Vaporized Formaldehyde Treatment of a Textile Mill Contaminated With Bacillus anthracis

Abstract

Contamination with Bacillus anthracis spores is a serious environmental hazard in textile mills where imported raw goat hair is used. While a plant in which haircloth had been produced was being converted for synthetic fiber production, formaldehyde vapor was introduced into the sealed buildings at a final concentration of 1.38 to 1.62 ml/cu ft (18 to 21 mg/liter). Pretreatment rates of surface contamination with anthrax spores were 37% in the initial processing area and 12.5% in the spinning area. Contamination dropped to 8% and 1% immediately after formaldehyde treatment, and to 1% and 0 six months later. Test suspensions of B anthracis spores placed in the plant before it was treated showed 99.998% loss of viability and recovery of all bacterial flora had been reduced tenfold to 100-fold after treatment.