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This content will become publicly available on March 1, 2026

Title: The forgotten element: Why do we ignore calcium in otolith studies?
Typical analyses of otolith microchemistry use calcium, a major constituent, as an internal standard, setting its value as a constant and ignoring any potential variations. In fact, patterns do occur in otolith Ca deposition, as can be observed either by repeating the analysis, by creating two-dimensional maps of Ca, or both. Here we present evidence of Ca variations in fish otoliths from analyses using synchrotron-based scanning X-ray fluorescence microscopy, electron microprobe analysis, and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). 2-D maps of otoliths created with LA-ICP-MS indicate that Ca is elevated where especially Zn and P are low, and vice versa, suggesting that spatial variations in protein deposition may affect concentrations of Ca. We encourage others to examine Ca concentrations in their biomineralized samples to check for variations, using LA-ICP-MS and other methods.  more » « less
Award ID(s):
1923965
PAR ID:
10576084
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Fisheries Research
Volume:
283
Issue:
C
ISSN:
0165-7836
Page Range / eLocation ID:
107297
Subject(s) / Keyword(s):
Calcium Internal standard 2-D elemental mapping Multiple analytical approaches
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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