No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
A Study of Human Reactions to Office Machines in a Climatic Chamber
... In several studies it is presumed that the aldehydes and acids are formed partly by O3 oxidation of C-C double bonds in organic molecules as, for example, unsaturated fatty acids. This is in agreement with laboratory studies of VOC emission from building materials and office equipment in the presence of O3 (Reiss et al., 1995a; Weschler et al., 1992a; Wolkoff et al., 1992). The exposure of the emission from carpets with O3 showed not only a marked decrease of styrene and 4-phenyl- cyclohexene (both common latex VOCs), but also an enhancement of the aldehyde and VOC emissions (Weschler et al., 1992a). ...
... In a simulated office environment climate study, including photocopying and laser printing, formaldehyde concentrations were significantly increased; this may be explained by the reaction of emitted O3 with unsaturated VOCs, e.g. styrene from decomposition of the toner powder binder (Wolkoff et al., 1992; cf. Leovic et al., 1996). ...
... Their main source of removal is reaction with water vapor. The half-life of 0, indoors has been estimated to be about 5-10 min in studies of a residence or office, and a climate chamber, respectively (Mueller et al., 1973; Wolkoff et al., 1992 ). O3 is more stable in dry cold environments (Boeniger, 1995), while high humidity or temperature increases its decay and reaction rates. ...
Abstract Concentrations of volatile organic compounds (VOCs) measured indoors may exceed their odor thresholds, but are usually far below TLV estimates. Even applying additivity to eye and airway irritation effects, it is difficult to rationalize increased sick building syndrome (SBS) symptoms by exposure to generally chemically inert VOCs in the indoor environment.
Several studies suggest that chemical reactions in indoor air are linked with SBS symptoms and the examination of these reactions may be necessary in order to understand the role of VOCs as causative agents of SBS symptoms.
The usual evaluation of odor annoyance of VOCs based on odor thresholds should be modified, taking into account the large variation of individual human odor thresholds for single substances, and specific additivity phenomena even at subthreshold levels of VOCs.
The conclusion of this review is that chemical reactions between oxidizable VOCs and oxidants, such as ozone and possibly nitrogen oxides, can form irritants which may be responsible for the reported symptoms. Compounds adsorbed to particles may also contribute to SBS symptoms. The individual effects of indoor pollutants may act in concert with temperature and relative humidity. New analytical methods are required to measure the oxidative and reactive species or specific markers thereof in indoor air.
... In recent years, exposure to toner dust and volatile organic compounds (VOC) emitted into the air of office rooms during operation and maintenance of laser printers or photocopiers has been discussed as a possible cause of health complaints, not only those affecting the respiratory tract, but also the immunological and nervous systems (Ewers and Nowak 2006;Gminski and Mersch-Sundermann 2006;Wolkoff et al. 1992). ...
... However, the results of studies on the biological effects caused by exposure to toners outlined in these reviews are contradictory. Whereas the in vivo studies dealing with direct exposure to toner dusts led to the assumption that neither acute nor chronic oral, dermal, or inhalation toxicity can be expected even at high concentrations (Lin and Mermelstein 1994), human biomonitoring studies provided convincing indications for irritative and genotoxic effects related to exposure to the emissions from laser printers and photocopiers (Gadhia et al. 2005;Goud et al. 2001Goud et al. , 2004Wolkoff et al. 1992). ...
... While numerous studies dealing with the direct toxicity and inhalation toxicity of toner dust are available (Gminski et al. 2011;Lin and Mermelstein 1994;Nakadate et al. 2006), investigations evaluating the effects of exposure to emissions from office machines are scarce. The first report on human health effects due to printer emissions was published in 1992 (Wolkoff et al. 1992). In this study, 30 human subjects were exposed to increased levels of ozone, formaldehyde, TVOC, and particulate matter in a chamber experiment with operating office equipment. ...
Various publications indicate that the operation of laser printers and photocopiers may be associated with health effects due to the release of gaseous components and fine and ultrafine particles (UFP). However, only sparse studies are available that evaluate the possible exposure of office workers to printer emissions under real conditions. Therefore, the aim of our study was to assess the exposure of office workers to particulate matter released from laser printers and photocopiers.
Concentrations of fine particles and UFP were measured before, during, and after the operation of laser printing devices in 63 office rooms throughout Germany. Additionally, the particles were characterized by electron microscopy and energy-dispersive X-ray spectroscopy.
A significant increase of fine particles and UFP was identified in ambient workplace air during and after the printing processes. Particle fractions between 0.23 and 20 μm emitted by the office machines significantly affect particle mass concentrations while printing 500 pages, i.e., during the printing process, PM(0.23-20), PM(2.5), and PM(10) concentrations increased in 43 out of the evaluated 62 office rooms investigated. Additionally, a significant increase was observed in submicrometer particles, with median particle number concentrations of 6,503 particles/cm(3) before and 18,060 particles/cm(3) during the printing process.
Our data indicate that laser printers and photocopiers could be a relevant source of fine particles and particularly UFP in office rooms.
... [For comparison see references 13 and 76.] Objective eye measures have also been used in controlled human exposure studies in climate chambers. For example, exposure to a simulated office environment was found to be associated with epithelial damage of the conjunctiva and reports of eye irritation (135). With a similar approach, but with building materials as sources of VOC, an association was found between reduced tear film quality (pooled break-up time, foam formation, and thickness of lipid layer) and an increase in reported eye irritation (136). ...
... [For comparison see reference 62.] It is interesting to note a weak association between an increased concentration of polymorphonuclear neutrophils in the eye and VDU work (76), including an association with enhanced epithelial damage of the conjunctiva (135). Traffic pollution, partly reflected as particle settlement on surfaces, has also been associated with eye irritation (58,76). ...
... The increase in complaints among VDU workers could, among other things, be explained in terms of an increase in osmolarity as a result of dehydration caused by enhanced water evaporation. A higher osmolarity of the tear film results in epithelial damage of the conjunctiva (1), as also observed for women in a simulated office environment study (135). ...
The study reviews eye irritation using a multidisciplinary approach. Potential risk factors and objective gender differences are identified, and possible hypotheses for eye irritation caused by indoor air pollution are discussed. Eye irritation depends somewhat on destabilization of the outer-eye tear film. An integrated physiological risk model with blink frequency, destabilization, and break-up of the eye tear film as inseparable phenomena may explain eye irritation among office workers in terms of occupational, climate, and eye-related physiological risk factors. Certain volatile organic compounds that are both chemically reactive and airway irritants may cause eye irritation. If airborne particles alone should destabilize the tear film and cause eye irritation, their content of surface-active compounds must be high. Personal factors (eg, use of contact lenses, eye make-up, and certain medication) may also affect destabilization of the tear film and possibly result in more eye symptoms.
... Hinsichtlich der gesundheitlichen Bedeutung von Expositionen gegenüber den für Laserdrucker spezifischen Emissionen wurden zuerst von Hetes et al. (1995) für die amerikanische Umweltbehörde (US-EPA) kontrollierte Expositionsstudien von Wolkoff et al. (1992) herangezogen, bei denen freiwilli-ge Probanden, die in einer Expositionskammer gegenüber Emissionen aus Laserdruckern exponiert waren, mit Kopfschmerzen und Reizungen der Schleimhäute sowie Trockenheit der Augen, Nase und des Rachens reagierten. Gesundheitliche Beschwerden im Zusammenhang mit der Nutzung von Laserdruckern und Kopieren wurden später auch im arbeitsmedizinischen Bereich geäußert und untersucht. ...
