I am a Ph.D. Candidate in Agricultural and Resource Economics at the University of California, Davis.
My research lies at the intersection of agricultural, environmental, and health economics, with a focus on the unintended consequences of environmental and agricultural policies. I combine spatial water network datasets, remote sensing data, and applied econometric methods to quantify the impacts of agrochemical exposure and land use change.
My dissertation investigates (1) the neonatal health effects of glyphosate exposure through waterborne pathways in the U.S. Corn Belt and (2) the deforestation and carbon emissions associated with global demand for biomass-based diesel, particularly through palm oil expansion in Southeast Asia.
Research in Progress
Chen, Tzu-Hui. 2025. Glyphosate Use, Water Contamination, and Neonatal Health in the United States (Revise & Resubmit, Journal of the Association of Environmental and Resource Economists) [PDF]
Abstract. This study investigates the impact of glyphosate, the most widely used herbicide, on birth outcomes in the US Corn Belt. Using water flow mechanisms to identify causal effects, the study shows that glyphosate affects populations far from application sites through waterborne transmission. The results suggest that a 10 kg/km2 increase in upstream glyphosate use led to a 4.6 percent rise in neonatal deaths in lower-income areas, with no observed effects in higher-income regions. The research design also incorporates variations in spatial distances, seasonal exposure patterns, and rainfall data to ensure that the observed health impacts are attributable to glyphosate. Evidence suggests avoidance behaviors and water treatment are potential mechanisms of the heterogeneous effects.
Abstract. This study investigates the impact of glyphosate, the most widely used herbicide, on birth outcomes in the US Corn Belt. Using water flow mechanisms to identify causal effects, the study shows that glyphosate affects populations far from application sites through waterborne transmission. The results suggest that a 10 kg/km2 increase in upstream glyphosate use led to a 4.6 percent rise in neonatal deaths in lower-income areas, with no observed effects in higher-income regions. The research design also incorporates variations in spatial distances, seasonal exposure patterns, and rainfall data to ensure that the observed health impacts are attributable to glyphosate. Evidence suggests avoidance behaviors and water treatment are potential mechanisms of the heterogeneous effects.
Indirect Land Use Changes: Biofuel Demand and Deforestation in Southeast Asia with Aaron Smith, Richard Sexton
Abstract. Biomass-based diesel (BBD) fuel has emerged in many countries as a key tool to replace fossil fuels and reduce carbon emissions and other pollutants. This study quantifies the environmental costs of BBD by linking palm oil-driven deforestation to rising global vegetable oil demand. Using remote sensing and econometric analysis, I estimate the impact of BBD on land-use change in Indonesia and Malaysia and assess associated carbon emissions. Results suggest that global BBD consumption between 2002 and 2018 caused approximately 1.6 million hectares of deforestation in Indonesia and Malaysia. Even without accounting for emissions from these other sources, the carbon intensity of BBD from forest-to-palm conversion alone exceeds that of fossil diesel.