Lateral view of a zebrafish developmentally-exposed to nonylphenol ethoxylate and aged to 30 days. Nile Red stain fluorescently labels the fat cells throughout the fish.

Metabolic Disruption of Common Surfactants

Currently funded through a K99/R00 award from NIEHS, this project aims to explore the potential metabolic disruption potential of alkylphenol and alcohol polyethoxylates, a group of common surfactants added to hard surface cleaners, detergents, paints, and other common consumer products. Our goals are to:
1) Identify potential metabolic health impacts (adiposity, altered growth) on developmentally-exposed zebrafish. 
2) Identify potential causal mechanisms through which these chemicals exert their effects on metabolic health.
3) Assess the relative contribution of these chemicals to metabolic impacts of environmental mixtures.

Metabolic Disruption of Environmental
​Contaminants and Mixtures

I'm interested in pursuing various experiments to better characterize the metabolic disruption potential (ability to promote fat cell differentiation and proliferation) of environmental contaminants and mixtures. We've published previously on the ability of dozens of indoor contaminants and several types of environmental mixtures (e.g. indoor house dust and hydraulic fracturing wastewater) to promote both differentiation and proliferation in cell models. 

​We utilize cell-based adipocyte differentiation assays (pre-adipocyte and mesenchymal stem cell models in various species), along with developmental exposures in zebrafish & mouse models.

You can listen to a webinar I gave on this topic here.

Visualization of differentiated 3T3-L1 pre-adipocytes. Yellow = Nile Red lipid stain; blue = Hoechst DNA stain (cell number).

A natural gas well in Garfield County, Colorado, an extremely dense unconventional oil/natural gas production region.

Identifying and Characterizing Endocrine Disrupting Chemicals

I have a great interest in pursuing novel endocrine disrupting chemicals and their mechanisms of action. 
​
​This work has previously focused on novel environmental sources of endocrine disruptors like hydraulic fracturing and unconventional oil and gas production and residential household dust, and have several new directions in mind!

We utilize cell-based reporter gene assays and cell-free receptor binding affinity assays to identify the molecular mechanisms these chemicals and mixtures promote, and HRMS and novel chemical isolation techniques to identify the causal chemicals responsible for these effects.

You can listen to a webinar I gave on this topic here.

Assessing Health Risks from Exposure to
​Environmental Contaminant Mixtures

I have great interest in pursuing endocrine disrupting chemical mixtures and their potential impacts on human/animal health.

​This work has previously focused on using whole environmental samples or extracts (unconventional oil and gas wastewater, municipal wastewater, residential household dust, silicone wristband extracts, and human serum). We work to measure biological activities (e.g. receptor activation or inhibition, adipocyte development) and associate these activities with human and animal health outcomes. We previously demonstrated that the extent of house dust-induced fat cell development was significantly associated with the BMI of residents in these homes.

​We utilize whole mixture testing in cell-based assays and animal models (primarily zebrafish) along with CRISPR mechanism testing to identify outcomes and understand mechanistically how mixtures act. We also collaborate with statisticians to better model mixtures and outcomes.​

Humans and animals are regularly exposed to complex mixtures of hundreds/thousands of chemicals, most of them not regulated, with uncertain health effects.