▁harm ful ▁em issions . ▁ ▁A ▁study ▁performed ▁by ▁the ▁Ch on bu k ▁National ▁University ▁concluded ▁that ▁a ▁B 3 0 ▁b iod ies el ▁bl end ▁reduced ▁carbon ▁mon ox ide ▁em issions ▁by ▁approximately ▁ 8 3 % ▁and ▁partic ulate ▁matter ▁em issions ▁by ▁roughly ▁ 3 3 %. ▁ ▁NO x ▁em issions , ▁however , ▁were ▁found ▁to ▁increase ▁without ▁the ▁application ▁of ▁an ▁E . G . R . ▁system . ▁ ▁The ▁study ▁also ▁concluded ▁that , ▁with ▁E . G . R , ▁a ▁B 2 0 ▁b iod ies el ▁bl end ▁consider ably ▁reduced ▁the ▁em issions ▁of ▁the ▁engine . ▁ ▁Additionally , ▁analysis ▁by ▁the ▁California ▁Air ▁Resources ▁Board ▁found ▁that ▁b iod ies el ▁had ▁the ▁lowest ▁carbon ▁em issions ▁of ▁the ▁fu els ▁tested , ▁those ▁being ▁ult ra - low - s ulf ur ▁dies el , ▁gas oline , ▁corn - based ▁eth an ol , ▁com pressed ▁natural ▁gas , ▁and ▁five ▁types ▁of ▁b iod ies el ▁from ▁varying ▁feed stock s . ▁ ▁Their ▁conclus ions ▁also ▁showed ▁great ▁variance ▁in ▁carbon ▁em issions ▁of ▁b iod ies el ▁based ▁on ▁the ▁feed stock ▁used . ▁ ▁Of ▁so y , ▁t allow , ▁can ola , ▁corn , ▁and ▁used ▁cook ing ▁oil , ▁so y ▁showed ▁the ▁highest ▁carbon ▁em issions , ▁while ▁used ▁cook ing ▁oil ▁produced ▁the ▁lowest . ▁ ▁While ▁studying ▁the ▁effect ▁of ▁b iod ies