Odour Annoyance Research Articles

Influence of uncomfortable environmental conditions on odor detection thresholds for n-butanol determined with a dynamic dilution olfactometer and in room air

Odor guide values (OGV) are used when a person is exposed to an odor in a room and complains about odor annoyance. OGV are derived from odor detection thresholds (ODT) measured under standard environmental conditions. The study question was whether uncomfortable environmental conditions alter odor perception and should therefore be considered when applying OGV. ODT for n-butanol were determined with an olfactometer and in room air. Twenty healthy, non-smoking volunteers (10 women/10 men, 19–50 years) were selected and trained compliant with the European Standard for Olfactometry EN 13725:2022. Standard conditions were an average temperature between 22 °C and 23 °C, warm light (2800 Kelvin), quiet fan noise (45 dB), 415 ppm carbon dioxide (CO2), and relative humidity between 34 % and 42 %. On each test day, one of five conditions was examined: high temperature (26°C), cold light (6500 Kelvin), traffic noise (70 dB with peaks up to 85 dB), 1000 ppm CO2 and 4000 ppm CO2. Comparability of log-transformed ODT values was assessed by Bland-Altman plot analysis. None of the five conditions systematically affected ODT, either when measured with an olfactometer or in room air. Compared to standard conditions (Limits of Agreement (± LoA) 1.03), the variability of ODT was higher at high temperature (± LoA 1.70) and traffic noise (± LoA 1.45), but not at cold light (± LoA 1.02), 1000 ppm CO2 (± LoA 0.87) or 4000 ppm CO2 (± LoA 0.93). The results show that OGV can be used in uncomfortable environmental conditions. However, because ODT were lower or higher in a few subjects at high temperatures and traffic noise, individual occupant’s perception of temperature and noise should always be considered when applying the OGV concept. Furthermore, the results confirm that the experimental determination of ODT should be performed under controlled and standardized environmental conditions.

Comparison of odor detection thresholds for n-butanol and benzaldehyde determined with a dynamic dilution olfactometer and in room air

The German Committee on Indoor Air Guide Values (AIR) has developed a concept of odor guide values (OGV) based on odor detection thresholds (ODT) to assess the plausibility of complaints about odor annoyance. ODT were determined directly at the nose with a dynamic dilution olfactometer. However, OGV will be used when a person is exposed to the odor in a room. This study aimed to assess the comparability of ODT determined with a dynamic dilution olfactometer according to the European Standard for Olfactometry EN 13725:2022 with ODT determined in room air under standardized conditions as described in the International Standard ISO 16000–30. ODT for n-butanol and benzaldehyde were determined by each method in 20 healthy, non-smoking volunteers (10 women/10 men, 19–50 years). Participants were screened for normal olfactory function and selected and trained in odor assessment compliant with EN 13725:2022. Comparability of log-transformed ODT values was assessed using Bland-Altman plot analysis. ODT values determined in room air were lower than by dynamic olfactometry. The bias for n-butanol was – 0.48 lg(ppb) (limits of agreement (LoA): – 1.13, + 0.18) and for benzaldehyde – 0.25 lg(ppb) (LoA: – 0.76, + 0.26). Measured differences were considered practically negligible for benzaldehyde, but not for n-butanol. Surface adsorption effects in the dilution system of the olfactometer and differences in the test procedures are discussed as possible causes for this discrepancy. Concluding, ODT determined with an olfactometer directly at the nose are suitable for deriving OGV and can be applied when a person is exposed to odors in room air.

Noise by neighbours: an update

RIVM conducts an annual survey of residents' perceptions of their living environment. This includes monitoring data on residents' perception of noise, odours and vibrations. Between 2019 and 2022, more than 8,000 Dutch residents aged 16 and over took part in these surveys. Online questionnaires presented people with a range of possible sources of annoyance and sleep disturbance in their homes and neighbourhoods. Road traffic noise is a major source of severe annoyance and sleep disturbance. Mopeds and motorcycles in particular cause severe noise annoyance. Compared to 2016, more people experience severe annoyance from the sound of vans. Road traffic also causes annoyance through vibrations. Neighbours are the second most important source of noise annoyance and the most important source of severe odour annoyance in the Netherlands. The latter is mainly due to odours from fireplaces, fire pits and barbecues. Neighbours' activities also cause severe annoyance due to vibrations.

