Building materials represent the largest surfaces indoors and are the major contributors of volatile organic compounds (VOCs) in the indoor environment. This study which is conducted in the frame of BUMA project (Prioritization of Building Materials Emissions), aims at assessing the human exposure to air hazards emitted by building materials. In this study, indoor and outdoor VOCs and ozone measurements from field campaigns in two Mediterranean cities (Nicosia and Athens in winter period) are presented and discussed. The field campaigns concern weekly measurements. The campaigns were conducted in four buildings in each city (1 Public building, 1 school and 2 houses) and concern weekly measurements. Passive samplers were used for collecting VOCs and ozone. Eight (8) hydrocarbons (benzene, toluene, ethylbenzene, m,p-xylene, a-pinene, o-xylene and d-limonene), five (5) carbonyl compounds (formaldehyde, acetaldehyde, proprionaldehyde, acetone and hexanaldehyde) and ozone have been measured. Additional air exchange measurements have been conducted using tracer gas techniques. Hazardous substances such as benzene, formaldehyde and acetaldehyde present indoor concentrations that range between 1.5-10.2, 5.8-43.2 and 4.5-15 μg/m3, respectively. VOC concentration data show a considerable variability due to the different indoor emission sources, ventilation rates and outdoor environment's influence. A significant contribution to indoor measured concentrations seems to come from the building materials. Ozone outdoor concentrations are reduced substantially inside, indicating relatively strong indoor ozone sinks

Barero-Moreno, Josefa M.

Bartzis, John G.

Kotzias, Dimitrios

Michael, Costas

Michaelidou, Stella

Missia, Dafni A.

Petaloti, Christine

Psoma, S.

Saraga, Dikaia E.

Tolis, Evangelos I.

English

Open Research Online (The Open University)

