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Archive for the ‘Green Chemistry’ Category

John Warner’s Lecture at the 2010 Bioneers Conference on Green Chemistry & Intellectual Ecology

Nature teaches us that no system is truly isolated and positive synergies are often at work. Yet the isolation of the various technological disciplines in our educational and industrial institutions has limited synergy in the human-built world. These walls are starting to break down.

A seminal founder of Green Chemistry, Dr. John Warner explores the opportunities to learn from nature about materials and the very process of innovation and creativity. He co-founded the Warner Babcock Institute for Green Chemistry, and was formerly a professor of Community Health and Sustainability and of Plastics Engineering at the University of Massachusetts-Lowell. Author of over 100 patents, papers and books including Green Chemistry: Theory and Practice, he serves on the board of the Green Chemistry Institute in Washington DC

John Warner | Intellectual Ecology Part 1

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Cloudy with a chance of toxics: How climate change is increasing our vulnerability to chemical pollution by Elizabeth Grossman

December 3, 2009

This guest post is by Elizabeth Grossman, author of Chasing Molecules: Poisonous Products, Human Health, and the Promise of Green Chemistry and High Tech Trash: Digital Devices, Hidden Toxics, and Human Health, and other books. She writes about environmental and science issues for the Washington Post, Salon, Mother Jones, the Nation, Grist, and other publications from Portland, Oregon. One of the book’s jacket quotes is from The great environmental writer and founder of 350.org, Bill McKibben: “There are enough environmental problems that seem insoluble. Elizabeth Grossman has given us this chronicle of a field with a bright future, the green chemistry that will replace the crude methods of the 19th century with the smart ones of the 21st. She tells us how it could happen. We should listen carefully!“

To melting ice caps, rising sea levels, acidifying oceans, and storm surges, add lung diseases and kidney stones to the expected effects of climate change. At a November 19 briefing in Washington, researchers from the Harvard Center for Health and the Global Environment, representatives of the American Medical Association and American Public Health Association detailed the likely negative health effects of global warming. These are conditions, reported Paul Epstein, Associate Director of the Harvard center, to which children, the elderly, and poor are especially vulnerable.

Rising temperatures, ozone and sulfur dioxide levels, along with particulate and other pollutants released by forest fires, will create conditions that are expected to increase rates of hospitalization for respiratory diseases, among them pneumonia, asthma, and chronic lung disease. Increased heat exposure, noted the researchers who’ve described these effects in a letter to President Obama, is also likely to increase the incidence of kidney stones.

But these are just some of the adverse health impacts associated with climate change.

In addition to the effects noted at the November 19 briefing – and those prompted by impacts of drought and altered insect patterns – rising temperatures are already triggering environmental conditions that have less visible but potentially profound health implications.

For traveling with global air and ocean currents are a soup of environmentally persistent synthetic chemicals whose behavior and effects are being exacerbated by climate change. Scientists tracking these chemicals around the globe are discovering that the movement of these long-lasting substances – manufactured materials that have no natural origin – is being accelerated by effects of rising temperatures. Researchers are also finding that global warming is increasing human and wildlife communities’ vulnerability to these chemicals’ biological impacts.

One of the places this is happening most dramatically is in the Arctic. Thanks to patterns of atmospheric circulation, whatever is released into air and oceans in the Northern Hemisphere, eventually moves north. This includes persistent pollutants.

After drifting north over months, years – and even decades – these chemicals typically become lodged in ice, snow, and permafrost. But as temperatures rise, these contaminants are being released as glaciers, polar sea ice, and permafrost melt. At the same time, climate change is prompting earlier Arctic springs, longer summers, and increased precipitation. More rain and snow and greater and faster snowmelt are causing erosion along polar riverbanks, lakes, and coastlines. Consequently, soil-bound contaminants are being washed into nearby water along with whatever pollutants arrive with the precipitation itself.

Further south, extreme storms like Hurricane Katrina can similarly release contaminants previously held in place by soil and send them into adjacent air and water. Some of these chemicals will later move into the atmosphere and back down to Earth again with moisture. Raining toxics sounds a bit extreme, but that’s what it amounts to.

What makes these chemicals’ behavior of even greater concern is that they are finding their way into our food, our bodies, and the innermost workings of living cells.

