Determination of the speciation of organolead compounds in airborne particulate matter by gas chromatography-inductively coupled plasma mass spectrometry

The speciation of organolead compounds in airborne particulate matter was d etermined by gas chromatography-inductively coupled plasma mass spectrometr y. The analytes were extracted from the sample using 0.5 M acetic acid in m ethanol. The ionic organolead compounds were extracted into hexane using di ethydithiocarbamate at pH 9 in the presence of EDTA to complex inorganic Pb . Derivatisation of the organolead species was performed with butylmagnesiu m chloride. Separation and detection of the butylated trimethyllead (TML), dimethyllead (DML), triethyllead (TEL) and diethyllead (DEL) was achieved. Detection limits, as Ph, were 3.2 fg for TML, 2.4 fg for DML, 1.8 fg for TE L and 9 fg for DEL for a 1 mu l sample injection. Typical precision of repe titive injections was 1.5-4% using tetraethyllead (TrEL) as internal standa rd. The method proposed was validated by the determination of TML in the re ference material CRM 605 and was applied to the analysis of airborne partic ulate matter in the atmosphere of the city of Oviedo. DML, DEL and methylet hyllead (MEL) were detected at pg m(-3) levels. (C) 2000 Elsevier Science B .V. All rights reserved.