Environmental transfer parameters of strontium for soil to cow milk pathway for tropical monsoonal climatic region of the Indian subcontinent

Abstract

The radionuclide transfer between compartments is commonly described by transfer parameters representing the ratio of concentrations of an element in two compartments for equilibrium conditions. This is a comprehensive study on the soil-to-grass transfer factor (Fv) and grass-to-cow milk transfer coefficient (Fm) for stable strontium (Sr) for soil-grass (pasture)-cow (Bos taurus) milk environmental pathway under field conditions for a high rainfall tropical monsoonal climatic region of the Indian subcontinent. The study was conducted in the vicinity of the Kaiga nuclear power plant (NPP), situated ~ 58 km inland of the West Coast of the Indian subcontinent. A grass field was developed exclusively for this study, and two cows of the native breed were raised to graze on it. The soil, grass, and milk were analyzed to evaluate the Fv and the Fm values for the stable Sr. For comparison, several pasture lands and the cows raised by the villagers and a dairy farm were also studied. The Fv values were in the range 0.18—8.6, the geometric mean (GM) being 1.8. The correlations of Fv values with a range of physicochemical parameters are presented. The GM values for Fm were 2.2 × 10–3 d L-1 and 7.2 × 10–3 d L-1 for the two cows raised for this study, 2.6 × 10–3 d L-1 for those raised by the villagers, and 4.2 × 10–3 d L-1 for the dairy farm. The site-specific Fm value for the region was determined as 3.2 × 10–3 d L-1. The concentration ratio (CR), defined as the ratio of Sr concentration in milk to that in feed under equilibrium conditions, exhibited less variability (1.8 × 10–2—5.4 × 10–2) among the three categories of cows.

Scalable Dialysis-Based Method for the Isolation of Strontium from Milk for Radioanalysis

“…In addition, strontium exhibits a high degree of environmental mobility that rivals, and in some cases exceeds, that of cesium. − It is also environmentally persistent, with effective (i.e., integrated) environmental half-lives of 1.8–2.1 and 8–10 y found in the short (2–3 y) and long (30 y) terms, respectively, from Austrian data following the cessation of fallout from atmospheric nuclear weapons testing . With these considerations, a comprehensive and timely evaluation of 90 Sr contamination in environmental and foodstuff samples serves as a key input to decisions affecting land management and human health due to exposure following a nuclear release. − Among sample types, cow milk (henceforth simply referred to as milk) is one of the most relevant environmental markers owing to its dietary prevalence, the large geographical area represented by a single sample, and the high degree to which radionuclides of iodine, cesium, and strontium are incorporated. − However, the analysis of 90 Sr in milk can be exceedingly laborious since strontium and/or its yttrium progeny must be chemically isolated before measurement owing to the nature of beta particle emission and the potential for spectral and isobaric interferences …”