Open Research OnlineThe Open University’s repository of research publicationsand other research outputsConcentrations of VOCs and ozone in indoorenvironments: A case study in two Mediterraneancities during winter periodJournal ItemHow to cite:Bartzis, John G.; Michael, Costas; Michaelidou, Stella; Missia, Dafni A.; Saraga, Dikaia E.; Tolis, EvangelosI.; Psoma, S.; Petaloti, Christine; Kotzias, Dimitrios and Barero-Moreno, Josefa M. (2008). Concentrations ofVOCs and ozone in indoor environments: A case study in two Mediterranean cities during winter period. FreseniusEnvironmental Bulletin, 17(9b) pp. 1480–1484.For guidance on citations see FAQs.c© [not recorded]Version: Version of RecordCopyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyrightowners. For more information on Open Research Online’s data policy on reuse of materials please consult the policiespage.oro.open.ac.uk© by PSP Volume 17  No 9b. 2008   Fresenius Environmental Bulletin    1480 CONCENTRATIONS OF VOCS AND OZONE  IN INDOOR ENVIRONMENTS: A CASE STUDY IN  TWO MEDITERANEAN CITIES DURING WINTER PERIOD John G. Bartzis1*, Costas Michael2, Stella Michaelidou2, Dafni A. Missia1, Dikaia E. Saraga3,  Evangelos I. Tolis1, S. Psoma1, Christine Petaloti1, Dimitrios Kotzias4 and Josefa M. Barero-Moreno4 1University of West Macedonia, Dept. of Eng.& Manag. of Energy Resources, Sialvera & Bakola Street, 50100 Kozani, Greece  2State General Laboratory, Section of Environmental Chemistry, Pesticides,  Ecotoxicology and Radioactivity, 44 Kimonos Street, 1451 Nicosia, Cyprus 3Environmental Research Laboratory, Institute of Nuclear Technology -  Radiation Protection, NCSR "DEMOKRITOS", 15310 Aghia Paraskevi Attikis, Athens, Greece 4Joint Research Centre (JRC), Institute for Health and Consumer Protection, TP. 260, 21020 Ispra (VA) Italy Presented at the 14th International Symposium on Environmental Pollution and  its Impact on Life in the Mediterranean Region (MESAEP), Sevilla, Spain, 10  14 Oct. 2007 ABSTRACT Building materials represent the largest surfaces in-doors and are the major contributors of volatile organic compounds (VOCs) in the indoor environment. This study which is conducted in the frame of BUMA project (Priori-tization of Building Materials Emissions), aims at assessing the human exposure to air hazards emitted by building materials. In this study, indoor and outdoor VOCs and ozone measurements from field campaigns in two Mediter-ranean cities (Nicosia and Athens in winter period) are presented and discussed. The field campaigns concern weekly measurements. The campaigns were conducted in four buildings in each city (1 Public building, 1 school and 2 houses) and concern weekly measurements. Passive sam-plers were used for collecting VOCs and ozone.  Eight (8) hydrocarbons (benzene, toluene, ethylben-zene, m,p-xylene, a-pinene, o-xylene and d-limonene), five (5) carbonyl compounds (formaldehyde, acetaldehyde, pro-prionaldehyde, acetone and hexanaldehyde) and ozone have been measured. Additional air exchange measurements have been conducted using tracer gas techniques. Hazardous sub-stances such as benzene, formaldehyde and acetaldehyde present indoor concentrations that range between 1.510.2, 5.8-43.2 and 4.5  15 µg/m3, respectively. VOC concen-tration data show a considerable variability due to the dif-ferent indoor emission sources, ventilation rates and outdoor environments influence. A significant contribution to in-door measured concentrations seems to come from the building materials. Ozone outdoor concentrations are re-duced substantially inside, indicating relatively strong in-door ozone sinks. KEYWORDS: Indoor air quality, VOCs, formaldehyde, passive sampling, ozone INTRODUCTION It is a fact that people spend on average 90% of their life indoors, and during the last decades, great concern has been focused on the adverse health effects that may be caused by significant indoor pollutant concentrations. Both indoor and outdoor sources contribute to the development of pollutants concentration and composition profiles in an internal environment. Ventilation plays a crucial role for estimating and evaluating the levels of pollution and its contingent source. Many inorganic and organic compounds have identified in indoor air. Among these, VOCs and ozone comprise a group of pollutants that gained particu-larly significant attention due to their various sources and their harmful effects on humans (carcinogenicity, irrita-tions etc).  