DOI: 10.5285/8f85c188-a915-46ac-966a-95fcb1491be6
title: Element and radionuclide concentrations in wildlife (including representative species of the ICRP's Reference Animals and Plants) and associated soils from forests in north-east England, 2015-2016

description: Data comprise stable element concentrations for a range of elements, radionuclide activity concentrations for the isotopes K-40 and Cs-137 and radionuclide and stable element concentration ratios.

Samples of soil, water, vegetation (grasses, trees, herbaceous plants and shrubs), fungi, earthworms, bees, wood mice, bank voles, common frogs, frogspawn and European toads were collected between March 2015 and October 2016 from two forests in north-east England. The study was conducted to target representative terrestrial species of the ICRPs Reference Animals and Plants.

Funding for this work was via the TREE project funded by NERC, the Environment Agency and Radioactive Waste Management Ltd. under the RATE programme.
description: Data consist of stable element and radionuclide concentrations, and estimated concentration ratios for biota, soil and water collected from two forests in north-east England (March 2015 to October 2016). Samples were analysed by ICP-MS and, where sample size was sufficient, gamma analysis.

Soil: pH and loss on ignition were determined.

Water: Samples were filtered through Whatman 541 filter paper. 

Wood mice: Trapping was conducted using "Longworth" traps. Randomly selected individuals were dissected and a beetle (Dermestes maculatus) colony was used to clean the bones of soft tissue. 

Bank voles: Trapping was conducted as for Wood mice. Vole samples were ashed. 

Bee species: Pan traps were placed on the ground. Bees collected were bulked by species and homogenised in an agate mortar. 

Earthworms: Worms were collected by digging to circa 30 cm, they were rinsed in de-ionised water and placed on damp tissue paper to allow gut evacuation. Samples were bulked by species and homogenised by agate mortar. 

Common frogs and spawn: Frogs were collected by hand during darkness. Randomly selected individuals were dissected and a beetle colony used to clean bones. Spawn samples were washed in de-ionised water and freeze-dried prior to homogenisation in an agate mortar. 

European toads: Toads were collected as for frogs. Randomly selected individuals had their gastrointestinal tract removed, the remaining carcass was washed in de-ionised water and then ashed. 

Roe deer: Deer were obtained via the Forestry Commission. Animals were dissected and all bone/carcass samples were cleaned by placing in a beetle colony. Tissue samples were freeze dried and homogenised using an agate mill or mortar. 

Pine Trees: Samples were collected of small branches, needles and heartwood core (sampled using an increment borer). Samples were air dried (~20oC) and the needles and branches subsequently finely ground using an agate mill or mortar (dependent upon size); the core samples were reduced manually to ~5mm in diameter. 

Wild grasses: Samples of both leaf and flowering stems were collected. They were air dried and finely ground (using an agate mill or mortar dependent upon sample size). 
Herbaceous plants and shrubs: Opportunistic samples were collected from a variety of species abundant at the main sampling sites and from areas where the roe deer were obtained.  Samples were air dried and finely ground (using an agate mill or mortar). 

Fungi: Opportunistic samples of fungal fruiting bodies were collected mainly from areas where the roe deer were obtained. Samples were identified by species, oven dried (~60oC) and subsequently finely ground (~2mm) using either an agate mortar or "coffee" grinder depending upon sample size. Species were bulked by sampling location and, were possible, by feeding strategy. 

ICP-MS analysis was conducted using a Thermo-Fisher Scientific iCAP-Q. Samples subjected to ashing pre-treatment had undissolved black particles in the solutions which suggests digestion was incomplete. Similarly, TMAH digestion is not able to fully digest plant material therefore variable degrees of dissolution were observed; pine tree core samples showed poor dissolution rates and therefore the iodine concentrations reported may be underestimated. Digestion of replicates, reference materials and blanks were undertaken to check accuracy and precision. Detection limits were calculated as three times the standard deviation of the reagent blanks. 

Gamma analysis was conducted using hyper-pure germanium detectors calibrated for efficiency using a certified reference solution (National Physics Laboratory R08-04). Spectra were analysed using Canberra Apex software and activity concentrations decay corrected to the day of sampling. Replicate analyses were conducted on random samples and process blanks for quality assurance purposes.