CONSTRUCTION OF A LOW COST AIR SAMPLER AND IT'S APPLICATION IN SAMPLING VOLATILE CARBONYL COMPOUNDS

Abstract

lntcrcxt is expanding in measuring. concentrations of volatile organic compounds inbuildings since it is rccogniscd that many peoples' exposure to these compounds occur inthe indoor environment. However. such data are not available in Sri Lanka primarily dueto lack 01"proper equipment for quantitation and their high maintenance cost. This paperdcxcribcx the construction of a low cost air sampler (Rs. 40()/=) using commonly availablematerials.

The air sampler contains a muffler fan to pull .unhient air though a filrcrts) and/or a bed ofsorhcnt material. which are housed in a variable length pye tube. Battery poweredmuffler fan and lightweight are two of the convenient features of this air sampler thatminimisc operational and transportation difficulties to the user.

Vularilc carbonyl compounds such as formaldehyde acetaldehyde and acetone arecommonly found in indoors ambient air due to the combustion sources and emissions fromsvnthcric household products. Since formaldehyde is a known carcinogen andacetaldehyde is a suspected carcinogen compound. they were selected as the modelcompounds for the evaluation of constructed sampler. A filter paper spiked with 2. 4-dinitrophcnylhydruzcnc is used to collect the airborne carbonyl compounds at a flow rate ofI.X Cill'/SCC. Filters were sonicated in methanol and extracts were separated using a C,xcolumn for qu.uuitation at lSO mm wavelength. Quanutaiion limits estimates thats.unpling of I () dm ' ambient air enables minimum quantitauon of O.S formaldehyde. 1.0acetaldehyde and 1.2 acetone accurately. The paper also reports quantified levels ofairborne carbonyls from different indoor environments.