A Compendium of Transfer Factors for Agricultural and Animal Products

Abstract

Transfer factors are used in radiological risk assessments to estimate the amount of radioactivity that could be present in a food crop or organism based on the calculated concentration in the source medium (i.e., soil or animal feed). By calculating the concentration in the food, the total intake can be estimated and a dose calculated as a result of the annual intake. This report compiles transfer factors for radiological risk assessments, using common food products, including meats, eggs, and plants. Transfer factors used are most often selected from recommended values listed by national or international organizations for use in radiological food chain transport calculations. Several methods of estimation and extrapolation are used for radionuclides not listed in the primary information sources. Tables of transfer factors are listed by element and information source for leafy vegetables, fruit, root vegetables, grain, beef, poultry, milk, eggs, fresh and saltwater fish as well as crustaceans, mollusks, and aquatic plants. v This document was developed in conjunction with the upgrade to the GENII system of computer codes. The GENII computer code was developed to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) and the radiological risk estimating procedures of Federal Guidance Report 13 into updated versions of existing environmental pathway analysis models. GENII and the Windows compatible GENII-Version 2 provide state-of-theart, technically peer-reviewed, documented set of programs for calculating radiation dose and risk from radionuclides released to the environment. Upgrading the codes to GENII-Version 2 provided the opportunity to update and further document the library of transfer factors that support the environmental pathway analyses.

Soil-to-Plant Concentration Ratios for Assessing Food Chain Pathways in Biosphere Models

“…The transfer to the edible bulb of onions of 1 -30 is similar to the value selected by Wasiolek (2004) for "other vegetables". The alfalfa CR result range of about 50 -800 is similar to the full range reported in IAEA (1994) for grasses, and somewhat higher than used by Napier et al (2006), Staven et al (2003), or Wasiolek (2004 for "forages". The result for corn, including the leaves and cobs, is higher than the common references for "grain" -however, because the vegetative portions of the corn plant are included, the actual "grain" value is probably lower.…”

“…These values are within the ranges suggested by both IAEA (1994) and Wasiolek (2004) for forage and fodder. However, the results are somewhat higher than those used in either GENII Staven et al 2003) or RESRAD (Biwer et al 2000). These are very low values; the common environmental exposure models frequently include a contribution from soil adherence to foods (or direct soil ingestion) which overwhelms the soil-to-plant pathway (Napier 2006).…”

“…The uptake in alfalfa is in the ranges for forage/fodder reported by IAEA and Wasiolek (2004). Both are higher than used in GENII Staven et al 2003) or RESRAD (Biwer et al 2000), by substantial multiples. The CRs measured are still relatively small, but are large enough to contribute more to human food ingestion dose than the soil adherence/soil ingestion approach.…”

EMP Attachment 3 DOE-SC PNNL Site Dose Assessment Guidance

“…The transfer factors used with the CAP88-PC software are documented in Parks (1992) and Rosnick (2007). If required for comparative purposes, transfer factors used for pathway and dose calculations are also documented in GENII Version 1.485 code documentation (Napier et al 1988), Schreckhise et al 1993, andStaven et al 2003; and GENII Version 2.0 code documentation (Napier 2010).…”

Transfer factors of226Ra,210Pb and210Po from NORM-contaminated oilfield soil to someAtriplexspecies,AlfalfaandBermuda grass

“…On the other hand, natural environmental radioactivity arises mainly from primordial radionuclides, such as 40 K, and the radionuclides from the 232 Th and 238 U series and their decay products are also considered important due to their contributions to the internal radiation dose. Several studies on transfer of natural radionuclides from soil to plants have been carried out in different regions in the world (Sheppard and Evenden, 1992;Martinez-Aguirre and Perianez, 1998;Ewers et al, 2003;Staven et al, 2003;Vera Tomé et al, 2003;Pulhani et al, 2005;Blanco Rodríguez et al, 2006Al-Masri et al, 2008).…”