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.
More than half of the countryâs most-smog-polluted cities experienced their best year yet. All metro areas in the 25 cities most-polluted by ozone showed improvement over last yearâs report. Still nearly half the people in the US (48.2%) live in areas with unhealthful levels of ozone pollution.