Propylparaben is a chemical with antimicrobial properties used in cosmetics and packaged foods. Prior studies indicate that it can bind to the estrogen receptor and is considered an endocrine-disrupting chemical. My project investigates the effects of propylparaben administered during perinatal development. 

More specifically, we have been quantifying developmental changes in the mouse mammary gland that are likely due to hormonal disruptions from propylparaben. Whole-mounted mammary glands were collected from female mice at postnatal  

Day 21 (prior to puberty) and postnatal day 32-35 (during puberty). I have collected images of these mammary glands using a Zeiss AxioImager dissection microscope and analyzed their morphological features using ZEN software. At day 21, I have measured the area subtended by the ducts and branching points, as well as the width of the central lymph node and total ductal extension. For days 32-35, I have measured ductal area, number, and area of terminal end buds, and ductal extension. 

Evaluating changes to the mammary gland prior to puberty allows us to understand whether propylparaben can affect baseline development, prior to the onset of high endogenous hormone production associated with puberty. Changes observed in the pubertal samples can indicate that early life exposures to propylparaben alter the female’s responsiveness to her own endogenous hormones. 

This work is critical to understand the impact of propylparaben exposures on health outcomes. This is important to human health since propylparaben is used in items that we use in our daily lives and we should know the effects it has.