High time resolution PM 10 chemical composition of urban city influenced by industry and North-African dust outbreaks in SW Europe

In this work, we present the results of high time resolution PM₁₀ chemical composition using online XRF spectrometer (Xact 625i) in the city of Huelva (SW of Spain) in September 2021-september 2022. The sampling was performed at the Campus monitoring station, which is belonging to Air Quality Network of the junta de Andalucía in the western part of the city of Huelva. Since 1970, Population is submitted to the hourly impact of industrial plumes related to Cu-metallurgy, phosphate production and petrochemical complex.

A total of 30 elements were analyzed in an hourly resolution. Moreover, other on-line pollutants were analyzed (N, BC, SO₂, NO₂, O₃ and PM₁₀). To compare the results obtained by Xact 625i to conventional chemical procedures using ICP-MS, ICPOES, IC and TOT, daily chemical composition of PM10 was characterized every 4 days during one year of sampling.

The results have shown how the impact of the industry occurs in the city of Huelva around 20% of the days every year. Days with poor air quality are influenced by the simultaneous impact of industry and North African air masses.

Nucleation of PM is synchronous with elements related to industrial activity (SO₂, As, Cu, Bi, Se, Pb, Ni, Zn and P). Another source of nucleation is traffic (BC, NO₂, Sn and Sb ). The highest concentrations of mineral dust are related to north African outbreak air masses Two elements (Si +Al) may contribute more than the daily limit value for this pollutant (50 µg m^-3).