High-Precision Measurements of the Isotopic Composition of Common Lead Using MC-ICPMS: Comparison of Calibration Strategies Based on Full Gravimetric Isotope Mixture and Regression Models

Abstract

The determination of isotope ratios of lead finds many important applications in earth and planetary sciences. In this study, we report the first independent and fully calibrated absolute isotope ratio measurements of a common lead since the seminal work by the NIST in the 1960s, which has provided the widely used standards SRM 981 and SRM 982. This work employs MC-ICPMS for the absolute isotope ratio measurements, which were calibrated using two independent methods: the full gravimetric isotope mixture method based on the use of all four near-pure lead isotopes (the first application of this primary method to lead) and the regression method with NIST SRM 997 thallium isotopic standard as the primary calibrator. Both calibration methods provide results consistent to a few parts in 10 4 , which were used to characterize isotope ratios of lead in an NRC candidate reference material, high-purity common lead HIPB-1.

Solution to lead quantitation challenge

“…For the water sample, the lead isotopic composition was consistent with the average values reported by Millot and Négrel in French groundwater [3]. The two laboratories used primary standard solutions modeled after the isotopic composition of two international standards: the ERM-EB400 [4] and the HIPB-1 CRM [5]. As shown in Table 1, the lead isotopic composition for these materials is quite different and such discrepancies must be considered for data analysis.…”

Variation of lead isotopic composition and atomic weight in terrestrial materials (IUPAC Technical Report)

“…All publications identifying an isotopic reference material used as the reference for lead isotopic-abundance or isotope-ratio measurements used the elemental common lead NIST SRM 981 [14,29]. Other lead isotopic reference materials [33] include NIST SRM 610 lead in glass [34] and NRC HIPB-1 common lead [32]. Analytical uncertainty has improved substantially over the five-decade interval during which publications were generated; nevertheless, uncertainties of atomic-weight values are variable among publications.…”

“…Variation in atomic weight (solid black lines) of lead, A r (Pb), with amount fraction (solid orange lines) of 204 Pb, x( 204 Pb), of selected lead-bearing materials (data from Tables 1 and 2 and supplementary data file).Because lead has four isotopes whose variations are not mass dependent, the A r (Pb) and x( 204 Pb) values of the 25 materials shown in this figure coincide exactly only at the lower bound of A r (Pb), which explains why the A r (Pb) and x( 204 Pb) values of the common lead standard reference material 981 (solid circles labelled "SRM 981") and NRC HIPB-1[32] are not superimposed.…”

“…The A r (Pb) and x( 204 Pb) values in Fig. 1 are scaled so that they coincide exactly only at the lower and upper bounds of A r (Pb) and x( 204 Pb), which explains why the A r (Pb) and x( 204 Pb) values of the common lead SRM 981 [14,29] (solid circles labeled "SRM 981") and the reference material NRC HIPB-1 [32] are not superimposed. The axes on Figs.…”

Recent Advances in Nanocomposite Luminescent Metal-Organic Framework Sensors for Detecting Metal Ions

“…and tissues, such as the kidney, liver, brain, and bone, leading to calcium metabolism disorders, renal dysfunction, and increased risk of certain types of cancers. [85][86][87][88][89][90][91][92] Still, such metal ions are widely used in our daily life, since they are major components in many industries. Lead is used in batteries, gasoline, and pigments.…”