Are we safe? Exploring psychological factors affecting radiation risk perception of dwellers in old uranium mining quarters

Abstract

The central region of Portugal was an important mining zone of radioactive elements, relying on radium mining until 1944 and afterwards on uranium mining until 2000. With the dissolution of the Soviet Union in 1991, uranium mined by former member states flooded the market. Both the ensuing price drop and the exhaustion of mines led to the end of Portuguese uranium mining. Historic records show that economic and social benefits in that region overshadowed radiation risk perception. This article looks at ways to strengthen expertise and raise public awareness of radiological risk amongst dwellers in old uranium mining quarters. Some psychological factors are known to influence radiation risk perception and help explain the reaction of dwellers in homes built with uranium mining tailings. Exploration of these factors with a mental models approach and focus groups is necessary to raise the population's risk awareness, promote the adoption of safe behaviours regarding indoor radon risk and other ionising radiation risks, and answer the question of whether we are safe.

1. INTRODUCTION

Radon, a cancer-causing element, is a radioactive gas that emanates from rocks and soils and tends to concentrate in enclosed spaces such as underground mines or houses. Since 1977, the International Commission on Radiological Protection (ICRP) has made recommendations for the protection of people against exposure to radon at home and at work (ICRP, 2018). The World Health Organization (WHO) called attention to health effects from residential radon exposures in 1979 and classified radon as a human carcinogen in 1988 (WHO, 2009). The International Radon Project (WHO, 2007) was published to identify effective strategies for reducing the deleterious effects of indoor radon on human health and raise public and political awareness about the consequences of long-term exposure to radon. Remediation works of old uranium mines in the central region of Portugal began in 2005 to reduce radon and other radioactive elements’ risks.

According to WHO, by 2009 radon was the second largest cause of lung cancer. Radon risk perception is critical for the adoption of safety behaviours and has been the focus of research worldwide (Hevey, 2017; Lopes et al., 2021; Cori et al., 2022). This article argues for the need to explore a number of psychological factors identified as affecting radiation risk perception of dwellers in old uranium mining quarters in the central region of Portugal.

1.1. Radium and uranium mining, decommissioning, and remediation

The first mining work on Portuguese uraniferous ore deposits dates from 1907 (Serra and Peiriço, 2006). A mining company linked to Marie Curie discovered uranium deposits in the central region of Portugal, and the extraction of radioactive materials in that region lasted around 90 years (Cameron, 2016). In 1951, the Portuguese Radium Company expanded the business and installed a chemical treatment plant in Urgeiriça for producing uranium oxide (U₃O₈) making it the nexus of dozens of mines. Meanwhile at Urgeiriça products from mine tailings were used to build houses for the workers as well as the local roads. Around 1990, with the significant devaluation of uranium in the raw materials market, the – by then – state-owned company laid off most workers (Garcia, 2019).

Site remediation of uranium mines in Urgeiriça began together with the MinUrar project, a scientific report that measured health effects from radiation exposure of dwellers outside uranium mining quarters (Marinho-Falcão et al., 2005). This report was key to moving from the concept of contaminated land to contaminated bodies in dwellers living at the uranium mining quarters in homes built with uranium mining tailings (Mendes and Araújo, 2010).

1.2. Reappearance of radiation risk perception from uranium

During the Kosovo War (1998–1999), the suspicion was raised that soldiers in the Balkans could be contaminated with depleted uranium, due to its use in ammunition. The Portuguese Ministry of Science and Technology commissioned a scientific field mission to the Balkans to collect samples in the places where the Portuguese soldiers were stationed. Analysing these samples and information collected in loco, the report concluded that there was no contamination among the soldiers (DPRSN, 2001). Nonetheless, news about the mission had a significant impact on behaviours arising from radiation risk perception, especially in former uranium mining workers who were able to get media attention in turn: ‘so they are studying uranium contamination in Bosnia, in Kosovo, and we who had our uranium mines here? People can be infected, they can be sick’.

In 2001, the matter was taken to the Portuguese Parliament, which in turn recommended that the executive power carry out a study to find out if there was any influence on people's health due to living near the old uranium mines. The resulting parliament resolution also recommended concrete measures to solve the problem of radioactivity adopting concrete solutions on the perimeter of the Urgeiriça mines (Resolution of the Assembly of the Republic, 2001). As such, this epoch marks the beginning of a publicly debated, more collectively assumed, conscience and awareness of the risks linked to mining activities of radioactive materials.

1.3. Radiation risk near the uranium mines

In 1976, radioactive contamination was detected in sediments of a stream by effluents from the Urgeiriça mine, although this did not affect the food grown along the stream's route. Contamination with radium-226 in watercress cultivated in the Freixiosa mine, and in some waters, justified the continuation of studies in these mines of the central region of Portugal (Trindade-Elias and Ribau-Teixeira, 1979).