... Analysen zur Veränderung der Innenraumluftqualität (Stäube, VOC, Ozon, Formaldehyd) beim Betrieb von Druckern und Kopieren in Realräumen. (Wolkoff et al. 1992), in der irritative Effekte infolge laserdrucker-bzw. kopierer-assoziierter Innenraumluftbelastungen beschrieben wurden. ...
Since some years exposure to toner particles and volatile compounds that are emitted into indoor air during laserprinter and photocopier operation or maintainance is discussed as responsible for health complaints, especially regarding effects on the respiratory tract and the immunological and nervous system. Chamber investigations and indoor air measurements which determined emissions of laser printers and photocopiers have shown that fine particles of toners and papers and ultrafine particles, gases such as ozone and various volatile organic compounds (VOC) are released into indoor air. Therefore, an exposure to widely undefined complex mixtures consisting of particles and chemical compounds can be assumed while operating office machines. In the present review studies published in the international literature and illuminating the significance of health effects caused by both direct exposure to toner particles and exposure to emissions of laser printers and photocopiers are summarized and evaluated. For that, data of exposure values (chamber and indoor measurements), in vitro studies using bacteria and cell models, in vivo studies with animals, human exposure studies, investigations dealing with human effect markers (biomonitoring), epidemiological and occupational studies were critically analysed. Additionally, emission rates and exposures to chemical compounds or classes released during operation of office machines were related to biological threshold values. The results of the studies on biological effects included in this review are contradictory. Whereas in vivo studies dealing with direct exposure to toner dusts led to suppose that whether acute nor chronic, oral, dermal and inhalative toxicity can be expected even in high concentrations, human biomonitoring studies provided convincing indications for irritative and genotoxic effects related to the exposure to emissions of laser printers and photocopiers. Although numerous studies are available dealing with the direct toxicity and inhalation toxicity of toner dust investigations evaluating the significance of exposure to emissions of office machines during operation are scarce. So far there are only slight indications for health effects, but due to that lack of data many questions regarding an association between emissions of office machines and health complaints or damage to health can not be answered yet from the scientific point of view. Since laser printers and photocopiers are increasingly used not only in offices but also in private homes additional in vitro and in vivo studies, controlled human ex-posure studies using reliable biological markers and epidemiological surveys are indispensable for human risk assessment.
... Use of beauty care products and perfumes by the occupants of the house might have led to the increase of VOC concentration. Previous studies have also suggested that the use of these products gradually increases the VOC concentration in a poorly ventilated room (Wolkoff et al. 1992;Wolkoff 1995). ...
Real-time particulate matters (PM1, PM2.5, PM4, PM7, PM10, and TSP) with AEROCET 531S (USA), gaseous pollutants (NO2 and TVOC) with Aeroquel 500 gas sampler (NZ) were measured from the indoor air of houses at four residential locations in Dhaka, Bangladesh. PM10 samples were collected on quartz filters with a dual channel dust sampler (IPM-FDS 2510, India) for selected trace metal determination from five houses of Dhaka. Respiratory function of the occupants was assessed by using a peak expiratory flow meter (Rossmax PF 120). Mean PM1, PM2.5, and PM10 concentrations were 46.1 ± 13.4, 76.0 ± 16.2, and 203.9 ± 44.8 μg m⁻³, respectively. Higher enrichment factors of Pb, Zn, and Ni were found for traffic, industrial, and constructional activities. The correlation between indoor and outdoor PM2.5 (R² = 0.42) and ratios (I/O < 1) suggesting indoor air was effected by outdoor air. The concentration of NO2 (0.076 ± 0.007 ppm) and TVOC (90.0 ± 46.0 ppm) was found above than other studies. The average total hazard ratio (THR) in Dhaka was 9.06 and has the highest exposure to air pollutants (PM2.5, PM10, NO2) in Khilkhet (THR 10.1) residents. A negative association between ultra-fine particles (PM1) and peak flow rate measurements of the residents living in these houses indicates that inhalations of ultra-fine particles has great influence on the reduced lung efficiency.
... In this process, pollutants like O 3 , hydrocarbons, volatile organic compounds and dust are released causing indoor air quality problems (Lee et al. 2006). Among these gases, ozone is highly toxic gas and it is one of the most serious health risks which results in health issues such as headache, dryness in eyes, mucous irritation and tight and dry facial skin (Wolkoff et al. 1992). ...
“Knowledge is power” and distribution of knowledge is fueled by printing and photocopying industry. Even as printing and photocopying industry have revolutionized the availability of documents and perceptible image quickly at extremely inexpensive and affordable cost, the boon of its revolution has turned into a bane by irresponsible, uncontrolled and extensive use, causing irreversible degradation to not only ecosystem by continuous release of ozone and other volatile organic compounds (VOCs) but also the health of workers occupationally exposed to it. Indoor ozone level due to emission from different photocopying equipment’s increases drastically and the condition of other air quality parameters are not different. This situation is particularly sedate in extremely sensitive educational and research industry where sharing of knowledge is extremely important to meet the demands. This work is an attempt to catalogue all the environmental as well as health impacts of printing or photocopying. It has been observed that printing/photocopying operation is a significant factor contributing to indoor air quality degradation, which includes increase in concentration of ozone, VOCs, semi-volatile organic compounds (SVOCs) and heavy metals such as cadmium, selenium, arsenic, zinc, nickel, and other pollutants from photocopy machines. The outcome of this study will empower the manufactures with information regarding ozone and other significant emission, so that their impact can be reduced.
... meat cooking), exacerbating its risk level indoors on top of its common emissions from other indoor sources like furniture and building materials [5,6]. The ozonolysis of volatile organic compounds (VOCs) was also found to be a source of HCHO as a result of laser-printing [7,8]. ...
Catalytic oxidation at ambient temperature has drawn wide attention as a new promising method of air cleaning, converting hazardous materials into non-hazardous ones. However, limited information is available regarding catalytic filter performance/characteristics under real operating conditions, especially on service efficiency and byproducts. Also, no practical scale-up method/evidence for filter performance evaluation is currently available to scale-up laboratory results to real application conditions. These limitations and knowledge gaps prevent building owners/designers from adopting this new promising technique in their commercial/industrial applications. The present study conducted experiments from small-scale to full-scale chamber tests which challenged a developed catalytic filter under realistic conditions. Formaldehyde was selected for approach demonstration due to its indoor ubiquitousness and criticality for human health even at low-levels. Results showed that the competition level for reaction sites in filter media had a crucial role in the performance for formaldehyde abatement, a high initial (77%; under no competing pollutants) to a typical stable level(23-32%), depending on the coexistence of other pollutants and moisture in the air, that the employment of this type of filter might generate byproducts (opposite to previous literature reports), and that small-scale column tests represented a good indication for large-scale filter performance as a practical screening method.
... Pioneering studies in this area concerning chemical compounds emitted from office machines were carried out in the 1990s of the 20th century (Wolkoff 1990;Wolkoff et al. 1992Wolkoff et al. , 1993Leovic et al. 1996;Brown 1999). Office devices can release VOCs partly generated by toners and inks that are subject to heating during the printing process, as well as particles of paper. ...