Impacts of citizen science on trust between stakeholders and trust in science in a polarized context

ABSTRACT Air pollution and odour annoyance caused by livestock farming often leads to tension and distrust between livestock farmers and non-farming residents in agricultural areas in the Netherlands. In this study, we conducted a citizen science project to measure air quality and odour annoyance in collaboration with farmers, non-farming residents, and the municipality. The aim was to explore whether measuring together through citizen science influenced (1) mutual trust between stakeholders, and (2) their trust in the scientific process and outcomes of this project. We conducted semi-structured interviews with participants before and after participating in the project. Results indicated that measuring together did not improve trust between farmers and their neighbours. However, non-farming residents did express more trust in the municipality and perceived their interests were more fairly taken into account. Moreover, all participants expressed trust in the scientific process and outcomes regarding their ‘own’ measurements; contrasting the distrust they expressed in the ‘official’ governmental data. Control and transparency due to their own involvement, involvement of an independent scientific institute and positive interactions with the scientists’ contributed to this trust. These results highlight the need for further research on the potential impact of citizen science projects on trust in different contexts.

Environmental complaint insights through text mining based on the driver, pressure, state, impact, and response (DPSIR) framework: Evidence from an Italian environmental agency

Individuals, local communities, environmental associations, private organizations, and public representatives and bodies may all be aggrieved by environmental problems concerning poor air quality, illegal waste disposal, water contamination, and general pollution. Environmental complaints represent the expressions of dissatisfaction with these issues. As the time-consuming of managing a large number of complaints, text mining may be useful for automatically extracting information on stakeholder priorities and concerns. The paper used text mining and semantic network analysis to crawl relevant keywords about environmental complaints from two online complaint submission systems: online claim submission system of Regional Agency for Prevention, Environment and Energy (Arpae) (“Contact Arpae”); and Arpae's internal platform for environmental pollution (“Environmental incident reporting portal”) in the Emilia-Romagna Region, Italy. We evaluated the total of 2477 records and classified this information based on the claim topic (air pollution, water pollution, noise pollution, waste, odor, soil, weather-climate, sea-coast, and electromagnetic radiation) and geographical distribution. Then, this paper used natural language processing to extract keywords from the dataset, and classified keywords ranking higher in Term Frequency-Inverse Document Frequency (TF-IDF) based on the driver, pressure, state, impact, and response (DPSIR) framework. This study provided a systemic approach to understanding the interaction between people and environment in different geographical contexts and builds sustainable and healthy communities. The results showed that most complaints are from the public and associated with air pollution and odor. Factories (particularly foundries and ceramic industries) and farms are identified as the drivers of environmental issues. Citizen believed that environmental issues mainly affect human well-being. Moreover, the keywords of “odor”, “report”, “request”, “presence”, “municipality”, and “hours” were the most influential and meaningful concepts, as demonstrated by their high degree and betweenness centrality values. Keywords connecting odor (classified as impacts) and air pollution (classified as state) were the most important (such as “odor-burnt plastic” and “odor-acrid”). Complainants perceived odor annoyance as a primary environmental concern, possibly related to two main drivers: “odor-factory” and “odors-farms”. The proposed approach has several theoretical and practical implications: text mining may quickly and efficiently address citizen needs, providing the basis toward automating (even partially) the complaint process; and the DPSIR framework might support the planning and organization of information and the identification of stakeholder concerns and priorities, as well as metrics and indicators for their assessment. Therefore, integration of the DPSIR framework with the text mining of environmental complaints might generate a comprehensive environmental knowledge base as a prerequisite for a wider exploitation of analysis to support decision-making processes and environmental management activities.

Research on odor characteristics of typical odorants of railway vehicle products.

