The indoor air quality (IAQ) in office-like environments is an issue of increasing focus because office workers provide services of high relevance. The office workers, which account for most of the labor force in many countries, are occupationally exposed to biological, chemical, physical, ergonomic, and psycho-logical/social loads with a potentially high and diversified impact on comfort [1
], work-related health problems [2
], sickness absence [3
], and risk of deteriorated work performance [4
]. Another issue is an ageing workforce, later retirement, and the general trend (in Europe) that the workforce in public offices is being reduced due to economic constraints. In this context, effects of IAQ on health, well-being, and work-performance have been reported in office-like environments in recent decades (e.g., [5
Modern offices are built with new materials, equipment, and the use of a variety of cleaning, consumer, and personal care products; their emission of chemicals and particles reflects IAQ together with the incoming outdoor air. New energy saving strategies, like lightning, heating, cooling, and ventilation, also impact the perception of IAQ. Furthermore, pollutants that are emitted from office equipment—e.g., laser printer emissions (ozone, primary VOCs, and particles)—and secondary VOCs derived from reactive indoor air chemistry may be of concern [8
The EnVIE project prioritized the following diseases caused or exacerbated by poor IAQ: allergic and asthma symptoms; chronic obstructive and pulmonary diseases; airborne respiratory infections; cardiovascular mortality and morbidity; lung cancer; odor and sensory irritation in eyes and airways (Sick Building Syndrome (SBS) symptoms) [12
]; for this terminology, see below.
The term SBS has been used to define buildings in which an excessive prevalence of occupants (>20%) report one or more symptoms that may be associated with the IAQ and climate at work [13
]. However, the SBS terminology, apart from being semantically misleading, today is considered obsolete [9
], simply because no single pollution load is causative of all SBS symptoms; rather, focus is on the individual specific symptomatology and the identification of potential risk factors for specific symptoms or signs [9
]. For instance, Brightman et al. (2008) concluded that “these findings (questionnaires in buildings at large; added by authors) imply that it is counterproductive to dichotomize buildings into healthy vs. unhealthy; instead the prevalence of health problems related to buildings span a continuum” [14
]. Furthermore, the neuropsychological symptoms (e.g., headache, fatigue) “may in fact stem, at least partially, from a different origin” than exposure (added by the authors) [18
]. Thus, specific symptoms or exacerbation thereof may be associated with one or more risk factors and possibly in a concerted and amplifying manner.
Health effects potentially related to exposure to indoor air pollutants in office environments include acute and semi-acute effects and longer-term based effects. The former can be divided into immediate perceived IAQ that is related to odor perception (olfactorius nerve) and semi-acute effects that are characterized by some latency, like sensory irritation in eyes and airways (trigeminus nerve), and symptoms related to the central nervous system (e.g., headache and fatigue) [15
Many epidemiological studies have addressed IAQ and associated exposure related symptoms in office workers [6
]. For instance, one recent study showed that eye symptoms were associated with proximity to outdoor pollution like traffic, portable humidifiers, and crowded spaces [23
], for further discussion, see [17
]. Other risk factors include visual display unit work and technical causes such as inadequate ventilation [24
], low humidity [25
], or high temperature, especially regarding eye symptoms [17
]. Further, mold in moisture-damaged buildings is another exposure risk that may deteriorate the IAQ and impact susceptible people, e.g., with asthma symptoms [26
The office type also plays a role in the prevalence of symptom reporting and sickness absence [3
]; generally, the more crowded the more dissatisfaction and increase of adverse health effects [28
]. It should be noted, however, that factors like noise, distance from window, and privacy also may influence the overall perception of IAQ and the prevalence of symptoms.
Indoor symptoms have also been related to psychosocial environments and mental stress at work [2
]. For instance, an association between overall comfort, indoor symptoms, high efforts and low rewards, the mood scale, and self-estimated productivity has been observed in a large survey in modern EU office buildings [6
]. Consequently, there is an interest in exploring potential synergies between psychosocial stress and indoor air on health and comfort of office workers [20
]. It is essential to acknowledge how odor annoyance—e.g., caused by degraded building materials [35
] or generated from moisture-damage (MVOCs)—may influence general comfort; psychic reactions with nonspecific symptoms are plausible, but they would not induce direct physiological reactions like sensory irritation in eyes and upper airways [27
]. Typical symptoms after exposure to unpleasant odors are fatigue, impaired power of concentration, headache, nausea, and insomnia, including possible mood disorders [27
]. Furthermore, susceptible people—i.e., with high distress (low affectivity) or being diagnosed with asthma or multiple diagnoses of asthma/allergy—may react more intensely than people with low distress or without asthma [37
Studies in office buildings have focused primarily on acute health symptoms: unspecific symptoms of irritation of eyes, nose and mucous membranes, fatigue, and headache experienced by office worker. Longer-term effects due to continuous or repeated exposure to indoor air pollutants may be associated with aggravation of asthma exacerbation and allergic responses, oxidative stress and inflammation, chronic obstructive and pulmonary disease, lung cancer, and cardiovascular diseases. These effects are generally not evaluated in office workers due to the complexity and required resources for clinical testing, which seem unrealistic in view of occupants’ mobility and the inhomogeneity of exposures [7
Several experimental studies have demonstrated deteriorated workers’ performance caused by poor IAQ—e.g., text processing [5
]—but, also by general conditions of the office—e.g., lighting and noise [39
]. A complete understanding of the cause(s)–effect relationships and type of loss of work performance is complex. Chemical pollutants and bioeffluents, rather than carbon dioxide itself, have been suggested to cause mental distraction and stress by perceived poor IAQ [40
], but other mechanisms are also in play [40
]. For instance, Maula et al. demonstrated a weak loss in cue-utilization, but not for other performance tests by low ventilation as a metric for bioeffluents in a typical office environment [42
]. The overall concern about work performance is not only related to absenteeism and associated diseases due to the work environment (IAQ), but it may result from less comfortable working conditions, e.g. inadequate IAQ [5
] and low relative humidity [17
There is an increasing demand for (occupational health) services to assess work related risks and monitor the health status of office workers. A multidisciplinary team of experts in occupational medicine, IAQ, building physics, and toxicology, is recommended for the assessment and management of IAQ problems. A questionnaire survey is recommended as a first step, while expensive physical, chemical, and microbiological measurements should only be carried out in case of an anticipated action or strong suspicion to specific agents causing the problem or if it is required to ensure that air quality parameters are within regulatory standards/guidelines.
Guidance about the role of the occupational health service in the assessment and management of IAQ problems has been provided and includes collaboration in risk assessment, use of a questionnaire survey for comfort and health evaluation of the workers, health surveillance when already performed for other risks or in case of specific clinical examinations and health promotion.
Further, synergies with other risk factors—e.g., psychosocial stress—may potentially also be important and need to be evaluated, too.