![]() 2001) or thermodesorption and gas chromatography detection (Ho and Yu 2002). 2004), 2.3.4.5.6-PENTAFLUOROBENZYLHYDROXYLAMINE derivatization followed by solid-phase micro-extraction (Koziel et al. 2007), Fluoral-P derivatization which is formaldehyde specific and UV detection (Pinheiro et al. Many other derivatisation agents have been tested on other sampling medium such as passive sampling based on CENT ( O-(4-cyano-2-ethoxybenzyl) hydroxylamine) (Onishi et al. It has been compared with DNPH active sampling by Salthammer and Mentese 2008 who have shown a good agreement between both techniques for formaldehyde measurement. Another standard procedure (Nash 1953), the acetyl acetone method based on the Hantzsch reaction is also widely applied. 2006 Huynh and Vu-Duc 2002 Marchand et al. They are widely used for formaldehyde measurement (Andreini et al. Both are based on the reaction of the carbonyl function with 2.4-dinitrophenylhydrazine (DNPH) to form an UV emitting chromophore, hydrazone. Therefore many techniques have been developed for formaldehyde measurements and among them indirect methods, based on formaldehyde derivatization, for concentration monitoring and population exposure survey and on-line continuous methods for source emissions and concentration variation monitoring.Īs for indirect method, there are two international standards methods for formaldehyde measurement in indoor environments, respectively, for active sampling (ISO 16000-3: 2001, 2001) and passive sampling (ISO 16000-4:2001, 2004). Since people spend most of the time in indoor environments, it is essential to be provided with reliable and accurate analytical techniques to assess their exposure to formaldehyde. In French dwellings, average formaldehyde levels vary from 3 to 60 μg m −3 (Observatory on Indoor Air Quality (OQAI) 2006). Usually much higher than outdoor concentrations, indoor formaldehyde levels can consequently reach rather high values like 125 μg m −3 in residential environments (Zhang et al. 2008) which are widely used in domestic cleaning products and air fresheners (Nazaroff and Weschler 2004). Formaldehyde can also be formed as a secondary product from volatile organic compounds oxidation such as terpenes (Bonn et al. ![]() 2006) or intermittent such as cigarette smoke and combustion processes. These sources can be either continuous like resins used for wood manufacture products (Brown 1999 Loh et al. An overall agreement between each technique has been observed and continuous analyzers allowed for formaldehyde concentrations change monitoring and secondary formation of that pollutant observation.įormaldehyde is one of the major indoor air pollutants due to its human health effects, it has been classified in group 1 (human carcinogen) by the International Agency for Research on Cancer (IARC 2004), and its various emission sources. The analytical and sampling problems associated with each measurement method have been identified and discussed. The real atmosphere experiments have been performed in four different indoor environments: an office, a furniture shop, a shopping mall, and residential dwellings in which several potential formaldehyde sources linked to household activities have been tested. Influence of sampling periods on passive sampling has also been evaluated. ![]() Two formaldehyde concentrations, about 10 and 25 μg m −3 were generated in an exposure chamber under controlled conditions of temperature, relative humidity, and wind speed to simulate real conditions and assess potential influence on passive sampling and continuous systems response. In the present work, four different techniques have been tested in the INERIS exposure chamber and in indoor environments in comparison to a standard active method: passive sampling method based on the reaction of 2,4-dinitrophenylhydrazine with formaldehyde, two on-line continuous monitoring systems based on fluorescence and UV measurements and a portable commercialised analyser based on electrochemical titration. Therefore, it is important to have suitable methods and techniques to measure its content in indoor air. ![]() Formaldehyde is of particular health concern since it is carcinogenic for human and ubiquitous in indoor air where people spend most of their time.
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