The Green Lantern

Smells Like Green Spirit

Are air fresheners bad for the environment?

Is air freshener earth-friendly?

I like having air fresheners around the house, but the other day it occurred to me that I don’t know what exactly they’re puffing into my living room. Am I despoiling the planet by freshening my air?

Air fresheners seem to occupy a special place, along with Hummers and offshore drilling, in the environmentalist’s doghouse. Maybe it’s the synthetic smell or the phony alpine meadow on the packaging. But the Lantern suspects people have never gotten over the chlorofluorocarbon crisis of the 1970s and ‘80s.

Americans fell for the flowery goodness of canned aerosol air fresheners in 1956, when the S.C. Johnson Co. first released Glade. (It was a big year for aerosols. The company rolled out Raid insecticide around the same time.) The magic ingredients in the aerosols were chlorofluorocarbons, or CFCs. These propellants are nontoxic, unlikely to explode, and don’t react with other ingredients. Then two chemists published a paper in 1974 showing that CFCs could break up ozone molecules, which protect us from ultraviolet light. In 1985, scientists confirmed the breakdown of ozone in the stratosphere, and over the next seven years most countries agreed to phase the chemical out. (Check out the Green Lantern’s full update on the ozone layer.)

While manufacturers quickly developed CFC-free aerosols, the public soured on spray cans. Companies have since developed alternative ways to perfume your living room, most of which rely on some form of automated delivery system. The most common use heat to evaporate the fragrance or fans to disperse it.

Does the new generation deserve a clean bill of environmental health? The elimination of CFCs is, without question, a major step forward. But it’s very hard to say how green today’s air fresheners really are. While some manufacturers have published company-wide resource consumption data, none have broken down the environmental impact of their factories and distribution systems by individual product, so the Lantern can’t tell you how many carbon dioxide equivalents are produced during the lifetime of a country-spice refill pack. We do know that, over the course of the year, an ordinary plug-in air freshener will use about 18.4 kWh of electricity, about half a gallon of oil’s worth. * (The kinds with night lights can use up to twice that much.) You’d need to run between 30 and 50 plug-ins to match the energy consumed by your refrigerator.

You’ll have to decide for yourself whether having your house smell like a country meadow merits those emissions levels. But the current assault on air fresheners has less to do with carbon dioxide than toxic chemicals. In particular, public health and environmental advocates want to know what sorts of toxins might be lurking inside the “fragrance” that’s listed on the product packaging.

The problem is, manufacturers don’t have to reveal exactly what’s in their fragrance recipes, and some of them don’t even know the ingredients themselves. Many purchase their scents from a half-dozen or so major fragrance houses worldwide. The fragrance houses often make their customers promise not to chemically analyze their super-secret blends, or at least not to disclose the recipe.

That hasn’t stopped independent researchers from running their own tests. Scientists have been studying “fragrance” for the last decade and have found enough to worry consumers. Gina Solomon, a physician with the Natural Resources Defense Council, recently discovered distressing levels of phthalates in some major brands. (Phthalates are hormone-disrupting chemicals that may cause birth defects.) In response to Solomon’s study, Walgreen’s pulled its brand of air fresheners from the shelves, and S.C. Johnson volunteered to ditch the ingredients in question.

Air fresheners may also contain volatile organic compounds, or VOCs. Some members of this much-hyped but little-understood class of chemicals are hazardous to both environmental and human health. In particular, Anne Steinemann of the University of Washington showed that a few of the leading air-freshener brands contain a probable human carcinogen and federally-designated “hazardous air pollutant” called acetaldehyde.

The industry insists there’s no evidence that these chemicals are harmful at the levels produced by air fresheners. That’s sort of true, since we don’t have very much evidence at all about VOCs and their effects on health. But there are reasons to be concerned. The federal and state governments are worried about VOCs polluting the ground water, and the EPA recommends minimizing your exposure to them.

For the most part, however, the EPA doesn’t concern itself with the levels of acetaldehyde in air fresheners, because they have limited their jurisdiction to outside air. That’s somewhat unfortunate, since VOC concentrations tend to be 10 times higher indoors than out, due to products like air fresheners, paint, and cleaning supplies.

Right now, no one really knows what long-term exposure levels of acetaldehyde or other VOCs are safe. Nor do we know what kind of dose we’re getting from a quick spritz of alpine fresh.

If you’re looking to minimize VOC exposure but just can’t resist the smell of French vanilla, your options are limited. Products marketed as being all-natural or organic may emit the same types of VOCs as other products, according to Steinemann. And your beloved patchouli incense is no better. The problem isn’t the delivery device; it’s the chemical used in the fragrance itself—and most incense and scented candles contain the same VOCs as those scary aerosol cans.

So what’s a conscientious consumer with a rank apartment to do? Here’s one time-honored solution: Open a window. Unfortunately, the air outside the Lantern’s New York apartment smells more like garbage than a “gentle brook when lavender, Casablanca lily and fresh water meet.” He may have to get medieval on an orange instead.

Is there an environmental quandary that’s been keeping you up at night? Send it to, and check this space every Tuesday.

Correction, Sept. 14, 2010: The original article mistakenly stated that a barrel of oil produces 18.4 kWh of energy. (Return to the corrected sentence.)

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