Te whanaketanga o te ao whānuiumanga kakahuKua piki ake te kai kakahu ia tangata i ia tau mai i te 7kg ki te 13kg, me te nui katoa neke atu i te 100 miriona tana, ā, kua eke te hanga kakahu para i ia tau ki te 40 miriona tana. I te tau 2020, ka hangarua e tōku whenua nui te 4.3 miriona tana o ngā kakahu, ā, ka neke atu i te 60 miriona tana te putanga o ngā muka matū. Ahakoa he nui te maha o ngā kaweake kakahu, he iti te tere hangarua. Neke atu i te 2/3 o ngā kakahu para o te ao kāore anō kia taea te whakapai ake me te hangarua.

Ko ngā mea e kiia nei he papanga whakahou ake e kiia whānuitia ana he mea hangarua.ngā kakahuka taea te whakamahi anō, ā, he rite tonu te mahi a ngā hua kua hangaia anō, ā, he nui ake te uarangā papanga takitahiMō ngā hua kakahu "parakore" pirau-kore, kāore nei he uara ōhanga hei whakaora tonu, ka taea te waiho hei whakawairakau ki te whenua ururua. Haunga tēnei ariā o te ōhanga porowhita, ka wehea e te hangarau ahumahi te hangarua kia rua ngā momo: te whakapai ake me te whakaheke iho.

Ko ngā tikanga hangarua kakahu ko ngā tikanga ā-ringa, ā-tinana, me te matū. Ko te tikanga ā-ringa he tukatuka i ngā kakahu kia angiangi, kia mirohia rānei, kia hurihia rānei te kaupapa matua o ngā kakahu; ko te tikanga ā-tinana he mea hanga mō ngā muka hangai, inā koa ko ngā muka i hangaia mā te miro rewa, ka rewahia i te pāmahana teitei kia rewa ai ngā kakahu. I muri i te tātari i ngā poke, ka taea te miro, te whakamahi rānei i roto i ētahi atu hua. Ka taea e ētahi rauemi muka hiato mahi teitei te tango i te kapia epoxy i te pāmahana teitei, te whakahoki i te āhua muka, ā, ka whakamahia ki roto i ngā hua kore-kahu mā te tapahi me te kuru; ko ngā tikanga matū he mea hanga mō ngā momo kakahu. Ka hangarua motuhaketia te wehenga o ngā muka, ā, he maha ngā wā e whakamahia ana hei pure i ngā rauemi hangarua, hei tango pai ake i ngā poke me ngā tae, me te whakatinana i te whakapai ake me te whakaora.

I te tau 2020, ko te putanga muka polyester o tōku whenua he 49.3575 miriona tana, e 72% o te katoa, ko te miro he 8.6 miriona tana, e 12%, ko te viscose he 3.95 miriona tana, e 5.8%, ko te nairona he 5.6%. Ko ngā muka e toe ana he iti iho i te 4%. Hei whakarite i te whakarato kai, kei te heke haere te putanga o ngā muka taiao pēnei i te miro, te rinena, me te huruhuru hipi. He rautaki ā-wāhanga te whakakapi i ētahi muka taiao ki ngā muka hangai. Ka taea e te pūtake o ngā rauemi mata muka hangai te whiriwhiri i ngā rauemi koiora, ā, me whakamahi ngā rauemi whakahou hangarua hei whakakore mārire i te whakawhirinaki nui ki ngā rauemi kāore e taea te whakahou. Ehara i te mea he mea whai hua noa iho tēnei mō te whakaora rauemi, te tiaki i te taiao me te whakaiti i te noho o te whenua ahuwhenua, engari he mea nui hoki mō te hanganga me te whanaketanga o te ōhanga porowhita.