Karfe masu nauyi rukuni ne na abubuwan ganowa waɗanda suka haɗa da ƙarfe da ƙarfe kamar arsenic, cadmium, chromium, cobalt, jan ƙarfe, ƙarfe, gubar, manganese, mercury, nickel, tin da zinc. An san ions ƙarfe suna gurɓata ƙasa, yanayi da tsarin ruwa kuma suna da guba ...
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