Office devices can release volatile organic compounds (VOCs) partly generated by toners and inks, as well as particles of paper. The aim of the presented study is to identify indoor emissions of volatile halogenated organic compounds into the office workspace environment. Mixtures of organic pollutants emitted by seven office devices, i.e. printers and copiers, were analyzed by taking samples in laboratory conditions during the operation of these appliances. Tests of volatile organic compound emissions from selected office devices were conducted in a simulated environment (test chamber). Samples of VOCs were collected using three-layered thermal desorption tubes. Separation and identification of organic pollutant emissions were made using thermal desorption combined with gas chromatography coupled to mass spectrometry. Test chamber studies indicated that operation of the office printer and copier would contribute to the significant concentration level of VOCs in typical office indoor air. Among the determined volatile halogenated compounds, only chlorinated organic compounds were identified, inter alia: trichloroethylene - carcinogenic - and tetrachloroethylene - possibly carcinogenic to human. The results show that daily exposure of an office worker to chemical factors released by the tested printing and copying units can be variable in terms of concentrations of VOCs. The highest emissions in the test chamber during printing were measured for ethylbenzene up to 41.3 mu g m(-3), xylenes up to 40.5 mu g m(-3) and in case of halogenated compounds the highest concentration for chlorobenzene was 6.48 mu g m(-3). The study included the comparison of chamber concentrations and unit-specific emission rates of selected VOCs and the identified halogenated compounds. The highest amount of total VOCs was emitted while copying with device D and was rated above 1235 mu g m(-3) and 8400 mu g unit(-1) h(-1) on average.
... However, exposure-effect relationships have to be established first. One approach is human ex- posure studies with building materials Wolkoff et al., 1991) and office equipment ( Wolkoff et al., 1992). Alternatively, bioassays for esti- mation of irritation of the upper airways in humans may be used (Nielsen and Alarie, 1992;Tepper and Costa, 1992;Tucker, 1993). ...
Abstract The impact on air quality of the emission of pollutants from freshly conditioned sealant and waterborne paint, and a new carpet was investigated by means of a closed emission system and a high loading factor, i.e. “maximized” test conditions. VOCs were measured. Speciated TVOC values obtained by summation of single VOCs and TVOC (cyclohexane equivalents) values determined by IR spectroscopy were of the same order of magnitude for the carpet and for the sealant. Biological evaluation of the effects of the VOCs was undertaken from the concentrations and the odour and irritation thresholds of each substance. The overall agreements and the mutual supplementation of the results from the TVOC and biological evaluations were apparent, suggesting that both approaches should be part of the evaluation of emissions from building materials. Also the mouse bioassay (ASTM, 1984) was used for evaluation of the irritants emitted. Chemical emission testing and the use of established lists of irritation thresholds appear to be more cost-effective, due to the low sensitivity of the bioassay. This approach was demonstrated with 2-butanone oxime (emitted from the sealant). The same type of approach may be used in relation to odour and hazard identification. However, human and animal tests are necessary in cases where biological data are lacking or where the chemical emission is unknown.
... In another study, eye irritation among workers in joinery shops and repair of cement kiln, respectively, turned out to be significant, and this could partly be associated with terpene/ozone reactions, although ozone was not measured (Eriksson et al., 1997; Sanderson et al., 1999). Eye symptoms were also found to be significant in a human exposure study carried out in a simulated office environment, in which subjects were engaged in typical office work including photocopying and laser printing (Wolkoff et al., 1992). In this study, a significant formaldehyde production was observed that might be related to reactions between ozone and toner powder VOCs (e.g., styrene) and human exhalation of isoprene (Fenske and Paulson, 1999). ...
It is generally believed that indoor air pollution, one way or another may cause indoor air complaints. However, any association between volatile organic compounds (VOCs) concentrations and increase of indoor climate complaints, like the sick-building syndrome symptoms, is not straightforward. The reported symptom rates of, in particular, eye and upper airway irritation cannot generally be explained by our present knowledge of common chemically non-reactive VOCs measured indoors. Recently, experimental evidence has shown those chemical reactions between ozone (either with or without nitrogen dioxide) and unsaturated organic compounds (e.g. from citrus and pine oils) produce strong eye and airway irritating species. These have not yet been well characterised by conventional sampling and analytical techniques. The chemical reactions can occur indoors, and there is indirect evidence that they are associated with eye and airway irritation. However, many other volatile and non-volatile organic compounds have not generally been measured which could equally well have potent biological effects and cause an increase of complaint rates, and posses a health/comfort risk. As a consequence, it is recommended to use a broader analytical window of organic compounds than the classic VOC window as defined by the World Health Organisation. It may include hitherto not yet sampled or identified intermediary species (e.g., radicals, hydroperoxides and ionic compounds like detergents) as well as species deposited onto particles. Additionally, sampling strategies including emission testing of building products should carefully be linked to the measurement of organic compounds that are expected, based on the best available toxicological knowledge, to have biological effects at indoor concentrations.
... The consequence of the extensive use of modern ofÿce equipment is that ooce workers are exposed to an ooce climate giving rise to health eeects such as headache; mucous irritation and dryness in the eyes, nose and throat; and dry and tight facial skin. Researchers, including Wolkoo et al.345, reported that the operation of ooce equipment not only contribute to increase indoor air pollutant concentrations , but also, in some cases, has been associated with health complaints from exposed workers. The increased levels of ozone, volatile organic compounds (VOCs) and formaldehyde in a chamber evaluation of operating ooce equipment were observed in many researches. ...
Indoor air pollution in working places is widely recognized as one of the most serious potential environment risks to human health (WHO, Indoor air quality research: Report on a WHO meeting Stockholm 1984, Euro-reports & Studies 103, WHO, Copenhagen, Denmark 1986, p. 1–64). A stainless steel flow-through environmental chamber was used to characterize the emissions rate of pollutants from office equipment. Different types of office equipment (including fax machines, laser printers, ink-jet printers, scanners, and photocopying machines) were investigated. The concentration of volatile organic compounds (VOCs), total VOC (TVOC), ozone, respirable particles (PM10) and temperature were measured. Characterization the species of VOCs was carried out by gas chromatography—mass selective detector (GC-MSD). The highest emission rates of VOCs compounds were toluene, ethylbenzene, m,p-xylene, and styrene. Results showed that emissions of ozone and VOC from laser printers were significantly higher than that from ink-jet printers. The emission rates of TVOC varied from copy(ink-jet printer) to copy(laser-jet).
... Various types of printers are widely used in offices and homes around the world and have become standard indoor electronic equipment. They not only bring convenience to humans, but also have been suspected as a potential source of indoor air pollutants (Wolkoff et al., 1992;Wolkoff, 1999). Some case reports and a few studies have suggested that some common office environment exposures, such as exposure to carbonless copy (CCP) (Morgan and Camp, 1986;Shehade et al., 1987;LaMarte et al., 1988;Skov et al., 1989;Kanerva et al., 1993;Jaakkola and Jaakkola, 1999) and fumes from photocopies and printers (FPP) affect health adversely (Skov et al., 1989;Jaakkola and Jaakkola, 1999;Yassi and Warrington, 1988;Fisk et al., 2004;Stenerg et al., 1993). ...
