Comment on

• Oxygen saturation, pulse rate, and particulate air pollution: A daily time-series panel study.

  Pope CA3rd, Dockery DW, Kanner RE, Villegas GM, Schwartz J. Pope CA3rd, et al. Am J Respir Crit Care Med. 1999 Feb;159(2):365-72. doi: 10.1164/ajrccm.159.2.9702103. Am J Respir Crit Care Med. 1999. PMID: 9927345
• Long-term inhalable particles and other air pollutants related to mortality in nonsmokers.

  Abbey DE, Nishino N, McDonnell WF, Burchette RJ, Knutsen SF, Lawrence Beeson W, Yang JX. Abbey DE, et al. Am J Respir Crit Care Med. 1999 Feb;159(2):373-82. doi: 10.1164/ajrccm.159.2.9806020. Am J Respir Crit Care Med. 1999. PMID: 9927346