PLEASE HELP ME I’LL MAKE SURE TO GIVE YOU THE YELLOW CROWN IF YOU GET IT RIGHT!!

Answer:
Chemical Hazard; pollutant
Explanation:
Poison ivy contains a oily substance called urushiol. It reacts with the proteins in your skin and alerts the T-cells of the 'danger'. The T-cells may take a few days to create more T-cells to battle the urushiol.