Paper or plastic bags: which is better?
It's an age old question, when it comes time to check out when grocery shopping:paper bag or plastic bag? It seems like it should be an easy choice, but there's an incredible number of details and inputs hidden in each bag. From durability and reusability to life cycle costs, there's a lot more to each bag than meet the eye. Let's take a look behind the bags.
Where do brown paper bags come from?
Paper comes from trees -- lots and lots of trees. The logging industry, influenced by companies like Weyerhaeuser and Kimberly-Clark, is huge, and the process to get that paper bag to the grocery store is long, sordid and exacts a heavy toll on the planet. First, the trees are found, marked and felled in a process that all too often involves clear-cutting, resulting in massive habitat destruction and long-term ecological damage.
Mega-machinery comes in to remove the logs from what used to be forest, either by logging trucks or even helicopters in more remote areas. This machinery requires fossil fuel to operate and roads to drive on, and, when done unsustainably, logging even a small area has a large impact on the entire ecological chain in surrounding areas.
Once the trees are collected, they must dry at least three years before they can be used. More machinery is used to strip the bark, which is then chipped into one-inch squares and cooked under tremendous heat and pressure. This wood stew is then "digested," with a chemical mixture of limestone and acid, and after several hours of cooking, what was once wood becomes pulp. It takes approximately three tons of wood chips to make one ton of pulp.
The pulp is then washed and bleached; both stages require thousands of gallons of clean water. Coloring is added to more water, and is then combined in a ratio of 1 part pulp to 400 parts water, to make paper. The pulp/water mixture is dumped into a web of bronze wires, and the water showers through, leaving the pulp, which, in turn, is rolled into paper.
Whew! And that's just to make the paper; don't forget about the energy inputs -- chemical, electrical, and fossil fuel-based -- used to transport the raw material, turn the paper into a bag and then transport the finished paper bag all over the world.
Where do paper shopping bags go when you're done with them?
When you're done using paper shopping bags, for shopping or other household reuses, a couple of things can happen. If minimally-inked (or printed with soy or other veggie-based inks) they can be composted; otherwise, they can be recycled in most mixed-paper recycling schemes, or they can be thrown away (which is not something we recommend).
If you compost them, the bags break down and go from paper to a rich soil nutrient over a period of a couple of months; if you throw them away, they'll eventually break down of the period of many, many years (and without the handy benefits that compost can provide). If you choose to recycle paper bags, then things get a little tricky.
The paper must first be re-pulped, which usually requires a chemical process involving compounds like hydrogen peroxide, sodium silicate and sodium hydroxide, which bleach and separate the pulp fibers. The fibers are then cleaned and screened to be sure they're free of anything that would contaminate the paper-making process, and are then washed to remove any leftover ink before being pressed and rolled into paper, as before.
How are plastic bags made?
Unlike paper bags, plastic bags are typically made from oil, a non-renewable resource. Plastics are a by-product of the oil-refining process, accounting for about four percent of oil production around the globe. The biggest energy input is from the plastic bag creation process is electricity, which, in this country, comes from coal-burning power plants at least half of the time; the process requires enough juice to heat the oil up to 750 degrees Fahrenheit, where it can be separated into its various components and molded into polymers. Plastic bags most often come from one of the five types of polymers -- polyethylene -- in its low-density form (LDPE), which is also known as #4 plastic.
How does plastic bag recycling work?
Like paper, plastic can be recycled, but it isn't simple or easy. Recycling involves essentially re-melting the bags and re-casting the plastic, though, according to the U.S.EPA, manufacturing new plastic from recycled plastic requires two-thirds of the energy used in virgin plastic manufacturing. But, as any chef who has ever tried to re-heat a Hollondaise sauce will tell you, the quality isn't quite as good the second time around; the polymer chains often separate break (thanks to reader MaryBeth for noting the difference between "separate" and "break" -- the former implies that the chains can come back together, which they can't), leading to a lower-quality product.
