Atomic spectrometry update – a review of advances in environmental analysis

Abstract

Highlights in the field of air analysis included: a new focus on measuring micro- and nanoplastic particles in air, the development of hyphenated ICP-MS systems for in situ sampling and measurement of airborne metallic particles and the reported use of wearable black carbon sensors for measuring exposure to diesel fumes within the workplace. Significant advancements in the analysis of waters have been made in developing novel resin materials and new protocols for existing commercially available resins, aimed at the determination and speciation of trace levels of metals and metalloids in water matrices. These developments have been validated for sample purification and pre-concentration. In addition to traditional column chemistry, on-line hyphenated techniques were employed to enhance speciation analysis, with optimized methods enabling faster analysis and facilitating a more holistic approach by allowing the simultaneous detection of multiple species or elements in a single run. Efforts have also been directed towards detecting particles in the micro- and nanometer range, broadening the analytical scope beyond the ionic fraction. This year, the focus shifted from natural and engineered nanoparticles towards the critical field of plastic pollution, with several innovative methodologies introduced. Furthermore, to achieve better precision and lower detection limits in the field of MS/MS, numerous studies explored the behaviour of gases and reactions within reaction cells, contributing to the refinement of these techniques. In the analysis of soils and plants, methods aimed at improving the efficiency of green solvents were again prominent. Developments in AES were largely driven by the desire to create small, low-cost, low-power-consumption instrumentation suitable for field deployment. The study of NPs in soil and plant systems continued to be a focus for sp-ICP-MS. The past year has again seen a large volume of publications featuring LIBS, with particular interest in methods to enhance signal intensity and thereby improve limits of detection. Of interest in XRF was the development of in-house spectrometers for underwater mercury screening and in vivo plant analysis. Developments in geological analysis include new homogeneous natural and synthetic materials that have been developed as reference materials (RMs) in the analysis of geological samples by microanalytical techniques, such as LA-ICP-MS, LIBS and SIMS. Additional information on already existing RMs has been obtained for in situ isotope ratio determinations. Attention has been paid to sample preparation and purification methods able to shorten the analysis time and to improve the accuracy. Much attention has been paid to the use of LA-ICP-MS/MS as a means for removing spectral interferences in the case of in situ localized isotopic analysis and dating of geological materials. The development of new chemometric models as well as software has continued to improve data quality. The use of artificial intelligence is growing and techniques such as machine learning have led to significant improvements in the quality of geochemical results.