Odor annoyance was a kind of environmental air pollution. Compared to other indoor environments, vehicle interior materials were not well studied. Especially, there had been little research on odor character of the railway vehicles. This study applied the OAV method to identify the key odorants of railway vehicle materials and discussed the characteristics of these odorants through Weber Fechner law and a dual variable method. The result showed that for single odorant, Weber Fechner law can be used to estimate the perceived intensity of an odor gas sample at different concentration levels. The odorant with smaller slope had significant tolerance to human. For the mixtures of odorants, the overall intensity of the mixture is generally dominated by the strongest odor intensity of the individual substance in the mixture, and positive interaction effect can be observed in mixtures whose intensities had little difference. But there was a kind of odorants, such as methacrylate, in which a very small variation in the concentration of mixtures can affect its odor intensity largely. Meanwhile, the odor intensity modification coefficient was an effective way to identify and evaluate odor interaction effect. The interaction potential of the studied odorants from strong to weak was methacrylate, dibutyl-amine, nonanal, 2-ethyl hexanol. The odor interaction potential and odor nature should be paying much attention in the improvement of odor in railway vehicle product.

Farmers and Local Residents Collaborate: Application of a Participatory Citizen Science Approach to Characterising Air Quality in a Rural Area in The Netherlands.

In rural areas, livestock farming is a source of environmental concern. We describe a citizen science (CS) project in Venray, the Netherlands, where air quality was measured at livestock farms and surrounding residential premises. We used low-cost methods to measure air quality components and facilitated a dialogue between stakeholders about the results and solutions for cleaner air. PM2.5 and PM10 were measured using Nova Fitness SDS011 sensors, nitrogen dioxide (NO2) and ammonia (NH3) using Palmes tubes and odour annoyance was reported. Particulate Matter (PM) concentrations were higher close to layer farms, but elevated concentrations were limited at other farms and residential locations. NO2 concentrations were elevated near busy roads, and higher NH3 values were measured near livestock farms. Reporting of odour annoyance was limited, yet during the dialogue residents indicated that this was their largest concern. While both farmers and residents agreed with the general conclusions, they still preferred opposing measures. We conclude that characterisation of air quality using low-cost methods is possible, but expert guidance is needed. Moreover, education, commitment of participants and involvement of independent parties are crucial to ensuring a productive dialogue between stakeholders. The insights gained by participants and resulting dialogue were the greatest benefits of this CS approach.

Smart instrumental Odour Monitoring Station for the efficient odour emission management and control in wastewater treatment plants

Odour emission assessment in wastewater treatment plants (WWTP) is a key aspect that needs to be improved in the plant management to avoid complaints and guarantee a sustainable environment. The research presents a smart instrumental odour monitoring station (SiOMS) composed of an advanced instrumental odour monitoring system (IOMS) integrated with other measurement units, for the continuous characterization and measurement of the odour emissions, with the aim of managing the potential odour annoyance causes in real time, in order to avoid negative effects. The application and on-site validation procedure of the trained IOMS is discussed. Experimental studies have been conducted at a large-scale WWTP. Fingerprint analysis has been applied to analyze and identify the principal gaseous compounds responsible for the odour annoyance. The artificial neural network has been adopted to elaborate and dynamically update the odour monitoring classification and quantification models (OMMs) of the IOMS. The results highlight the usefulness of a real-time measurement and control system to provide continuous and different information to the plant operators, thus allowing the identification of the odour sources and the most appropriate mitigation actions to be implemented. The paper provides important information for WWTP operators, as well as for the regulating bodies, authorities, manufacturers and end-users of odour monitoring systems involved in environmental odour impact management.