What does that mean to you? Basically, plastic is often downcycled -- that is, the material loses viability and/or value in the process of recycling -- into less functional forms, making it hard to make new plastic bags out of old plastic bags.
What about biodegradable plastic bags?
Biodegradable plastic is a mixed bag (pun intended) as well; while biopolymers like polyhydroxyalkanoate (PHA) and Polylactide (PLA) are completely biodegradable in compost (and very, very, very slowly -- if at all -- in a landfill) and are not made from petroleum products, they are often derived from our food sources.
The primary feedstock for bioplastics today is corn, which is rife with agro-political conflict and often grown and harvested unsustainably; because of these reasons, and because it competes with food supply, it is not likely to be a long-term solution in the plastics world.
Plus, some bags marked "biodegradable" are not actually so -- they're recycled plastic mixed with cornstarch. The cornstarch biodegrades and the plastic breaks down into tiny little pieces but does not actually "biodegrade," leaving a yucky polymer mess (if in small pieces). The only way to avoid this? Look for 100% plant-based polymers, like the two mentioned above.
So, while it's good to have the alternative (and to recognize the innovation it represents), bioplastics aren't quite ready to save us from the paper or plastic debate.
Paper or plastic: A look at the facts and numbers
Further insight into the implications of using and recycling each kind of bag can be gained from looking at overall energy, emissions, and other life cycle-related costs of production and recycling. According to a life cycle analysis by Franklin Associates, Ltd, plastic bags create fewer airborne emissions and require less energy during the life cycle of both types of bags per 10,000 equivalent uses -- plastic creates 9.1 cubic pounds of solid waste vs. 45.8 cubic pounds for paper; plastic creates 17.9 pounds of atmospheric emissions vs. 64.2 pounds for paper; plastic creates 1.8 pounds of waterborne waste vs. 31.2 pounds for paper.
Paper bags can hold more stuff per bag -- anywhere from 50 percent to 400 percent more, depending on how they're packed, since they hold more volume and are sturdier. The numbers here assume that each paper bag holds 50 percent more than each plastic bag, meaning that it takes one and half plastic bags to equal a paper bag -- it's not a one-to-one comparison, even though plastic still comes out ahead.
It's important to note that all of the above numbers assume that none of the bags are recycled, which adds a lot of negative impacts for both the paper and plastic bags; the numbers decrease in size (and the relative impacts decrease) as more bags are recycled. Interestingly, the numbers for paper bag recycling get better faster -- the more that are recycled, the lower their overall environmental impact -- but, because plastic bags use much less to begin with, they still ends up creating less solid and waterborne waste and airborne emissions.
Paper and plastic bags' required energy inputs
From the same analysis, we learn that plastic also has lower energy requirements -- these numbers are expressed in millions of British thermal units (Btus) per 10,000 bags, again at 1.5 plastic bags for every one paper bag. Plastic bags require 9.7 million Btus, vs. 16.3 for paper bags at zero percent recycling; even at 100% recycling rates, plastic bags still require less -- 7.0 to paper's 9.1. What does that mean to me and you? Plastic bags just take less energy to create, which is significant because so much of our energy comes from dirty sources like coal and petroleum.
Paper bags or plastic bags: the conclusion
Both paper and plastic bags require lots and lots of resources and energy, and proper recycling requires due diligence from both consumer and municipal waste collector or private recycling company, so there are a lot of variables that can lead to low recycling rates.
Ultimately, neither paper nor plastic bags are the best choice; we think choosing reusable canvas bags instead is the way to go. From an energy standpoint, according to this Australian study (Ref: http://www.environment.gov.au/settlements/publications/waste/plastic-bags/analysis.html), canvas bags are 14 times better than plastic bags and 39 times better than paper bags, assuming that canvas bags get a good workout and are used 500 times during their life cycle. Happy shopping!
