Pesticides are linked to negative health outcomes, but a causal relationship is difficult to establish due to nonrandom pesticide exposure. I use a peculiar ecological phenomenon, the mass emergence of cicadas in 13 and 17-year cycles across the eastern half of the US, to estimate the short and long-term impacts of pesticides. With a triple-difference setup that leverages the fact that cicadas only damage tree crops and not agricultural row crops, I show that insecticide use increases with cicada emergence in places with high apple production. Exposed cohorts experience higher infant mortality and adverse health impacts, followed by lower test scores and higher dropout rates. I exploit geo-spatial sources of variation and find evidence for pesticide exposure through a water channel. Moderate levels of environmental pollution, not just extreme exposure, can affect human health and development. The study design, which encompasses the entire chemical era of US agriculture since 1950, provides insights into the regulation of pesticides in the US and globally.
That is Charles Taylor, a job market candidate from Columbia’s Sustainable Development PhD program, in his brilliantly titled paper, Cicadian Rhythm: Insecticides, Infant Health and Long-term Outcomes.
His cost-benefit analysis on the value of buying organic (in brief):
Applying my results to a back-of-the-envelope calculation, 556 infant deaths can be attributed to insecticides in the limited context of apple production and cicadas, equating to a total welfare loss of $5.3 billion using the EPA’s value of statistical life of $9.6 million (2020 dollars),1 or $81 million annually from 1950 to 2016. The annual value of apple production in the sample counties ranged from $500 million to $1 billion in recent decades, so this cicada-driven response of infant mortality to insecticides could account for 8-16% of apple production value. For reference, organic apples cost 5-10% more to produce than conventional ones (Taylor and Granatstein 2013), suggesting that organic production may be cheaper after accounting for the social cost of insecticides. However, apple production in the eastern US accounts for only 0.5% of US pesticide use, so if these effects scale across other crops, the total welfare cost of insecticides could be 200x larger
Image from The Atlantic.