How dividing US cities along racial lines led to an air pollution crisis. 100 years of Study of 200 cities shows dangerous environmental inequality fueled by 20th-century practice of redlining. A new study has found that neighborhoods in which the federal government discouraged investment nearly 100 years ago – via a racist practice known as redlining – face higher levels of air pollution today. Looking at more than 200 cities across the nation, researchersfrom the University of California, Berkeley, found that people who live in neighborhoods that were once categorized as “hazardous”, based on racist factors such as how many Black or “foreign-born” people lived there, now breathe 56% more of the freeway pollutant nitrogen dioxide than those in top-rated areas.  Those formerly redlined neighborhoods also suffer from higher levels of the sooty particle known as PM 2.5, the study found. And both pollutants are associated with health effects, including higher rates of asthma, cardiovascular disease and even Covid-19. “The people who made the decision [to redline certain neighborhoods] aren’t even alive any more,” said Joshua Apte, a UC Berkeley environmental engineering professor, who co-authored the study, published in Environmental Science and Technology Letters on Wednesday. “But the decisions made a long time ago still matter quite a lot for the disparities experienced today.” In the 1930s, the federal government created a series of maps that indicated where Black people, immigrants, and other groups of the people that they considered “too risky” to have as neighbors lived, and used those maps to discourage mortgage lending in those neighborhoods.This process was known as redlining, because the makers of those maps shaded those areas in red. The Berkeley research illustrates how those discriminatory maps, created by the federal Home Owners’ Loan Corporation between 1935 and 1940, shaped urban development and real estate practices for nearly a century afterwards. It concludes that the maps helped to shape present-day locations of roads, freeways, industrial facilities, ports, and other major sources of pollution, thus influencing which neighborhoods have clean air today. “Our findings illustrate how redlining, a nearly 80-year-old racially discriminatory policy, continues to shape systemic environmental exposure disparities in the United States,” wrote the study’s lead author, Haley Lane, a researcher in civil and environmental engineering at UC Berkeley.        https://www.theguardian.com/us-news/2022/mar/09/redlining-air-pollution-us-cities