Smoky Hangover on New Year’s Day

Residents of Mexico’s capital began 2005 breathing air that was more polluted than normal, as the high number of fireworks and wood fires lighted during thousands of New Year’s celebrations left a dense, gray pall over much of the city, authorities said.

In some northeast Mexico City neighborhoods, ozone levels climbed above 190 on a scale that uses 100 as the cutoff at which air is considered unhealthy.

Mexico City often exceeds the 100-point ozone mark, but Saturday’s unsatisfactory rating was noteworthy because air quality usually improves on holidays, when streets normally clogged with traffic day and night are relatively empty.