More than 4 months of tear gas in Portland raises concerns for environmentBy Monica Samayoa (OPB)Portland, Ore. Oct. 23, 2020 1 p.m. Updated: Oct. 23, 2020 4:28 p.m.The answers become murky when it comes to what tear gas and pepper spray chemical agents do to the environment.📨 Daily news in your inboxSign up today for OPB’s “First Look” – your daily guide to the most important news and culture stories from around the Northwest.EmailPlease leave this field blankSign up