SEATTLE – There has been a 50 percent reduction in the number of plastics bags in residential garbage since Seattle enacted its plastic bag ban in 2012, according to Seattle Public Utilities. Now the utility's Waste Prevention Manager is trying to find ways to encourage people to wash their reusable bags.

“We’ve heard from retailers that people are doing a great job of using reusable bags, but some people are coming in with bags that are pretty dirty,” said Sego Jackson, Waste Prevention Project Manager for Seattle Public Utilities. “I think if people haven’t been washing their bags – the first step is just start doing it.”

There has been publicity in the past about a study discovering germs on bags and a case where norovirus was blamed for sickening a group of soccer players. Researchers later reported a contaminated reusable bag was the source.

James Apa, a spokesman for King County Department of Public Health, said that staff didn’t have any knowledge of communicable disease outbreaks associated with reusable bags locally.

“However, it’s a good idea to clean them regularly,” he said. “You can put them in the washing machine on medium temperature.”

Shoppers and tourists near Seattle’s downtown core had varying views of bag washing.

“It’s just kind of something I think I should do then I forget when I get home, put them away and forget about it,” Olivia Bojan said.

She said she’s had a set of bags for about a year and they need washing.

Donalee Quinn said she keeps her bags separated.

“I have a bag for produce so when I end up with leaves and little food debris from fruits and vegetables – then I empty it out in the trash or yard every once in a while,” she said. “The reusable bags that I’ve ever received are indestructible. I wish I had clothing that was made out of recyclable grocery bags.”

Sego Jackson pointed to suggestions from the cleaning institute, which detail different cleaning instructions for different types of bags. He said SPU is considering how it will raise awareness about bag cleanliness. Reaching out through its website and its newsletter are likely on the table. Jackson also wants to start a discussion with retailers about education. Notifying people about washing instructions at bag-giveaways is another option.

“I think what’s most important is for people to do what works for them. You’ll see they say wash them every time you use them. That’s not what my family does. We do it every few times that we use them,” Jackson said. “The easiest thing to do is – any time you see a problem … wash your bag and then do it on a regular basis. Just like we wash everything else on a regular basis, your shopping bag should be washed also.”