Methodology for assessment the impact of environmental odours on the population according to questionnaire surveys (literature review)

This article contains the review of methodological approaches to assessment of the perception by the population odours from industrial and other sources, and studying the relationship between the perception of odours with the both the health status and quality of resident’s life, the degree of odour annoyance, using questionnaires. The literature search was carried out using Pubmed, Scopus, Web of Science, MedLine, Global Health, RSCI databases. The long-term practice of surveys of the population living in areas, where sources of emissions of odourous substances are located, has shown annoyance with odours to be a complex reaction, including emotional, behavioral, and somatic aspects. In addition to the direct impact of the odour, it is important to take into account contextual and personal factors that can weaken or strengthen the annoyance. Personal factors include the socio-demographic characteristics of the respondents, “environmental worry”, ways of responding to the situation and the subjective assessment of their own health. Contextual factors include the socio-economic conditions of the population and other indicators of the environmental state. These factors form the blocks included in the model of the relationship between odour impact, odour perception and odour annoyance, which is the basis of a standard questionnaire for a population survey. The questionnaire consists of basic and additional questions combined in several modules. The questions of the main module, which are obligatory and asked in all cases, devoted to the living conditions of the respondents, environmental factors (for example, noise and odours) that, in their opinion, can cause annoyance, have a negative impact on health. The questions of the additional modules (“Health”, “Behavioral changes”, “Environmental worry”) are asked depending on the context and specific objectives of the study. Using this methodology, numerous studies have been conducted abroad, which have shown the presence of correlations between the annoyance of odours, the occurrence of stress and the appearance of symptoms of various diseases. In different countries, the proportion of residents who are “significantly annoyed” by odours, is a criterion for authorities and enterprises to make certain management decisions to reduce emissions. The use of questionnaires can be implemented in the Russian Federation, where enterprises being sources of odours are located, in particular, if there is a problem with odours in the atmospheric air, while complying with the current sanitary legislation.

Odor perception and symptoms during acrolein exposure in individuals with and without building-related symptoms

Building-related symptoms (BRS) is a significant work-related and public health problem, characterized by non-specific symptoms occurring in a particular building. The cause of BRS is unknown, but certain reactive compounds are suggested risk factors. The aim of this controlled exposure study was to investigate whether BRS cases report more odor annoyance and symptoms and show altered autonomous nervous system (ANS) response during exposure to the reactive aldehyde, acrolein in comparison with referents. Individuals with BRS (n = 18) and referents (n = 14) took part in two exposure sessions (80 min). One session contained heptane alone, and the other heptane and acrolein. Perceived odor annoyance; eye, nose, and throat symptoms; and ANS response were measured continuously. BRS cases did not experience more odor annoyance; eye, nose, and throat symptoms; or altered ANS response in comparison with referents during the exposures. Supplementary analyses revealed that BRS cases that also reported chemical intolerance perceived more symptoms than referents during acrolein exposure. Acrolein exposure at a concentration below previously reported sensory irritation detection thresholds is perceived as more irritating by a subgroup of BRS individuals compared with referents. The results of this study indicate that a subset of individuals with building related symptoms (BRS) has a lowered sensory irritation threshold towards acrolein exposure. Future guidelines on chemical exposures to acrolein should take time and individual sensitivity into account.

Optimization of activated sludge recycling and oxidized ammonium recycling as odour control strategies in wastewater treatment plants

New odour prevention strategies in wastewater treatment facilities need to be investigated to find effective and low-cost technologies for the control of malodorous emissions. In this study, the potential of activated sludge (AS) and oxidized nitrogen (N-NOx) recycling as an environmentally-friendly and cost-effective strategy for the prevention and minimization of odour nuisance during wastewater treatment was evaluated and optimized using H2S, acetic acid and α-pinene as model odorants in 2.1 L gas tight bottles. This approach uses by-products from wastewater treatment to mitigate odour annoyance. Preliminary abiotic tests showed headspace concentration losses of 25% for H2S and α-pinene, and 7% for acetic acid due to odorant adsorption in 4 h. The experiments carried out at different concentrations of AS (0, 10, 25, 50, 100 mg VSS/L) and oxidized nitrogen (1.5, 5, 7.5 and 10 mg N-NOx/L) revealed an effective H2S removal at 7.5–10 mg N-NOx/L and 50–100 mg VSS/L. Interestingly, NO3− was more effective than NO2− as electron acceptor during the biodegradation of H2S regardless of the AS concentration and N-NOx concentrations. In the presence of dissolved H2S and AS concentrations of 50–100 mg VSS/L, acetic acid was partially metabolized by microorganisms at the end of experiment (from 27 to 23 ppmv in 4.5 h), while α-pinene concentrations experienced a similar gradual decrease than in the abiotic tests. Finally, the assays carried out at concentrations ≥5 mg NO3−/L and 25 mg VSS/L showed a reduction of NO3− to NO2− correlated with the biological oxidation of H2S, which suggested the need to control NO3− supply under sulphur limiting conditions to prevent toxicity problems during wastewater treatment.

