Introduction:
The presence of hydrogen sulfide (H2S) in areas of copper mines’ ventilation shafts’ impact is periodically perceived by inhabitants as a characteristic odor. The olfactory detection threshold for H2S is 0.007 mg/m³. Hydrogen sulfide in concentrations >20 mg/m³ irritates conjunctiva and mucous membranes. At higher concentrations, it blocks intracellular respiratory enzymes and acts as a neurotoxin.

Aim:
The aim of the study was to assess the effects of hydrogen sulphide in a group of exposed inhabitants living in the copper mine area, in particular on olfactory function, the most sensitive to toxic H2S action.

Material and Methods:
In 2013–2015, three groups were examined: 165 inhabitants of the copper mine area aged 48.2±17.9 (study group); 124 inhabitants non-exposed to H2S aged 52.4±13.5 (control group) and 46 miners of the copper mine, occupationally exposed to H2S. Medical surveys, physical exams, blood tests for H2S concentration and basic biochemical parameters, and smell examinations using the Sniffin Sticks – Screening kit were carried out.

Results:
Residents from the study group most frequently reported the discomfort associated with the unpleasant odor, as well as burning, itching and watery eyes, a runny nose and scratching in the throat, in the absence of changes on physical examination. In 60% of examined residents, normosmia was diagnosed, 34% had hyposmia and 6% had anosmia. The results were comparable to those obtained in the control group. In the group of miners, no significant olfactory disturbances were found. In all studied groups, the most common changes in the health status were lipid pattern disturbances and hypertension.

Conclusions:
In our study, no toxic effects of periodic H2S exposure on the olfactory organ were found, and the main consequence of H2S action was the discomfort associated with the unpleasant odor.