This is happening because many of these persistent synthetic chemicals are fat-soluble. In the Arctic – and in more temperate latitudes – these chemicals are accumulating in fat cells and thus climbing the food web. Arctic animals, particularly top predators like polar bears, with their large fat stores have among the highest levels recorded of some of these mobile persistent pollutants.

Meanwhile, seasonal climate changes are adding to these animals’ vulnerability. As altered temperature patterns change timing and location of food sources, some animals in polar regions north and south must migrate farther to find food. The lengthened hunting trips increase the animals’ stress levels and their reliance on stored body fat. Because fat cells serve as a reservoir for many contaminants, when fat is broken for energy, the toxics are also released, exposing the animals from within. There is concern that such toxics release is happening in people as well – concern underscored by the fact that a number of these chemicals appear to disrupt hormone activity with results that include adverse impacts on metabolism, including fat production.

There is no quick fix for these problems but it is worth noting that our reliance on fossil fuels has helped make petrochemicals the foundation for the overwhelming majority of our synthetic materials – manufactured substances that go into everything from computers to cosmetics. And petrochemicals have particularly problematic environmental and health impacts. To begin stem this tide, as we begin to shift away from fossil fuels and create new materials – alternatives to those with adverse environmental and health impacts – among the questions we must ask to help ensure new materials’ safety must be: how a substance behaves biologically – its impact on living cells – and how it behaves physically, including its possible contribution to the impacts of climate change.

To access more about Elizabeth Grossman and Chasing Molecules click on the link below.


Chasing Molecules

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Green Chemistry: Theory & Practice

3.1 Alternative feedstocks/starting materials

Currently, 98% of all organic chemicals synthesized in the United Sates are made from petroleum feedstocks. Petroleum refining takes up 15% of the total energy used in the US, and its energy usage is rising because the low quality raw petroleum available now requires more energy for refinement. During conversion to useful organic chemicals, petroleum undergoes oxidation, the addition of oxygen or an equivalent; this oxidation step has historically been one of the most environmentally polluting steps in chemical synthesis. As a result of these consideration, it is important to reduce our use of petroleum-based products by using alternative feedstocks….

The exploration of biological sources of alternative feedstocks need not be limited to agricultural products: agricultural waste or biomass, and non-food-related bioproducts, which are often made up of a variety of lignocellulosic materials, may provide important alternative feedstocks.

Other classes of alternative feedstocks are also emerging, such as light. For example, heavy metals, which are often used in petroleum oxidation processes, are also quite toxic and are carcinogens or cause damage to neurological systems. Recently discovered alternative syntheses replace the heavy metal reagents with the use of visible light to carry out the required chemical transformations.

3.3 Alternative Solvents

An important area of green chemistry investigations has centered around the selection of a medium in which to carry out a synthetic transformation. Because the dominant paradigm of chemical synthesis has been around solution chemistry, the question is often phrased as ‘What solvent should be used?’. This phrasing, of course, begs the question, ‘Should a solvent be used at all?’. Many of the solvents commonly used are some of the volatile organic compounds known to cause smog when released to air. These solvents are listed in the United States’ Clean Air Act as substances to be avoided. Research is being is conducted that pursues chemistry that has previously been done in a solvent and discovers a way to do the same chemistry in various solventless systems….

3.4 Alternative product/target molecule

While a synthesis is often driven by the pursuit of a particular target molecule, it is also commonly the case that what is actually being pursued is the ability to make any chemical that can serve a particular function or have a certain performance criterion. For many years the pharmaceutical industry has been doing research into designing safer chemicals. With pharmaceuticals, the object is to maximize the therapeutic benefits of a molecule while minimizing or eliminating the toxic side-effects. These same principles can be applied to the full range of chemical applications.

In the cases where function is the primary motivation, molecular manipulation that preserves efficacy of function while mitigating toxicity or other hazards is the goal of green chemistry. Through these efforts and other toxicological research, it is often possible to identify the part or parts of a molecule that produce toxic effects. Similarly, through chemical research, we are able to identify those parts of a molecule that are required to give the chemical the desired function – to allow it to serve a specific, desired use.

In designing safer chemicals, one identifies the undesirable, toxic portion of a molecule and lessens or eliminates its toxicity, while maintaining the function of the molecule. In many cases, the overlap of the toxic and functional portions creates a worthy challenge for the synthetic chemist….