The release of ultrafine particles from office equipment is currently receiving great concerns due to its potential threat to human health when inhaled. Printer toner is one of the largest consumables in daily office work, and the particles released from printers and photocopiers may pose damage to respiratory system. In this study, we found the particles can be released into the surrounding environment during the printing process and the concentrations of PM(2.5) and PM(10) particles increased obviously. To evaluate the time-course pulmonary responses caused by toner particles, the toner suspension was instilled into the lungs of the male mice through intratracheally instillation every other day for four times and the pulmonary responses of the lung were monitored at days 9, 28, 56 and 84. Indeed, mice treated with toner particles displayed a slower body weight growth rate during the recovery phase. The total cell number in bronchoalveolar lavage fluids (BALF) of toner-exposed groups was much higher than the saline-treated groups. The total protein, lactate dehydrogenase and acid phosphatase in BALF exhibited significant changes (p<0.05 or p<0.01) at different time points. The nitric oxide synthase, interleukin 1-beta, and interleukin 6 in the lung tissue of the toner-exposed groups also exhibited significant changes (p<0.05 or p<0.01). The pathological examination showed that toner particles can adhere to the alveolar septal walls, then enter into the alveoli and cause pulmonary lesion. During the experimental period, particles phagocytosed by alveolar macrophages (AMs) led to an increase of both AMs number and apoptosis. The pulmonary stress still remained over time even with a clearance period for 12 weeks. These results indicate that exposure to toner particles can inhibit the normal growth of the mice and induce significant inflammatory responses and lesion in the lung tissues. The health and safety effects from working indoors in offices with fumes and particles released from photocopiers and printers need to be paid more attention.
... Some chambers are constructed for studies of the effect on the respiratory system of air, humidity, temperature and irritants. Some are used in research concerning office machines and the sick building syndrome (SBS) (Wolkoff e/ ai, 1992; Horak el ai, 1994). Smaller exposure chamber systems for animals are more frequently described (Phalen, 1984; Karg el ai, 1992). ...
A new whole-body exposure chamber for human skin and lung challenge offers possibilities for experimental exposure challenges carried out in clinical practice, for exposure of patients, in research and for investigations of the effects of exposure on the skin and in the respiratory tract. The chamber system can be used for both aerosols and gases. Dynamically controlled, the chamber is relatively easy to operate and to clean. Air exchange rates can be varied between 6-12/h. Initial studies with wheat flour have been carried out. The homogeneity and stability of the wheat flour aerosol concentration (the spatial and the temporal variation) inside the chamber can be kept at acceptable levels.
... Some examples of secondary VOC emissions from building products and equipment a Building product Secondary VOCs Condition Literature Carpet Aldehydes, formaldehyde, Knudsen et al., 1999; Wolkoff, 1998; Brzezinski et al., 1996 wool based aldehydes, acids, Ozone Weschler et al., 1992 benzothiazol Heat Sollinger et al., 1993 Carpet cushion Acetic acid Waterrnitrogen Schaeffer et al., 1996 Cork Acetic acid, furfural Heat Horn et al., 1998 Duct lines C aldehydes, fatty acids, Ozone Morrison et al., 1998 6,8 ᎐ 10 Furniture coating Aldehydes, acrylates, Salthammer et al., 1999 isocyanates, styrene, terpenes Linoleum Aldehydes Jensen et al., 1996 unsaturated aldehydes Water Wolkoff et al., 1995 Alkyd paint C and C aldehydes, fatty Rothweiler et al., 1993; Ullrich et al., 1992 3 5 ᎐ 6 'natural' paint acids, terpenes Volland and Zolter, 1996; Zellweger et al., 1997¨Ž . Office equipmentr Formaldehyde, aldehydes Ozone Leovic et al., 1996; Wolkoff et al., 1992 humans Ž . Paint acrylic, latex Aldehydes, formaldehyde, Chang and Guo, 1998; Knudsen et al., 1999; Young, 1992; acetaldehyde, formic acid Ozone Reiss et al., 1995 Ž . ...
The primary emissions of VOCs (e.g. solvents) from building products influence the perceived indoor air quality during the initial decay period. However, secondary emissions will continue thereafter (chemical or physical degradation, e.g. oxidation, hydrolysis, mechanical wear, maintenance), in addition to sorption processes. Emission testing for primary VOC emissions is necessary, but insufficient to characterise the impact of building products in their entire life span on the perceived air quality. Methods to distinguish between the two types of emissions are required. Also, the influence of climate parameters on the emission rates is necessary to know for proper testing. Future product development and selection strategies of new building products should consider the secondary emissions, in addition to the contribution from the use of auxiliary agents for cleaning, maintenance, and other potential impacts either physical or chemical in nature. Some of the requirements for emission testing are discussed in terms of secondary vs. primary emissions in order to develop 'healthier/better' building products for the indoor environment. In addition, some of the assumptions about the possible impact of VOCs on health and comfort in the indoor environment are presented. Odour thresholds for VOCs are one or more orders of magnitude lower than the corresponding airway irritation estimates, and it also appears that chemically non-reactive VOCs are not sufficiently strong irritants to cause airway irritation at concentrations normally encountered indoors. Finally, future requirements for analytical laboratory performances is proposed to accommodate the increasing need to establish which VOCs may be responsible for the perception of odour intensity from building products.
... The former have been used 20 extensively for studying the effects of allergens (2,3,4,5) . They have also been used in studies 21 involving high aerosol concentrations in the work place (6) ; the effects of office machines and 22 buildings on workers (7) , and air pollution (8) . Chambers for whole-body vapor exposure have not 23 been discussed as extensively in the literature . ...
A chemical vapor exposure chamber was designed to permit the study of whole-body vapor exposure of individuals wearing full protective clothing and equipment systems. A methodology also was developed to quantify the vapor protection performance of chemical protective ensembles (CPE) under safe and validated laboratory procedures. The principal research objectives were to (1) provide a methodology to accurately assess the performance of CPE and equipment under different environmental and chemical vapor challenge conditions; (2) quantify the vapor protection on a per body region basis; (3) have a systems level tool to aid in the research and development of more effective CPE for use in chemical biological environments; and (4) have a safe and reliable means of qualifying new CPE on the basis of vapor protection. Although designed for the evaluation of military-style protective equipment, the procedures apply equally to other styles of CPE used by civilian agencies such as firefighters, police, and hazmat units. The chamber and methodology were specifically designed to examine the vapor protection performance of clothing ensembles, including the details of protection variation over the body. A variety of exposure conditions appropriate to indoor and outdoor scenarios are possible, including the effects of wind, temperature, and relative humidity. Protection performance results from a number of individuals wearing typical military-style CPE are presented. These results demonstrate that there is no such thing as a unique protection performance level obtained for a given CPE. Rather, the individual and the ensemble interact differently in each situation, resulting in a protection performance distribution for individuals, and for groups of wearers, even under a standardized set of exposure conditions.
... For example, a thinner lipid layer of the PTF during the working day, an APTF measured as lower BUT, and more dry spots formation were found among office workers with a higher prevalence of eye and airway irritation symptoms (sick building syndrome) than in the general population (Brasche et al., 2001;Franck, 1986;Franck et al., 1993). Some of these objective alterations have also been observed in human exposure studies in climate chambers with office equipment and certain building materials (Wolkoff et al., 1991(Wolkoff et al., , 1992. ...
Eye irritation is a common complaint in the office environment. The purpose of this overview is to merge knowledge within indoor air science, ophthalmology, and occupational health to promote understanding eye irritation symptomatology, the cause of which is still partly unknown. High periocular relative humidity appears to protect the pre-corneal tear film against desiccation and sensory irritating pollutants and reduces the development of eye irritation symptoms. This is particularly relevant for intensive computer work, where the pre-corneal tear film is altered resulting in dry spot formation and eye dryness, in addition to enhanced susceptibility towards sensory irritating pollutants. The workplace, thermal conditions, and work schedule (including breaks) should be planned in such a way to help maintain a normal eye blink frequency to minimize alterations of the pre-corneal tear film. The role of relative humidity on eye irritation symptoms should not be underestimated. Multiple short breaks are justified by the beneficial effect on the pre-corneal tear film. In addition, longer breaks in tasks, which require demanding visual work, should be considered. In addition, air temperature as well as certain alkene oxidation products by ozone may worsen eye irritation symptoms, but the latter factor may be smaller at higher relative humidity.
