I just had my attic insulated using cellulose. Inside the house started to smell very pungent and nauseating despite leaving all windows and doors open all day and night. 24 hours later smell still there. Can someone tell me what the smell is about and how to get rid of it. It is causing some burning sensation in my chest, migrain like headache and palpitation.

Thank you

Do you know the maker of the insulation and what was installed?

The material is cellulose that apparently was locally made

Cellulose is treated with a fire retardant. That may be one reason. Do you have can lights, if so, are they Insulation Contact-IC? If not, the insulation may be over the can and needs to be 6 inches away. Could be overheating the insulation.