Assessment of 232Th, 226Ra, 137Cs, and 40\xa0K concentrations and annual effective dose due to the consumption of Vietnamese fresh milk

Van-Hao Duong,Edit Tóth-Bodrogi,Miklós Hegedűs,Thanh-Duong Nguyen,Tibor Kovács

doi:10.1007/s10967-021-07643-w

Abstract

Vietnam has little data on radionuclide concentrations in milk, despite steadily increasing domestic consumption. Eight milk brands were investigated by gamma-spectrometry, and the resulting ingestion dose was calculated. The 232Th, 226Ra, 137Cs, and 40K concentrations varied from 0.60 ± 0.19 to 1.21 ± 0.24, 1.45 ± 0.18 to 2.45 ± 0.24, below detection limit to 0.13 ± 0.06, and 341 ± 6 to 387 ± 7 Bq/kg (dry w.t). The total average Annual Effective Dose for all age groups were similar for all brands, and concentrations are far less than the WHO guidance level. All brands are safe for consumption.

Highlights

The humans are often exposed to natural and artificial radionuclides, which can enter the human body through breathing, eating, and drinking
The results showed that smallest activity concentration belongs to the artificial radionuclide, 137Cs, 0.13 ± 0.06 (Bq/ kg) was found in VN milk and all other milk samples had activity concentrations below the detection limit (BDL)
The low 137Cs activity concentration in milk samples could be explained by low 137Cs activity concentration in soil which was reported to be 3.82 Bq/kg in surface soil (0–20 cm from surface) [24] before the Fukushima accident; the low 137Cs activity concentration in water; the reduction due to the transfer processes from soil to grass, and from grass and water to cow milk

Summary

Introduction

The humans are often exposed to natural and artificial radionuclides, which can enter the human body through breathing, eating, and drinking. Milk is one of the fundamental foodstuffs for humans, especially for infants, children and old people. Evaluating and monitoring the level of radionuclides in milk (fresh and powdered) play an important role in estimating the annual effective dose for the population. The radionuclides in milk have received much attention from researchers in many parts of the world. In Nigeria, a report showed unusually high average activity concentrations of 40K compared to other reported values, reaching 831.6 ± 53.8 Bq/kg [2]. For powdered milk in Brazil, Melquiades & Appoloni [3] indicated that the activity of 40K (475 ± 12 for polly and 489 ± 13 for cativa) was usual for powdered milk, while the observed 137Cs and 232Th activity concentrations were comparatively small.

Methods

Results

Conclusion