Paper Bags vs Plastic Bags
My post about the environmental impact of plastic bags attracted a fair comment about the impact of paper bags on the environment. It seems that many people are using paper bags in the belief that they are better for the natural environment than plastic bags.
Unfortunately, that’s not necessarily true - paper bags are just as bad as plastic bags when it comes to the environment. In fact, some say paper bags are worse than plastic bags.
Some Facts and Figures
Here are some facts and figures according to reusable bags, regarding paper bags vs plastic bags:
So, according to these figures paper bags are much worse than plastic bags right? Sure does sound like it.
But then, you also need to take into account things such as size differences and usage patterns between the two bags. For example, paper grocery bags are usually larger than their plastic counter parts, so you need less of them. Also, there are different recycling rates between the two, which will affect the actual damage to the environment.
In 1990, Franklin and Associates completed a life-cycle energy analysis to consider all this and still concluded that the plastic bag was the better bag.
OK, so even though the plastic bag was the better bag, we all know how bad the plastic bag really is on the natural environment!
A Much Better Bag
So, the best thing to do is to avoid paper and plastic bags altogether. Instead, opt for a reusable bag made from a natural fiber.
Ideally, your reusable bag would be large enough to fit 5 times the groceries that a plastic bag would. Also, it would be so durable, that you can continue to reuse it for 2 - 3 years without needing to replace it.
Think of how many plastic or paper bags you’d be saving by doing that!
But one element British shoppers would find distinctly foreign is the need to pay for plastic bags at the checkout.
Since the beginning of March, supermarkets have been forced to charge shoppers a 15c (9p) tax on each new plastic bag.
The idea was introduced as an attempt to curb the litter problem created by so many bags. And anecdotally, at least, it seems to be working.
Within a couple of months, shoppers have switched to re-using carrier bags. Customers now routinely turn up "pre-armed" with a clutch of polythene and one of the biggest chains, Superquinn, says the number of bags it distributes has dropped by 97.5%.
Being thoughtless
Now there is speculation that the UK could follow suit. Environment minister Michael Meacher is said to be interested in the scheme and the environment department says it has "concerns about the number of plastic bags that are routinely handed over by supermarkets".
It's not just litter that is the problem. Environmentalists decry our thoughtless reliance on plastic bags - Britons get through eight billion a year, equivalent to 133 per person.
Made of polyethylene - more commonly known as polythene - they are hazardous to manufacture and are said to take up to 1,000 years to decompose.
Elsewhere in the world, their role in environmental destruction is even more drastic and so, it seems, a revolt has begun against the humble plastic bag.
In March, Bangladesh slapped an outright ban on all polythene bags after they were found to have been the main culprit during the 1988 and 1998 floods that submerged two-thirds of the country. The problem was that discarded bags were choking the drainage system
'Plastic flower'
Taiwan is moving to ban the free distribution of plastic bags, while, next month, the government in Singapore will launch a campaign to discourage their use.
In India, cows are ingesting plastic bags as they forage for food on the street. They then end up choking or starving to death. The same happens to turtles, which commonly mistake plastic bags for jellyfish, say environmentalists.
In South Africa, they have been dubbed the "national flower" because so many can be seen flapping from fences and caught in bushes.
They are even big in America, despite all those Hollywood films featuring "moms", returning from the supermarket, overburdened with paper bags. Four out of five grocery bags in the US are now plastic.
From paper to plastic
Yet this trend is a fairly recent phenomenon; the result of advancements in manufacturing.
Thirty years ago paper still ruled. In the UK, the switch to plastic was a result of growing competition in the supermarket sector, says Dr Graham Godwin, a former technical executive at Marks and Spencer.
"Plastic was the material of choice in those days and it was more hygienic, if for example something spilt as you carried your shopping home."
It is also stronger and faired better in the damp British climate.
Crucially, however, plastic bags have become cheaper than paper. The so called "T-shirt" bags that are freely available at supermarkets are made of lightweight, high-density polythene.
