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In this paper, atmospheric water-soluble cation and anion contents of PM₁₀ are analysed in Makkah, Saudi Arabia. PM₁₀ samples were collected at five sites for a whole year. PM₁₀ concentrations (µg/m³) ranged from 82.11 to 739.61 at Aziziyah, 65.37 to 421.71 at Sanaiyah, 25.20 to 466.60 at Misfalah, 52.56 to 507.23 at Abdeyah, and 40.91 to 471.99 at Askan. Both daily and annual averaged PM₁₀ concentrations exceeded WHO and Saudi Arabia national air quality limits. Daily averaged PM₁₀ concentration exceeded the national air quality limits of 340 µg/m³, 32% of the time at Aziziyah, 8% of the time at Sanaiyah, and 6% of the time at the other three sites. On average, the cations and anions made a 37.81% contribution to the PM₁₀ concentrations. SO₄²⁻, NO₃⁻, Ca²⁺, Na⁺, and Cl⁻ contributed 50.25%, 16.43%, 12.11%, 11.12%, and 8.70% to the total ion concentrations, respectively. The minor ions (F⁻, Br⁻, Mg²⁺, NO₂⁻, and PO₄³⁻) contributed just over 1% to the ion mass. Four principal components explained 89% variations in PM₁₀ concentrations. Four major emission sources were identified: (a) Road traffic, including emission from the exhaust, wear-and-tear, and the resuspension of dust particles (F⁻, SO₄²⁻, NO₃⁻, Ca²⁺, Na⁺, Mg⁺, Br⁻, Cl⁻, NO₂⁻, PO₄³⁻); (b) Mineral dust (Cl⁻, F⁻, Na⁺, Ca²⁺, Mg²⁺, PO₄³⁻); (c) Industries and construction–demolition work (F⁻, SO₄²⁻, Ca²⁺, Mg²⁺); and (d) Seaspray and marine aerosols (Cl⁻, Br⁻, Mg²⁺, Na⁺). Future work would include an analysis of the metal contents of PM₁₀ and their spatiotemporal variability in Makkah.