Meltblown material formed from bicomponent polyolefin and polyester fibers

An article comprising:

• a nonwoven material, the nonwoven material comprising a plurality of bicomponent fibers each having a core and a sheath,
• wherein the core comprises from about 80 wt. % to about 98 wt. % of an olefin homopolymer, from about 3 wt. % to about 7 wt. % of a first charge enhancer package, and from about 2 wt. % to about 6 wt. % of a first antioxidant package, based on the total weight of the core,
• wherein the sheath comprises from about 80 wt. % to about 98 wt. % of a thermoplastic polyester, from about 2 wt. % to about 6 wt. % a second charge enhancer package, and from about 3 wt. % to about 9 wt. % of a second antioxidant package based on a total weight of the sheath, and
• wherein the nonwoven material exhibits a reduction in particle filtration efficiency after sterilization by gamma irradiation at a level of about 20 kilograys to about 30 kilograys of less than about 5%.