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A New Kind of Clean

Seventh Generation seeks out environmentally friendly detergent ingredients

by Michael McCoy
March 19, 2007 | A version of this story appeared in Volume 85, Issue 12

Cleaning Plant
Credit: istockphoto
Chicory is the source of a dispersant soon to be added to laundry detergent.
Credit: istockphoto
Chicory is the source of a dispersant soon to be added to laundry detergent.

WAITING IN THE LOBBY of the posh Boca Raton Resort & Club, Martin Wolf does not come off as a typical guest. There's an air of the scientist about him, and his pale skin suggests he hasn't been spending time on the beach.

Indeed, Wolf is in Florida not to relax but to attend the Soap & Detergent Association's annual meeting. His mission is to scout out innovative ingredients for detergents and other cleaners marketed by his company, the Vermont-based household products maker Seventh Generation.

Formed in 1988 by entrepreneur Jeffrey Hollender, Seventh Generation strives to sell products that are nontoxic, phosphate-free, biodegradable, and made from renewable ingredients. Its name is inspired by an Iroquois belief that "in our every deliberation, we must consider the impact of our decisions on the next seven generations."

An M.A. chemist, Wolf joined Seventh Generation in 2002 as director of product and environmental technologies after a stint as an environmental consultant to a number of organizations. He had previously worked for Ciba-Geigy, analyzing the impact of pesticides on the environment, and for Thermo-Electron, researching instruments that detect environmental carcinogens.

As a scientist, Wolf tries to be rational about the environmental issues surrounding household product ingredients. He says he searches for plant-derived surfactants not because they are less toxic than chemically identical synthetics—the two are no different—but because their raw materials are renewable. Such surfactants provide a secondary greenhouse gas benefit, he adds, because they require less energy to manufacture than synthetics do.

That benefit doesn't come for free. "We are using materials that are not as readily available, and so they cost more," Wolf acknowledges. The company enjoys neither the purchasing power nor the distribution strength of Procter & Gamble and other big "soapers."

Credit: Michael McCoy/C&EN
Credit: Michael McCoy/C&EN

Even so, Wolf and Hollender want to price their products to keep Seventh Generation's sales growing at a double-digit pace. And Seventh Generation does in fact manage to keep the wholesale price of most of its products within 10% of that of its bigger competitors, Wolf says.

Seventh Generation also wants its products to work well. "People pay a premium for our products, and they expect a product that performs in a premium manner," Wolf says. Earlier generations of environmentally friendly products sacrificed performance, he contends. As a result, he adds, these products ended up alienating the ecoconscious consumers they were meant to serve.

Seventh Generation appears to be avoiding this pitfall. In a January 2007 Consumer Reports survey of laundry detergents, the company's Free & Clear liquid came in 13th in a field of 22 contenders. In March 2005, the magazine rated Seventh Generation's powdered automatic dishwasher detergent ninth out of 20 products. It beat out well-known brands such as P&G's Cascade Complete gel and Reckitt Benckiser's Electrasol powder.

Nowhere is the balance between performance, environmental acceptability, and price harder to achieve than in dishwasher detergents. Consumers expect their machines to get food-encrusted dishes clean and spot-free with nothing but water pressure and a small amount of detergent powder or gel.

Developers of big-name brands like Cascade and Electrasol turn to phosphorus-containing compounds to sequester metals and thereby keep food particles from redepositing. They depend on chlorine-containing bleaches such as sodium hypochlorite or cyanuric chloride to remove tomato sauce and other food stains.

As a chemist, Wolf admires the efficacy of these ingredients. But "they are also the two ingredients we feel shouldn't be in these products because of their environmental impact," he says. "We take out two of the most effective ingredients and are left with a tremendous challenge."

In place of phosphates, Seventh Generation uses citric acid, which is effective but costs almost twice as much. Instead of chlorinated bleaches, the firm leans on enzymes and sodium percarbonate.

In 2001, with those substitutions, Seventh Generation launched what it considered an environmentally acceptable dishwasher detergent under the Free & Clear name. Still, Wolf knew the company was compromising. For one thing, its main surfactant was synthetic. Moreover, Wolf couldn't find a way around using sodium polyacrylate, an able dispersant and antispotting agent that is both synthetic and not biodegradable.

In 2004, Seventh Generation solved the surfactant problem with the help of the specialty chemical company Clariant. As Wolf explains, the alcohols used to make surfactants can be derived from vegetable oil—typically coconut and palm oils—or petrochemicals. But vegetable oil alcohols are mostly 12 carbons long and tend to foam, anathema in automatic dishwashers. Instead, dishwasher detergent manufacturers use synthetic alcohols that are six to eight carbons long and generate little foam.

Mark N. Rhines, a North American business director in Clariant's functional chemicals division, says Seventh Generation's foaming dilemma came to his firm's attention a few years ago.