'A people problem'
They cost and weigh a fraction of the older and thicker, stretchy polythene bag that shops used to charge for.
So has the bottom finally fallen out of the plastic bag market?
Not surprisingly, those with a stake in the industry deny reports of its demise. The fault is with human behaviour, not the bags themselves, says Peter Woodall of the Packaging and Industrial Films Association.
"Lots of people recycle them as bin bags. If you make people pay for them, they will have to go out and buy separate bin bags," says Mr Woodall.
"Plastic requires a great deal less energy in manufacturing than paper and because the vast majority of our plastic bags are imported from Asia, a switch back to heavier paper bags, means it would take more energy to bring them over."
So for the meantime at least, British shoppers will continue to see plastic as fantastic.
Source: http://news.bbc.co.uk/2/hi/uk_news/1974750.stm
The world's rubbish dump: a tip that stretches from Hawaii to Japan
A "plastic soup" of waste floating in the Pacific Ocean is growing at an alarming rate and now covers an area twice the size of the continental United States, scientists have said.
The vast expanse of debris – in effect the world's largest rubbish dump – is held in place by swirling underwater currents. This drifting "soup" stretches from about 500 nautical miles off the Californian coast, across the northern Pacific, past Hawaii and almost as far as Japan.
Charles Moore, an American oceanographer who discovered the "Great Pacific Garbage Patch" or "trash vortex", believes that about 100 million tons of flotsam are circulating in the region. Marcus Eriksen, a research director of the US-based Algalita Marine Research Foundation, which Mr Moore founded, said yesterday: "The original idea that people had was that it was an island of plastic garbage that you could almost walk on. It is not quite like that. It is almost like a plastic soup. It is endless for an area that is maybe twice the size as continental United States."
Curtis Ebbesmeyer, an oceanographer and leading authority on flotsam, has tracked the build-up of plastics in the seas for more than 15 years and compares the trash vortex to a living entity: "It moves around like a big animal without a leash." When that animal comes close to land, as it does at the Hawaiian archipelago, the results are dramatic. "The garbage patch barfs, and you get a beach covered with this confetti of plastic," he added.
The "soup" is actually two linked areas, either side of the islands of Hawaii, known as the Western and Eastern Pacific Garbage Patches. About one-fifth of the junk – which includes everything from footballs and kayaks to Lego blocks and carrier bags – is thrown off ships or oil platforms. The rest comes from land.
Mr Moore, a former sailor, came across the sea of waste by chance in 1997, while taking a short cut home from a Los Angeles to Hawaii yacht race. He had steered his craft into the "North Pacific gyre" – a vortex where the ocean circulates slowly because of little wind and extreme high pressure systems. Usually sailors avoid it.
He was astonished to find himself surrounded by rubbish, day after day, thousands of miles from land. "Every time I came on deck, there was trash floating by," he said in an interview. "How could we have fouled such a huge area? How could this go on for a week?"
Mr Moore, the heir to a family fortune from the oil industry, subsequently sold his business interests and became an environmental activist. He warned yesterday that unless consumers cut back on their use of disposable plastics, the plastic stew would double in size over the next decade.
Professor David Karl, an oceanographer at the University of Hawaii, said more research was needed to establish the size and nature of the plastic soup but that there was "no reason to doubt" Algalita's findings.
"After all, the plastic trash is going somewhere and it is about time we get a full accounting of the distribution of plastic in the marine ecosystem and especially its fate and impact on marine ecosystems."
Professor Karl is co-ordinating an expedition with Algalita in search of the garbage patch later this year and believes the expanse of junk actually represents a new habitat. Historically, rubbish that ends up in oceanic gyres has biodegraded. But modern plastics are so durable that objects half-a-century old have been found in the north Pacific dump. "Every little piece of plastic manufactured in the past 50 years that made it into the ocean is still out there somewhere," said Tony Andrady, a chemist with the US-based Research Triangle Institute.
