Graduation Year

2006

Document Type

Dissertation

Degree

Ph.D.

Degree Granting Department

Public Health

Major Professor

Yehia Y. Hammad, Sc.D.

Keywords

Fungi, Indoor environmental quality, Contact dermatitis, Allergy, Asthma

Abstract

Bronopol has been used as a preservative in drugs and cosmetics since 1964. Bronopol has low dermal irritancy at levels commonly used in cosmetics and pharmaceuticals but it is significantly irritating at higher concentrations. Laboratory testing of bronopol indicates a low potential for dermal sensitization; however, a number of case reports demonstrate human allergenic reactions. No reports were identified on the allergenic properties of bronopol for the inhalation route of exposure. In 1983 approximately 5,200 people in the United States were occupationally exposed to bronopol. Current novel uses of bronopol include mold remediation and the sanitizing of ventilation system components. These new applications have the potential to expose vast new populations to the chemical. Since 89 million people in the United States work in indoor environments and 50 million Americans suffer from allergies, it is likely that a sizeable portion of these populations will be exposed to bronopol. This is significant since the dermal sensitizing properties of bronopol suggest that the material may also be a respiratory sensitizer, potentially resulting in chemically induced asthma. More people are being diagnosed with asthma today than at any time in the past; the causes of this increased prevalence are largely unknown. In this work an existing ultraviolet spectrophotometric method for analysis of bronopol has been combined with conventional industrial hygiene air sampling techniques. No combined air sampling and analytical method for bronopol has previously been published in the literature. A calibration curve has been developed with a linear range of 1 ug/ml to 25 ug/ml. The instrumental limit of detection is 1 ug/ml with an instrumental limit of quantitation of ca. 3 ug/ml. During chamber sampling trials analytical recovery for treated glass fiber filters yielded a sampling recovery efficiency averaging 99.9 %. Bronopol concentration obtained during chamber sampling trials ranged from 10.80 mg/m3 to 21.59 mg/m3, with a pooled coefficient of variation of 4.33 % for all chamber sampling sets. Treated glass fiber filters spiked with bronopol were found to be stable for a period of 48 hours; derivatized bronopol solutions were found to be stable for a period of fourteen days.

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