Characterization of the spatial and temporal distribution of lead around a battery industrial park by LA-SPAMS.

A convenient technique for direct solids analysis, laser ablation single particle aerosol mass spectrometry (LA-SPAMS), was used to investigate lead and other components in soil and bark samples from around a battery industrial park. In total, over 50,000 particles ranging in size from 0.2 to 2 μm were sampled and approximately 15-35% of the particles were analyzed for chemical composition. The mean mass spectrum results showed that the intensity of lead varied widely among sampling points, reaching the highest intensity in the topsoil and bark at sampling point 4, located closest to the core factory. Based on the neural network algorithm of adaptive resonance theory (ART-2a), the topsoil and bark samples were classified into five categories: crustal composition (Ca, silicates, aluminates, etc.), elemental carbon (C, C, C, etc.), organic carbon (CN, levoglucosan, etc.), secondary inorganic sources (phosphates, nitrates, sulfates), and heavy metals (Pb, Zn, Cu), with the proportion of Pb varying from 0.020 to 0.25% and 0.030-9.41% in topsoil and bark samples, respectively, while the proportion of Cu and Zn in topsoil and bark samples did not differ as greatly as Pb. In addition, the particle number concentrations of lead particles in topsoil and bark ranged from 0.14 to 3.48% and 0.36-37.93%, respectively. The concentrations of Pb in topsoil and bark samples measured by ICP-OES varied from 71 to 791 ppm and 172-2595 ppm, respectively. Overall, both the lead content in topsoil samples measured by LA-SPAMS and ICP-OES reached maximum values at sampling points 4 and 5, respectively, indicating moderate pollution with Pb at these two sites. This convenient LA-SPAMS method not only accurately detects the composition of solid samples, the mixing state of particulate matter, and the analytical component sources, but also omits tedious pretreatment steps, reduces the use of organic solvents, and shortens the detection time of solid samples, thereby providing an attractive method for soil environmental quality monitoring.