Around 30 years later, and although the radioactive contamination problems were already known, the MinUrar project substantiated the claim for social and working rights by uranium mine former workers. Additionally, the association of former uranium mine workers used the report to force the uranium mining company to pay compensation to the workers and their families, resulting in the implementation of a wider system of social and radiological protection of the population exposed to indoor radon risk (Mota-Veiga, 2014).

2. METHODS AND RESULTS

The case study of Urgeiriça pertaining to radiation risk perception during uranium mining, decommissioning, and remediation was presented at RICOMET 2022 (Melo et al., 2022). Couples’ interviews were analysed through the lenses of risk perception theories (Starr, 1969; Sjöberg, 2000; Fox-Glassman and Weber, 2016), which aim to address why, how, and when we feel safe. Psychological factors known to affect radiation risk perception were explored among dwellers in old uranium mining quarters. Some of these factors can be classified as (a) decreasing risk perception, e.g. familiarity with uranium mining activities and voluntariness to work in the uranium mining industry, and (b) increasing risk perception, e.g. fear, media attention, and seriousness of effects through cases of cancer.

Scientific certainty which in the literature is related to lowering risk perception in this case increased it. Furthermore it enabled compensation for involuntary risk exposure and new legislation regarding mandatory health monitoring, that is, retirement after 55 years of age for former workers outside the mine, environmental remediation, and radiological decontamination of the houses.

Historiographic analyses of documents, records, and archives were complemented with interviews with former workers living in uranium mining quarters, in order to study their radiation risk perception and explore the psychological factors involved.

Two couples, who bought their homes in the mining quarters from the uranium mining company, were visited and asked about their risk perception. Visits were made in November 2019, when their homes had just been remediated, and again in January 2023. On the second visit, a guided tour of the old mining facilities was also arranged with a worker from the mining remediation company at Urgeiriça to see the newly finished remediation works at the mining installations. Regarding dwellers’ risk perception, one couple had agreed with the decontamination work done and received a document declaring their home had been decontaminated. The certificate could be used if they want to sell their house. Nevertheless, the other couple did not feel that the decontamination works were sufficient in their home, and awaited further decontamination works at the time of the second visit.

Before remediation, the activity concentration levels of radon-222 in the kitchen of one of the interviewees, a former locksmith at the mining company, reached values of 5000 Bq m⁻³ when the maximum acceptable legal exposure level in Portugal was 400 Bq m⁻³ at the time. The current value, 300 Bq m⁻³, was established in 2018 by decree law (Decree of the President of the Republic, 2018) and implemented through the National Plan for Radon (Council of Ministers Resolution, 2022). Another interviewee, a former secretary of the company's administration facing a similar scenario, actively participated in a long battle against the mining company for involuntary risk exposure compensation. Both couples still live in old uranium mining quarters, and one of the couples has their children also living with them.

Within this scope a subsidiary question arose, whether dwellers in old uranium mining quarters would rather be relocated rather than continue living in their homes and go through the remediation process.

In August 2023, another visit to Urgeiriça allowed a search for an answer to that question by talking with dwellers who were active members of the association of former uranium mine workers. A guided tour to old uranium mining remediated installations was organised. One of the dwellers participating in the visit expressed that the remediation works were partially satisfactory, but that further remediation was necessary to attract more investment in the region. Another dweller would have preferred to receive monetary compensation and move to another place, but such an option was not provided. Dwellers hoped that the visitors centre and uranium mining museum, announced by the mine remediation company, proceeds and will keep alive the memories of those who have lived, and those who still live, at the legacy site.

The current article's title was issued as a command in GPT-4 and Bard, large language models. Neither artificial intelligence models mention mining tailings nor radon risk. Asking artificial intelligence models the alternative question ‘What can you tell me about living in old uranium mining quarters?’ yielded more specific results. As an example, Bard mentioned the risk of radon gas exposure, whereas GPT-4 did not. The search for answers in these models enabled us to assume that the specific risks inherent to the use of uranium mining tailings are neither common knowledge nor covered by these models.

3. CONCLUSIONS

Although uranium mines in the central region of Portugal are now legacy sites where some of the remediated installations’ future use is still under discussion, several dwellers of old uranium mining quarters do not see the possibility of living anywhere else but in their homes, which they bought from the mining company. With insight into the legacy of the mining activity of radioactive elements, the dwellers hope for a similar fair remediation of their homes.

The results reinforce the importance of the present research, based on mental models and focus groups, for the exploration of psychological factors. Such approaches are necessary to raise the population's risk awareness, promote the adoption of safe behaviours regarding indoor radon risk and other ionising radiation risks, and answer the question of whether we are safe.