Heavy Metals, Iron, and Arsenic in Water and Sediment from a Cold Spring in Southwest Ohio

摘要

Concentrations of iron, lead, arsenic, manganese, zinc, and cadmium in the water and sediment of the Yellow Spring, an artesian spring in a Southwest Ohio nature preserve, were measured. Dissolved oxygen, specific conductance, pH, and sulfate were measured to determine if pyrite is the source of elevated iron in the water and sediment. Manganese exceeded the US EPA limit of 50 μg/L in the water and arsenic was just under the US EPA limit of 10 μg/L. Exposure to the Yellow Spring as a drinking water source could cause a slight risk for arsenic and manganese exposure. Use of the Yellow Spring as a drinking water source should be avoided. In the sediment, arsenic (57.91 ± 10.95 mg/kg dry weight) and cadmium (0.615 ± 0.068 mg/kg dry weight) were strongly associated with iron indicating that they originate from arsenopyrite minerals. Lead (8.211 ± 0.950 mg/kg dry weight) and zinc (35.89 ± 2.20 mg/kg dry weight) were elevated in the Yellow Spring sediment implicating galvanized metal pipe as a point source. A one-inch cross-section of the original 1920's clogged pipe subjected to nondestructive X-ray fluorescence gave a reading of 0.793% lead, also consistent with zinc-galvanized coatings. Evidence suggests that galvanized iron pipe left behind from plumbing projects is leaching Pb, Zn, and perhaps Cd into the spring water adding a significant amount of these heavy metals to the sediment over time. Exposure to the Yellow Spring sediment should be minimized or avoided since it contains significant arsenic, lead, and cadmium.