TY - JOUR
T1 - Total mercury bias in soil analysis by CV-AFS
T2 - Causes, consequences and a simple solution based on sulfhydryl cotton fiber as a clean-up step
AU - Pérez, Pablo A.
AU - Bravo, Manuel A.
AU - Quiroz, Waldo
N1 - Funding Information:
The authors acknowledge the nancial support from Agencia Nacional de Investigación y Desarrollo (ANID). Pablo A. Perez also thanks CONICYT for doctoral and research-travel fellowships, as well as FONDECYT Post-Doc. 3190786. Moreover, we would like to special thank Dr Chris Harrod for his valuable suggestions on this manuscript.
Funding Information:
The authors acknowledge the financial support from Agencia Nacional de Investigación y Desarrollo (ANID). Pablo A. Perez also thanks CONICYT for doctoral and research-travel fellowships, as well as FONDECYT Post-Doc. 3190786. Moreover, we would like to special thank Dr Chris Harrod for his valuable suggestions on this manuscript.
Publisher Copyright:
© The Royal Society of Chemistry.
PY - 2020/8/7
Y1 - 2020/8/7
N2 - This study examines the matrix effect over the trueness for determining total mercury (THg) using CV-AFS. We demonstrate that matrix interferences in soils and sediment samples cannot be eliminated by acid digestion and establish the use of sulfhydryl cotton fiber (SCF), a malleable, cheap and easy to synthesize fiber, as a mandatory solution capable to overcome this bias. Using the classic CV-AFS approach, an overestimation bias for THg recovery values of >140% in a certified reference material was reported. Interference metals test was conducted, thus discarding any influence of metals in the overestimation bias. Therefore, a clean-up step using SCF was proposed, and tests with synthesized fiber did not present a dispersion of >0.08 ng L-1. Moreover, validation was performed by analyzing three certified reference material and yielding mean recovery percentages of 100% ± 1%. A validated methodology was applied to ten environmental soil samples; THg values obtained varied from 129 to 384 ng g-1. Finally, a comparison between sample results obtained and reference method did not show any significant differences (p > 0.05), thus highlighting the efficacy of SCF-CV-AFS for THg quantification in environmental solid samples.
AB - This study examines the matrix effect over the trueness for determining total mercury (THg) using CV-AFS. We demonstrate that matrix interferences in soils and sediment samples cannot be eliminated by acid digestion and establish the use of sulfhydryl cotton fiber (SCF), a malleable, cheap and easy to synthesize fiber, as a mandatory solution capable to overcome this bias. Using the classic CV-AFS approach, an overestimation bias for THg recovery values of >140% in a certified reference material was reported. Interference metals test was conducted, thus discarding any influence of metals in the overestimation bias. Therefore, a clean-up step using SCF was proposed, and tests with synthesized fiber did not present a dispersion of >0.08 ng L-1. Moreover, validation was performed by analyzing three certified reference material and yielding mean recovery percentages of 100% ± 1%. A validated methodology was applied to ten environmental soil samples; THg values obtained varied from 129 to 384 ng g-1. Finally, a comparison between sample results obtained and reference method did not show any significant differences (p > 0.05), thus highlighting the efficacy of SCF-CV-AFS for THg quantification in environmental solid samples.
UR - http://www.scopus.com/inward/record.url?scp=85089548412&partnerID=8YFLogxK
U2 - 10.1039/d0ay01035a
DO - 10.1039/d0ay01035a
M3 - Article
AN - SCOPUS:85089548412
VL - 12
SP - 3756
EP - 3762
JO - Analytical Methods
JF - Analytical Methods
SN - 1759-9660
IS - 29
ER -