Mr Moore said that because the sea of rubbish is translucent and lies just below the water's surface, it is not detectable in satellite photographs. "You only see it from the bows of ships," he said.
According to the UN Environment Programme, plastic debris causes the deaths of more than a million seabirds every year, as well as more than 100,000 marine mammals. Syringes, cigarette lighters and toothbrushes have been found inside the stomachs of dead seabirds, which mistake them for food.
Plastic is believed to constitute 90 per cent of all rubbish floating in the oceans. The UN Environment Programme estimated in 2006 that every square mile of ocean contains 46,000 pieces of floating plastic,
Dr Eriksen said the slowly rotating mass of rubbish-laden water poses a risk to human health, too. Hundreds of millions of tiny plastic pellets, or nurdles – the raw materials for the plastic industry – are lost or spilled every year, working their way into the sea. These pollutants act as chemical sponges attracting man-made chemicals such as hydrocarbons and the pesticide DDT. They then enter the food chain. "What goes into the ocean goes into these animals and onto your dinner plate. It's that simple," said Dr Eriksen.
Source: by Kathy Martks, Asia-Pacific Correspondent, and Deniel Howden
Environmental Impacts of the Paper Industry
Wisconsin is the United State's largest paper producer, and has been for years. Pulp and Paper companies also constitute the largest manufacturing sector in the state, providing thousands of high-paid jobs. Unfortunately, the environment, and our democracy, has suffered because of it.
Damage Caused by the Paper Industry
Contaminated Sediments, Fish & Ducks --- The paper industry has been a major source of accumulated toxic chemicals in several rivers in Wisconsin, most notably of PCBs to the Fox River and Green Bay system in Northeast Wisconsin. Clean Water Action Council has been fighting 18 years to get the Fox River PCB sediment contamination cleaned up, but in the last seven miles of the river, the DNR and EPA recently chose a cleanup target which will leave the river and bay unhealthy for another 55-100+ years.
Continuing Toxic Pollution --- The paper industry is a major source of toxic chemical pollution in Wisconsin. The federal and state Toxic Release Inventories shows releases of approximately 14 million pounds of known toxic substances in 1996. Modest reductions in chemical use over the years (per unit of production) seem to be countered by increased production.
Many toxic chemicals are used in paper making, especially toxic solvents and chlorine compounds used to bleach and delignify pulp. Additional toxins are used as biocides to prevent bacterial growth in the pulp and finished paper products. (In the past, toxic mercury compounds were used as biocides, contributing to Wisconsin's mercury contamination problems in fish.)
Conventional Air Pollution --- Pulp and paper mills are large sources of standard air pollutants, such as carbon dioxide, nitrous oxides, sulfur dioxides, carbon monoxides and particulates. These contribute to ozone warnings, acid rain, global warming and respiratory problems. Many of the mills are large enough to have their own coal-fired power plants, raising additional concerns about mercury, arsenic and radioactive emissions.
Energy Consumption --- Paper making is energy intensive, drawing larges amount of electricity from public utilities, or forcing mills to build their own power plants. This is a signficant contributor to the air pollution in our region, and to the hidden damages due to fuel extraction at the source (oil drilling, oil spills, coal mining, pipelines, transmission lines, etc.)
Water Consumption --- Paper making uses a great deal of water, frequently from diminishing groundwater supplies. In the Green Bay area, the aquifer drawdown caused by excessive high capacity wells of the paper industry are a major cause of our municipal water woes, forcing local taxpayers to build expensive pipelines 30 miles to Lake Michigan. The Aquifer Storage and Recovery proposal is also partly due to water consumption by the paper industry.
