Monitoring Lead (Pb) Pollution and Identifying Pb Pollution Sources in Japan Using Stable Pb Isotope Analysis with Kidneys of Wild Rats

Abstract

Although Japan has been considered to have little lead (Pb) pollution in modern times, the actual pollution situation is unclear. The present study aims to investigate the extent of Pb pollution and to identify the pollution sources in Japan using stable Pb isotope analysis with kidneys of wild rats. Wild brown (Rattus norvegicus, n = 43) and black (R. rattus, n = 98) rats were trapped from various sites in Japan. Mean Pb concentrations in the kidneys of rats from Okinawa (15.58 mg/kg, dry weight), Aichi (10.83), Niigata (10.62), Fukuoka (8.09), Ibaraki (5.06), Kyoto (4.58), Osaka (4.57), Kanagawa (3.42), and Tokyo (3.40) were above the threshold (2.50) for histological kidney changes. Similarly, compared with the previous report, it was regarded that even structural and functional kidney damage as well as neurotoxicity have spread among rats in Japan. Additionally, the possibility of human exposure to a high level of Pb was assumed. In regard to stable Pb isotope analysis, distinctive values of stable Pb isotope ratios (Pb-IRs) were detected in some kidney samples with Pb levels above 5.0 mg/kg. This result indicated that composite factors are involved in Pb pollution. However, the identification of a concrete pollution source has not been accomplished due to limited differences among previously reported values of Pb isotope composition in circulating Pb products. Namely, the current study established the limit of Pb isotope analysis for source identification. Further detailed research about monitoring Pb pollution in Japan and the demonstration of a novel method to identify Pb sources are needed.

Metal contamination and fractionation in sediments from the lower basin of the Vale do Ribeira (SE, Brazil)

“…Lead, the characteristic element mining discharges in RIR, has been recognized as tracer of the environmental status of the basin by many authors (Charalampides and Manoliadis 2002;Moraes et al 2004;Abessa et al 2014;Nakata et al 2017). The mobility of Pb close to the abandoned mines corresponds to the release kinetics data fitting to parabolic equations of diffusion, greater associated with the first phase (Buschle et al 2010).…”

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

“…The Pb concentration in the blood and incisors teeth collected from the laboratory exposed Sprague Dawley rats and the R. rattus rats from Kabwe, Zambia were quantified. In the current study, blood and teeth were digested using the microwave acid method previously described by Nakata et al [ 27 , 28 ] with minor modifications. To minimize surface contamination and remove excess blood, the teeth were firstly cleaned using an ultrasonic bath method as described by Ishii et al [ 29 ] with some modifications.…”

“…The Pb concentration quantification was performed using the ICP-MS (7700 series; Agilent Technologies, Tokyo, Japan), as described by Nakata et al [ 28 , 29 ] with minor modifications. The operating conditions of ICP-MS were as given in the Supplementary Table S3 .…”

Relationship between blood test values and blood lead (Pb) levels in Black-headed gull (<i>Chroicocephalus ridibundus</i>: Laridae)

“…In Japan, the use of lead bullets has only been restricted in Hokkaido since 2000 [ 4 , 37 ]. Nakata et al [ 41 ] reported that environmental lead pollution had mainly occurred in southern areas of Japan by assessing lead accumulation levels in wild caught two Rattus species ( Rattus norvegicus and Rattus rattus ). In Japan, some wild birds are affected by lead pollution, such as gooses and swans [ 40 , 42 , 43 , 44 ].…”