Looks like lead paint walls and asbestos insulation better be careful also in st.louis mo I saw 3 guys get in huge trouble for demo work on an old house. I believe the rule is if you plan to demo more than a 6×6inch section you have to have the proper ventilation to protect the neighbors from lead dust. I believe they call it lead abatement
I know you said that is not asbestos but did you test? It looks very, very much like chrysotile insulation that is notorious for asbestos lawsuits (there is a website setup for remediation compensation). Either way, a full N100 respirator is in order when dealing with demoing walls. Your lungs will thank you.