BERKELEY, California – Like many new mothers in this environmentally friendly city, Keri Hayes, a freelance reporter, diapers her 5-month-old daughter in cloth and biodegradable disposable diapers.

But she was dismayed to learn from her cloth diaper service that the biodegradable disposable diapers she purchases from Whole Foods, a grocery chain that specializes in organic foods and environmentally conscious products, aren't much better for the environment or the health of her baby than the Huggies and Pampers piled up in landfills.

"These diapers all contain super-absorbent gelling materials," or AGM, said the latest newsletter from cloth diaper service Tiny Tots. "AGM is linked to an increase in childhood asthma and a decrease in sperm count among boys. Environmentally, these diapers require as much water, energy and fuel to produce as any other single-use diaper. The bottom line is they offer no environmental or health benefits."

Diapering is arguably the most important decision parents could make for the environment and their young children, who are in diapers around the clock for upward of two years. However, no studies indicate that the absorbent substance used in disposables harms babies. Overall, there is little guidance in the contradictory studies and misinformation put out by the diaper industry.

"There is no answer," said Chaz Miller, director of state programs for the National Solid Wastes Management Association. No one can say definitively whether cloth or disposable diapers are better for the environment.

These are the facts: The average baby goes through 5,000 diapers before being potty-trained. Because 95 percent of these diaper changes are disposable diapers, most of them end up in landfills, said John A. Shiffert, executive director of the National Association of Diaper Services.

Diapers made up 3.4 million tons of waste, or 2.1 percent of U.S. garbage, in landfills in 1998 – the last year this information was collected, according to the Environmental Protection Agency. Diapers in landfills in underdeveloped countries are especially problematic because they often aren't properly disposed, and excrement leaks into the local water supply.

New biodegradable brands such as Seventh Generation, Nature Boy & Girl and TenderCare Plus offer only slightly better options. Nature Boy & Girl diapers are made of cornstarch instead of plastic. Neither TenderCare Plus nor Seventh Generation diapers are bleached in chlorine, a process used by the leading disposable-diaper companies that emits toxins into the air and water.

And contrary to popular belief, no diaper – not even biodegradable ones – can break down in an airtight landfill.

"A landfill is not a composting facility," the California Integrated Waste Management Board says on its website. "Nothing degrades well in a landfill."

As if that weren't enough to keep parents awake at night, cloth diaper services and some researchers bombard the public with news articles on the harmful chemicals in disposable diapers. While it is true that the waste water from washing cloth diapers is benign compared with the sludge of dioxins, solvents and heavy metals in waste water from manufacturing disposable diapers, there is no evidence that sufficient traces of the chemicals remain on the diapers to harm babies. As for the primary feature that gives disposable diapers their appeal – their ability to absorb a large volume of liquid – no studies indicate that sodium polyacrylate, the gel-like absorbent substance used in disposables, harms babies wearing the diapers.

Sodium polyacrylate was removed from tampons in 1985 because of its link to toxic shock syndrome, a bacteria-caused illness. But no such connection has been proven for outerwear, including diapers, incontinence products and feminine napkins, which all contain the super-absorbent gel, said Celeste Kuta, an environmental scientist with Procter & Gamble, the leading seller of disposable diapers in the United States.

The one study that does give cloth diapers a leg up in health benefits for baby boys appeared in the October 2000 issue of the Disease in Childhood medical journal. In that article, German researchers found that the scrotal skin temperatures of baby boys were significantly higher when they wore disposable diapers than when they wore cloth. While the scientists called for more research, their article suggested that prolonged use of disposable diapers as infants was an "important factor" contributing to the decline of sperm production among adult males. Proctor & Gamble conducted its own study and also found that scrotal skin temperatures increased for boys in disposable diapers, although not to the degree that the German scientists showed, Kuta said.

Because biodegradable diapers are fairly new – most of the brands are no more than a few years old – no studies have compared their health benefits to nondegradable disposable diapers. But one thing's for sure: There are volumes of studies comparing the environmental impact of cloth versus disposable diapers. The conclusion? It depends on who is asked.

Both Procter & Gamble and the cloth diaper industry took a keen interest in the topic in 1990, the year marking the 20th anniversary of Earth Day. Worried about the environmental impact of soiled diapers in landfills and tree logging to make disposable diapers, 24 states proposed taxing disposables to limit their use. But Procter & Gamble killed those initiatives with hundreds of millions of dollars of lobbying and advertising to consumers, who were already sold on the convenience of disposable diapers, according to a historical timeline by Mothering magazine. The diaper-producing behemoth also released the first in a series of studies to show that cloth diaper services use up another resource: water.

Manufacturers need water to grow the cotton to make cloth diapers. Diaper services need water to launder the diapers. And parents may need even more laundry water if cloth diapers leak, Procter & Gamble's Kuta said.

"It's amazing to see how different (disposable) diapers are now," Kuta said. "They keep getting better at not leaking. If they don't leak on clothing and bed linens, then you don't end up doing an extra load of laundry, which has an environmental impact."

The cloth-diaper camp responded with its own round of studies showing that not only do disposable diapers require more water in manufacturing, but also more trees, energy and fuel. So-called life-cycle analysis, a science that studies the whole environmental impact of a product from acquiring its raw materials to manufacturing it, shipping it to a store, transporting it home and finally to a landfill, is anything but perfect. Often, scientists are comparing apples to oranges: Is a product that uses more water better than a product that takes up landfill space?

The studies are filled with assumptions such as whether the large trucks carrying Procter & Gamble products on an interstate highway are any better or worse for the environment than the fleet of cloth-diaper delivery vans traveling on a congested city street. Also, the studies do not include "second-generation impacts," such as the energy required to fire the bricks to build the kilns used to manufacture a raw material.

"When you deal with life-cycle analysis, there are a lot of factors," NSWMA's Miller said. "You can pick and choose the factors that you want to use. You can purposely or completely by chance make assumptions that will tilt the study one way or another."

On the face of it, cloth diapers appear to be the best way to avoid additional waste dump in landfills. But laundering cloth diapers does appear to suck up a lot of water, which could present a problem in drought-afflicted areas.

"There are downsides to both," Berkeley's Hayes said. "It's a tossup of which is worst: wasting our water supply or filling up our landfills."

Meanwhile, Hayes said she continues to put her daughter, Ella, in a cloth diaper during the day and a biodegradable disposable for outings and at night.

"When she's old enough to express what she likes, I'll get a better idea," Hayes said.

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