The indoor environment is characterized by a dynamic nature in particular from various emission sources contributing with volatile organic compounds. An under-standing and consideration of all potential indoor pollution sources, their emission characteristics, and the interrelationship of various indoor air quality parameters are prerequisite for the design and development of a sampling strategy. This includes parameters like the time of sampling, sampling duration and frequency, and selection of the sampling location. The field measurements of various studies show the importance of considering time as well as on a long-term as on a short-term basis.
The quality of indoor air is influenced by chemical contamination from several sources. The main sources of indoor air pollution are infiltration of the outdoor air, volatile compounds from contaminated ground, and emissions from building materials. Naturally, the indoor use and generation of chemicals are relevant sources too. The research activities of the Institute for Ecological Chemistry have been focused on the behavior of semivolatile organic compounds (SVOCs) coming from wood preservation paints used indoors, case studies following problems dealing with indoor air quality, and the occurrence of indoor volatile organic compounds (VOCs) in the Bavarian region.
Both building materials and office machines emit volatile organic compounds thus demanding for methods to evaluate the health aspects of their emission. Chamber studies with subjects differ from field studies in that measurements and reporting of symptoms can be carried out simultaneously. The exposure of voluntary subjects to selected building materials, and to a simulated office environment with selected office machines have been studied, respectively. A multidisciplinary approach has been used by combining air quality measurements with clinical investigations, the irritating potency of a mouse bioassay, and air quality evaluations on the decipol scale. This has given important information about the pollutants emitted, their relation to objective air quality measurements, and the tear film quality of the eye.
No model is well established for indoor air induced eye irritation — a consequence of the lack of good models for the common chemical sense in general and even more a consequence of the extreme lack of data. We have to use the understanding from models established in other situations or related to other organs. Existing models suggest that indoor air pollutants may decrease the stability of the tear film either by changing the surface lipid layer or by decreasing the amount of mucus in the water-phase of the film. This may then lead to increased dryness and subsequently damage the corneal and conjunctival epithelium. This may by itself or by increasing sensitivity of the nociceptors in the epithelium lead to increased sensory irritation. Furthermore, inflammatory responses may follow due to release of eg. neuropeptides from the nociceptors. Another mechanism suggested is that inflammatory responses leads to release of mediators triggering nociceptors (histamine release is an example). Reports (epidemiological and and experimental) support that dust and volatile organic substances (VOCs) may induce decreased tear film stability, increased epithelial damage, increased inflammatory responses as well as sensory irritation. Furthermore, there seem to be some association between objective parameters and subjective irritation for Polymorphonuclear neutrophils and tear film stability. This is remarkable results, achieved within the past 5 years. However, data is not sufficient to decide about the reliability of pathophysiological relations suggested in the models. The main future need is to gather more data on these methods and further development and refinement of measurement techniques.
By means of electrical discharge between two electrodes a special type of air cleaning devices generates a non-thermal plasma (NTP) consisting of particles of high energy, which are supposed to react with air pollutants to form toxicologically harmless products. Theoretical considerations and literature data justify doubts about attainable complete oxidation of organic indoor air pollutants by this technology. The generation of ozone caused in this process is inevitable and its release probable. According to the information available a sound hazard assessment acccording to the German Act on Occupational Health and Safety (Arbeitsschutzgesetz) and the new Ordinance on hazardous substances of 2004 is not possible. Therefore, the operation of such devices in direct proximity of persons cannot be recommended.
Use of laser based printing systems is commonplace worldwide, both in the workplace and at home. However these devices can be significant sources of volatile organic compounds (VOCs) and ultrafine fine particles emitted into indoor air. The aim of this study was to investigate the cytotoxic and genotoxic effects of laser printer emissions to A549 human lung cells using second-hand laser printers with low to mediumthroughput. Furthermore, the possible association of biological effects from release of ozone (O3), volatile organic compounds (VOCs), particulate matter (PM) and submicrometer particles (SMPs) was studied. The experiments were performed in a 1 m 3 emission chamber coupled to a Vitrocell®-cultivation and exposure system (Biological Chamber Emission System; BIKAS). BIKAS allows direct exposure of cells to clean air or to LDS emissions at the air/liquid interface. After 1 h of exposure, cytotoxicity and genotoxicity were determined by the WST-1 assay and the micronucleus test (CB MNvit), respectively. The five investigated laser printers emitted various amounts of ozone, VOCs, PM and SMPs during their printing activites. The ozone concentrations emitted were relatively low. VOC emissions included at least 13 compounds, including 2-butanone, hexanal, m,p-xylene, and o-xylene. Total VOC concentrations ranged from 95 to 280 ìg/m3. The average PM concentrations were below 2.4 μg/m3. The concentrations of SMPs during standby mode were found to be 9 to 26 particles/cm3. For three of the investigated laser printers, the SMP concentrations increased during printing activites by the factor 85- to 16,000, with one of the printers reaching more than 290,000 particles/cm3. None of the emissions from the five models showed cytotoxic effects. In contrast, for two of the printers studied, a significant increase in micronucleus induction was achieved (p <0.001, chi 2-test). Interestingly, no clear association was found between biological activities and release of ozone, VOCs, PM or SMPs Thus, the influence of emission components on biological activites must be discussed with respect to the quality of PM or SMP or with respect to possible combination effects.
A new whole-body exposure chamber for human skin and lung challenge offers possibilities for experimental exposure challenges carried out in clinical practice, for exposure of patients, in research and for investigations of the effects of exposure on the skin and in the respiratory tract. The chamber system can be used for both aerosols and gases. Dynamically controlled, the chamber is relatively easy to operate and to clean. Air exchange rates can be varied between 6-12/h. Initial studies with wheat flour have been carried out. The homogeneity and stability of the wheat flour aerosol concentration (the spatial and the temporal variation) inside the chamber can be kept at acceptable levels.
IntroductionVOC Exposures IndoorsSummary of Experimental Evidence of Health Effects of VOC ExposureConclusions
References
To guide the selection and design of air filter/cleaning devices for improving IAQ, it is important to be able to assess the performance and characteristics of filter media within a reasonable/practical testing period for the low concentrations conditions (~50 ppb) under which they are applied. The study objectives were to investigate whether filter media showing good performance at high concentrations per ASHRAE 145.1-2008 would also perform well at low concentrations typical indoors, and to explore whether and how existing
models for filtration media beds can be applied to predict and extrapolate the experimental performance results obtained under high concentrations. Six filter media having different filtration property, pellet shape and size, and target compound were selected for this investigation. Experiments were performed at both high (~1 ppm/100 ppm) and low (~50 ppb) levels of O3/NO2 concentration for all media selected. Existing models were valuated for the feasibility of data extrapolation from high to low concentration conditions. The results showed that 1) the relative performance of filter media at high concentration was qualitatively indicative of that from the low concentration results; and 2) no existing models are suitable for any media having major catalytic removal characteristics for the cases studied, and an improved mechanistic model needs to be developed.