VOCs that commonly detected in indoor air are ali-phatic hydrocarbons, benzene and alkylated aromatic hy-drocarbons, chlorinated hydrocarbons as well as aldehydes, ketones, and alcohols [1]. For many of these chemicals, the risk on human health and comfort is almost unknown and difficult to predict because of lack of toxicological data. In the frame of INDEX project the existing knowledge world-wide has been assessed on type and levels of chemicals in indoor air as well as the available toxicological information. © by PSP Volume 17  No 9b. 2008   Fresenius Environmental Bulletin    1481 Thus, INDEX Project concluded in a priority ranking of 14 chemicals assigned to three groups [2].  Indoor ozone, which originates from both indoor (pho-tocopiers and other machines) and outdoor (ventilation and infiltration systems) sources, is a common highly reactive oxidizing agent in indoor environment [3]. Ozone concen-trations could be high enough to drive chemical reactions with monoterpenes and form ultrafine particles and irritat-ing gaseous organic compounds [4].  This study was conducted in the framework of a Euro-pean project partly funded by PHEA (Public Health Ex-ecutive Agency), called Prioritization of Building Materi-als Emissions (BUMA). The aim of the present work is the evaluation of the indoor and outdoor air quality, regard-ing VOCs and ozone, at Nicosia, Cyprus and Athens, Greece, focusing on organic compounds that belong to the first two priority groups of INDEX Project, such as ben-zene, formaldehyde, toluene, xylenes, and acetaldehyde.  MATERIALS AND METHODS This study was carried out in 2007, from 9th to 16th of February and 8th to 15th of March for Nicosia and Athens, respectively. Measurements were conducted simul-taneously in four buildings in order to evaluate the indoor VOCs and ozone levels. The study plan firstly included the selection of the buildings in which passive samplers were installed. The buildings employed in the present study were selected according to the following criteria: (1) the age of the building (2) the last reconstruction or renovation, as far as (3) the position (urban sites preferred) of the building. The main characteristics of the selected buildings summa-rized in Table 1. The buildings are four in every case, one public building, one school and two private houses. In addi-tion, for indoor temperature and relative humidity (RH) measurements data loggers (HOBO H-8 onset) were used. Finally, ventilation measurements were conducted using tracer gas technique.  Moreover, questionnaires were filled in, giving valu-able information regarding the sampling sites and activities taken place during sampling. At indoor locations, the pas-sive sampling equipment was placed on sites on the wall approximately 1.5 m above the ground. Outdoor sampling locations were chosen to avoid significant point sources of pollution, such as building exhaust vents.  Indoor and outdoor measurements of BTEX, carbon-yls and ozone were conducted using passive samplers named Radiello in each tested room and outside for one week. The samplers used for BTEX was Activated Char-coal Cartridges, CS2-desorption for GC-Analysis (code 130), for Aldehydes DNPH-covered cartridges, acetonitrile de-sorption for HPLC-VIS (code 165) and for ozone 1, 2- di- (4-pyridyl) - ethylene covered cartridges for MBTH (3-Methyl - 2-Benzothiazolinone Hydrazone) solution desorp-tion, UV-VIS (code 172). The analysis of BTEX was car-ried out by GC/FID after desorption of the analytes with CS2 and included determination of benzene, toluene, xy-lenes, ethylbenzene, 1,2,4 trimethylbenzene, d-limonene, a-pinene. The determination of all analytes was confirmed by GC-MS. The analysis of carbonyls and ketones was carried out using HPLC-VIS after desorption of the analytes with acetonitrile and included determination of formalde-hyde, acetaldehyde, acetone, propanal and hexanal. The analysis of ozone was conducted using spectrophotometer-VIS after desorption with (MBTH) solution. The analysis of the samples was conducted in the State General Labo-ratory (SGL) of Cyprus. With tracer gas technique, air exchange rates were es-timated using NORDTEST METHOD NT VVS 118. This method can be used in types of buildings, dwellings, offices, schools etc. The testing of ventilation is performed by using homogeneous emission of tracer gas at a constant rate in the ventilated system and subsequent analysis of the steady state concentration of that tracer gas in different parts of the system [5]. TABLE 1 - Main characteristics of selected buildings. Nicosia Public Building School/Kindergarten House 1 House 2 Location City, heavy traffic City, calm area, light traffic Suburban, calm area, light traffic Suburban area, No traffic Building Status A newly constructed building (2007) No human activity New paint in 2005 New