Environmental Groups Suing DHS Over Tear Gas Use In Protests

A lawsuit was filed regarding the use of tear gas at Portland protests, accusing the Department of using excessive dangerous weapons without considering environmental impacts. The groups involved are urging the DHS to cease using chemicals like tear gas until their effects on health and the environment are studied.

What is the duration of the lawsuit's claims regarding the use of tear gas?

What are the environmental concerns mentioned in the lawsuit?