The aim of this study was to evaluate the impact of a sewage treatment plant on the occurrence of gastrointestinal symptoms among the local residents. A survey was conducted on two populations: one from the vicinity of the sewage treatment plant (the exposed group: 586 people), and the other from outside the impact area of the plant (the control group: 502 people). The research area was divided into distance zones from the plant (A, B, C). The questionnaire included questions about the occurrence of gastrointestinal disorders. Compared with the control group, the local residents reported more often: nausea, vomiting, and frequent diarrhea. Occurrences of gastrointestinal disorders were associated with air pollution by pathogenic staphylococci (OR~7) and odours (OR = 7.34; Cl 3.43-15.72) emitted by the plant, and also living in zone A vs. zone C (OR = 3.47; CI 1.00-12.07), use of a gas cooker in houses (OR = 2.21; CI 1.03-4.70), and the age of the respondents (0.98; CI 0.96-1.00). The study showed that as distance from the plant increased, the incidence of reported gastrointestinal disorders declined. Living in the vicinity of a sewage treatment plant favours the occurrence of gastrointestinal symptoms among the local residents.