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Clean and green: The science of killing household germs

By Julie Kirkwood

Chemist Carole LeBlanc does most of her professional work in a laboratory at the University of Massachusetts Lowell, where she tests alternative cleaning products. Her time there largely is spent helping companies like schools and hotels find effective, safe cleaning products that won't harm the environment or the custodial staff.

In the past few years, though, she has been getting more calls like the one from a Methuen woman who wondered if she knew of a safe product that will get tomato stains out of Tupperware.

Since so much of her work translates to household cleaning products, LeBlanc has decided to share some of her expertise with the public. So we recently asked her to visit the cleaning products section of Wild Oats in Andover.

"Things have gotten bad when you have to take a chemist with you shopping," she joked, as she walked to the section.

She paused in front of the household cleaners, a block six shelves tall. There were a few familiar names, such as Tide and 409, but primarily the brands had names with phrases like, "eco" and "planet."

"It would be very unrealistic for me to say everybody should spend half an hour in the cleaning aisle," LeBlanc said. "That's not going to happen."

The key thing to know, LeBlanc said, is that alternative products have gotten much better over the years, so your chances of finding something that works are pretty good.

"I would not sacrifice performance for going green," she said.

That doesn't mean that everything with a green label or an "environmentally friendly" marketing claim is a great product.

"You're just faced with a lot of choice," LeBlanc said.

So the first thing you do is what you do when shopping for anything else: Look for the thing that's on sale, she said.

On this particular morning there was a sale on a Bi-O-Kleen liquid laundry detergent, on the shelf next to regular-priced Tide detergent.

LeBlanc pointed to the label on the Bi-O-Kleen bottle. Though it was smaller than the Tide bottle, both brands said they would wash 32 loads of laundry. The Tide cost $8.99 and the Bi-O-Kleen, on sale, cost $5.69.

"It's actually going to cost less to buy the alternative product," she said.

This is the time to experiment, she said. Though there was a larger bottle of Bi-O-Kleen, LeBlanc said you should buy the smallest amount possible just to test it. If the product doesn't work well at home, don't buy it again.

But what's wrong with Tide, or any of the other traditional products most people buy?

The main problem, LeBlanc said, is we don't know exactly what they're made of.

Most brand-name cleaners don't list their chemicals ingredients on the labels, only generic terms like "surfactants" or "enzymes." Some chemicals typically found in laundry detergents take a long time to break down in the environment, or irritate the skin and may be suspected hormone disrupters or carcinogens.

"A lot of times it's what the label doesn't tell you that's a source of problem," LeBlanc said. "It's not real clear what it does contain."

The government does not require manufacturers to disclose their ingredients and the companies guard the information, saying it's proprietary.

When a product does list ingredients, that's a good start, LeBlanc said. Then, at least, independent third-party chemists can analyze it determine if it lives up to its environmentally friendly claim. You can see this by looking for certification labels on the product or doing research outside the store.

It takes a little more time than just throwing your old brand in the shopping cart, but it's worth it to know you're getting a product that's safe, for the environment and for the person scrubbing the floors and inhaling the fumes, LeBlanc said.

"You're going to assume that the product that someone is allowed to sell you is safe, and that's not true," she said. "That's wrong."

Green your cleaning routine

We asked Dr. Carole LeBlanc, lab director of the Toxics Use Reduction Institute at University of Massachusetts Lowell and an expert on alternative cleaners, to take us shopping for cleaning products and show us how it's done. She chose Wild Oats in Andover.

Here are some of her tips for trying safer cleaning products.

* Watch out for "green wash." Label claims such as "environmentally friendly" or "bio-based" tell you nothing about the safety or the environmental impact of the product.

Cut through the spin by looking for third-party independent certification, such as the Green Label Seal (

You can also check out the validity of environmental claims, such as eco-safe and nontoxic, and of third-party certifiers at the Consumers Union Guide to Environmental Labels (

* Ask what the experts buy. Many government agencies are going green. Often their list of approved green products is available to the public. In Massachusetts, for example, it's at

* Don't automatically disinfect when you clean. Use disinfectants only when the risk of disease is high, such as when cleaning a kitchen surface contaminated by raw meat or cleaning a telephone receiver that has been touched by a sick person.

* Fragrance and color have nothing to do with cleaning performance. Use unscented products whenever possible.

* Pay attention to labels that say the product is safe when "used as directed." It's a clue that it may be dangerous. For example, it may be safe when diluted and used as a cleaner but dangerous in concentrated form in your cupboard.

* Avoid products that contain nonylphenols, octylphenols and alkylphenol ethoxylate. They appear in some liquid laundry detergents and are suspected hormone disrupters that may cause cancer, birth defects and immune problems. Alcohol ethoxylates are a safe alternative.

* Look for labels that divulge all of the product's ingredients. Most leading brands do not divulge their ingredients, saying it is proprietary material, and the government does not require it. That means even professional chemists may not know what's in there. Reward the forthright brands with your business.

* If you're using a product that doesn't list all ingredients, try contacting the manufacturer and asking for a Materials Safety Data Sheet. Some companies, such as Clorox and Procter & Gamble, post these on their Web sites. The data sheets give specific information about the dangers of the product.