3.6 Alternative catalysts

Some of the major advances in chemistry, especially industrial chemistry, over the past generation have been in the area of catalysis. Catalysis has not only advanced the level of efficiency but has also brought about concurrent environmental benefits. Through the use of new catalysts, chemists have found ways of removing the need for large quantities of reagents that would otherwise have been needed to carry out the transformations, and would ultimately have contributed to the waste stream. It is true that various classes of catalysts, such as the heavy metal-based catalysts, have been found to be extremely toxic.

excerpts from pages 22 – 27

Click on the link below for sales and additional information regarding this groundbreaking book.


Green Chemistry: Theory & Practice

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Chasing Molecules by Elizabeth Grossman

Excerpt from the chapter Material Consequences
Pages 160 – 161

Concepts in Green Chemistry

“The fundamental concept of green chemistry,” Collins tells me, can be spelled out in an equation: “Risk equals exposure times hazard [Risk = Hazard X Exposure]. As green chemists, let’s try to understand the hazard and get the hazard out. We have to turn the aircraft carrier around and get the hazard out.” Another aspect of this metaphorical ship is that we’ve relied on our preferred energy source–petroleum–to supply the base for so many of our current synthetics. “If you don’t have the energy problem fixed, it overwhelms everything else.” notes Collins.

“A hundred years ago, the chemical industry was terrible about protecting us from chemicals that kill cells. Now we’re dealing with chemicals that disrupt cellular development, chemicals that interact with DNA and may cause mutations that can lead to cancer. The stakes of not dealing with endocrine disrupters are very high. We need to address endocrine disruptors from inside chemistry.” It all comes back to chemical design, Collins believes.

“The body has a magnificent mechanism for destroying chemicals,” says Collins. And some chemicals need to be persistent. “Drugs must be persistent to work. But when they get into rivers and lakes–what does that mean in the long term?” Yet he points out–alluding to the endocrine-disrupting compounds found in so many personal care products, cosmetics, gadgets, and textiles–persistent compounds are being used to “gloss up the life of adults while messing up the life of kids. There needs to be a mandate of intergenerational responsibility in a way we’ve never seen before.”

“There’s a fracture in the world of research, with research threatening the status quo of corporate culture. Real-time profits are going to be challenged and it’s extremely threatening to certain segments of corporate culture,” says Collins. “How do you respond to a new product when there is a problem? Do you pretend it doesn’t exist? We need to talk about it publicly. These issues really, really matter, and we need to do something about them.”

The morning after the presentation he’s given to the Oregon Environmental Council, I have a conversation with Collins over breakfast. “Capitalism can’t work for sustainability without credible government constraints,” he tells me. “We’ve been obsessed by technical performance and entirely missed anticipating bioaccumulation.”

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Chasing Molecules by Elizabeth Grossman

“I’ve synthesized over a hundred molecules that never existed before,” Warner tells me. By the time he finished graduate school at Princeton in 1988, with a PhD in organic chemistry, Warner had published seventeen scientific papers–many on compounds related to pharmaceuticals, particularly anticancer drugs–a volume of research publication he immodestly but matter-of-factly says is “perhaps unprecedented.”

One day Warner got a call from Polaroid offering him a job in their exploratory research division. So he went to work synthesizing new materials for the company, inventing compounds for photographic and film processes. Describing his industrial chemistry work in an article for the Royal Chemistry Society, Warner wrote: “I synthesized more and more new compounds. I put methyl groups and ethyl groups in places where they had never been. This was my pathway to success.” There was even a series of compounds he invented that, in his honor, became known as “Warner complexes.”

Warner had married in graduate school and while working at Polaroid had three children. His youngest and second son, John–born in 1991–was born with a serious birth defect. It was a liver disease, Warner tells me, caused by the absence of a working billiary system (which creates the secretions necessary for digestion). Despite intensive medical care, surgery, and a liver transplant, John died in 1993 at age two. “You can’t imagine what it was like,” says Warner. “Laying awake at night, I started wondering if there was something I worked with, some chemical that could possibly have caused this birth defect,” Warner recalls. He knows it’s unlikely that this was the case, but contemplating this possibility made him acutely aware of how little attention he and his colleagues devoted to the toxicity or ecological impacts of the materials they were creating….

“I never had a class in toxicology or environmental hazards,” Warner tells me. “I have synthesized over 2,500 compounds! I have never been taught what makes a chemical toxic! I have no idea what makes a chemical an environmental hazard! I have synthesized over 2,500 compounds! I have no idea what makes a chemical toxic!” “We’ve been monkeys typing Shakespeare,” he adds.

