The writing process for the majority of Metallicaâs albums have followed the same process. A large slew of guitar riffs written primarily by James Hetfield, sometimes Kirk Hammett, and rarely the bandâs bass player, (that now being bass virtuoso Robert Trujillo) are reviewed and selected.
1 Delhi is most polluted city in the world in PM2.5 concentrations. 2  Half of the top 20 most polluted cities were in India, according to data.  PM2.5 is considered most harmful to health.
Los Angeles again tops the list of cities that have the worst ozone pollution in the U.S., according to a new report released Wednesday.Share This Story. The city has topped the dirty air list in 14 of the 15 annual State of the Air reports released so far.everal cities have reduced air pollution levels. Los Angeles, for example, reduced over one-third of unhealthy ozone days in the past 15 years. Pittsburg too has lowered its particle pollution levels.