There is no getting around the fact that insulation is far from chemical free, but it is an essential ingredient to help keeping our homes nice and cool in the summer and toasty warm in the winter. Fiberglass batt insulation is itchy, causes rashes and respiratory problems, and is a known carcinogen when inhaled with attic dust. Newly installed loose fill fiberglass insulation is slightly better for respiratory effects, is not as itchy and relatively inert. In both types of fiberglass insulation you will find rodents, critter infestation and its feces if they are present in your attic. Cellulose insulation tends to be a rodent repellent due to the added boron. Although cellulose insulation gets labeled as the greenest type of insulation because it’s primary component is recycled newspaper, there are still a good amount of chemicals directly mixed in such as boron and boric acid and indirectly such as old ink, dyes, solvents, formaldehyde, chlorine, fluorine, lead, iron compounds, sulfur compounds, cadmium, nitric oxide and methane. These trace chemicals are estimated to account for 20% of the composition of cellulose insulation.