Bags made from organic cotton, grown without pesticides, fare even worse environmentally. Because organic cotton yields are 30 percent less than conventional cotton, they need 30 percent more water and land to produce the same amount as conventional cotton. Organic cotton bags need to be used 20,000 times to equal the environmental impact of plastic bags. Today, another critical factor to consider is that cotton and other reusable shopping bags can carry bacteria and transfer it from home to grocery carts and checkouts and back again. One study of reusable bags discovered that they were rarely washed and as a result, bacteria were found in almost all the bags studied, with 12 percent containing E. coli. While most reusable bags are made of polypropylene, upon which COVID-19 has been shown to survive three days, so far there are no scientific findings about how long the coronavirus can survive on clothing or textiles. However, in a 2005 study of the SARS virus, another coronavirus, it survived on cotton for five minutes to one hour depending on the amount of exposure.
Generally speaking, bags that are intended to last longer are made of heavier materials, so they use more resources in production and therefore have greater environmental impacts. To equal the relatively low global warming impact of plastic bags, paper and cotton bags need to be used many times; however, it’s unlikely that either could survive long enough to be reused enough times to equal the plastic bag’s lower impact. Ultimately, the single use of any bag is the worst possible choice. The key to reducing your environmental impact is to use whatever bags you have around the house as many times and in as many ways as possible. It’s understandable if, during this time of COVID-19, you’ve reverted to plastic bags to protect yourself and are probably discarding them after a one-time use. But when the risk of COVID-19 abates, remember to try to use whatever bag you choose as many times as possible. HDPE or LDPE bags can be used to store food, line wastebaskets, pick up dog poop, pack lunches, pad packages, stash wet umbrellas and in many more ways.
