Household products can really pollute the air Everyday products like household cleaners emit a bouquet of chemicals that contribute vapours into the air. A spritz of cleanser or spray of some disinfectant will have a small effect. Frequent use of these products by millions of people, however, can really pollute the air. Families wanting to reduce their impact on air pollution might need to do more than trade in a gas-guzzling car, a new study reports. It found that simple household items also are dirtying urban air. One example: those nicely scented air fresheners. Paints, cleaning supplies and personal care products (think deodorants and hair sprays) are among common products that send a host of chemicals into the air. These air pollutants — some of them sweet smelling — now contribute as much to lung-irritating ozone and to tiny airborne particulates as does the burning of gasoline or diesel fuel. It might not seem that way, but the finding is a mark of success, says Brian McDonald. He is a chemist at the Cooperative Institute for Research in Environmental Sciences in Boulder, US. He also was an author of the new study. Steps to clean up car exhaust over the past few decades have had a huge effect, says McDonald. As a result, he notes, in cities “the sources of air pollution are now becoming more diverse.” Spyros Pandis works at Carnegie Mellon University in Pittsburgh, US. He’s a chemical engineer who did not take part in the study. “When you have a big mountain in front of you,” he explains, “it's difficult to know what lies behind it.” Now that big sources (such as traffic emissions) are falling, other sources become more visible. The new study focused on a class of pollutants known as volatile organic compounds. Most are derived from petroleum or other fossil fuels. These VOCs are hundreds of diverse chemicals that easily evaporate. These gases then may linger in the air. Some VOCs can be harmful when directly inhaled. Bleach and paint fumes make people lightheaded, for example. But beyond their immediate effects, VOCs also can react in the air with other chemicals. (These include oxygen and nitrogen oxides, largely from vehicle exhaust.) Those reactions can create ozone as well as/fine particulates/. High levels of fine particulate, tiny dustlike motes, can make it hard to breathe. They also can help foster chronic lung problems, diabetes and heart disease. (And while ozone high in the atmosphere helps shield earth from the sun’s harmful ultraviolet rays, at ground level it mixes with fine particulates to brew up breath-choking smog.) For six weeks, the researchers collected air samples in Pasadena, California, US. This was at a site in the well-known smoggy Los Angeles valley. They also studied indoor air measurements made by other scientists. The team traced the VOCs in these air samples to their original sources. To do this, they used databases showing the particular VOCs released by different household products. Those household products had an outsized effect on air pollution, the team now reports. By weight, people use about 15 times more gasoline and diesel compared with VOC-emitting goods, such as soaps, shampoos, deodorants, air fresheners, glues and cleaning sprays. Yet those household products were responsible for 38 percent of the VOC emissions, the researchers found. That amount is 6 percentage points higher than the share due to gasoline and diesel use. The VOCs from household products also contributed as much as the fuels did to the production of ozone and fine particulates. So the next time you want to reach for that air freshener or hair spray, think again. ------------------------------------------------------------------------ BOX VOC-emitting consumer products Shampoo Hairspray Deodorant Perfume Air fresheners Cleaning sprays Laundry detergent Disinfectant wipes Hand sanitizer Glue Paint END OF ------------------------------------------------------------------------ Power Words bleach: A dilute form of the liquid, sodium hypochlorite, that is used around the home to lighten and brighten fabrics, to remove stains or to kill germs. chronic: A condition, such as an illness (or its symptoms, including pain), that lasts for a long time. diesel fuel: Heavier and oilier than gasoline, this is another type of fuel made from crude oil. It’s used to power many engines — not only in cars and trucks but also to power some industrial motors — that don’t rely on spark plugs to ignite the fuel. exhaust: (in engineering) The gases and fine particles emitted — often at high speed and/or pressure — by combustion (burning) or by the heating of air. Exhaust gases are usually a form of waste. fossil fuel: Any fuel — such as coal, petroleum (crude oil) or natural gas — that has developed within the Earth over millions of years from the decayed remains of bacteria, plants or animals. nitrogen oxides: Pollutants made up of nitrogen and oxygen that form when fossil fuels are burned. The scientific symbol for these chemicals is NOx (pronounced “knocks”). The principle ones are nitric oxide (NO) and nitrous oxide (NO_2 ). organic: (in chemistry) An adjective that indicates something is carbon-containing; a term that relates to the chemicals that make up living organisms. oxygen: A gas that makes up about 21 percent of Earth's atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism). ozone: A colorless gas that forms high in the atmosphere and at ground level. When it forms at Earth’s surface, ozone is a pollutant that irritates eyes and lungs. It is also a major ingredient of smog. particulate: A tiny bit of something. A term used by pollution scientists to refer to extremely tiny solid particles and liquid droplets in air that can be inhaled into the lungs. So-called coarse particulates are those with a diameter that is 10 micrometers or smaller. Fine particulates have a diameter no bigger than 2.5 micrometers (or 2,500 nanometers). Ultra-fine particulates tend to have a diameter of 0.1 micrometer (100 nanometers) or less. The smaller the particulate, the more easily it can be inhaled deeply into the lungs. Ultra-fine particulates may be small enough to pass through cell walls and into the blood, where they can then move throughout the body. petroleum: A thick flammable liquid mixture of hydrocarbons. Petroleum is a fossil fuel mainly found beneath the Earth’s surface. It is the source of the chemicals used to make gasoline, lubricating oils, plastics and many other products. pollutant: A substance that taints something — such as the air, water, our bodies or products. Some pollutants are chemicals, such as pesticides. Others may be radiation, including excess heat or light. Even weeds and other invasive species can be considered a type of biological pollution. smog: A kind of pollution that develops when chemicals react in the air. The word comes from a blend of “smoke” and “fog,” and was coined to describe pollution from burning fossil fuels on cold, damp days. Another kind of smog, which usually looks brown, develops when pollutants from cars react with sunlight in the atmosphere on hot days. From Science News for Students