Application of a near real-time technique for the assessment of atmospheric arsenic and metals emissions from a copper smelter in an urban area of SW Europe

Emissions of metals and metalloids as a result of industrial processes, entail a great risk to human health. A high time resolution study on arsenic levels in PM₁₀ in the city of Huelva (SW Spain) was carried out between September 2021 and September 2022. Hourly data obtained with a near real-time technique based on X-ray fluorescence were inter-compared with other offline analytical instrumentation. The results showed that the main origin of As and other metal(loid)s such as Zn and Pb, was the copper smelter located southwest to the city. Although the mean concentration of As during the study period (2.8 ng m^-3) was lower than the target value (6 ng m^-3) proposed by the European Directive 2004/107/EC, hourly peaks of up to 311 ng m^-3 were measured. The highest concentrations of arsenic were reached in the early afternoon, related to the influence of breeze. A source apportionment study has identified five major sources of PM₁₀: mineral, marine, combustion, regional and industry. The industrial source is characterized by high concentrations of As, Cu, Pb and Zn, contributing 1% of the total concentration of PM₁₀ and related to copper smelter emissions. In addition, the analysis of two extreme North African dust outbreak events that affected southwestern Europe in March 2022, showed that this natural source contributed slightly to arsenic levels. The need to carry out high time resolution studies is demonstrated to better understand the variability in exposure to industrial metal(loid)s by the population, compared to conventional 24-h studies.