title: Perceived annoyance from environmental odors and association with atmospheric ammonia levels in non-urban residential communities: a cross-sectional study.
abstract: OBJECTIVE
  Odor exposure is an environmental stressor that is responsible of many citizens complains about air pollution in non-urban areas. However, information about the exposure-response relation is scarce. One of the main challenges is to identify a measurable compound that can be related with odor annoyance responses. We investigated the association between regional and temporal variation of ammonia (NH3) concentrations in five Danish non-urban regions and environmental odor annoyance as perceived by the local residents.
  
  
  METHODS
  A cross-sectional study where NH3 concentration was obtained from the national air quality monitoring program and from emission-dispersion modelling, and odor pollution perception from questionnaires. The exposure-response model was a sigmoid model. Linear regression analyses were used to estimate the model constants after equation transformations. The model was validated using leave-one-out cross validation (LOOCV) statistical method.
  
  
  RESULTS
  About 45% of the respondents were annoyed by odor pollution at their residential areas. The perceived odor was characterized by all respondents as animal waste odor. The exposure-annoyance sigmoid model showed that the prevalence of odor annoyance was significantly associated with NH3 concentrations (measured and estimated) at the local air quality monitoring stations (p < 0.01,R2 = 0.99; and p < 0.05,R2 = 0.93; respectively). Prediction errors were below 5.1% and 20% respectively. The seasonal pattern of odor perception was associated with the seasonal variation in NH3 concentrations (p < 0.001, adjusted R2 = 0.68).
  
  
  CONCLUSIONS
  The results suggest that atmospheric NH3 levels at local air quality stations could be used as indicators of prevalence of odor annoyance in non-urban residential communities.
authors.affiliation: Inst, Chemical Eng,, Biotechnology and Environmental Tech, Faculty of Engineering, University of Southern Denmark, Odense, Denmark. vbv@kbm.sdu.dk
authors.forename: Victoria
authors.initials: V
authors.lastname: Blanes-Vidal
authors.forename: Esmaeil S
authors.initials: ES
authors.lastname: Nadimi
authors.forename: Thomas
authors.initials: T
authors.lastname: Ellermann
authors.forename: Helle V
authors.initials: HV
authors.lastname: Andersen
authors.forename: Per
authors.initials: P
authors.lastname: Løfstrøm
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000641:Ammonia / Q000032:analysis*; D003430:Cross-Sectional Studies; D003718:Denmark; D004781:Environmental Exposure; D004784:Environmental Monitoring; D016014:Linear Models; D009812:Odorants / Q000032:analysis*; D012111:Residence Characteristics; D012424:Rural Population; D012621:Seasons; D011795:Surveys and Questionnaires
chemical_list: D000393:Air Pollutants; D000641:Ammonia