Iyini ikhebula elivumela imvelo futhi yiziphi izici zayo?Izintambo ezivumelana nemvelo zibhekisela ezintanjeni ezingenazo izinsimbi ezisindayo ezifana nomthofu, i-cadmium, i-chromium ene-hexavalent, i-mercury, njll., aziqukethe izinto ezibuyisela amalangabi e-brominated, azikhiqizi amagesi e-halogen ayingozi,...
Funda kabanzi