“The chemical synthesis toolbox is really full, and 90 percent of what’s in that toolbox is really nasty stuff.” It’s a coincidence and reality of history, Warner tells me, but the petroleum industry has been the primary creator of materials for our society. “Most of our materials’ feedstock is petroleum. As petroleum is running out, things will have to change.” But, he says, it’s an oversimplification to say that using naturally occurring, non petroleum materials will automatically be safe.

Industrial chemistry has relied on the criteria of performance and cost. But safety, Warner adds has not been an equal part of the equation. Green chemistry puts safety as well as material and energy efficiency on a par with performance and cost. This sounds like common sense, but our economic system’s overwhelming focus on performance–combined with the past century’s reliance on what have been inexpensive petroleum-based feedstocks (or base materials)–have created a vast number of high-performing but environmentally inefficient and detrimental materials.

What we need to do, says Warner, is link the design and function of the new materials and new molecular synthesis with an assessment of their hazard and risk. “Historically, we’ve mitigated risk,” explains Warner, “and we’ve done this by trying to limit exposure,” If we eliminate hazard in the first place, the issue of quibbling over exposure limits–where all of our chemical pollutant regulatory energy has been focused–goes away. If you haven’t created and put materials with inherent hazards into introduction and commercial uses, you do not have to decide, for example, if it’s safe to expose high school but not elementary and middle school students to lead dust emanating from artificial turf, or wonder why New York allows its residents to be exposed to higher levels of a potentially carcinogenic agent than does California.

“We’ve taken it as a fait accompli that chemistry must be dangerous. But the cost of using hazardous materials is exponentially more costly,” says Warner. “There is no reason that a molecule must be toxic in order to perform a particular task.” the cost of storing, transporting, treating, and disposing hazardous materials, not to mention the expense of liability, and corporate responsibility for worker health and safety, are among the high costs associated with using hazardous materials. Corporations have seldom been required to take responsibility for hazardous materials they use or produced–apart from product failures–beyond some aspects of the manufacturing stage. The costs of environmental impacts were not considered an explicit cost of doing business; they were what are referred to technically as externalities. As that view has slowly begun to change, with pressure from consumers, unions, government regulators, and the courts, manufacturers are increasingly motivated to find ways to reduce these costs. Green chemists argue that one of the most effective ways to do so is by designing more environmentally benign and efficient products.

“What you do in industrial chemistry,” says Warner, “is make and break bonds–bonds that come together and apart again, that assemble and reassemble, and are reversible–dominate.” This is important, he tells me, because “if we can learn what molecules ‘want’ to do–if we can learn what they do in nature–we should be able to make better, less toxic products.” If we can do that, we won’t be fighting nature or introducing ultimately unwanted, often hazardous, and inefficient elements into the synthetic process.

“…I had a great relationship with Polaroid,” recalls Warner, “But after my son died, I left because I wanted to create the world’s first green chemistry PhD program” –which he did, at the University of Massachusetts–Lowell in 2002… Warner tells me, “Chemistry for nonscientists is all about the environment, but the American Chemical Society that accredits U.S. academic chemistry programs includes no environmental studies in its requirements.”

“One of the astonishing things I learned while talking to green chemistry advocates and chemical engineers–and that helps explain why there has been so little attention to anything like footprint analysis–is that neither toxicology nor ecology has been required as part of a chemist’s academic training” – Elizabeth Grossman

Listen to the discussions of environmental impact and product life and you’ll likely hear the phrases “life cycle analysis,” “cradle-to-cradle,” “cradle-to-grave,” and “cradle-to-gate.” All can be variously and subjectively defined. A life cycle analysis is generally understood to analyze and account for the environmental impacts of a product’s entire manufacturing process, its impacts while in use, and its impacts when a product is no longer useful. Cradle-to-cradle assumes the premise of a closed loop production and product life-cycle loop–in which materials are reclaimed and reused, while cradle-to-grave assumes disposal rather than reuse or recycling for at least some portion of the product when it’s discarded. Cradle-to-gate, meanwhile, has cropped up as a way for companies to measure the environmental footprint of their products but to stop at the factory gate–excluding what happens when the product goes out into the world. The proliferation of terms indicates that assessing environmental impacts is far from a standardized process and is often more of an afterthought than an integral consideration from the beginning of the manufacturing process for synthetic chemicals or any other product.

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