Assessing Metallothionein-1 Response and Heavy Metal Concentrations in Peromyscus Leucopus at the Tar Creek Superfund Site, USA

Soil SamplingSoil samples were collected from the study sites following the procedure that is described by USEPA (United States Environmental Protection Agency, 2005).A random design was used to collect soil samples from each site separately.Moreover, a meter scale was used to measure the distances between soil samples.Eight duplicate soil samples were collected from each site.Each sample was labeled as, for example, T1-1, T1-2, T2-1, T2-2, etc., where T identifies the Tar Creek Superfund Site (TCSFS), the first numeral (1-8) indicates the number of the sample, and the second numeral (1-2) points to the original or the duplicate.Samples were collected from each position with a 10% HCl acid-washed metal scoop to a depth of 18-20 cm.Samples were homogenized and weighed separately.Soil samples were dried in separate 10% HCl acid-washed and labeled polypropylene plates at room temperature for 2 weeks.Also, dried soil samples were sieved twice using the first 1 mm sieve size, No. 18 (USA Standard Test Sieve) followed by a second 250 m opening sieve (Fisher Scientific Company, Pittsburgh, PA, USA).Samples were saved in labeled acid-washed glass bottles. Sample Preparation Kidney Samples Preparation and DigestionEach kidney was subsampled by dividing it into two parts: one part was cut in a plastic petri dish placed on wet ice using a stainlesssteel scalpel to approximately one-tenth of the whole tissue.These samples were saved in plastic microtubes for metallothionein-1 analysis and returned to the freezer at -80C without thawing.The second part was saved in plastic microtubes and refrigerated at -40C prior to digestion for metal analysis.