Date of Award

10-20-2023

Document Type

Thesis

Department

Biology

First Reader

Dr. Sara Hubbard

Second Reader

Dr. Angela Douglass

Third Reader

Dr. Maddie Myers-Burg

Abstract

Bisphenol-A (BPA) is a compound commonly used as a stabilizer in plastic products, including food storage containers and thermal paper receipts. Because BPA can bind to and activate estrogen receptors, it is linked to reduced fertility, altered development, and hormone-related cancers. A recent study at NYU Medical School confirmed the presence of BPA in pantyliners, pads, tampons, feminine washes and deodorants. This is concerning due to the high absorption capacity of the vulvar skin.

For the research performed in our lab this summer, the goal was to determine if fluorescence spectrophotometry could be used to determine the presence of BPA in feminine hygiene products by monitoring the release of BPA over time into a solution of 50% methanol/water. Fluorescence is a sensitive, selective and affordable method of analysis, and BPA is a fluorescent compound that absorbs energy at 278 nm and emits at 304 nm. First, a calibration curve was obtained and analytical figures of merit were determined: linear range, limit of detection and limit of quantitation. Due to the complex sample matrix and the small concentrations of BPA in these products, the standard addition method was employed for analysis. Pantyliners, tampons and tampon applicators were tested for the presence of BPA.

The top/outside layer of the feminine hygiene product which comes into direct contact with skin was removed and cut into small pieces. In the case of tampon applicators, the entire applicator was utilized. Samples were then placed into beakers containing 100 mL of 50% methanol/water solution, one per time point to be tested from 0 minutes to 6 hours. At each time point, aliquots of sample solution were removed and transferred to 25-mL volumetric flasks containing various concentrations of BPA stock solution and diluted to 25-mL with 1:1 methanol/water solution. Fluorescence emission intensities at 304 nm were obtained in quadruplicate, and standard addition graphs were utilized to determine the concentration of BPA that had leached from the sample at each time point. Graphs were prepared using these values to produce a visual representation of BPA leaching from the sample over time.

The results showed that both the generic and name-brand pantyliner and tampon samples leached BPA while the luxury brand’s products did not. For both the generic and name-brand samples, the tampon applicator released more BPA into solution over time than the absorbent component. Of the generic brand’s three products, the pantyliners leached the most BPA into solution. For the name-brand’s three products, the tampon applicators leached the most BPA into solution.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.