Solid Waste --- Paper making generally produces a large amount of solid waste. Unfortunately, landfilling costs in Northeast Wisconsin are relatively cheap (often less than $20 per ton), so the industry has little incentive for making more efficient use of its materials. Because we have so many paper recycling industries in our area, an even larger quantity of waste is generated. Paper fibers can be recycled only a limited number of times before they become too short or weak to make high quality paper. This means the broken, low- quality fibers are separated out to become waste sludge. All the inks, dyes, coatings, pigments, staples and "stickies" (tape, plastic films, etc.) are also washed off the recycled fibers to join the waste solids. The shiney finish on glossy magazine-type paper is produced using a fine kaolin clay coating, which also becomes solid waste during recycling. These paper mill sludges consume a large percentage of our local landfill space each year. Worse yet, some of the wastes are landspread on cropland as a disposal technique, raising concerns about trace contaminants building up in soil or running off into area lakes and streams. Some companies burn their sludge in incinerators, contributing to our serious air pollution problems.
Deforestation --- Worldwide, enormous tracts of virgin forest are being felled for paper pulp production, contributing to the world's tragic deforestation trends. Many Wisconsin mills import their pulp and undoubtedly some of this pulp came from old-growth endangered forests. Citizen networks have formed worldwide in an effort to save the last of these precious, irreplacable places. (Trees may be renewable, but ancient forest plant and animal communities are often not renewable because of the complex ecological balance which was built over thousands, even millions, of years in some of these forests.)
Corruption of Democracy --- Paper is king in Wisconsin, literally. For many decades, the industry has been pampered by local, state and federal governments -- with tax breaks, energy breaks, incentive grants, university research projects, employee training programs, cheap water, cheap pulpwood, cheap landfills, and other generous subsidies. The paper industry is not an example of "free enterprise" or "capitalism," rather, it is fascism, the corporate control of government. The paper industry gives generously to political campaigns, and is rewarded. Most recently, the Wisconsin Paper Council's requests have been granted for a $45 million tax break (in the middle of record-breaking deficits), further energy breaks, and the Governor's promise of "streamlined" environmental permitting (heaven help us...) For 30 years, the paper industry successfully blocked the Fox River PCB cleanup, and they've been extremely influencial in weakening Wisconsin's air, water and solid waste regulations since the beginnings of those programs. Any time a new environmental standard is proposed, the paper industry lobbyists are there, often in large numbers, to protect the paper industry from its responsibilities. Politicans provide no leadership. It appears that the Republicans are more concerned with protecting the corporations, while the Democrats are more concerned with labor unions and protecting paper worker jobs. Neither seems to care about the bigger picture of public health protection, natural resource conservation or environmental sustainability.
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.
Water Pollution
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
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 below"Big Pulp's Dirty Little Secret: Coastal pulp mills create one-fifth of all the dioxin in Canada," in the Watershed Sentinel.
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.
Source: http://www.rfu.org/cacw/basic.html
Big Pulp's Dirty Little Secret - Coastal pulp mills create one-fifth of all the dioxin in Canada.
They still make dioxin in paradise. On the coast of BC traditionally logs are boomed and transported in salt water, soaking in salt on the trip and during storage. Coastal pulp mills burn bark and sawmill waste ("hog fuel") in their power boilers to make energy to run the mill.
When the "salty hog fuel" is burned, it makes dioxin, because the chlorine in the salt combines with carbon from the wood when it is burned. In fact, despite the clean-up of most of the dioxin from bleaching--an unrelated issue--eight coastal pulp mills are still creating one-fifth or more of all the dioxin in Canada!
A small amount (about 8.5 grams annually) is released into the air from the boiler smokestack. The rest (over 100 grams a year) goes into the ash and then into the mill landfills. Only some landfills have liners or collect all the contaminated leachate.
Further, some mills' landfills are filling up, and the mills want to spread their sludge and ash on farm land and forests. Incomprehensibly, in just one of dozens of failures in a wildly-inaccurate inventory, Environment Canada classifies this dioxin-contaminated ash as a "product" because, in theory, it is not released to the environment.
How much dioxin is this?
It sounds like a small amount, but the Canadian federal government has been saying since 1995 that dioxin should be "virtually eliminated" because it is so dangerous to human health and the environment.
