This paper reports the results of a study relating levels of particulate matter to daily deaths
in Delhi, India between 1991 and 1994. We focus on Delhi, the capital of India, because it is one
of the world’s most polluted cities. During the study period, the average total suspended
particulate (TSP) level in Delhi was 378 micrograms per cubic meter--approximately five times
the World Health Organization’s (WHO) annual average standard. Furthermore, TSP levels in
Delhi during this time period exceeded the WHO 24-hour standard on 97 percent of all days on
which readings were taken.