Ekitereeza .
Stabilizers ze "intetionally added additives" ezikozesebwa okukuuma polymers okuva ku butonde obukosa (ebbugumu, UV ekitangaala, n'ebirala). Ziteekebwa mu buveera okukuuma polimeeri okuva ku bbugumu (thermal), UV n’okuvunda kw’ebyuma nga bikolebwa n’okubikozesa. Zikola nga ebirungo ebiziyiza obuwuka obuleeta obulwadde, ebinyweza ebbugumu (ebbugumu) n’ekitangaala/ekitangaala (UV), ebiziyiza ennimi z’omuliro/ebiziyiza omuliro n’ebiwoomerera oxygen. Ku PVC, ebbugumu ly’okuvunda kw’ebbugumu liri kumpi n’ebbugumu ly’enkola, kale okukozesa ebitereeza ebbugumu ebituufu mu kiseera ky’okugirongoosa kyetaagisa nnyo.
Ebimu ku binyweza biyinza okubaamu ebyuma ebimu ebizito oba ayoni zaabyo (okugeza ebitebenkedde ku bifaananyi by’amadirisa ga PVC era payipu zisinga kuba lead-okusinziira oba barium, cadmium oba zinc compounds, nga kwogasse organo-ebirungo bya nickel bikozesebwa nnyo okutebenkeza UV), ekiyinza okuleeta obulabe eri obulamu.
Ebikulu ebinyweza ebbugumu ebiriwo ku PVC bye bino:
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Ebirungo ebikulembera (okusinga ekirungo kya lead sulfate ne lead stearate). Ebika byonna eby’omusulo biba bya butwa nnyo eri abantu olw’engeri gye bikuŋŋaanyizibwamu. Okunoonyereza kulaga nti omusulo guyinza okuleeta okwonooneka kw’obwongo, obulemu ku kuyiga, puleesa n’okuggwaamu embuto. Okukwatibwa omusulo-okusingira ddala amazzi agafuuse amakyafu kizibu ekibunye ennyo mu bulabe obw’amaanyi eri obulamu. Bwe kiyingizibwa mu nkola y’omu lubuto, omusulo guyinza okukuŋŋaanyizibwa mu bitundu by’omubiri n’amagumba, okukkakkana nga kivuddeko endwadde ez’enjawulo okuva ku kukendeera kw’omusaayi okutuuka ku kukendeera kw’obusimu (Godwin, 2001). WHO etegeeza lead level ya 10 ug/L mu mazzi ag’okunywa (WHO, 2006).
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Ebirungo bya organotin okusinga birimu monobutyltin (MBT), dibutyltin (DBT) ne tributyltin (TBT). Okugatta ku ekyo, dimethyltin (DMT), organotin endala ezuuliddwa mu mazzi g’awaka, eva ku bitereeza ebikozesebwa mu PVC ne chlorinated PVC (CPVC) products (Ehman et al., 2007). Kibadde kiteeberezebwa nti ebirungo bya organotin biyinza okuba nga binywevu era nga bya butwa eri obusimu obw’omu makkati n’abaserikale b’omubiri, awamu n’ekibumba (Korgiesen ne Rice, 1998). Ebirungo ebikola ekirungo kya organotin bikola ebitundu nga 9.3% ku bikozesebwa mu kutebenkeza omubiri mu Bulaaya (CEC, 2000).
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Cadmium (CD) n’enkola zaayo ez’omunnyo enzibu. CD butwa obukuŋŋaanyiziddwa mu lukalala lw’ebintu 10 ebisinga okubeera eby’obulabe mu nteekateeka y’ekibiina ky’amawanga amagatte ey’obutonde bw’ensi; Kiyinza okuleeta okwonooneka kw’ekibumba n’okukendeeza omusaayi, era bw’omala okunnyika, kiyinza okusigala mu mubiri gw’omuntu okumala emyaka 30. Okussa omukka gwa cadmium oxide kye kisinga obulabe, nga kirimu ebivaamu bingi ebitta.
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Antimony (SB) ekozesebwa mu PVC okutumbula ekikolwa ky’okuziyiza ennimi z’omuliro ekya chlorine.
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Organochlorines zitera okwetaagibwa okutumbula okuddamu kw’ennimi z’omuliro n’amaanyi g’amaanyi g’okukuba kwa PVC.
