Table 1.

Industrial branches – emitters of heavy metals.

Industrial branch	Cd	Cr	Cu	Hg	Pb	Ni	Sn	Zn
Paper industry	-	+	+	+	+	+	-	-
Petrochemistry	+	+	-	+	+	-	+	+
Production of clorine	+	+	-	+	+	-	+	+
Fertilizer industry	+	+	+	+	+	+	-	+
Ironworks and steelworks	+	+	+	+	+	+	+	+