Presently, no standard test method exists to evaluate the various emissions from office equipment (e.g., ozone, volatile organic compounds, inorganic gases, and particulates) so it is difficult to compare data from different studies.1 As a result, the authors are developing a standardized guidance document for measuring indoor air emissions from office equipment. The ultimate goal is to apply the test method to better understand emissions from office equipment and to develop lower emitting machines. This paper provides background information on indoor air emissions from office equipment with an emphasis on dry-process photocopy machines. The test method is described in detail, along with the results of a study to evaluate the test method using four dry-process photocopy machines.The results from this study indicate that the test method provides acceptable performance for characterizing emissions; that it can adequately identify differences in emissions between machines both in compounds emitted and their emission rates; and that it is capable of measuring both intra- and inter-machine variability in emissions. Challenges and complications were encountered in developing and implementing the test method. These included heat generation, which can cause large increases in chamber temperature; finite paper supplies for photocopy machines, which limit test duration; varying power requirements that may require changes in chamber electrical supply; and remote starting of the machines, which is necessary to maintain chamber integrity.Results show that dry-process photocopy machines can produce emissions of ozone and volatile organic compounds that can potentially have a significant impact on indoor air quality. For the four machines tested in this study, the compounds with the highest emission rates overall were ethylbenzene (28,000 µg/hour), m,p-xylenes (29,000 µg/hour), o-xylene (17,000 µg/hour), 2-ethyl-lhexanol (14,000 µg/hour), and styrene (12,000 fig/hour). Although many of the same compounds tended to be detected in emissions from each of the four photocopiers, the relative contribution of individual compounds varied considerably between machines, with differences greater than an order of magnitude for some compounds.
Abstract The amount of volatile organic compounds (VOCs) in indoor air, usually called TVOC (total volatile organic compounds), has been measured using different definitions and techniques which yield different results. This report recommends a definition of TVOC referring to a specified range of VOCs and it proposes a method for the measurement of this TVOC entity. Within the specified range, the measured concentrations of identified VOCs (including 64 target compounds) are summed up, concentrations of non-identified compounds in toluene equivalents are added and, together with the identified VOCs, they give the TVOC value.The report reviews the TVOC concept with respect to its usefulness for exposure assessment and control and for the prediction of health or comfort effects. Although the report concludes that at present it is not possible to use TVOC as an effect predictor, it affirms the usefulness of TVOC for characterizing indoor pollution and for improving source control as required from the points of view of health, comfort, energy efficiency and sustainability.
The presence of Volatile Organic Compounds (VOC) in indoor air has in past decades often been associated with adverse health effects such as sensory irritation, odour and the more complex set of symptoms called the Sick Building Syndrome (SBS). More recently, a possible link between the increase in the prevalence of allergies throughout the industrialized areas of the world and exposure to elevated concentrations of VOCs has been suggested. In many cases, the total VOC (TVOC) is used as a measure of the concentration of air pollution and, by extension, as a measure of the health risk in non-industrial buildings. However, the TVOC concept has been questioned for a number of reasons, including the facts that it is an ambiguous concept, that individual VOCs making up the whole can be expected to give rise to different effects in people and that researchers have been using different definitions and interpretations of TVOC. This means that simple addition of the quantities of individual VOCs may not be relevant from a health point of view.
The modification in reactivity of styrene by ozone and water was investigated on TiO2(110) as a model for heterogeneous reactions of hazardous pollutants using temperature programmed desorption. Styrene desorbs from TiO2(110) at 180, 270, and 340 K, in peaks tentatively assigned here to multilayer sublimation and desorption from Ti4+ in the first layer and defects (including step edges), respectively. Water and styrene compete for sites when these species are coadsorbed, resulting in a shift of the 270 K styrene desorption peak to 200 K. Styrene, however, is still able to bind to defects. Ozone preadsorption suppresses styrene desorption associated with defects but results in a new styrene desorption feature at 535 K. Ozone also promotes styrene oxidation to formaldehyde (325 K), benzaldehyde (380 K), and styrene epoxide (545 K). Two pathways for the reaction of ozone with styrene were identified. First, ozonolysis of the terminal CC bond of styrene occurs, yielding benzaldehyde and formaldehyde, analogous to the gas-phase reaction. Second, a surface-mediated reaction converts styrene to styrene epoxide. The saturation behavior and thermal stability of the corresponding oxidizing species suggests it is possibly the result of surface-mediated decomposition of ozone into adsorbed O adatoms. Our results suggest that the heterogeneous thermal chemistry of styrene, and possibly nonpolar organic molecules in general, is dependent on moisture and ozone levels in the air, and that volatile organic compound (VOC) concentrations can be significantly affected by anthropogenic interfaces such as titania-containing paints and coatings.
Abstract Volatile organic compounds (VOCs) have been simultaneously measured indoors and outdoors at 50 sparsely occupied telecommunications (Telco) offices, 9 variably occupied data centers and 11 densely occupied administrative (Admin) offices. Comparisons among the three building types, as well as within each of the building types, showed the influence of ventilation and sources. On average, the Telco and Admin facilities were better ventilated than the Data Centers, and the geometric mean of the I/O's for ∑VOC (sum of the concentrations of identified VOCs) at Telco (3.2) and Admin (5.3) facilities were lower than at Data Centers (8.6). Admin Offices had more and stronger sources than Telco Offices; when comparably ventilated facilities were compared, many VOCs had I/O ratios that were significantly larger at the Admin Offices. Furthermore, certain VOCs were detected in Admin but not Telco Offices. The influence of human occupancy on indoor VOCs was gauged by comparing sparsely and densely occupied buildings. Octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), n-dodecane (n-C12) through n-hexadecane (n-C16), limonene, and, to a lesser extent, tetrachloroethylene were all present in higher concentrations when there were more occupants (per unit area). Within this set of compounds, D5 was the best marker of occupant density.
The emission of volatile organic compounds (VOC) from nine toner powders and eleven types of processed paper from photocopying machines (6), laser (3) and matrix printers (21, and one carbonless copy fm has been measured. A total of 61 VOC from toner powders were identified by heating (185 °C) the powder for three minutes for thermal desorption and by gas chromatography followed by the use of low and high resolution EI and CI mass spectrometry. VOC from processed paper were analyzed by headspace sampling on Tenax TA from nylon bags. Thirty-one VOC with a wide range of volatility and persistency were identified from processed paper. The total VOC emission from the various types of paper differed substantially. Using the field and laboratory emission cell (FLEC), the calculated initial emission rate of styrene was 5 μg m−2h−1 from a freshly processed paper The VOC emission from machines and the processed paper can be reduced by proper choice of o m e equipment. However, an evaluation should consider all potential pollutants.
Abstract Adjustment of ventilation rates in buildings is widely practised, both to provide good air quality on a proactive basis and to mitigate air quality problems associated with occupant complaints. However, both cross-sectional and experimental epidemiological studies have reported mixed results and have for the most part failed to establish definitive relationships between ventilation rates and symptom prevalence or dissatisfaction with air quality. The difficulties involved in establishing such relationships may be due to a variety of confounding factors which include limitations in study design and interaction effects; difficulties in controlling ventilation rates in experimental studies; inadequate mixing of supply air in occupied spaces; high source strengths for some contaminants; dynamic interactions between sources and ventilation rates that result in increased contaminant emissions; contaminant dose-response sensory effects which are log-linear; potential contaminant generation within ventilation systems themselves; and multifactorial genesis of sick building symptoms.
