Suitability of anodic stripping voltammetry for routine analysis of venous blood from raptors

Abstract

Lead (Pb) poisoning is a significant threat faced by raptors. Hence, rapid Pb diagnosis has become a priority during the admission of raptors in wildlife recovery centers, and bench-top analyzers, such as LeadCare II ®, are routinely employed for this purpose. However, this device has been designed for conducting analyses of human blood Pb levels (BLLs), and the validity of this methodology for whole blood from raptors has, to date, rarely been assessed. In addition, a recent recall by the US Food and Drug Administration has recommended discontinuing the use of this analyzer for human venous blood because it may underestimate the BLL. We evaluated the precision of BLL measurements taken with LeadCare II by comparing them with those obtained with inductively coupled plasma mass spectrometry (ICP-MS). Our sample contained venous blood from 105 raptors belonging to 4 species. The results showed a good correlation between the 2 techniques (Spearman's r = 0.927, p < 0.0001). The mean BLL with ICP-MS was 19.6 μg/dL; it was found to be 18.7 μg/dL with LeadCare II. A Bland-Altman analysis indicated that the bias between the mean differences was only 0.5 μg/dL, but it had a high standard deviation of bias (5.7 μg/dL) and 95% limits of agreement from –10.75 to 11.74 μg/dL. The present results indicated that LeadCare II has an overall sensitivity of 71.8% and a positive predictive value of 76.3%. The specificity of LeadCare II for detecting animals with low BLL (<3.4 μg/dL) was 96.4%, and the negative predictive value (the probability that a value below the limit of detection of LeadCare II has a true correspondence with the actual value) was 100%. The present results indicated that, although LeadCare II might be imperfect in the estimation of BLLs in raptors, it performs reasonably well and might be employed in the clinical setting to assess patients potentially suffering from Pb poisoning. Environ Toxicol Chem 2019;9999:1–11. © 2018 SETAC.