Summary. Introduction: The problem of strong offensive odor produced by operation of sewage treatment plants is known to be quite pressing and common. It is now related to the fact that urban development made these plants, once built on the outskirts, appear within city boundaries, near summerhouses and cottage villages. Malodor is perceived by local population as a sign of poor ambient air quality that evokes negative emotions and unfavorable reflex responses and makes most people feel unwell. Materials and methods: We analyzed sewage sludge from wastewater treatment plants for the whole range of chemicals that can migrate into ambient air and identified priority odor-generating pollutants. Sewage sludge testing was carried out in simulated conditions using advanced high-precision analytical techniques such as mass-spectrometry, spectrophotometry, fluorimetry, gas chromatography, and high performance liquid chromatography. Conclusions: Based on study results, we developed a list of chemicals subject to laboratory monitoring and substantiated the expediency of their detection in the presence of public complaints of offensive odors coming from sewage treatment plants.

Introduction: Owing to the rapid development of digital technologies, most people nowadays are working indoors while using no machinery or equipment and being unexposed to volatile industrial chemicals. Yet, people staying inside for too long often complain of poor indoor air quality and microclimate. Our objective was to study air pollutants in a simulation experiment with continuous human occupancy inside unventilated confined spaces. Materials and methods: Up-to-date sensitive analytical techniques, such as photoionization, laser nephelometry, gas-phase chemiluminescence, spectrophotometry, high-performance liquid chromatography with diode array detection (HPLCDAD) and gas chromatography–mass spectrometry (GC-MS), were used to determine indoor air pollutants. Results: We compared changes in airborne concentrations of nitrogen oxides, prop-2-enenitrile, acetaldehyde, benzene, but-2-enal, airborne particulate matter (PM2,5 and PM10), methylbenzene, 2-methylbuta-1,3-diene, formaldehyde, prop-2-en-1-al, carbon oxide and dioxide following 1.5, 3.0, and 4.5 hours of stay of volunteers in a 15.9 m2 room (4.0 m2 per person; a 2.55 m ceiling height) against background levels. The established human occupancy-related priority pollutants included acetaldehyde, formaldehyde, prop-2-en-1-al, and carbon dioxide. Laboratory testing showed the presence of 83 volatile and semivolatile organic chemicals in the unventilated room, among which aromatic hydrocarbons, esters and aldehydes prevailed. Conclusion: Our findings could be useful for designing ventilation systems in confined spaces and optimizing the workbreak schedule during the working hours.