title: Impact of 2013 south Asian haze crisis: study of physical and psychological symptoms and perceived dangerousness of pollution level.
abstract: BACKGROUND
  The widespread forest fires in Indonesia in June 2013 led to widespread haze to neighbouring countries. This is the first study in the medical literature reporting the acute physical and psychological symptoms of the general population during a haze crisis. We evaluated the factors that are associated with psychological stress of haze exposure.
  
  
  METHODS
  This study was conducted between June 21 to June 26, 2013. Participants were recruited by an online recruitment post and snowball sampling techniques. Participants were required to complete an online survey which was composed of demographics questionnaire, physical symptom checklist, perceived dangerous Pollutant Standard Index (PSI) value and views on the N-95 mask and the Impact of Event Scale-Revised (IES-R).
  
  
  RESULTS
  A total of 298 participants returned the completed study questionnaire. The respondents reported a mean number of 4.03 physical symptoms (S.D. = 2.6). The five most common physical symptoms include mouth or throat discomfort (68.8%), nose discomfort (64.1%), eye discomfort (60.7%), headache (50.3%) and breathing difficulty (40.3%). The total IES-R score was 18.47 (S.D. = 11.69) which indicated that the study population experienced mild psychological stress but not to the extent of acute stress reaction syndrome. The perceived dangerous PSI level and number of physical symptoms were significantly associated with the mean intrusion score, mean hyper-arousal score, total mean IES-R score and total IES-R score (p < 0.05).
  
  
  CONCLUSIONS
  Our findings suggest that a haze crisis is associated with acute physical symptoms and mild psychological stress. The number of physical symptoms and the perceived dangerous PSI values are important factors associated with psychological stress.
authors.forename: Roger C
authors.initials: RC
authors.lastname: Ho
authors.affiliation: Southeast Asian Haze Research Consortium, Jinan, China. melvynzhangweibin@gmail.com.
authors.forename: Melvyn W
authors.initials: MW
authors.lastname: Zhang
authors.forename: Cyrus S
authors.initials: CS
authors.lastname: Ho
authors.forename: Fang
authors.initials: F
authors.lastname: Pan
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Lu
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Sharma
mesh_terms: D000208:Acute Disease; D000328:Adult; D000393:Air Pollutants / Q000633:toxicity*; D000397:Air Pollution / Q000706:statistics & numerical data*; D002248:Carbon Monoxide / Q000633:toxicity*; D015984:Causality; D015897:Comorbidity; D005260:Female; D005390:Fires; D006261:Headache / Q000453:epidemiology; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012140:Respiratory Tract Diseases / Q000453:epidemiology* / Q000209:etiology; D013315:Stress, Psychological / Q000453:epidemiology* / Q000209:etiology
chemical_list: D000393:Air Pollutants; D002248:Carbon Monoxide