title: Evaluating the health significance of hazardous air pollutants using monitoring data.
abstract: OBJECTIVE
  Though many contaminants are released into the atmosphere, in the US only six air pollutants-ozone, particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, and lead-are closely monitored and carefully assessed for health significance. Other pollutants, even if highly toxic, are neither widely monitored nor routinely assessed at the national level. The goal of this study was to analyze the availability of information needed to characterize the health significance of hazardous air pollutants, focusing on urban areas in California.
  
  
  METHODS
  The authors compared different approaches to identifying which contaminants should be considered hazardous air pollutants of potential health concern; reviewed the availability of toxicity values for these pollutants; and analyzed the usefulness of air monitoring data from California agencies for determining populations risks, by comparing method detection limits with health benchmarks.
  
  
  RESULTS
  Approaches to identifying air contaminants of possible health concern differ. Toxicity values are not available for many hazardous air pollutants, including those identified in the Clean Air Act. In California, monitoring data are available for many, though not all, pollutants of concern. Monitoring methods for several pollutants do not have adequate sensitivity to detect all relevant concentrations.
  
  
  CONCLUSIONS
  The information necessary to fully assess the health significance of hazardous air pollutants is not currently available.
authors.affiliation: School of Public Health, University of California, Berkeley, 94729-7360, USA. adkyle@socrates.berkeley.edu
authors.forename: A D
authors.initials: AD
authors.lastname: Kyle
authors.forename: C C
authors.initials: CC
authors.lastname: Wright
authors.forename: J C
authors.initials: JC
authors.lastname: Caldwell
authors.forename: P A
authors.initials: PA
authors.lastname: Buffler
authors.forename: T J
authors.initials: TJ
authors.lastname: Woodruff
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis*; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis* / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data; D019985:Benchmarking; D002140:California; D003627:Data Interpretation, Statistical; D004782:Environmental Health; D004784:Environmental Monitoring / Q000331:legislation & jurisprudence / Q000379:methods* / Q000592:standards* / Q000706:statistics & numerical data; D019317:Evidence-Based Medicine; D006801:Humans; D015233:Models, Statistical; D020380:Needs Assessment; D011634:Public Health; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014481:United States; D014484:United States Environmental Protection Agency; D014504:Urban Health / Q000706:statistics & numerical data*
chemical_list: D000393:Air Pollutants