by this same sector in Canada). Zero hydrogen sulfide emissions were reported for 2006 to Mexico’s Registro de Emisiones y Transferencia de Contaminantes (RETC) by the oil and gas extraction sector.
- Some of the toxic pollutants reported in the greatest volumes in Canada and the United States, such as carbon disulfide, zinc compounds, methanol, and hydrochloric acid, are exempt from being reported to the Mexican RETC. As a result, once these pollutants are transferred across the border—for example, when zinc is transferred from the United States to Mexico for disposal or recycling—they cannot be tracked.
Progress is being made by the governments to close these gaps—such as removing exemptions for sectors and adding substances subject to PRTR reporting. For example, Canada’s National Pollutant Release Inventory recently removed the exemption for reporting the disposal of mining tailings and waste rock. Considering the data reported in 2006 by US metal mines, this step is potentially significant to better understand the mining sector’s releases and handling of pollutants of particular concern. Metal mines in the states of Alaska, Nevada, Utah and Arizona, for example, reported releases to land—often in waste piles or uncovered areas—of millions of kilograms of heavy metals, including lead and mercury compounds, both of which are persistent, bioaccumulative and toxic pollutants.
Explore North American PRTR data online
The data presented in the Taking Stock report can be searched using the CEC’s Taking Stock Online site, which is updated annually and allows users to:
- Explore information on industrial pollutant releases and transfers;
- Generate reports in a variety of formats including pie charts and spreadsheets;
- Create maps and view them using Google Earth;
- Analyze PRTR data with respect to other information such as locations of watersheds, rivers and lakes, and population centers using geospatial data from the North American Environmental Atlas.