Cannabis Cultivation Facilities: A Review of Their Air Quality Impacts from the Occupational to Community Scale.

This review addresses knowledge gaps in cannabis cultivation facility (CCF) air emissions by synthesizing the peer-reviewed and gray literature. Focus areas include compounds emitted, air quality indoors and outdoors, odor assessment, and the potential health effects of emitted compounds. Studies suggest that β-myrcene is a tracer candidate for CCF biogenic volatile organic compounds (BVOCs). Furthermore, β-myrcene, d-limonene, terpinolene, and α-pinene are often reported in air samples collected in and around CCF facilities. The BVOC emission strength per dry weight of plant is higher than most conventional agriculture crops. Nevertheless, reported total CCF BVOC emissions are lower compared with VOCs from other industries. Common descriptors of odors coming from CCFs include "skunky", "herbal", and "pungent". However, there are few peer-reviewed studies addressing the odor impacts of CCFs outdoors. Atmospheric modeling has been limited to back trajectory models of tracers and ozone impact assessment. Health effects of CCFs are mostly related to odor annoyance or occupational hazards. We identify 16 opportunities for future studies, including an emissions database by strain and stage of life (growing cycle) and odor-related setback guidelines. Exploration and implementation of key suggestions presented in this work may help regulators and the industry reduce the environmental footprint of CCF facilities.

Performance of wet scrubbers to remove VOCs from rubber emissions

Poor performance of wet scrubbers in rubber processing plants due to breakthrough of specific volatile organic compounds (VOCs) causes odour impact events. The performance of wet scrubbers in the rubber drying process to remove VOCs was investigated in order to determine the responsible odorants. VOC emissions originating at the inlet and outlet of wet scrubbers were quantified using gas chromatography-mass spectrometry/olfactometry (GC-MS/O). Critical VOCs were identified alongside seasonal and daily variations of those VOCs. Altogether, 80 VOCs were detected in rubber emissions with 16 classified as critical VOCs based on their chemical concentration, high odour activity value (OAV) and unpleasant odour. Volatile fatty acids (VFAs) were the dominant VOCs with seasonal variations affecting emission composition. Results demonstrated the ineffectiveness of the wet scrubbers to mitigate odorous VOCs whereas the removal of some VOCs could be improved based on their polarity and solubility. It was found that there is a correlation between the wet scrubber performance and VFAs concentration in the emissions. The findings demonstrated that combining quantitative and sensory analyses improved accuracy in identifying odorous VOCs, which can cause odour annoyance from rubber processing. A VOC identification framework was proposed using both analyses approaches.

Full-Scale Odor Abatement Technologies in Wastewater Treatment Plants (WWTPs): A Review

The release of air pollutants from the operation of wastewater treatment plants (WWTPs) is often a cause of odor annoyance for the people living in the surrounding area. Odors have been indeed recently classified as atmospheric pollutants and are the main cause of complaints to local authorities. In this context, the implementation of effective treatment solutions is of key importance for urban water cycle management. This work presents a critical review of the state of the art of odor treatment technologies (OTTs) applied in full-scale WWTPs to address this issue. An overview of these technologies is given by discussing their strengths and weaknesses. A sensitivity analysis is presented, by considering land requirements, operational parameters and efficiencies, based on data of full-scale applications. The investment and operating costs have been reviewed with reference to the different OTTs. Biofilters and biotrickling filters represent the two most applied technologies for odor abatement at full-scale plants, due to lower costs and high removal efficiencies. An analysis of the odors emitted by the different wastewater treatment units is reported, with the aim of identifying the principal odor sources. Innovative and sustainable technologies are also presented and discussed, evaluating their potential for full-scale applicability.

