Mexico City, Mexico – Move over, Mexico City, a think tank study says the country's most damaging air pollution is in the border city of Mexicali.

The nation's capital has long had a reputation for smog, but in small particle pollution it registered in about the middle of large Mexican cities studied.

But Mexicali, a municipality of almost a million people across from Calexico, California, has excessive dust that gave it the highest per-capita rate of pollution-related premature deaths, hospital and doctor visits.

Small particle pollution was above recommended limits in almost all of the 12 Mexican cities over 500,000 inhabitants in the study by the Mexican Institute on Competitiveness.

The study, which was released Tuesday, also found remarkably high rates of health problems caused by air pollution in the central city of Cuernavaca, and the northern cities of Monterrey and Tijuana.