Here you go:
IOWA
Iowa prohibits any shot shells containing shot of any size other than number 2 or 3 nontoxic shot or number 4, 5, 6, 7 ½, or 8 lead or nontoxic shot on person while hunting wild turkey. (See IOWA ADMIN. CODE 571-98.2(483A); IOWA ADMIN. CODE 571-99.8 (481A)).
Iowa prohibits any target shooters using shotguns with lead shot that discharges over water. (See IOWA ADMIN. CODE 571-51.3(481A)).
The Iowa Department of Natural Resources offers education programs on alternatives to lead ammunition.
THE FOLLOWING IOWA WILDLIFE MANAGEMENT AREAS REQUIRE NONTOXIC SHOT FOR ALL HUNTING [EXCLUDING DEER AND WILD TURKEY]:
Benton County, Iowa River Corridor; Boone County, Harrier Marsh WMA; Buena Vista County, all state and federal areas; Calhoun County, South Twin Lake, Cerro Gordo County, all state and federal areas; Clay County, all state and federal areas except the Ocheyedan WMA target shooting range; Dickinson County, all state and federal areas except the Spring Run WMA target shooting area; Emmet County, all state and federal areas; Franklin County, all state and federal areas; Greene County, all state and federal areas except Rippey Access and McMahon Access; Guthrie County, McCord Pond, Lakin Slough and Bays Branch WMAs, excluding the target shooting range at Bays Branch WMA. Also, Hamilton County, Little Wall Lake, Gordon Marsh and Bauer Slough WMAs; Hancock County, all state and federal areas; Humboldt County, all state and federal areas; Iowa County, Iowa River Corridor, Jasper County, Chichaqua Wildlife Management Area; Kossuth County, all state and federal areas; Osceola County, all state and federal areas; Palo Alto County, all state and federal areas; Pocahontas County; all state and federal areas except Kalsow Prairie; Polk County, Paul Errington Marsh WMA and Chichaqua WMAs; Sac County, all state and federal areas except White Horse
Access and Sac City Access; Story County, Colo Bog and Hendrickson Marsh; Tama County, Iowa River Corridor; Winnebago County, all state and federal areas; Worth County, all state and federal areas; and Wright County, all state and federal areas. Target shooting on these areas will also require the use of nontoxic shot.