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In recent years, the conceptual advancement on green analytical chemistry (GAC) has moved in parallel with efforts to incorporate new screening or quantitative low-cost analytical tools to solve analytical problems. In this sense, the role of solid state techniques that allow the non-invasive analysis (or with a minimum sample treatment) of solid samples cannot be neglected. This review describes the basic principles, instrumentation and advances in the application of X-ray fluorescence instrumentation to the environmental sciences research topics, published between 2006 and 2020. Obviously, and because of the enormous number of works that can be found in the literature, it is not possible to exhaustively cover all published articles and the diversity of topics related to the environment in which a solid state technique like XRF has been applied successfully. It is a question of making a compilation of the instrumentation in use, the significant advances in XRF spectrometry and sample treatment strategies to highlight the potential of its implementation for environmental assessment.

Air pollution is harming our health and that of our children and parents. Air pollution causes many harmful effects, ranging from premature death, to headaches, coughing and asthma attacks. Previous studies (2008-2009) of particulate matter at Wainuiomata, Lower Hutt showed that biomass burning was primarily responsible for peak PM₂.₅ and PM₁₀ concentrations and exceedances of the National Environmental Standard (NES) and the New Zealand Ambient Air Quality Guidelines (NZAAQG). Arsenic was also found to be associated with biomass burning sources during winter at Wainuiomata. The source of arsenic was considered to be due to the use of copper chromium arsenate (CCA) treated timber as solid fuel for fires for domestic heating. While particulate matter pollution from domestic fires itself presents a health risk for the exposed population, the addition of arsenic to the mix enhances the potential risk. The use of CCA treated timber was unlikely to be used on a regular basis hence the peak arsenic concentrations did not always coincide with peak contributions from domestic fires and that the use of CCA – treated timber is more intermittent and opportunistic. This work compared several different analytical methodologies for the determination of arsenic in air particulate matter. The primary purpose was to use a standard analytical method as recommended by the NZAAQ guidelines and compare those results with the Ion Beam Analysis (IBA) and X-ray Fluorescence Spectroscopy (XRF) methods used to determine arsenic concentrations in previous studies. Through this collaborative research with GNS Science and GWRC, it was found that annual PM₁₀ and PM₂.₅ averages were well within the NZAAQG values of; 20 μg m⁻³ and 10 μg m⁻³ respectively. There was a much correlated seasonal and temporal variations observed for black carbon (BC), PM₂.₅ and arsenic concentrations. The overall concentrations of BC, PM₂.₅ and PM₁₀ have decreased significantly in the Wainuiomata airshed compared to pre

Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNA damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs., AuthorCount:6

Air pollution with particulate matter (PM) raises considerable concern because of its adverse effects on human health. For this reason, and because the mechanisms of PM toxicity are not fully known, there is an urgent need to determine the chemical constituents of atmospheric PM, especially PM emanating from traffic - a major source of urban PM. This thesis describes analytical methods that have been developed for determining polycyclic aromatic hydrocarbons (PAHs) in ambient air and vehicle exhaust PM, focusing particularly on benzo(a)pyrene (B(a)P) and the dibenzopyrenes: dibenzo(a,l)pyrene, dibenzo(a,e)pyrene, dibenzo(a,i)pyrene and dibenzo(a,h)pyrene. Trace amounts in complex matrices have been met by coupling parts or the entire clean-up step using liquid chromatography on-line with the analysis step using gas chromatography-mass spectrometry into one automated system. Application of the methodology, using either ultrasonic assisted extraction (USE) or accelerated solvent extraction (ASE), to a National Institute of Standards and Technology (NIST) urban air standard reference material (SRM) yielded comparable or higher concentrations than the assigned NIST values, validating the approach. However, ASE provided higher extraction yields from diesel particulate SRMs than USE, and ASE of diesel SRMs generally yielded higher concentrations than the corresponding NIST values. Concentrations of dibenzopyrenes in Stockholm air PM, and gasoline- and diesel-fuelled vehicle emissions (ng/km), are reported for the first time. When adjusted in terms of their relative carcinogenic potencies, the dibenzopyrenes were found to pose greater carcinogenic hazards than B(a)P, indicating that the current use of B(a)P as a marker probably leads to underestimates of the carcinogenicity of PAHs in ambient air. The developed methods also worked well for analyzing larger molecular weight PAHs: more than 60 and 170 potential PAHs were detected in ambient air PM and diesel PM, respectively

Air particulate matter (PM) and bound chemicals are potential mediators for adverse health effects. The cytotoxicity and changes in energy-providing processes caused by chemical compounds bound to PM of different size fractions were investigated in Tetrahymena pyriformis. The PM samplings were carried out using a high volume cascade impactor (6 size fractions between 10 m and less than 0.49 m) at three points of La Plata, Argentina: in an industrial area, a traffic-influenced urban area, and a control area. Extracts from respirable particles below 1 m initiated the highest cytotoxic effects, demonstrating their higher risk. In contrast, an increase on oxygen consumption was observed especially in tests of extracts from particles less than 1 m from urban and industrial areas. The increase on oxygen consumption could be caused by decoupling processes in the respiratory chain. Otherwise the ATP concentration was increased too, even though to a lower extent. The observed imbalance between oxygen consumption and ATP concentration in exposed T. pyriformis cells may be due to oxidative stress, caused by chemical compounds bound to the particles. Owing to the complexity of effects related to PM and their associated chemical compounds, various physiological parameters necessarily need to be investigated to obtain more information about their possible involvement in human relevant pathogenic processes. As shown here, effects on cell proliferation and on energy-providing processes are suitable indicators for the different impact of PM and adsorbed chemicals from various sampling locations. © 2006 Wiley Periodicals, Inc. Environ Toxicol 21: 457-463, 2006.