Assessment of fungal growth on sodium polyborate-treated cellulose insulation.
Cellulose insulation has rapidly gained a large market share among general contractors and homeowners. Recent interest regarding health effects of high concentrations of fungi within indoor environments (building-related illnesses or sick building syndrome) has promoted concern about susceptibility of building materials, including wood products (in general) and cellulose insulation (specifically), to fungal attack. This study reports an assessment of fungal growth on cellulose insulation made from recycled paper and treated with varying concentrations of sodium polyborate within half-scale wall units exposed to variable and high ambient temperatures and relative humidities throughout the summer. Boron-treated and untreated (control) cellulose insulation within the wall units were challenged with a suspension containing high concentrations of spores of five fungal species commonly found in indoor environments. Our results suggest that cellulose insulation treated with sodium polyborate (a) precludes the growth of the five common fungal species; (b) harbors fewer fungal species before and after being challenged with the fungal spore suspension; and (c) is likely having a cytotoxic or sporocidal effect on many, if not all, fungal species. These results suggest that cellulose insulation treated with sodium polyborate, when properly applied and installed, precludes fungal growth for at least 124 days at high temperatures and relative humidities.
Herrera
José
J
Division of Science, Office MG 3034, Truman State University, Kirksville, Missouri 63501, USA. jherrera@truman.edu
D016902:Air Pollution, Indoor / Q000517:prevention & control; D001895:Boron / Q000494:pharmacology; D001897:Boronic Acids / Q000494:pharmacology*; D002482:Cellulose; D003247:Conservation of Natural Resources; D003252:Construction Materials; D005658:Fungi / Q000254:growth & development*; D006813:Humidity; D011108:Polymers / Q000494:pharmacology*; D013696:Temperature
D001897:Boronic Acids; D011108:Polymers; D002482:Cellulose; D001895:Boron