Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Biomonitoring of lead in Antarctic lichens using laser ablation inductively coupled plasma mass spectrometry

Full text
Author(s):
Guerra, Marcelo B. B. [1, 2] ; Amarasiriwardena, Dulasiri [2] ; Schaefer, Carlos E. G. R. [3] ; Pereira, Catarinie D. [1] ; Spielmann, Adriano A. [4] ; Nobrega, Joaquim A. [1] ; Pereira-Filho, Edenir R. [1]
Total Authors: 7
Affiliation:
[1] Univ Fed Sao Carlos, UFSCar, Grp Appl Instrumental Anal, Dept Chem, BR-13565905 Sao Carlos, SP - Brazil
[2] Hampshire Coll, Sch Nat Sci, Amherst, MA 01002 - USA
[3] Univ Fed Vicosa, Dept Soil Sci, UFV, BR-36570000 Vicosa, MG - Brazil
[4] Univ Fed Mato Grosso do Sul, UFMS, BR-79080190 Campo Grande, MS - Brazil
Total Affiliations: 4
Document type: Journal article
Source: Journal of Analytical Atomic Spectrometry; v. 26, n. 11, p. 2238-2246, 2011.
Web of Science Citations: 14
Abstract

A method for direct determination of Pb by LA-ICP-MS in lichen samples collected in a heavily anthropogenically impacted area of Maritime Antarctica was developed. The lichen samples were cryogenically ground and digested with nitric acid and hydrogen peroxide. Lead determination by solution-based ICP-MS was validated by the use of 2 certified reference materials. Once the Pb concentrations were measured with adequate accuracy and precision, a method for its direct determination by LA-ICP-MS was developed. The laser ablation parameters were optimized by the use of a Doehlert design matrix. The final optimized conditions were: laser energy (60%), spot size (150 mu m) and repetition rate (10 Hz). Lead concentration of the analyzed lichen samples were plotted against the intensity of the lead isotopes ((208)Pb, (207)Pb and (206)Pb) determined by LA-ICP-MS. Satisfactory linear correlation factors were obtained when (13)C was used as internal standard. Lead distribution profiles in lichen thalli cross-sections were also obtained. By these results, LA-ICP-MS emerges as a potential analytical tool for Pb concentration estimation in lichen samples. Minimum amount of sample required, bioimaging capability, high analytical throughput, and minimization of waste generation are the major analytical features of this approach. The significant differences between the Pb concentration in the lichen samples from the control site (1.12 +/- 0.05 mg kg(-1)) and from the impacted points (mean 5.03 +/- 0.57 mg kg(-1)) permitted qualify these organisms as good biomonitors. Elemental bioimaging of lichens demonstrated that the medulla region of lichen thalli is consistently the main atmospheric lead bioaccumulating lichen tissue. (AU)

FAPESP's process: 08/08260-3 - Chemical analyses of environmental samples from Antartica: spectrometric determination of Cd, Cr, Ni and Pb, use of micro X-Ray fluorescence with synchrotron radiation and application of chemometric tools
Grantee:Marcelo Braga Bueno Guerra
Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
FAPESP's process: 06/59083-9 - Inductively coupled plasma mass spectrometry: fundamentals and applications
Grantee:Joaquim de Araújo Nóbrega
Support Opportunities: Research Projects - Thematic Grants