Pulp and paper is the third largest industrial polluter to air, water, and land in both Canada and the United States, and releases well over a hundred million kg of toxic pollution each year (National Pollutant Release Inventory, 1996). Making paper also consumes vast quantities of trees. But paper is an essential product, and we need to continue to look for improvements in pulp technology, new sources of fibre, and new technologies to get more out of the resources we use, and to avoid their use in the first place.
Kraft pulping, also known as sulphate, or chemical pulping, uses sulphur to get fibre out of trees. The sulphur chemicals account for the rotten egg smell of many pulp mills. Kraft pulping uses less than 50% of the tree. The rest ends up as sludge which is burned, spread on land or landfilled. A bonus of kraft pulping is that the chemicals can be recycled and re-used in the mill. Another is that kraft fibre is exceptionally strong ("kraft" means "strong" in German). Magazines, printing and graphics papers, grocery bags and corrugated packaging are examples of products made with kraft pulp. Kraft pulp is usually dark and is often bleached with chlorine compounds.
Mechanical pulping mills physically shred trees into pulp with grind stones and/or heat. Mechanical processes use about 90% of the tree. Unfortunately, mechanical pulp has weaker fibres, tends to discolour over time, and the process uses a lot of water and energy. Mechanical pulp is commonly used for newspapers and is often bleached with hydrogen peroxide or other chlorine-free alternatives.
Pulp mills are voracious water users. Their consumption of fresh water can seriously harm habitat near mills, reduce water levels necessary for fish, and alter water temperature, a critical environmental factor for fish. Mill owners say they are unable to institute water conservation and recycling because the concentrated effluent would kill fish (British Columbia COFI Pollution Prevention Workshop, June 1997, Environment Canada PPER Consultations, June 2000).
In British Columbia, Canada, 17 kraft mills discharge about 641 billion litres (141 billion gallons) of liquid effluent each year (Environment Canada, Environmental Effects Monitoring Report). While this liquid effluent is much less toxic than it was 10 years ago, "accidents" still kill test fish at one or two British Columbia (BC) mills nearly every month. Even after the pollution control investments of the mid-1990s, the Fraser River, BC's largest watershed and one of the best wild salmon rivers in the world, is still 1% pulp mill effluent for 600 km during winter low water!
Mill waste water continues to wreak havoc on surrounding ecosystems. In laboratory tests, mill effluent causes reproductive impairment in zooplankton, invertebrates (both these are food for fish), and shellfish (Environment Canada, Environmental Effects Monitoring Report, Cycle One). Other studies show genetic damage and immune system reactions in fish (Easton et al. 1997, Genetic Toxicity of Pulp Mill Effluent on Juvenile Chinook Salmon (Onchorhynchus shawytscha) Using Flow Cytometry, Elsevier Science Ltd., Vol. 35, #2-3).
Air pollution from pulp mills is not well studied. Mills should be, but usually are not, monitored for a range of air emissions, such as particulate matter, carbon dioxide, sulphur dioxide, hydrogen sulphide, volatile organic compounds, chlorine, chloroform, and chlorine dioxide. Incomplete data from British Columbia's Environment Ministry indicates that in 1997, mills in this Canadian province emitted 17,000 tonnes of particulates and 2.7 million tonnes of carbon dioxide, plus other unreported emissions.
Air discharges from pulp mills contain hormone-disrupting and carcinogenic
chemicals, such as chlorinated phenols, polycyclic aromatic hydrocarbons
(PAHs), and VOCs. British Columbia's coastal pulp mills are the largest
provincial source of airborne dioxins and
furans, which are among the most toxic substances known. See "
Sludge, the Triple Threat
Each Canadian mill produces an average 40 oven-dry tonnes of sludge per day, which is de-watered and then either land filled or burned. Each year, mills in the province of British Columbia create over half a million tonnes of sludge from secondary treatment plants, power boiler ash, chemical processing, waste fibre, sawmills, and other sources. Because of the different disposal methods, sludge pollutes soil, air, and water.
Many mills in Canada currently burn their sludge, but are eager to spread it on forests, parks, and farm lands as "fertilizer." Many questions remain about what is in sludge remain and rigorous testing would be required before permitting this practice. In the meantime citizens themselves are forced to deal with the issues and become Sludge Busters when there is pulp mill sludge being spread near them.
This illustrated booklet, Making Paper As If The Earth Matters, started off as a set of displays for the general public on pulp production, fibres, and clean production. Then it evolved into a tabloid newspaper, and now you can download it as a pdf file here.
To download a version for print reproduction, click here (9 MB).
The Pulp Pollution Primer, published in October 1999, explains the basics of pulp pollution, our vision for a cleaner future and explores ways to get there. The Primer is available in pdf format (384 kb).
The Production of Bleached
The US Paper Industry Association Council (PIAC) (35
allied paper product associations representing the major manufacturers
and providers of paper based communications and packaging products) has
a basic video, Paper
Recycling from Curb to Consumer, on their website at
A virtual mill tour, explaining the basics of kraft and thermomechanical
pulping, is available at the
See what BC salmon stewards say about threats to salmon and their genetic
structure, and how paper is made at