Table 6 Grouping of elements in PM ₁₀ according to the ratio of summer to winter seasonal average

Outskirt

Al, Ba, Ca, Ce, Cs, Eu, Fe, Hf, K, La, Mg, Na, Rb, Sc, Ta, Tb, Th, Ti, U, Zr

Ag, As, Br, Cl, Co, Hg, I, Mn, Sb, Se, Tl

Cd, Cr, Mo, Ni, Pb, V, Zn

Downtown

Al, Br, K, Na, Ti, U

Ag, Ca, Cd, Ce, Co, Eu, Fe, Hf, La, Mg, Mn, Mo, Ni, Se, Tb, Th, Zr

As, Ba, Cl, Cr, Cs, I, Pb, Rb, Sb, Sc, Ta, Tl, V, Zn