paint three (3) months ago. New furnishing in 2004 No major renovation. No human activity for three (3) days Specific air flow rate (ACH)(h-1) 1.28 0.62 0.51 1.1 Athens Public Building School/Kindergarten House 1 House 2 Location Suburban area, light traffic Suburban area, light traffic Suburban area, light traffic Suburban area, light traffic Building status New paint, furnishing and flooring in 2004 New paint in 2006 Constructed in 2005 New paint, flooring and fur-nishing in 2006. Smoking Specific air flow rate (ACH) (h-1) 0.41 0.4 0.24 0.28 © by PSP Volume 17  No 9b. 2008   Fresenius Environmental Bulletin    1482 RESULTS AND DISCUSSION VOCs. Summary statistics for the concentrations of all measured compounds in indoor air are given in Table 2. The most prevalent VOCs in buildings were toluene, xy-lenes, a-pinene, formaldehyde and hexanaldehyde. Indoor concentrations usually exceeded outdoor levels. Priority compounds constituted large proportion of sum of VOCs in Nicosia and Athens schools, respectively, (Figure 1) greater than those reported in Michigan classrooms. Moreover, VOCs concentrations tended to differ significantly between elementary (Nicosia) and middle schools (Athens) as it has been observed in similar studies at Michigan schools [6].  Reported public buildings indoor concentrations of individual VOCs are generally below 50 µg/m3 except for toluene and m,p- xylene in Nicosia public building. Lev-els of VOCs in Nicosias office is much greater than those observed in Athens due to its age (newly constructed and not occupied until and during the sampling period). Mean concentrations of the majority of VOCs in both cities are below 10 µg/m3, a common trend for both European and American countries [7]. However, new furnishing, renova-tion of some of the selected buildings or indoor human activities may result in temporarily higher concentrations e.g. Nicosias public building and Athens selected houses. High VOCs and O3 concentrations in Athens houses can be  TABLE 2 - Average indoor measured concentrations of VOCs and ozone in all buildings (µg/m3).  Public Buildings Schools Houses  Athens Nicosia Athens Nicosia Athens Nicosia Benzene 1.6 ND* 2.4 4.5 6.4 2.6 Toluene 3.4 66.4 4.6 20.4 53.9 9 Ethylbenzene 0.8 25.6 0.8 1.9 13.4 1 m,p- xylene 1.8 110.3 2.3 5.3 55.6 4.5 o-xylene 0.8 27.8 0.9 2.3 14.2 1.6 a-pinene 1.2 24.3 2.1 1.7 22.2 3.1 1,2,4- TMB 1.1 7.5 1.4 4.8 5.4 2.3 d-limonene 2.6 3.5 2.3 24.1 43.5 9.4 Formaldehyde 11.1 24.2 6.3 21 28.8 16.8 Acetaldehyde 5.7 7.8 4.6 12.2 13.2 5.7 Acetone 26.7 39.9 11.9 24.5 56.5 106.7 Proprionaldehyde 2.6 5 1.9 2.5 4.7 2.7 Hexanaldehyde 17 35.9 6.8 14 41 13.7 Ozone 7.6 1.7 13.9 1.1 1.7 4.6 * ND: Non detected 0% 20% 40% 60% 80% 100%AthensNicosiaAthensNicosiaAthensNicosiaPublic BuildingSchoolHousesHigh priority compoundsOther compoundsFIGURE 1 - Average percentage of sums of high priority compounds in selected buildings. © by PSP Volume 17  No 9b. 2008   Fresenius Environmental Bulletin    1483 TABLE 3 - Indoor to Outdoor ratios in public buildings.  Athens Nicosia Benzene  1.2 - Toluene 1.2 4.3 Ethylbenzene 1.3 9.4 m,p-xylenes 1.2 13.5 o-xylene 1.1 8.6 1,2,4- trimethylbenzene 1.2 1.1 a-pinene 2.9 4.7 d-limonene - 3.9 Formaldehyde 5.8 5.8 Acetaldehyde 3.2 3.5 Acetone 4.6 10.9 Proprionaldehyde 2.8 4.1 Hexanaldehyde 8.5 15.6 Ozone 0.1 0.03 attributed to the low air exchange rates (0.28 and 0.24 h-1), as it is obtained from the ventilation measurements results. Acetaldehyde and hexanaldehyde levels are lower than those found for private houses in Paris [8]. Such observa-tions suggest probably the absence of indoor sources for acetaldehyde since acetaldehyde is mainly emitted from combustion processes. Propionaldehyde concentrations in houses were measured greater than those found in private houses [9]. The levels of formaldehyde did not exceed the WHO guideline value of 100 µg/m3, which may cause nose and throat irritation in humans after short-term exposure [10]. Formaldehyde in Athens school exhibited the same levels observed in the same type of schools at Uppsala City [11] in contrast to Nicosia schools which presented greater concentrations due to the pupils activities indoors (paint-ing with markers etc.) and shown greater concentrations than schools in Shangai, China [12]. It is worth to notice that concerning priority com-pounds, except for benzene, indoor to outdoor ratios (I/O) in public buildings (Table 3) are substantially greater than unity (>1) suggesting important indoor sources for these VOCs. More specifically, for hexanaldehyde I/O ratio is up to 15.6, for m,p-xylene 13.5, for acetone 10.9, and for for-maldehyde 5.8.  