1. HDG

☆ Uru ndị bụ isi bụ ezigbo ike ịgbado ọkụ na iguzogide kọntaktị kwesịrị ekwesị. N'ihi ezigbo ihe ndị na-eme ka mmanụ dị n'ahụ, a na-ejikarị ihe mkpuchi cadmium eme ihe n'ụgbọelu, ụgbọelu, mmiri, na ngwaahịa redio na eletrọnịkị. Ihe mkpuchi ahụ na-echebe ihe mkpuchi ígwè ahụ site na nchekwa igwe na kemịkalụ, yabụ iguzogide nchara ya ka mma karịa mkpuchi zinc. Zinc na-ekpo ọkụ nwere ezigbo ike iguzogide nchara, nchebe àjà maka ihe mkpuchi ígwè, ike iguzogide ihu igwe dị elu, na iguzogide mbuze mmiri nnu. Ọ dabara adaba maka osisi kemịkalụ, ụlọ ọrụ mmepụta ihe na ikpo okwu ọrụ n'ụsọ oké osimiri na n'ụsọ oké osimiri.