Zvigadzirwa zvedu zvakapfuura zvakajairwa bvunzo kuti uve nechokwadi chehunhu uye chakasimbiswa nemasangano ane masimba kumba uye kunze kwenyika. Isu takawana chitupa kubva kuUS ul, iyo European Union Rohs, iyo National Ruzivo Indasitiri Park uye Ningbo Institute yeMhando Yekutarisa uye Kutsvaga. Iyo core index yekabati iri pamusoro wepamusoro-soro muindasitiri.
