Highways through historically redlined areas likely cause air pollution disparities today

As part of the New Deal, several government programs were created to increase home ownership through mortgages and loans. However, neighborhoods with predominantly black or immigrant communities were often considered “at risk” for repayment under discriminatory, “redlining” practices that restricted lending.

Today, the same areas are coming to the fore. Air pollution Compared to other citizens The neighborhoodand according to research published in Environmental Science and Technologythe reason may be related to nearby highways or industrial parks.

Between the 1930s and 1960s, groups such as the Federal Housing Administration and the Home Owners Loan Corporation (HOLC) worked to insure the loans, but they chose which neighborhoods received the funding. . Areas were graded from “A” (least dangerous) to “D”, considered the most dangerous, and color-coded red.

These red-lined neighborhoods were often home to black or Immigrant communities whose residents were routinely denied mortgages or loans as a result of the maps. During the same period, interstate highways passed through many of these communities, either isolating them or demolishing them entirely.

Recently, researchers showed Historically, air pollution levels are higher in red-lined areas. Compared to those who received higher ratings, and A similar disparity affects many American cities. Denver is one such city, where Joost de Goe and colleagues wanted to investigate the origin of the pollution gap.

The team collected satellite and computer modeling data. Nitrogen dioxide (no₂) and airborne fine particles (PM_2.5), both of which can be dangerous if inhaled. to combine Demographic data From the 2020 Census and historical maps produced by HOLC, the researchers found that neighborhoods classified with “D” had 13% higher levels of NO.₂ Compared to areas labeled “A”.

Across Denver as a whole, neighborhoods where the majority of residents identified as non-Hispanic white and Asian or Asian American were identified with lower NO.₂ And PM_2.5 Compared to areas that identify primarily as American Indian and Alaska Native, and Hispanic or Latino.

The researchers also investigated potential sources of NO.₂ And PM_2.5 Emissions that affect the first red line areas. They discovered that diesel-powered vehicles emit about half the nitrogen oxides of on-road vehicles, while additional pollutants such as benzene come from other point sources, including nearby petrochemical refineries.

Many of Denver’s major highways and industrial areas, including Commerce City, are surrounded by diverse communities that generally have fewer people who identify as non-Hispanic white, although this group is a significant portion of the city’s population. It is a big part. The researchers say the work helps identify areas that could be most improved by reform programs such as clean technology incentives.