A Quantitative Health Risk Assessment for Stachybotrys chartarum-toxic mold

摘要

The inhalation exposure to Stachybotrys chartarum (SC) has been playing a critical role in public health due to its ability to produce toxins that are implicated in cases of acute idiopathic pulmonary hemorrhages (AIPH) in infants. Currently, there is no regulatory standard for acceptable level of SC spores/toxins in indoor environment. The goals of this study were to determine the risk of death in infants using the maximum reported concentration of toxins and spores in water-damaged residences and further provide a benchmark dose level above which an adverse effect may occur in human infants. The best fit dose-response models were derived from published animal studies and by using 10% as the benchmark response level, permissible exposure limits were obtained as 413 SC-spores/m3 or 3.94E-05 mg-toxin/m~3. The predicted risk of death in infants for acute 24-hour exposure to toxins ranged from 1E-4 to 3E-6. Uncertainty in risk estimates was characterized by conducting sensitivity analysis. The results indicated that while toxin exposure is inconclusive for AIPH in infants, a health hazard after inhalation of SC- toxins exists in human infants. Given the controversies surrounding the exposure and risk characterization of SC molds, these estimates should be interpreted with caution.