Development of a voltammetric analytical method for the quantification of mercury in urine

Exposure to mercury represents a critical challenge for public health, necessitating precise and portable analytical methods for biomonitoring. This experimental analytical study develops an analytical method and evaluates the performance of square wave anodic stripping voltammetry (SWASV) for the quantification of mercury in urine. For this purpose, the operating conditions of the SWASV system were optimized through tests with standard mercury solutions. Commercial urine (BIO-RAD®) pretreated with nitric acid was used. Linearity, precision, trueness, limit of detection (LOD), and limit of quantification (LOQ) were evaluated. The results showed high precision, with a relative standard deviation (%RSD) of 6.21. Furthermore, the trueness analysis revealed no significant differences between SWASV and the cold vapor atomic absorption (CVAA) method, p = 0.2601. The LOD and LOQ were 0.68 and 2.2 μg L-1, respectively. These findings suggest that SWASV is a precise method comparable to CVAA for the detection of mercury in urine under controlled laboratory conditions. Additional studies are required to evaluate its applicability in real population biomonitoring scenarios.