Clariant researchers in Europe had been working with vegetable-oil-based surfactants at the behest of environmentally conscious customers in the cosmetics and crop protection industries. The company transferred some of this know-how to its laboratories in Charlotte, N.C., where chemists came up with derivatives of the long-chain alcohols that generated much less foam than the originals.

They created a dozen or so candidates that seemed to work in dishwashers, narrowed the slate down to a few choices, and presented them to Seventh Generation. Wolf's team conducted its own tests, picked its favorite, and, satisfied, launched a reformulated dishwasher powder in 2004. A new gel based on the surfactant is scheduled to hit the shelves this year.

Finding a replacement for polyacrylate is proving more difficult, Wolf acknowledges. The company came close to adopting a polyaspartic acid dispersing agent manufactured by Lanxess. Although still a synthetic chemical, the product mimics natural aspartates and is biodegradable. However, efficacy tests conducted in advance of the relaunch were unsatisfactory.

More recently, Seventh Generation has been working with an unlikely product: a chicory-derived dispersant supplied by the St. Louis-based chemical company Solutia.

Solutia's Dequest business supplies organophosphonates as chelating and antiscaling agents for industrial water treatment and detergents. They are effective products but contain phosphorus and aren't readily biodegradable.

About five years ago, while on the hunt for next-generation chelants and antiscalants, Mark Eyers, commercial development manager for Solutia Europe, made contact with Cosun, a Dutch food ingredients company. Among its activities, Cosun extracts inulin, a naturally occurring oligosaccharide, from chicory root for sale as a dietary fiber and sugar replacer. The company was branching out into inulin derivatives for industrial applications and recognized Solutia as a partner with chemistry expertise.

The result of their efforts is the Dequest PB line of carboxymethylinulins, which were recognized last year by the Environmental Protection Agency's new chemicals pollution prevention program. Solutia says the products have good antiscaling, metal sequestration, and dispersion properties, yet they are low in toxicity and are biodegradable. One successful application, Eyers notes, is scale control in the recovery of oil from old, essentially spent wells.

In his effort to push the inulin products into the detergents market, Eyers reached out to several alternative cleaning product firms in Europe and the U.S. Early in 2006, Solutia and Seventh Generation started testing carboxymethylinulin in laundry detergent powder to sequester metals and prevent soil redeposition. The work has been encouraging, and Wolf anticipates incorporating the ingredient in his company's laundry powder later this year.

Seventh Generation and Solutia are also collaborating on a dishwashing powder that uses the chicory derivative in place of polyacrylate. The new formula does a good job of stopping film formation on dishes, Wolf and Eyers agree, and the companies are trying to improve its spot-prevention performance.

But for every reformulation success, other problems have yet to be solved. For example, Wolf is well aware that suppliers of vegetable-oil-based detergent alcohols frequently modify them with ethylene oxide to improve their solubility.

Seventh Generation's Free & Clear spray cleaner contains alkylpolyglucoside, an all-plant-derived surfactant that employs glucose instead of ethylene oxide as the water-loving appendage that makes the product soluble. But such APGs aren't very effective in laundry detergents and other high-surfactant formulas, Wolf points out. "We want to find an alternative to ethoxylation," he says, "but we also want to provide a product that works well."

EVEN PLANT-BASED ingredients aren't free of environmental issues. Wolf has been reading reports about the clear-cutting of rain forests in Indonesia and Malaysia to make room for palm tree plantations. "It's a real issue," he says, "and a major initiative for us this year is to work with surfactant makers to examine the chain of commerce and identify oil sources that are sustainable."

Encouragingly for Wolf, ingredient suppliers are starting to take his concerns to heart. Clariant's Rhines, for example, says his discussions with Wolf have "caused me personally to think about issues I wouldn't have considered." During a meeting at the detergents conference in Florida, Rhines and other Clariant executives talked with Wolf about assessing the environmental impact of plant-based raw materials.

Indeed, as its annual sales approach $100 million, Seventh Generation is starting to enjoy a certain clout that Wolf wants to harness to push the entire household products business toward sustainability.

He tells of searching, back in 2001, for an ethoxylated alcohol with less than 5 ppm of 1,4-dioxane, a contaminant that can form in ethoxylation reactions. Requests to his usual suppliers went unheeded, and he had to scour the market for a company willing to guarantee the lower level.

"Two months later, a supplier called to ask why we weren't buying from them anymore," he recalls. "They came back and said they were willing to guarantee the 5 ppm. A year later, a third supplier said it would."

His company's higher profile is also aiding Wolf at the Soap & Detergent Association conference. He had no appointments with potential suppliers when he first attended five years ago, and few people he met had even heard of Seventh Generation. "This year," Wolf says, "virtually every hour of every day is booked." He expects to enjoy three nice dinners in the process, but he isn't going to make it to the beach.


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