Alkyllead compounds in surface and potable waters

Abstract

Gas chromatography/atomic absorption spectrometry was used to determine specific alkyllead compounds in surface and potable water samples. For the first time ionic alkyllead species were identified in potable waters at very low levels with concentrations up to 4 ng Pb 1 -1 . No tetraalkyllead compounds were found in any of the samples analysed and laboratory studies demonstrated that these species decompose rapidly in aqueous samples to trialkyl lead, the most common form of organic lead in environmental samples.

Seasonal variation of the ionic alkyllead species composition of rainwater

“…We did not, however, monitor systematically the tetraalkyllead species in the samples; some of them, including unfiltered and freshly collected rain after showers, were preextracted with hexane, and no TAL compounds were detected in the extract using GC-AAS, with detection limits around 20 ng L'1 Pb. Moreover none of the numerous natural water samples investigated so far by several groups was found to contain tetraalkyllead (16,(20)(21)(22), with claimed detection limits for hexane-extractable lead as low as 1 ng L"1 Pb, except for a report that demonstrated occasional TAL contents in rain of up to ca. 90 ng L'1 Pb (23).…”

Atmospheric speciation and wet deposition of alkyllead compounds

“…Recent measurements of alkyllead compounds in rainwater suggest that wet deposition processes (rainout/washout) may be an important removal mechanism of these pollutants from the atmosphere and a source of these species in surface waters (5)(6)(7)(8). Alkyllead species released into the atmosphere may therefore enter into other environmental reservoirs via the hydrological cycle and have been identified at very low levels in potable water (9). Damage to German forests has recently been attributed to R3Pb+ compounds in rainwater (10), but high concentrations measured in the latter study with a nonspecific biochemical technique have been disputed on the basis of measurements made by using species-specific gas chromatograf Present address: Department of Chemistry, UMIST, Manchester, U.K. phy/atomic absorption spectroscopy (GC/AAS) (7).…”

Organolead speciation in environmental samples: a review

“…Derivatization modifies part of the molecule to render it more volatile without changing the original structure of the alkyl groups bonded to the lead atom, thus preserving the authenticity of the original compounds. As Grignard reagents, generally propyl- [3,16,54,55,57], butyl- [15,51,52,57,[67][68][69][70], pentyl- [57,71] and phenylmagnesium chloride [59] were proposed. The latter results, however, in less volatile derivatives, which lengthen and degrade the chromatographic separation, and was found to induce the formation of a large number of artifacts during derivatization [72].…”

“…Elution with acetate buffer + CH3OH. HPLC-photometry R 3Pb + rainwater [11] rain and tap water [15] polar snow [3,16], tap water [72] surface [8], lake, river [51], rain water [52] river, lake surface water [54] water [58,59] rainwater [70] drinking, harbour and rain water [79,80] " QT---quartz t~zbe. b R = Me or Et.…”

“…Both packed and capillary columns have been used. Packed columns usually filled with Chromosorb W containing a 3-10% loading of OV-101 [8, 13,37,46,52,54,55] or Carbowax [201 are the most widely used. They can be conveniently cleaned and have large sample capacity.…”