This 25 August 2020 video about Oregon in the USA says about itself:
Tear gas poisoning river in Portland
Officials fear that tear gas will pollute Portland’s rivers.
During on-going protests across Portland, government officials now fear that the excessive amount of tear gas is polluting the Willamette River.
The tear gas in Portland is applied by local police and by Donald Trump’s ‘stormtroopers’ against demonstrators against racism and against police brutality.
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