title: Season as a factor in variability of blood-lead levels in children.
mesh_terms: D002136:Calcium, Dietary / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007854:Lead / Q000097:blood*; D007855:Lead Poisoning / Q000517:prevention & control; D012621:Seasons; D014807:Vitamin D / Q000008:administration & dosage / Q000097:blood
chemical_list: D002136:Calcium, Dietary; D014807:Vitamin D; D007854:Lead