Field Sampling and Determination of Formaldehyde in Indoor Air with Solid-Phase Microextraction and On-Fiber Derivatization

Abstract

A new sampling and analysis method for formaldehyde in indoor air was tested in several indoor air surveys. The method was based on the use of solid-phase microextraction (SPME) poly(dimethylsiloxane)/divinylbenzene,65-microm fiber and gas chromatography. Indoor air surveys included grab and time-weighted average (TWA) sampling and were completed at six locations using (a) the SPME method employing on-fiber formaldehyde derivatization with o-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride and (b)the conventional National Institute for Occupational Safety and Health (NIOSH) 2451 method. Sampling time for SPME fiber ranged from 10 min for grab sampling to 8 h for TWA sampling. Sampling locations included a residential house, a rental apartment, an office building, and industrial workplaces. The air concentrations measured by SPME ranged from 10 to 380 ppbv and correlated well with those estimated by the NIOSH method. Results also indicated thatin some cases the formaldehyde concentrations measured in residential air could be much higher than those allowed in occupational settings. The SPME method proved to be accurate, fast, sensitive, and cost-efficient in field sampling applications. This research should be of interest to research, industrial, and regulatory agencies as well as to the general public concerned with indoor air quality.

Determination of thiol compounds by automated headspace solid‐phase microextraction with in‐fiber derivatization

“…[27][28][29] The simplest way to carry out this process is to dope the fiber with a derivatization reagent and expose it to the sample. Then, the analytes are extracted and converted to derivatives that exhibit a high affinity for the coating ( Figure 1).…”

“…The agitation speed was set at 500 rpm for the loading of the derivatization reagent in order to accelerate the transfer of the reagent onto the SPME fiber coating. Based on the results of similar experiments, [27][28][29] 50°C and 1 h were adopted as the temperature and time for HS-SPME extraction. The results of the screening illustrated that, of all the commercially available SPME fibers, PDMS-DVB fiber had the best extraction performance for the N-phenylmaleimide derivatives over the rest of the fibers (Figure 2).…”

Compostos carbonílicos atmosféricos: fontes, reatividade, níveis de concentração e efeitos toxicológicos

“…Os níveis de concentração de aldeídos em ambientes internos são, na maioria das vezes, maiores quando comparados com ambientes externos 1,69,75 . Por exemplo, os resultados obtidos por Brickus e colaboradores 75 , para um edifício de escritório no Rio de Janeiro, apresentaram uma razão média de concentração interna/externa de 2,6 para formaldeído e, 1,3 para acetaldeído.…”

Determination of formaldehyde in shiitake mushroom by ionic liquid-based liquid-phase microextraction coupled with liquid chromatography

“…Briefly, 10 l of [C 8 MIM][PF 6 ] was withdrawn into a 50 l microsyringe (Agilent), and the microsyringe was clamped into place such that the needle of the syringe was immersed into the 5 ml sample solution held in a vial, then a 10 l of [C 8 MIM][PF 6 ] drop was exposed to the sample by depressing the plunger and the magnetic stirrer was turned on. After stirring for the prescribed time, the [C 8 …”

“…In recent years, chromatographic methods including GC [6,7] and HPLC [9][10][11] have been the most frequently reported one for the determination of formaldehyde. The most commonly used sample preparation procedure for chromatographic determination of formaldehyde is based on its reaction with 2,4-dinitrophenylhydrazine (DNPH) to form the corresponding hydrazone (DNPHo), which is extracted by liquid-liquid extraction [12], solid-phase extraction [11] or solid-phase microextraction [7,8]. Although the DNPH derivation method has relatively good selectivity, extraction is commonly used as sample clean-up procedure before chromatographic separation [14].…”