Iron(II) sulfate hydrate

Sprague-Dawley Rats (male, 5-6 weeks old)^[2]

35 mg Fe/kg diet (equivalent to 2.84 mg Fe/kg body weight/day); 70 mg Fe/kg diet (equivalent to 5.69 mg Fe/kg body weight/day); 140 mg Fe/kg diet (equivalent to 11.54 mg Fe/kg body weight/day)

oral dietary; daily; 31 or 61 days

Increased non‑heme iron levels in a dose‑dependent manner in the liver, spleen, and kidneys of rats at 31 and 61 days.
Elevated liver non‑heme iron to 67.2, 89.0, and 116.1 μg Fe/g tissue; spleen non‑heme iron to 171.0, 213.0, and 285.6 μg Fe/g tissue; kidney non‑heme iron to 29.0, 30.3, and 31.5 μg Fe/g tissue in low‑, mid‑, and high‑dose groups at 31 days, respectively.
Significantly increased mean corpuscular hemoglobin to 1.30 fmol in the high‑dose group compared with the low‑dose group at 31 days.
Increased liver non‑heme iron to 105.6, 120.2, and 126.4 μg Fe/g tissue; spleen non‑heme iron to 1018.5, 1107.2, and 1126.4 μg Fe/g tissue; kidney non‑heme iron to 43.5, 49.0, and 48.0 μg Fe/g tissue in low‑, mid‑, and high‑dose groups at 61 days, respectively.
Significantly elevated total iron binding capacity to 99.6 mmol/l in the low‑dose group relative to mid‑ and high‑dose groups at 61 days.
Maintained plasma iron concentrations within normal ranges and never exceeded 28.8 μmol/l at any dose or duration.