Leadcare II Comparison with Graphite Furnace AtomicAbsorption Spectrophotometry for Blood Lead Measurementin Peruvian Highlands

Abstract

Peru is one of the countries with the highest leadcontamination in the world. Biological monitoring has lim-itations due to the shortage of laboratories with validatedmethodologies for the measurement of blood lead, and it isnecessary to use alternative methods for its measurement inhigh-altitude cities. We aimed to compare the blood leadlevels (BLL) measured by the LeadCare II (LC) method andGraphite Furnace Atomic Absorption Spectrometry (GF-AAS). We measured the BLL of 108 children from the city ofLa Oroya. The mean and median BLL for GF-AAS were10.77±4.18 and 10.44lg/dL, respectively; for the LCmethod, the mean was 11.71±4.28 and the median was11.60lg/dL. We found a positive linear correlation(Rho = 0.923) between both methods. Notwithstanding, theWilcoxon test suggests a significant difference between bothmethods (q= 0.000). In addition, the Bland–Altmananalysis indicates that there is a positive bias (0.94) in the LCmethod, and this method tends to overestimate the BLL.Likewise, we performed a generalized linear model toevaluate the influence of age and hemoglobin on BLL. Wefound that age and hemoglobin had a significant influence onBLL measured by the LC method. Finally, we used two non-parametric linear regression methods (Deming and Passing-Bablok regression) to compare the LC method with the GF-AAS. We found that these methods differ by at least a con-stant amount, and there would be a proportional differencebetween both. Although in general there is a positive linearcorrelation, the results of both methods differ significantly.Therefore, its use in cities located at high altitudes (higherthan 2440 m.a.s.l.) would not be recommended.