“I love the idea of ‘green’ products. Shampoo bars, laundry sheets, reusable paper towels. Which ones actually make a difference?”

— Aviva Loeb, Washington Post digital designer

Here’s the thing about sustainable shopping: There are very few things you can purchase that are actively beneficial for the climate. Unless you’re buying a tree that will suck carbon from the air, most products require land, water and fossil fuels to produce and use. New stuff — clothes, appliances, bath products, toys, etc. — inherently comes at some environmental cost.

Still, we all need new stuff sometimes; even I have had to replace the pair of yoga pants I’ve lived in since the start of the pandemic. By choosing products that are made sustainably, from companies that have demonstrated a commitment to minimize their environmental impact, experts say it is possible to make a difference.

But choosing wisely “really requires the consumer to do their homework,” said Alexis Bateman, director of the Sustainable Supply Chains program at Massachusetts Institute of Technology. There is little government oversight of company claims about environmental impact. Though manufacturers can get their products labeled “eco-friendly” through a huge range of certification programs, “it’s kind of like the Wild West,” Bateman said. There’s no independent validation of these certifications.

To determine whether a product is truly “green,” you’ll have to look deeper than its earth-toned packaging.

Start by researching what it takes to make your product. You may be surprised to find that most clothing contains plastic, which is a petroleum product. It requires 32,000 gallons of water to produce the steel for an average passenger car. That super soft toilet paper you prefer is made entirely from virgin boreal forests — one of the world’s most important carbon sinks. About one-fifth of planet-warming greenhouse gas emissions come from manufacturing, according to the United Nations Intergovernmental Panel on Climate Change.

To find greener options, Bateman said, look for products made from post-consumer reclaimed material. If your toilet paper roll is made entirely with paper that’s already been used at least once, you’ll know you’re not putting additional pressure on forests by purchasing it. Recycling metal for cars and appliances generally uses less carbon than producing new raw materials. Buying products made from recycled material also demonstrates support for what Bateman calls “the circular economy,” in which waste is turned into an ingredient for something new.

But be careful to distinguish between products that have been recycled and those that are recyclable, Bateman cautioned. A product made from reclaimed material is taking trash out of the waste stream. A product that could theoretically be reused is just a promise — one that is usually unfulfilled. About three-quarters of all plastic and a quarter of all paper waste produced in the United States ends up in a landfill, even though all of it is technically recyclable.

Next, consider what it takes to pack and deliver the product to your store — or your door. Does it need to be transported a long distance (shipping accounts for about 3 percent of global greenhouse gas emissions)? Does it come wrapped in a lot of wasteful packaging? As a general rule, Bateman said, purchasing food and other items that are made locally generates less carbon emission, because these products don’t need to be transported long distances or stored and repackaged at a retailer. Things such as shampoo bars and toothpaste tablets, which minimize shipping weight and packaging needs by removing water from the products, are also worth looking into. Paper packaging is usually preferable to plastic, because it is more likely to be recycled, Bateman said. Even better: Look for products packaged in post-consumer recycled material.

The last thing to think about is the environmental impact of using the product. If you buy shampoo bars, but need to use 10 times as much water to get the suds out of your hair, you may end up canceling out the benefits of reduced packaging and shipping weight. Still, reusable products — cloth napkins instead of paper, aluminum water bottles instead of plastic — are almost always preferable to ones you use once and throw away.

Making energy-efficient purchases is one of the more meaningful ways you can cut your personal carbon footprint. Electricity and heat production account for about a quarter of global greenhouse gas emissions, and most electricity produced in the United States still comes from fossil fuels.

Here, consumers have some help in evaluating their options. Energy- and water-efficient appliances are among the few products that are well regulated by the federal government. An Energy Star certification from the Department of Energy and Environmental Protection Agency shows that the products meet certain standards for efficiency. The EPA will pull products off store shelves to test them.

Some companies have committed to offsetting the emissions associated with making their products, but these pledges can’t always be taken at face value. As I’ve reported before, carbon offsets don’t necessarily cancel out emissions from somewhere else.

It’s a lot to keep in mind when you’re standing in the aisle at the pharmacy or grocery store, Bateman acknowledged. Even companies struggle to assess carbon emissions that come from the whole life cycle of their products, she said. Modern supply chains are long and complicated; retailers don’t necessarily know everything about their manufacturers, who don’t necessarily know everything about the sources of their raw materials. In 2012, the British grocery chain Tesco gave up on a plan to put carbon labels on everything it sold after realizing it would take several months to assess the footprint of each item.

“There’s a pretty long history behind different retailers attempting to drive their suppliers to label their products,” Bateman said. But when suppliers realize that carbon footprint evaluations might not be very favorable, “no one wants to do it.”

In many situations, the “greenest” product you can buy is … nothing. Unless your purchase represents a significant upgrade from what you already own — say, swapping out your old gas-guzzling car for an electric vehicle — you are better off trying to refurbish or repurpose existing items than acquiring more stuff. Instead of buying paper towels, tear up old T-shirts to use as rags. Give your family’s discarded books and toys to younger children in your neighborhood. Build your own “circular economy” in your community and your home.

Ultimately, the products we choose to purchase account for a relatively small fraction of global greenhouse gas emissions. Many emissions reductions will need to come from larger scale policy decisions such as decarbonizing the electric grid. For those who can’t afford to make purchases based solely on their environmental impact, advocating for systemic change is just as important.

But I also think about one of the last events I attended before the coronavirus shutdown, a clothing swap at a friend’s home. We ate snacks, listened to music, played with her dog and whenever someone tried on a new outfit, they were greeted with a chorus of affirmation and applause. It was a whole lot more enjoyable than trying on clothes in the fluorescent-lit chill of a department store changing room, and it brought me joy to think about my old clothes finding new life in someone else’s closet. I can’t calculate how big a difference it made, but I think it was at least a dent.

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