Research

My research group focuses broadly on the human health effects of exposures to chemicals in the environment.

Pesticides:  Pesticides are commonly used chemicals, but few people are able to accurately characterize their exposure.  Many of the currently used pesticides have short biological half-lives; good for us and the environment, but bad for trying to assess long term exposure to pesticides.  While the general public does not have good recall about pesticide use, farmers do.  Pesticides are a business expense and farmers can provide information about the specific chemicals that they use.  Because similar chemicals are used in farming and in residential and public health applications, studies of farmers allow us to understand the potential human health effects of pesticide use.

My research has focused predominantly on the respiratory and allergic consequences of pesticide use in farmers and their spouses in the Agricultural Health Study using questionnaires to evaluate exposure and outcomes.  My current projects are building toward biological measures from highly exposed populations with more detail on respiratory and allergic diseases.  I am also collaborating with pesticide educators to help communicate epidemiologic findings to farmers and their families using appropriate tools and delivery methods.

I am currently funded by NIEHS to study the respiratory health effects of pesticide exposure in women and children living in the banana growing region of Costa Rica.  The ISA cohort was started by Dr. Berna van Wendel de Joode to follow pregnant women and their children for health effects.  We hope to expand this study over time.

This work is supported by two NIEHS grants.

R21 ES025374 (Hoppin/Van Wendel de Joode)  Environmental pesticide exposure and respiratory outcomes in women and children

This project assesses pesticide exposure and respiratory symptoms in young children and their mothers living in the primary banana-producing region of Costa Rica, a region with high environmental pesticide exposure.

R24 ES028526-01A1 (Hoppin/Van Wendel de Joode)  Maintaining and enriching the Infants Environmental Health Study (ISA) 

This project will provide ongoing maintenance, data support, and followup of the ISA cohort in Costa Rica.  This study will continue to follow ~300 women and their children to understand the human health effects of pesticide exposure.  This project includes collaborators at UNA in Costa Rica, Lund University in Sweden, and NC State.

PFAS: Per- and poly fluoroalkylated substances (PFAS) are persistent environmental contaminants associated with chemical manufacturing, non-stick products, and fire fighting.  Drinking water contamination around the United States is common.  Here in North Carolina, GenX and other newly identified PFAS chemicals were found in the drinking water of Wilmington, NC, due to chemical manufacturing upstream on the Cape Fear River.  We are currently investigating whether these chemicals persist in people’s bodies and whether they are associated with health outcomes.

This work is funded by an NIEHS time sensitive R21.  We recently received a supplement to study the population living around the Chemours facility in NC.  We have also received matching funding from the NC Policy Collaboratory for additional specimen collection and science communication efforts.

ES029353 (Hoppin)   Assessing impact of drinking water exposure to GenX (hexafluoropropylene oxide dimer acid) in the Cape Fear River Basin, North Carolina

The goal of this project is to conduct a community-based study to assess human exposure by measuring GenX in biological samples of community residents.

Phthalates: Phthalates are a class of chemicals used for a variety of purposes from consumer products and fragrances to plastic tubing and rain coats.  Exposure in the United States spans three orders of magnitude for some of these chemicals, but due to the short half life and variability of exposure, classifying an individuals long-term exposure has been challenging.  My research has focused on current exposure response relationships, such as current phthalate exposure and current allergic symptoms.  We are continuing to assess short term responses to be able to link to the short term response from toxicology studies.  I am also interested in better characterizing sources of phthalate exposure.  Doctoral student Gina Hilton and I published a paper suggesting that H. pylori infection was associated with increased exposure to mono-ethyl phthalate. Paula Strassle from UNC and I published a paper looking at the interaction between phthalates and endotoxin on respiratory outcomes in adults.