title: Short-term effects of subchronic low-level hydrogen sulfide exposure on oil field workers.
abstract: OBJECTIVE
  To investigate the short-term effects of low-level hydrogen sulfide (H2S) exposure on oil field workers.
  
  
  METHODS
  Observational study included 34 patients who work at an oil field. All patients were males with age range of 22-60 years (mean 37 years). The data were collected by systematic questionnaire about symptoms. The inclusion criteria of patients were symptoms related to inhalation of H2S gas in the oil field. The complaints should be frequent and relapsed after each gas exposure and disappeared when there was no gas exposure. Exclusion criteria were the symptoms which experienced with or without H2S exposure. The presence of H2S gas was confirmed by valid gas detector devices.
  
  
  RESULTS
  The most frequent presenting symptom was nasal bleeding. It was revealed in 18 patients (52.9%). This followed by pharyngeal bleeding, gum bleeding, and bloody saliva (mouth bleeding) which were encountered in five cases for each complaint (14.7%). Other less frequent presenting symptoms were tongue bleeding, bloody sputum, headache, abdominal colic, pharyngeal soreness, fatigue, and sleepiness.
  
  
  CONCLUSIONS
  Nasal mucosa was the most vulnerable part to H2S effect. Inhalation of H2S produced upper respiratory tract epithelial damage that led to bleeding from nose, pharynx, gum, tongue, trachea, and bronchi. There were no complaints of asthmatic attack upon exposure to low level of H2S. Sunlight had a significant role in reduction of ambient air H2S level.
authors.affiliation: College of Medicine, University of Basrah, Basrah, Iraq, haideramousa@hotmail.com.
authors.forename: Haider Abdul-Lateef
authors.initials: HA
authors.lastname: Mousa
mesh_terms: D000328:Adult; D004784:Environmental Monitoring / Q000379:methods; D006470:Hemorrhage / Q000139:chemically induced* / Q000453:epidemiology*; D006801:Humans; D006862:Hydrogen Sulfide / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000473:pathology; D009784:Occupational Diseases / Q000139:chemically induced* / Q000453:epidemiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D061329:Oil and Gas Fields; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D006862:Hydrogen Sulfide