An Investigation of the Wild Rat Crown Incisor as an Indicator of Lead (Pb) Exposure Using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and Laser Ablation ICP-MS

• Published in: International Journal of Environmental Research and Public Health
• Main Authors: Kataba, Andrew, Nakayama, Shouta M. M., Nakata, Hokuto, Toyomaki, Haruya, Yohannes, Yared B., Yabe, John, Muzandu, Kaampwe, Zyambo, Golden, Kubota, Ayano, Matsukawa, Takehisa, Yokoyama, Kazuhito, Ikenaka, Yoshinori, Ishizuka, Mayumi
• Format: Text
• Language: English
• Published: MDPI 2021
• Subjects: Article; Rattus rattus
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830958/; http://www.ncbi.nlm.nih.gov/pubmed/33477475; https://doi.org/10.3390/ijerph18020767

Lead (Pb) is a metal toxicant of great public health concern. The present study investigated the applicability of the rat incisor in Pb exposure screening. The levels of lead in teeth (Pb-T) in the crown and root of incisors in laboratory Pb-exposed Sprague Dawley rats were quantified using inductively coupled plasma mass spectrometry (ICP-MS). The crown accumulated much Pb-T than the root of the Sprague Dawley rat incisor. The levels of lead in blood (Pb-B) were positively correlated with the Pb-T in the crown and root incisors of the Sprague Dawley rats. As an application of the Pb-T crown results in experimental rats, we subsequently analyzed the Pb-T in the crown incisors of Pb-exposed wild rats (Rattus rattus) sampled from residential sites within varying distances from an abandoned lead–zinc mine. The Pb-T accumulation in the crown of incisors of R. rattus rats decreased with increased distance away from the Pb–Zn mine. Furthermore, the Pb-T was strongly correlated (r = 0.85) with the Pb levels in the blood. Laser ablation ICP-MS Pb-T mappings revealed a homogenous distribution of Pb in the incisor with an increased intensity of Pb-T localized in the tip of the incisor crown bearing an enamel surface in both Sprague Dawley and R. rattus rats. These findings suggest that Pb-T in the crown incisor may be reflective of the rat’s environmental habitat, thus a possible indicator of Pb exposure.