The relative effects of self-reported noise and odour annoyance on psychological distress: Different effects across sociodemographic groups?

In earlier research, both higher levels of noise and odour annoyance have been associated with decreased mental health. Presumably, these perceptions can trigger feelings of threat and stress reactions and in turn evoke psychological distress. There are two important lacunas in the research on this topic: most studies only consider either noise or odour annoyance and not their relative effect on psychological distress and there is scarce evidence about whether different sociodemographic groups experience more psychological distress due to noise and odour annoyance. Starting from the diversity in the available coping resources and in their daily life patterns, we distinguish gender, age and educational level as relevant sociodemographic variables. Using data from the Health Monitor (n = 25236) in Noord-Brabant, we found using Ordinary Least Squares Regression that individuals that reported higher levels of noise and odour annoyance reported higher levels of psychological distress. Furthermore, the effect of noise annoyance was relatively stronger compared to that of odour annoyance. Regarding the interaction effects, we found that younger adults' psychological distress was more strongly affected by noise annoyance compared to older adults, but not by odour annoyance. The psychological distress of individuals with no or primary education was more strongly affected by both noise and odour annoyance compared those with tertiary education, but not when compared to those who completed lower or higher secondary education. Contrary to our expectations, we did not find different effects between men and women. Though the evidence for the interactions was mixed, classic health inequalities along age and education lines are reinforced when considering the relationship between noise and odour annoyance and psychological distress.

Perception of the Home Environment. The 2019 Study

RIVM conducted a questionnaire study into residents' perception of the living environment. This includes monitoring data on residents perception of sounds, vibrations, odours, and safety risks in the neighbourhood. In 2019, 2259 residents of the Netherlands aged 16 years and older participated in this survey. The 2019 data show that the degree of satisfaction with the home environment was fairly high and the same as it was during the previous survey in 2016. Road traffic is an important source of severe annoyance (10.4%) and severe sleep disturbance (5,9%). Mopeds and motorbikes in particular cause severe noise annoyance (10.6%). Compared to 2016, more people experience severe annoyance from the sound of vans. Road traffic also causes nuisance due to the vibrations that it causes (3.9%). Neighbours are a source of noise annoyance (9.0%) and the most important source of severe odour annoyance. The latter primarily involves odours from fireplaces (5.3%), fire pits, and barbecues (5.0%). Activities by neighbours also cause severe annoyance due to vibrations. It also turns out that people living in the vicinity of a 'higher-risk activity', such as heavy industry, are more frequently (severely) concerned about their own safety. Results of the 2020 Study will presented as well.

Improving the Impact of Odour Nuisance in Thessaloniki: a Stakeholder Engagement Approach

Nowadays, it is widely acknowledged that the problem of odour pollution is extremely important and requires immediate action. The problem is high also at European Union’s political agenda, which highlights the issue of odours at European level and seeks to apply innovative tools, such as direct citizen participation and education, modelling and mapping tools, in order to tackle the problem and propose a related legislative framework and establish rules for controlling and reducing odour disturbances.In this context, a key feature is the creation of an exchange of views to inform and understand the nature of odour incidents, with the joint involvement of authorities, citizens, universities and odour producers, with the aim of exploring mutually acceptable solutions.To the best of our knowledge, there are very few studies that deal with the issue of odour nuisance, even less that focus on the western part of the city of Thessaloniki. The treatment of odour annoyance associated with industrial and other activities in the area of Dendropotamos, Menemeni, Kalochori is considered as an appropriate case for the implementation of this study. The combination of the odour issue and at the same time the environmental impact on the area make this case extremely interesting.The current study aims at proposing a methodology that is based on Citizen Science and stakeholder engagement, which provides for active participation in scientific endeavours that generate new knowledge or perceptions. The proposed approach is part of the methodology initiated by the European Commission Horizon 2020 Project D-NOSES. The main objective of the study is to understand the problem and through stakeholder engagement and the active involvement of as many parties as possible, who are affected by the problem, to improve the impact of odours in the area. Training seminars, bilateral interviews and discussions assisted in developing a common understanding and goals, while an electronic application, the Odour Collect, developed for this purpose can report 'real-time' odour incidents and give them qualitative features. The results from the case study of Thessaloniki are presented in this paper and could further assist decision makers and key player to propose measures for improving the current situation.Key words: Odour Nuisance; Odour; Citizen Science; Stakeholder Engagement; Stakeholders Consultation; Participatory Approach; Statistical Analysis; Thessal