There is limited evidence to suggest that ventilation rate increases up to 10 L/s person may be effective in reducing symptom prevalence and occupant dissatisfaction with air quality and that higher ventilation rates are not effective. Because of complex relationships between ventilation rates, contaminant levels, and building-related health complaints/dissatisfaction with air quality, the use of ventilation as a mitigation measure for air quality problems should be tempered with an understanding of factors which may limit its effectiveness.
Total volatile organic compounds (TVOC) are determined in intake, room-supply and room air in 86 office rooms in 29 office buildings in northern Sweden. Measurements of formaldehyde were also made in room air. Building and room characteristics were identified and symptom reports collected from 1087 office workers. Concentrations of TVOC and formaldehyde in room air were low, with mean values of 71 µg/m3 and 31 µg/m3, respectively. The TVOC concentration was generally lower in room air than in supply air or intake air. The “loss” (difference in measured values) of TVOC from supply to room air was associated with raised concentrations of formaldehyde and raised prevalences of occupant symptoms. High TVOC concentrations in room air were associated with reduced prevalences of occupant symptoms.
Analyses of indoor air samples of semivolatile organic compounds (SVOCs) from five offices in two office buildings, a school classroom, and a room in a day-care center were generally strongly influenced by artifact formation. In the laboratory, the major artifacts could be produced by sampling mixtures of O3, NO2, and limonene in air on the sorbent, Tenax TA. Several SVOCs from O3 degradation of Tenax TA were detected, but only few were identified. The NO2 degradation of Tenax TA analyzed by thermal desorption and gas chromatography (TD-GC) almost exclusively formed 2,6-diphenyl-p-benzoquinone (DPQ) and 2,6-diphenyl-p-hydroquinone (DPHQ). The NO2/Tenax TA reaction could be calibrated, thus the NO2 concentration could be determined simultaneously with a SVOC measurement. However, the results indicated that DPQ may be reduced to DPHQ during TD-GC analysis by oxidation of other compounds adsorbed to Tenax TA. Sampling an air mixture of O3 in excess of limonene on Tenax TA followed by TD-GC analysis exclusively produced DPHQ. O3 alone produced neither DPQ nor DPHQ. It was found that reactive species (possibly Criegee biradicals and/or other organic radicals) from the O3/limonene :reaction were responsible for the production of DPHQ from Tenax TA. The results indicated that Tenax TA can be used as a trapping agent for some radicals by analysis of the DPQ/DPHQ formation. The present data were not sufficient to obtain evidence for degradation of Tenax TA by other radicals than NO and NO2 in indoor SVOC samples. However, the DPQ/DPHQ ratio indicated that DPHQ has been formed from DPQ by oxidation of other adsorbed compounds in some of the samples.
An increasing number of researchers have hypothesized that ozone may be involved in the particle formation processes that occur during printing, however no studies have investigated this further. In the current study, this hypothesis was tested in a chamber study by adding supplemental ozone to the chamber after a print job without measurable ozone emissions. Subsequent particle number concentration and size distribution measurements showed that new particles were formed minutes after the addition of ozone. The results demonstrated that ozone did react with printer-generated volatile organic compounds (VOCs) to form secondary organic aerosols (SOAs). The hypothesis was further confirmed by the observation of correlations among VOCs, ozone, and particles concentrations during a print job with measurable ozone emissions. The potential particle precursors were identified by a number of furnace tests, which suggested that squalene and styrene were the most likely SOA precursors with respect to ozone. Overall, this study significantly improved scientific understanding of the formation mechanisms of printer-generated particles, and highlighted the possible SOA formation potential of unsaturated nonterpene organic compounds by ozone-initiated reactions in the indoor environment.
Exposure to emissions from laser printers during the printing process is commonplace worldwide, both in the home and workplace environment. In the present study, cytotoxic and genotoxic effects of the emission from five low to medium-throughput laser printers were investigated with respect to the release of ozone (O(3) ), volatile organic compounds (VOC), particulate matter (PM), and submicrometer particles (SMP) during standby and operation. Experiments were conducted in a 1 m(3) emission chamber connected to a Vitrocell® exposure system. Cytotoxicity was determined by the WST-1 assay and genotoxicity by the micronucleus test in human A549 lung cells. The five laser printers emitted varying but generally small amounts of O(3) , VOC, and PM. VOC emissions included 13 compounds with total VOC concentrations ranging from 95 to 280 μg/m(3) (e.g., 2-butanone, hexanal, m,p-xylene, and o-xylene). Mean PM concentrations were below 2.4 μg/m(3). SMP number concentration levels during standby ranged from 9 to 26 particles/cm(3). However, three of the printers generated a 90 to 16 × 10(3) -fold increase of SMP during the printing process (maximum 294,460 particles/cm(3)). Whereas none of the printer emissions were found to cause cytotoxicity, emissions from two printers induced formation of micronuclei (P < 0.001), thus providing evidence for genotoxicity. As yet, differences in biological activity cannot be explained on the basis of the specific emission characteristics of the different printers. Because laser printing technology is widely used, studies with additional cytogenetic endpoints are necessary to confirm the DNA-damaging potency and to identify emission components responsible for genotoxicity.
Processes involved in pollutant emissions from a dry-process photocopier have been investigated in a controlled room dynamic environmental chamber. Volatile organic compound (VOC) emissions occurred at a constant rate dependent on copy speed. However, VOC emission rates per copy were increased by increases in chamber temperature (e.g., a 20% increase resulted from increasing temperature from 23 degrees C to 32 degrees C) or changing from single- to double-sided operation (40% increase). Respirable particle emissions occurred under copier-idle mode (probably from residues in the machine) as well as with copying. No significant chamber sink effects were observed for VOCs or respirable particles. Small emissions of nitrogen dioxide, ozone and formaldehyde were observed but were difficult to interpret. A procedure for assessing pollutant emissions from photocopiers is recommended.
Personal and area samples from three copy centres were collected in thermal desorption tubes and analyzed using gas chromatography-mass spectrometry. Real-time personal total volatile organic compounds (TVOC) were measured using a data-logging photoionization detector. Fifty-four different VOCs were detected in the area samples. The maximum concentration measured was 1132.0 ppb (toluene, copy center 3, day 1). Thirty-eight VOCs were detected in the personal samples and concentrations ranged from 0.1 ppb (1,1-biphenyl, p-dichlorobenzene, propylbenzene, styrene, and tetrachloroethylene) to 689.6 ppb (toluene). Real-time TVOC measurements indicated daily fluctuations in exposure, ranging from <71 to 21,300 ppb. The time-weighted average exposures for the photocopier operators on days 1 and 2 were 235 and 266 ppb and 6155 and 3683 ppb, in copy centers 2 and 3, respectively. Personal exposure measurements of individual VOCs were below accepted occupational standards and guidelines. For example, the maximum concentration was 0.3% of the permissible exposure limits (toluene, copy center 3). Exposures were highest in copy center 3; this is likely due to the presence of offset printing presses. It is concluded that photocopiers contribute a wide variety of VOCs to the indoor air of photocopy centers; however, exposures are at least 100 times below established standards.
