Petrochemicals in Cleaners?

A reader writes The Green Guide:

What is the difference between cleaning products that use petroleum-based ingredients and cleaning products that don't? I was told that Seventh Generation does use petroleum in their products but that some cleaners don't. How does that effect our health? Why would Seventh Generation do that if it is bad for you? Why is it bad for you?

The Green Guide responds:

Ever since the 1940s when scientists discovered petroleum could be broken down and its building blocks combined with other chemicals to create everything from polyester to plumbing pipes, it's become ubiquitous in our homes. And there is no clearer demonstration of this than in household cleaners.

Petrochemicals are cheaper and more effective, manufacturers claim, than their plant-based counterparts, but at the same time, they have detrimental effects on your health. Petrochemicals emit harmful volatile organic compounds (VOCs), which trigger asthma and other respiratory problems, can mimic hormones in your body and can cause liver damage. In extreme cases, petrochemicals can cause cancer. Butyl cellosolve, also referred to as 2-butoxyethanol, is a petroleum-based solvent commonly used in window and spray cleaners that can damage your liver and your red blood cells. Alkylphenol ethoxylates (APEs), petroleum-derived surfactants used in detergents, can mimic the hormone estrogen and have shown up in breast cancer cells. Furthermore, APEs don't biodegrade and end up in waterways where they're absorbed by fish and harm the animals' reproductive systems.

All of the above says nothing of the fact that petroleum is a non-renewable resource that is usually imported from another country. And shipping oil across the globe adds to greenhouse gas emissions, therefore contributing to global warming.

That being said, petroleum ingredients in household cleaners are really hard to avoid, even among environmentally preferable cleaners like Seventh Generation's. But in these cleaners, the use of petrochemicals is a bit different. Whereas conventional cleaner manufacturers will derive an entire ingredient, such as such APEs, from petroleum, companies like Seventh Generation mix a much smaller amount of a petroleum-derived ingredient with another less-harmful vegetable-based (also called "olefin" or "oleo") ingredient to create a new ingredient with fewer health risks and a better environmental profile. For example, instead of using APEs, many natural cleaning products contain alcohol ethoxylates, which are created when vegetable oils are combined with the petrochemical ethylene oxide in a process called ethoxylation. Alcohol ethoxylates are generally safe, but the process of ethoxylation produces a by-product called 1,4-dioxane, an EPA-classified probable carcinogen that is present in very small amounts in the final product. Little is known about the danger levels of 1,4-dioxane exposure, but the National Institute for Occupational Safety and Health considers levels of 500 parts per million (ppm) to be "immediately dangerous to life and health," while many cleaner manufacturers only allow dioxane levels of five parts per million (ppm) in their products. Despite the health risks, alcohol ethoxylates biodegrade unlike APEs, drastically reducing environmental impacts on wildlife, and the process of creating them uses less petroleum and conserves energy. "It takes more energy to convert petroleum into a surfactant than it does to convert plant oil into surfactant," says Martin Wolf, director of product and environmental technology at Seventh Generation.

It may seem strange to use petroleum to avoid having to use petroleum, but in most cases it's necessary in order to get the product to work. "V egetable oils don't clean well," says Wolf, "so we have to modify them." He adds that the best way to modify a vegetable oil to enhance performance is to mix it with sodium hydroxide, or lye soap, a non-petroleum material. Lye soap, however, doesn't dissolve well in hard water, generating soap scum, and users would have to use more of the product to get the desired results. Sodium hydroxide is also very caustic to the skin and respiratory passages, posing a health threat to factory workers.

Product effectiveness and, ironically, resource consumption are also two reasons why the makers of Method, a line of eco-friendly cleaners sold through Target, use a small percentage of petroleum in their products, says Adam Lowry, the company's co-founder.

"In order to understand the environmental profile of a raw material you must consider the entire life cycle of the material. You must understand not only from where it is sourced, but how much energy did it take to extract it, transport it and ethoxylate it," says Lowry. Palm oil, a popular vegetable-based alternative to petroleum, is a prime example, he says. Most palm oil comes from Southeast Asia, and its extraction from the rain forest not only takes massive amounts of petroleum but also destroys endangered orangutan habitats. Additionally, you have to use a good deal more palm oil than petroleum to get an effective ingredient. "It's only under circumstances like this that we'll select a more environmentally responsible petroleum-derived ingredient over an oleo-derived one," he says. (Read more about pressuring companies into using more responsibly extracted palm oil in "Say NO To Palm Oil," www.thegreenguide.com/doc.mhtml?i=int&s=palmoil).

Lowry notes that when companies try to "out naturalize" each other by using ineffective ingredients, they end up doing more harm than good, as in toilet-bowl cleaners, for instance. "There are plenty of great working toilet cleaners out there that kill the environment when you flush, and plenty of green ones that don't work, and so you flush three times as much down the drain," he says. Since the company can't find toilet-cleaner ingredients that are both effective and environmentally friendly, they've held off on developing one.

If you're really intent on avoiding petroleum ingredients, your best bet is to choose completely vegetable-derived castile soaps, which were originally made from olives but have expanded to include a variety of vegetable oils. Instead of being mixed with petroleum ingredients to make them soluble, liquid castile soaps are combined with potassium hydroxide, a relative to sodium hydroxide and thus similar to lye. Because lye soaps don't dissolve well in hard water, you may want to experiment with these and play around with various dilutions.

Do-it-yourself cleaners made from baking soda, hydrogen peroxide and essential oils are reliable, petrochemical-free alternatives as well. Read recipes for DIY cleaners in our Household Cleaning Supplies Product Report, http://www.thegreenguide.com/reports/product.mhtml?id=15.

RESOURCES

Naturally Clean: The Seventh Generation Guide to Safe & Healthy, Non-Toxic Cleaning by Jeffrey Hollender and Geoff Davis (New Society Publishers, 2006, $15.95)

"Rites of Spring (Cleaning)," GG#112, www.thegreenguide.com/doc.mhtml?i=113&s=rites