There’s a lot of marketing and misinformation about safe household cleaning products.

It’s not as simple as looking for recognizable or pronounceable ingredients in your laundry detergent − a common rule when grocery shopping. It takes complex chemical processes to get your clothes clean. We need chemicals to ward off bacteria and degrade organic matter in stains.

“Ideally, we want to live in a place where we have the least amount of exposure to chemicals, but chemicals are part of our lives, what we’re eating, what we’re using to prepare our food,” says Chris Reddy, a senior scientist at the Woods Hole Oceanographic Institution. 

But how do you determine which chemicals are necessary and which aren't? Here’s how to find the best, and safest, detergent for you.

How does laundry detergent work?

In addition to water and a tumbling washer, for a good cleaning, you need surfactants to penetrate the clothing fibers. This is the "soap" of the laundry detergent. Surfactants trap food, dirt, sweat and oil particles from your clothing and carry them out of the laundry, according to Arm & Hammer. 

Many detergents contain cleaning aids like enzymes, which target specific stains like blood, grass, oil or starches. Many also contain fragrances as well as dyes and colorants to make your clothes appear whiter and brighter.

Baking soda is a favorite home remedy for stains, and while it gives your laundry a great boost it won’t effectively clean your clothes on its own. Baking soda can also harm your washing machine if used in excess over time, according to Tide.

What is the safest laundry detergent?

Detergent makers use chemicals they have identified as effective ingredients to clean your clothes, Reddy says. 

It’s a cost-benefit analysis for consumers. Some detergents let you use colder water. Some require less overall product to work. Some are better at removing heavy-duty stains. Some contain optical brighteners to keep your clothes looking sharp. Some are better for sensitive skin. 

Christie Sayes, a professor of environmental science at Baylor University who specializes in toxicology, says she wants her laundry detergent to have certain enzymes and specialty chemicals to attack stains.

“One thing I personally, absolutely do not want in my detergents are colorants or fragrances,” she says. “Often those things are unnecessary and they have known toxicological consequences even at low doses. … It’s not really needed to cleanse.”

Fragrance-free products contain significantly lower amounts of volatile organic compounds (VOCs), which can have hazardous health effects like respiratory system damage, increased cancer risk and developmental and reproductive impacts.

The problem is that only 7% of cleaning products properly disclose their ingredients, the Environmental Working Group found. They may instead use vague terms like “surfactants” and “fragrances” without saying exactly which chemicals.

So where do you look for a safer option? Third-party certifications may be a good place to start. 

EWG is one of several organizations tracking the human and environmental safety implications of consumer products. They use government regulations and data, academic literature, studies and independent toxicity reviews to rate products on an A-F scale. 

“We’re actually asking companies to substantiate those ingredients with testing data, concentration data, in order to back up their claims,” says Samara Geller, EWG’s senior director of cleaning science. “We’re going above and beyond just reading the ingredient list.”

You can also look to the Environmental Protection Agency’s “EPA Safer Choice,” ECOLOGO or Green Seal.  

“It’s the dose that makes the poison. Everything is toxic at a certain level,” Sayes says. “But as far as the individual ingredients go, you can be sure that (certified products are) safer than what the industry standard is.”

Other than fragrances (including synthetic musks) and colorants, there are several ingredients experts told USA TODAY to look out for. The “safest” laundry detergents likely don’t have these or list them lower on the ingredient label, meaning they’re found in smaller amounts:

• Bleach: Can harm skin, eyes and increase risk of asthma. It can also easily react with other cleaners to produce toxic gases
• Quats (usually ends in -onium chloride): Surfactants that may yield toxicity and health impacts in high exposure
• Borates (boric acid, sodium borate, disodium tetraborate): Can be toxic if ingested and long-term exposure could increase risk of several health issues
• Phthalates (often under fragrances): Studies show reproductive and developmental toxicity in animals
• Amine oxides (also found in some oxidant stabilizers): Good at removing grease but can be skin irritants or can vaporize and cause irritation in the nose

How to find the safest laundry detergent

Reading the ingredient label and checking out third-party ratings and certifications is a good first step. If you want to investigate vague language, Geller recommends calling the company to ask what specifically is in their product.

Don’t fall for “non-toxic” or “natural” marketing either. When you see research that indicates that a chemical is toxic, make sure you understand how much of that is in your laundry detergent and how you’re going to be exposed to it. 

For example, preservatives like parabens are harmful when ingested and may irritate the skin if you mishandle your detergent. But they don't often make it through the laundry cycle and end up on your clean clothes, Sayes says. Additionally, a chemical that may cause skin irritation will affect different skin types differently. 

Safe use is most important. Wear personal protective equipment like gloves and a mask when you’re using cleaning products and wash your hands thoroughly if you get laundry detergent on your skin so it doesn’t travel into your bloodstream. Spray laundry pre-treatment close to the clothes and away from your face in a room with an open window or door.

Best laundry detergent for the environment

Some ingredients, like nonylphenols, are known as endocrine disruptors and can harm aquatic life if they make their way out to the ocean. Exposed wildlife may suffer developmental malformations, reproductive issues, cancer or immune and nervous system disturbances, according to the EPA. Galaxolides, an ingredient in synthetic musks, is toxic to aquatic life.

Nonylphenols have been largely phased out of residential use laundry detergents because of this, but they still may be present in industrial detergents used in hospitals, hotels and nursing homes. Galaxolide can be found in many scented laundry detergents.

Most of the water used in our laundry machines is recycled and disinfected. Still, there’s a chance some of these chemicals could seep through wastewater treatment and end up in the environment. One study that examined the efficiency of a group of septic tanks found that, on average, they leached more galaxolide than the EPA’s maximum concentration guidelines. Wastewater treatment facilities, on the other hand, released less than the recommended maximum, the study found.

Environmental exposure could also occur if the laundry detergent tubs with leftover liquid you throw away end up in the landfill, Sayes says.

However, the plastic pollution, water and energy needed to do your laundry may make a bigger impact. The average home washing machine uses 41 gallons of water per load, according to the National Park Service.

“I do a lot of laundry in my household, I never look at the label,” Reddy says.

Big picture? Excess carbon dioxide and fossil fuel emissions are more detrimental to the environment than laundry detergent, Reddy says. If you’re looking to lower your carbon footprint, he recommends using less electricity, less heat and driving less – or driving electric. 

Best eco-friendly laundry detergents:Tested by our Reviewed team

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