Environmental radioactivity monitoring in the surroundings of nuclear facilities is important to provide baseline data for effective detection in case of any radioactive release in the region. In this work, we report for the first time the long-term monitoring data of 137Cs and 90Sr in environmental and food samples around Qinshan Nuclear Power Plant (QNPP) in 2012-2019. The distribution levels, temporal variations and source terms of 137Cs and 90Sr in the investigated samples were discussed. The annual effective dose (AED) for the local population from the ingestion of foods was also evaluated. Peak values of 90Sr and 137Cs concentrations and 137Cs/90Sr radioactivity ratio were observed in total atmospheric deposition in 2016 and some water and food samples in the following years. This seems to be associated to an additional radioactive input, mostly likely from the operational release of a local facility. This demonstrates that 90Sr and 137Cs, especially the 137Cs/90Sr activity ratio, are sensitive indicators for detecting potential radioactive releases. Nevertheless, overall 90Sr and 137Cs activity concentrations measured during 2012-2019 in this work were at the background levels with average AED far below the internationally permissible limit and recommendation.

To evaluate the impact of the Qinshan Nuclear Power Plant (Qinshan NPP) in normal operation on the surrounding environment and population, the radioactivity levels of drinking water and the ambient environment, as well as the residents’ cancer incidence, were continuously monitored for a period of 9 years (2012-2020). All of the gross α and β radioactivity concentrations in drinking water were less than the WHO recommended values (0.5 Bq/L for gross α and 1 Bq/L for gross β). The results of ambient environment accumulated dose monitored by thermoluminescent dosimeters (TLDs) indicated that the ambient environment radioactive level around Qinshan NPP is consistently at natural background radiation levels. The age-dependent annual effective doses due to the ingestion of tap water or exposure to the outdoor ambient environment are lower than the reference dose of 0.1 mSv/y. The corresponding excess risks are at relatively low levels. Thus, the consumption of drinking water and outdoor activities are not expected to give rise to any detectable adverse effects on the health of the public around the Qinshan NPP. For all cancers combined, the age-standardized incidence rate by the Chinese 2000 standard population of the inhabitants living around Qinshan NPP is consistent with that of Zhejiang Province as a whole. No excess incidence of leukaemia was observed around the Qinshan NPP. The incidence of thyroid cancer is high and increasing, but it is also in line with the increasing trends in Zhejiang Province and all of China. Based on current radiation risk estimates, radiation exposure is not a plausible explanation for any excess cancers observed in the vicinity of the Qinshan NPP.