Dioxin is normally measured in nanograms or picograms; one nanogram is a trillionth of a gram and one picogram is one quadrillionth of a gram. Although these seem like very small concentrations, it adds perspective to realize that hormones enact major changes in the human body at concentrations of one part per trillion.
Japanese scientists say 17 grams of dioxin would be enough to kill 14 million rats!
Some of the other large sources of airborne dioxin in Canada are "teepee" garbage burners in Newfoundland. Municipal incinerators have been closed in most Canadian jurisdictions, leaving hospital incinerators as major sources. Residential wood and fuel combustion, diesel fuel, the steel industry, cement kilns, all release dioxins into the air.
Despite their process changes, pulp mills are estimated to put almost five grams a year into Canadian waters--although this is a significant improvement over the 1990 levels of 450 grams, which resulted in extensive fisheries closures. Pesticides and sewage sludge put an unknown amount of dioxin into the soil and thus into the food chain.
What is the government doing?
Domestically, there have been a lot of meetings. Enviros have raged, and industry has stonewalled. Incinerators have been closed.
At the end of the day, a "Canada Wide Standard" will be brought to a meeting of the provincial and federal ministers of environment for consensus on some emissions levels for how much dioxin various industries should be allowed to make. They will call this "Virtual Elimination" because it will be prefaced with a statement that, in the end, eventually, in about 25 years, or some time later, Canada wants to stop making dioxin.
On an international level, Canada has promoted an international UN treaty on POPs because they concentrate in the Arctic. However, the Canadian and American delegations are negotiating for a weak treaty which will:
Japanese scientists say 17 grams of dioxin would be enough to kill 14 million rats.
It's not too healthy for people, either.
Health effects for adults include skin disease, immunosuppression, respiratory and cardiovascular, and liver problems, reproductive toxicity, and probable carcinogenicity.
The problems for a fetus could include learning behaviour, development of the reproductive system and the immune system.
* USEPA 1999
Environmentalists and some European countries argue for elimination by using alternative technologies to stop the industrial creation of these toxic by-products, rather than attempts to control emissions. Because dioxin is so persistent, the continual creation of new dioxin means a continual, global, problem with disposal of contaminated ash.
Tight emission standard proposed
Here in BC, the Council of Forest Industries has generously proposed a tight emission standard on any new power boilers built for aging coastal pulp mills. However, the catch is that there are not likely to be any more $100 million boilers built.
COFI further suggests that the two worst offenders, the Fletcher Challenge Canada mills at Elk Falls and Crofton, may halve their emissions by 2005 through some remedial work on the boilers, adding such "end-of-pipe" fixes as a wet electrostatic precipitator, which Elk Falls is in desperate need of due to other air quality problems. Under this scenario, the mills will still be major creators of dioxin.
Taking the logs out of the water, or making sure they don't soak up so much salt, would seem to be an obvious solution, but it doesn't appeal to the rest of the forest industry. It would require changes in the way they move logs and they don't want to incur the expense. In eastern Canada and the interior of BC, logs are no longer transported down the rivers due to the nasty impact on fish habitat.
Although the river drive has long been a heroic and romantic part of Canadian logging history, the industry changed and thrived. Even in Newfoundland and Labrador, logs are now moved by barge and off-loaded onto dry land sorts.
Coastal mills that continue to make dioxin from hog fuel include Fletcher Challenge Elk Falls, Fletcher Challenge Crofton, Harmac Pacific, Howe Sound P & P, Pacifica Port Alberni, Pacifica Powell River, Western Pulp Port Alice, and Western Pulp Squamish. The first two of these, the Fletcher Challenge mills, release the greatest amounts into the air.
It's time for BC log handlers to modernize and try some innovative changes, such as: more use of barges and cranes, less loss of logs from sloppy handling, speedy delivery, cut-on-demand, and computerized inventories.