Ozone. The importance of measuring ozone in indoor environments comes from its ability to react with high mo-lecular organic compounds and specifically with terpenes forming ultrafine particles and free radicals. As it is ob-served, outdoor concentrations are significantly higher in contrast with indoor levels. The indoor to outdoor ozone concentration ratio generally ranged between 0.2 and 0.7 indicating ozone  indoor chemistry relationship as men-tioned by Nicolas et al [13]. Thus, for Nicosias office, the I/O ratio, in combination with the occupants absence inside the building, indicates that there are no strong in-door sources of ozone. In contrary, the indication is that there exist strong sinks of ozone indoors.  CONCLUSIONS The concentration data show a considerable diversity due to the different indoor emission sources, ventilation rates and outdoor environments concentrations. Benzene, formaldehyde and acetaldehyde levels in public buildings are lower than those expected in indoor environments. The sum of priority compounds consist a large proportion of the sum of VOC in all selected buildings. The relatively high I/O ratios indicate strong indoor emissions sources except for benzene. Ozone outdoor concentrations seem to be re-duced substantially inside; indicating relatively strong in-door ozone sinks.  ACKNOWLEDGMENT BUMA project is funded by the European Commu-nity, Public Health Executive Agency (PHEA). REFERENCES [1] Baya, M.P., Bakeas, E.B. and Siskos, P.A. (2004) Volatile Organic Compounds in the air of 25 Greek homes. Indoor Built Environment 13, 53-61.  [2] Kotzias, D., Koistinen, K., Kephalopoulos, S., Schlitt, C., Carrer, C., Maroni, M., Jantunen, M., Cochet, C., Kirchner, S., Lindvall, T., McLaughlin, J., Mølhave, L., Fernandes, O.E. and Seifert, B. (2005) The INDEX project. Critical ap-praisal of the setting and implementation of indoor exposure limits in the EU. Final Report.  [3] Weschler, C.J., Hodson, A.T. and Wooley, J.D. (1992) In-door chemistry: ozone, volatile organic compounds and car-pets. Environmental Science and Technology 26, 2371- 2377.  [4] Molhave, L., Kjaergaad, S.K., Sigsgaard, T. and Lebowitz, M. (2005) Interaction between ozone and airborne particulate matter in office air. Indoor Air 15, 383-392.  [5] NORDTEST METHOD NT VVS 105 (1994). Ventilation: Flow rate, total effective  by single zone approximation.  © by PSP Volume 17  No 9b. 2008   Fresenius Environmental Bulletin    1484 [6] Godwin, C. and Batterman, S. (2007) Indoor air quality in Michigan schools. Indoor Air 17, 109  121.  [7] Wolkoff, P., Wilkins, C.K., Clausen, P.A. and Nielsen, G.D. (2006) Organic Compounds in office environments  sensory irritation, odor, measurements and the role of reactive chem-istry. Indoor Air 17, 7-19. [8] Clarrise, B., Laurent, A.M., Seta, N., Moullec, Y., Hasnaoui, A. and Momas, I. (2003) Indoor aldehydes: Measurements of contamination levels and identification of their determinants in Paris dwellings. Environmental Research 92, 245- 253.  [9] Marchand, C., Bulliot, B., Calve, S. and Mirable, Ph. (2006) Aldehyde measurements in indoor environments in Stras-bourg (France). Atmosheric Environment 40, 1336- 1345.  [10] WHO (2001). World Health Organization, Air quality guide-lines for Europe 2000. WHO Regional Office for Europe. [11] Kim, J.L., Elfman, L., Mi, Y., Wieslander, G., Smedje, G. and Norback, D. (2007) Indoor molds, bacteria, microbial volatile organic compounds and plastisizers in schools  as-sociations with asthma and respiratory symptoms in pupil. Indoor Air 17, 153  163.  [12] Mi, Y.H., Norback, D., Tao, J., Mi, Y.L. and Ferm, M. (2006) Current asthma and respiratory symptoms among pu-pils in Shangai, China: influence of building ventilation, ni-trogen dioxide, ozone and formaldehyde in classrooms. In-door Air 16, 454  464.  [13] Nicolas, M., Ramalho, O. and Maupetit, F. (2007) Reactions between ozone and building products: Impact on primary and secondary emissions. Atmospheric Environment 41, 3129  3138.  Received: December 19, 2007 Accepted: February 12, 2008 CORRESPONDING AUTHOR John G. Bartzis University of West Macedonia Department of Engineering and  Management of Energy Resources Sialvera & Bacola Str.  50100 Kozani GREECE Phone: +302461056620 Fax: +302461021730 E-mail: bartzis@uowm.gr   FEB/ Vol 17/ No 9b/ 2008  pages 1480 - 1484 View publication stats

Concentrations of VOCs and ozone in indoor environments: A case study in two Mediterranean cities during winter period

Concentrations of VOCs and ozone in indoor environments: A case study in two Mediterranean cities during winter period

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