Kutanga kutora chiyero, kunyorera vamiririri venyika, kutora chikamu mukuongororwa kwemubairo, nano sirivheri-yakavakirwa formaldehyde yekubvisa mvura yakahwina iyo yenyika yemukati yekushongedza mubatanidzwa zvakakosha zvekurudziro zvigadzirwa.