The question of whether perceived sensation correlates with medical tests was examined using data from the ProKlimA project (1994-1999) in which sensory perception and medical examination of Sick Building Syndrome related complaints were examined in 14 office buildings across Germany. Within the ProKlimA study, a subsample of 817 persons participated in ophthalmological examinations; dermatological tests were conducted on 925 persons using serni quantitative dermatological methods. Participants of both sub-samples responded to a questionnaire assessing sensory perception over 6 sub-scales (eyes, skin nose, mouth, throat and nervous systems) consisting of 9 to 11 items per sub-scale. Non-parametric analysis revealed a significant association between medical tests of symptoms and self-reported complaints regarding skin/eyes. Break up time, a measure of tear film stability, appeared to be the best indicator for self-reported eye complaints. In terms of skin symptoms, low sebaceous secretion and/or low stratum corneum hydration was associated significantly with increased skin complaints. But not all items of the sensory perception modules reflected the medical diagnoses in the same way. For instance the items "rough skin" and "dry skin" described the medical diagnosis "low sebum content" better than "irritated skin", "rash" or "spotty skin". However, sensory perception modules differed in their relationship to medical tests, so that questionnaires may be used as indicators not as substitutes for medical test data. The choice of method has to be determined by the purpose of the research project.
A literature review on studies in humans, applying physiological methods to monitor environmentally induced reactions in eyes and upper respiratory tract. The focus was on chemical exposures, but other occupational factors and indoor exposures were included.
Original articles were gathered from Medline until November 2000, combined with peer-reviewed publications from other sources.
Ocular methods included measurement of tear film break-up time (BUT), blink frequency, detection of corneal damage, by vital staining, and cells or inflammatory markers in tear fluid. Nasal methods included acoustic rhinometry, rhinostereometry, and nasal peak expiratory flow. In addition, nasal lavage with isotonic sodium chloride solution was applied to measure concentrations of leucocytes, or biomarkers of secretion or inflammation in nasal lavage fluid (NAL). Most occupational studies were on nasal effects of organic or inorganic dust. There were few studies on occupational exposure to organic solvents or chemical irritants. Some studies demonstrated associations between ocular and nasal physiological response and the indoor environment. Finally, there were some exposure-chamber studies on effects of specific volatile organic compounds (VOCs). Little is known about adaptation at repeated ocular or nasal exposure to irritants.
Physiological measurements can be valuable complements to symptom registration, but there is a need for standardised investigations. There is a lack of studies on ocular and nasal physiological responses in relation to specific chemical compounds. Experimental studies, with repeated exposure and longer follow-up time on biomarkers, are needed. Finally, there is a need for longitudinal epidemiological studies to elucidate if observed effects should be interpreted as variation within normal physiology, or as early signs of impaired ocular and respiratory health.
Unlabelled:
The population distributions of CO(2)-induced irritation sensitivity in the eyes (COI), tear film stability (break-up time, BUT), and epithelium damage (ED) and the relation of these to basic potential confounders were assessed in an age- and gender-stratified random sample of citizens in Aarhus County, Denmark. One hundred eighty-two non-allergic, non-smoking persons participated. A general health questionnaire and an indoor air questionnaire was filled out before the measurements. The BUT was non-normally distributed, as was COI at 16% CO(2) and single ED-scores. However, COI average for all levels was normally distributed and the total score for ED was only marginally deviating. BUT decreased, the threshold to CO(2) increased, and irritation intensity at CO(2) eye exposure decreased with increasing age. ED was increased among women. There were no internal relations between the three measures, but reduced BUT was seen among subjects rating high levels of exposure to dust, electrostatic fields, and dry air. ED decreased by perceived unpleasant odors and increased with experiences of high temperatures. CO(2) sensitivity increased by perceived draught, dry air, and noise exposure prior to measurements. Selection bias cannot be excluded and the results may therefore not be truly representative of the general population. However, the results may be used as reference data for future use of measurements of break-up time, epithelium defects, and CO(2) sensitivity of the eyes in the indoor air.
Practical implications:
The most direct implication is that results can be used as reference level for measurements in problem buildings and for individual measurements. The reference can also be used in research and the other results as basis for future hypotheses and for support of existing hypotheses.
Accurate assessment of upper respiratory tract and ocular irritation is critical for identifying and remedying problems related to overexposure to volatile chemicals, as well as for establishing parameters of irritation useful for regulatory purposes. This article (a) describes the basic anatomy and physiology of the human upper respiratory tract and ocular mucosae, (b) discusses how airborne chemicals induce irritative sensations, and (c) reviews practical means employed for assessing such phenomena, including psychophysical (e.g., threshold and suprathreshold perceptual measures), physiological (e.g., cardiovascular responses), electrophysiological (e.g., event-related potentials), and imaging (e.g., magnetic resonance imaging) techniques. Although traditionally animal models have been used as the first step in assessing such irritation, they are not addressed here since (a) there are numerous reviews available on this topic and (b) many rodents and rabbits are obligate nose breathers whose nasal passages differ considerably from those of humans, potentially limiting generalization of animal-based data to humans. A major goal of this compendium is to inform the reader of procedures for assessing irritation in humans and to provide information of value in the continued interpretation and development of empirical databases upon which future reasoned regulatory health decisions can be made. See full article at: http://escholarship.org/uc/item/2n70s9vx
To achieve a common base for understanding work related eye complaints in the office environment, it is necessary to merge approaches from indoor air science, occupational health, and ophthalmology. Based on database searches, it is concluded that precorneal tear film (PTF) alteration leads to eye complaints that may be caused by: (1) thermal factors (low relative humidity; high room temperature); (2) demanding task content (attention decreases blinking and widens the exposed ocular surface area); and (3) individual characteristics (for example, tear film alterations, blinking anomalies, gland dysfunctions, and use of contact lenses). These factors and conditions are able to progressively increase water evaporation and faster thinning of the PTF, which causes dryness and dry spot formation on the cornea, possibly followed by corneal and conjunctiva epithelial alterations and eye complaints. Another possible cause of eye complaints is certain irritating chemical compounds, in addition to oxidation mixtures that are formed in reactions between ozone and unsaturated organic compounds (alkenes). The effect may be exacerbated by low relative humidity.
Unlabelled:
Profiles of factors affecting self-reported eye symptoms and objectively determined tear film characteristics have been examined and compared using data from 814 office workers. Multiple logistic regression analysis reveals significantly increased risks of subjective perception of eye symptoms for female gender, use of contact lenses and persons with health problems. A reduced break-up time (BUT) depends on personal criteria such as a history of eye disease and female gender. Age under 40 years, high relative humidity and formaldehyde exposure exceeding the 90th percentile are protective regarding BUT. For a thin lipid layer (as an indication of dry eyes) significantly increased risks are detected for high particle load, high endotoxin concentration and female gender. A thick lipid layer (as an indication of inflamed eyes) is significantly associated with a low educational level. The estimation of foam in the medial eye canthus seems to be unsuitable for evaluating indoor problems. The risk factor profiles agree on a few points only. The objectively examined thin lipid layer is the best eye-related indicator of the indoor environment. We therefore conclude that there is a need for the development and application of objective clinical methods for field monitoring in parallel with questioning.
Practical implications:
Self-reported eye symptoms in conjunction with indoor environmental problems should be validated by objective medical examinations such as semi-quantitative estimation of the superficial lipid layer, measurement of the break-up time or assessment of conjunctival epithelial damage. For unbiased proof of environmental impact, personal factors such as acute illness or low job satisfaction should be excluded. As a minimum requirement, measurements of particles, NO(2) and relative humidity (and if possible endotoxin) should be carried out to detect any indoor environmental reason for eye symptoms.
ResearchGate has not been able to resolve any references for this publication.