Question

Q3 between 1950s and early 1070 s ; why did pollution begin to draw major public attention in United States​

Answer 1

Answer:

In the 1950s, 1970s, and 1990s, the United States Congress enacted a series of Clean Air Acts which significantly strengthened regulation of air pollution. Individual U.S. states, some European nations and eventually the European Union followed these initiatives. The Clean Air Act sets numerical limits on the concentrations of a basic group of air pollutants and provide reporting and enforcement mechanisms. The United States Environmental Protection Agency (EPA) is the federal agency responsible for creating and enforcing regulations that implement these laws.

The effects of these laws have been very positive. In the United States between 1970 and 2006, citizens enjoyed the following reductions in annual pollution emissions:

carbon monoxide emissions fell from 197 million tons to 89 million tons

nitrogen oxide emissions fell from 27 million tons to 19 million tons

sulfur dioxide emissions fell from 31 million tons to 15 million tons

particulate emissions fell by 80%

lead emissions fell by more than 98%

A 2020 paper published by researchers at MIT found that about half of air pollution and half of the resulting deaths are caused by emissions from outside a given state's boundaries, typically from prevailing winds moving west to east. Regulation of air pollution is split between federal, state, and local governments.

Since 1999, the EPA has used the air quality index (AQI) to communicate air pollution risk to the public, on a scale from 0 to 500, with six levels from Good to Hazardous. (The previous version was the Pollution Standards Index (PSI), which did not incorporate PM2.5 and ozone standards.)

The actual standards for pollutant levels defining "attainment" and "non-attainment" areas for compliance purposes for six major pollutants are the National Ambient Air Quality Standards. These are required by law to be reviewed every five years, as new scientific information becomes available on the health and property impacts of pollution. These reviews typically cause political controversy as tighter requirements can have economic consequences for automobile manufacturers and companies that emit pollutants. State and local governments are responsible for enacting and enforcing regulations that achieve the federal standards, by limiting emissions from local sources