Research

Abstract: In 2012, the US and Canada implemented a technological regulation, called the ECA (emission control area), in their exclusive economic zone to reduce emissions from ocean-going ships. The ECA required ships to use low-sulfur fuel, increasing a ship’s main operating cost. The EPA estimated that the operational cost of ships would increase by $18 for a twenty-foot-equivalent container. Operation costs, however, are not the only costs of regulation. In international trade, fuel and capital are substitutes and an increase in fuel prices leads to demand for larger (more fuel-efficient) ships. In this paper, I use data from 2006 to 2016 on commercial container ships’ calls to US ports, from the Army Corps of Engineers, to construct a panel at the port-quarter level that tracks ship size and port exposure to the ECA for all US ports. Port exposure measures the average time a ship operates in ECA-regulated waters before reaching said port. I use the variation in port exposure to estimate the relative change in ship size for more exposed US ports after the ECA. I find the ECA led to about 3\% larger ships for ports further along container routes. This is driven by larger ships shifting to serve the more exposed US ports. These findings show that fuel regulations favor larger ships, with implications for container movement along trade routes and investments for port expansions.

Abstract: Per- and Polyfluoroalkyl Substances (PFAS) are a family of man-made chemicals detrimental to human health. Despite widespread exposure to PFAS, evidence of avoidance behavior remains limited. This paper estimates the effect of information provisions on the avoidance of PFAS exposure. Past research quantified how individuals avoid exposure to chemicals, such as E-coli or lead, when notified by measuring additional bottled water purchases. The case of PFAS is unique; the full health effects of PFAS are relatively uncertain, and PFAS stays in drinking water longer than other common contaminants. Our work contributes to the literature by examining how individuals affected by emerging PFAS contamination respond to information and by estimating the extent to which people continue to be exposed to PFAS, even after being informed. We leverage variation in PFAS Maximum Contaminant Level (MCL) violations across nine states for the years 2019 to 2023 to quantify these impacts. We employ a two-way fixed effects design, pairing detailed violation data at the weekly level with Nielsen retail scanner data, including purchases of bottled water and water filters per store. Our results show water filter purchases increase by 6\% in the week following a violation and no significant increase for bottled water. This increase represents a community-level cost of approximately $60,000 for each violation and $11.5 million over our sample. These results show that consumers spend significantly more on durable filters to protect themselves in anticipation of exposure over the long run, rather than investing in short-run solutions, like bottled water.