Outcomes of a Citizen Science Methodology and Traditional Odour Impact Evaluation Techniques Applied in a Chilean Pilot Study

The EU Horizon 2020 call ‘’Science with & for Society’’ funded the D-NOSES project (Distributed Network for Odour Sensing, Empowerment and Sustainability), which aims to develop a methodology based on participatory strategies and collaboration among different stakeholders using an extreme citizen science approach. This paper presents the findings of this approach applied to a Chilean case study concerning a small community impacted by a municipal wastewater treatment plant. Results of odour observations gathered by citizens during a three-month period are compared with the traditional odour impact evaluation techniques such as field inspections. An adapted odour annoyance index showed a better accuracy for each assessment square compared to the odour impact characteristics. It also points out challenges of citizen participation and opportunities of combining both approaches.

The effects of paints and moisture content on the indoor air emissions from pinewood (Pinus sylvestris) boards.

The emissions of volatile organic compounds (VOCs) from building materials may significantly contribute to indoor air pollution, and VOCs have been associated with odor annoyance and adverse health effects. Wood materials together with coatings are commonly used indoors for furniture and large surfaces such as walls, floors, and ceilings. This leads to high surface-to-volume ratios, and therefore, these materials may participate remarkably to the VOC levels of indoor environment. We studied emissions of VOCs and carbonyl compounds from pinewood (Pinus sylvestris) boards of 10% and 16% moisture contents (MC) with three paints using small-scale test chambers (27L). The emissions from uncoated pinewood and paints (on a glass substrate) were tested as references. The 28-day experiment showed that the VOC emissions from uncoated pinewood were lower from sample with 16% MC. Painted pinewood samples showed lower emissions compared to paints on glass substrate. Additionally, paints on 16% MC pinewood exhibited lower emissions than on drier 10% MC wood. The emissions from painted pinewood samples were dominated by paint-based compounds, but the share of wood-based compounds increased over time. However, we noticed differences between the paints, and wood-based emissions were clearly higher with the most permeable paint.

Determination of Dose–Response Relationship to Derive Odor Impact Criteria for a Wastewater Treatment Plant

Municipal wastewater treatment plants (WWTPs) inside cities have been the major complained sources of odor pollution in China, whereas there is little knowledge about the dose–response relationship to describe the resident complaints caused by odor exposure. This study explored a dose–response relationship between the modelled exposure and the annoyance surveyed by questionnaires. Firstly, the time series of odor concentrations were preliminarily simulated by a dispersion model. Secondly, the perception-related odor exposures were further calculated by combining with the peak to mean factors (constant value 4 (Germany) and 2.3 (Italy)), different time periods of “a whole year”, “summer”, and “nighttime of summer”, and two approaches of odor impact criterion (OIC) (“odor-hour” and “odor concentration”). Thirdly, binomial logistic regression models were used to compare kinds of perception-related odor exposures and odor annoyance by odds ratio, goodness of fit and predictive ability. All perception-related odor exposures were positively associated with odor annoyance. The best goodness of fit was found when using “nighttime of summer” in predicting odor-annoyance responses, which highlights the importance of the time of the day and the time of the year weighting. The best predictive performance for odor perception was determined when the OIC was 4 ou/m3 at the 99th percentile for the odor exposure over time periods of nighttime of summer. The study of dose–response relationship could be useful for the odor management and control of WWTP to maximize the satisfaction of air quality for the residents inside city.