Conference Agenda

The advent of herbicide-tolerant, genetically modified (GM) crops led to rapid and widespread use of glyphosate throughout US agriculture—applications increased more than 750% in the decades following GM-seed introduction. However, science/policy remains unresolved regarding glyphosate's human health effects. We identify the causal effect of glyphosate exposure on perinatal health. We combine (1) county-year glyphosate-application variation driven by (2) timing of GM technology and (3) differential geographic suitability for crops. We find glyphosate reduced average birthweight and gestation. Low-weight births experienced the largest reductions. Together, these estimates suggest that glyphosate exposure caused previously undocumented and unequal health costs for rural US communities over the last 20 years.

I study a phenomenon of hastened technology adoption facilitated by a negative spatial externality. GMO seeds have been engineered to withstand the application of particular weedkillers: farmers can use them in-crop, killing the weeds, leaving the crop unscathed. I show that the adoption of such seeds generates negative externalities on downwind neighbors, increasing the probability of the adoption of the same seed by 29% as well as a conversion of cropland to different crops able to withstand the weedkiller. Overall yields remained unchanged as the benefits of the weedkiller on yields are offset by the negative effects of crop failures for neighbors. Consequences of such rapid adoption include possible monopolization on the seed market.

This paper estimates the cost of noncompliance with the French policy of mandatory insecticide application to control Flavescence dorée, an epidemic pest disease plaguing European vineyards. To account for reverse causality between compliance rates and the spread of the disease, we leverage incentives to comply through the returns of wine production stemming from century-old Appellations d'Origine Contrôlée. We find that increasing the average noncompliance rate by 10 pp increases the average probability of disease presence by 4.5 pp. Our results suggest that increasing compliance can increase welfare if the environmental and health costs from one insecticide application are below \euro 50/ha.

Agriculture is the main source of food, the major source of income for the global poor, and a key driver of global deforestation and pollution. Here, we show that the adoption of genetically modified (GM) crops by some countries has led to a global redistribution of agricultural production and its associated externalities.

To estimate the effects of GM crop adoption on the global redistribution of agriculture, we develop a regression framework that captures local effects and the spillovers in a single reduced-form equation based on the recent trade literature. Further, to address the endogeneity of the adoption decision, we predict GM crop adoption with the approval of GM crops for consumption by the countries' trade partners.

Our results show that local GM crop adoption has no impact on total agricultural area in adopting countries but a positive impact on GM crop shares, indicating that GM crop expansion occurs at the expense of crops without GM varieties and not on non-agricultural land. We also find that agricultural production increases in adopting countries while it declines in non-adopting countries, suggesting the reallocation of agricultural production to adopting countries. Additionally, the results show that GM adoption leads to an increase in herbicide use and a decrease in insecticide use.