* Some products include in their Materials Safety Data Sheet a numerical rating based on the level of hazard, from slight (1) to extreme (4). Avoid any product with a hazard score higher than moderate (2) for bathroom, glass, carpet and general-purpose cleaning. Also, avoid products for which the company has not disclosed this score.

* Avoid cleaners that carry a "danger" or "warning" statement. Danger means the product may be fatal on short exposure and special protective equipment is required. Warning means the product is corrosive or toxic, or that it may be harmful if inhaled or absorbed.

Think before breaking out the big guns

No matter what type of cleaning products you use, there are ways to use them that will reduce your exposure to potentially harmful chemicals and may also make your cleaning routine easier.

It's all about "targeted hygiene," the new catch phrase in household cleaning.

That's shorthand for saving your big guns ߞ; bleach, ammonia, and brand-name disinfectants with cautions on the bottles ߞ; for the places that are most likely to harbor germs that could actually get into your body and could actually make you sick. Everywhere else you use basic soap and water.

"You don't need to try and disinfect your whole home," said Liz Scott, co-director of the Center for Hygiene and Health in Home and Community at Simmons College.

Targeted hygiene has been a popular concept in Europe for quite a while, Scott said.

Americans are finally catching on because of growing concerns about preventing the spread of new diseases, such as bird flu. At the same time, there is growing concern that overuse of antibacterial products is leading to bacterial resistance. Also, some people believe the rise in childhood asthma could be the result of households that are unnaturally sterile.

"It's funny because for a long time there hasn't been a lot of interest and suddenly it's all come to the fore," Scott said. "The reason it has come to the fore is there's so much more awareness of infection transmission in our homes and in our community."

Here are some tips from Scott and the International Scientific Forum on Home Hygiene, for which she is an adviser, for targeted hygiene.

* Beware of the kitchen sponge. Kitchen sponges are warm, wet and may even contain bits of food: paradise for harmful, food-born germs. If you wipe the counters with a used sponge, you're probably spreading more bacteria than you're eliminating. Better to use disposable dish cloths or paper towels.

* Dish towels can also be contaminated. If a dish cloth or towel comes in contact with a potential source of germs, such as raw chicken juice, throw it in the washing machine on a hot water cycle. It should be dried immediately and stored in a dry place until next use. A cloth that has been stored damp may be heavily contaminated and should be thrown away.

* Prioritize surfaces and utensils that touch raw meat or poultry and unwashed fruits and vegetables. Cutting boards, plates, knives and forks must be washed with soap and disinfected, either with antimicrobial products or high temperatures in the dishwasher. For counter tops, wipe up any spills with paper towel and disinfect with a freshly diluted bleach solution or a store-bought disinfectant.

* Mops, scrub brushes, and scouring pads can also harbor germs. Soak them in disinfectant or dispose of them regularly.

* Avoid disinfectants in other parts of the kitchen. If you haven't cooked with raw meats or produce, or if you've already disinfected that area, all you need is soap (regular dish liquid works fine) to clean the counters, stove top, refrigerator handles and sink. Rinse away any dirt residue and dry the surface with a towel.

* Basic cleaners, the kind without added disinfectants or antimicrobial chemicals, are all you need for routine cleaning of floors. The exception is if you're cleaning up vomit or dog droppings, or if a child crawls on your floors. There have been cases of toddlers picking up Salmonella from the floor where it was tracked in by dogs.

* Bathroom cleaning should target the toilet. If somebody in the household has diarrhea or has vomited, use an antimicrobial product on the toilet at least daily.

* Toilet bowls do a good job of ridding themselves of germs through flushing action. However, the microscopic water droplets released by flushing can contaminate the rim, the seat and the flush handle. Use a basic cleaner on these sites, unless somebody is sick.

* Floors and tubs may have some germs on them in the bathroom, but those germs are unlikely to come in contact with people in a way that can cause disease. A simple cleaner is all you need.

* Diaper buckets and humidifiers are also common germ hideouts. Use disinfectants here.

* Laundry is unlikely to spread disease-causing germs. Still, it is important to use either hot water or bleach on any items that may carry germs, such as bathroom towels, washcloths, kitchen towels and underwear.

* Dry laundry immediately after the wash cycle has finished so bacteria and fungi don't have time to grow on wet laundry sitting in the washing machine. This is especially important for clothes washed in cold water with a non-bleach detergent.

* Don't wash dirty underwear in the same load as items that may be used near food, such as tea towels.

* If you frequently use a cold water cycle without bleach, germs may build up within the washing machine and contaminate clothes. To avoid this, run a hot water cycle once a week or any time odors develop.


Hygiene: Reducing germs to a level at which they will not spread disease. Depending on the circumstances, this may be done through cleaning, disinfecting or a combination of both.

Cleaning: The physical process of removing dirt from an object or surface. The soap or detergent does not contain any special ingredients to kill bacteria, viruses, fungi or spores.

Disinfecting: Using a chemical agent capable of destroying germs. It does not necessarily reach all germs that may be hiding under gobs of dirt, but when it reaches them it kills them. Common disinfectants are bleach, ammonia, rubbing alcohol and chemical formulations labeled antimicrobial, antibacterial, antifungal or antiviral.