Evaluation and equity audit of the domestic radon programme in England

Characterization of Colorado residents and radon reduction behaviors through latent class analysis and path models

Radon is a naturally occurring radioactive gas that enters homes through cracks in the foundation where accumulated levels can cause lung cancer. Within the United States (U.S.), state level radon reduction strategies rely on education and outreach to motivate people to test and mitigate their home. Only about 5% of the housing units in Colorado, U.S. have been tested for radon. This study looks at the 2012 Behavioral Risk Factors Surveillance System (BRFSS) in Colorado to identify distinct groups of people using Latent Class Analysis, and compares radon awareness, testing, and mitigation to understand underlying differences of radon reduction behaviors using path models. Five classes were identified: 1) Wealthy Young Families, 2) Older Singles, 3) Empty Nesters, 4) Smokers, and 5) Struggling Young Families. Significant differences in responses to radon survey questions existed across groups in which Struggling Young Families were the least likely to be aware of radon, have tested their home for radon, and have their home mitigated. Average radon awareness, testing, and mitigation appeared to be influenced by financial stress. Results from this study can be used to tailor future radon interventions and policy initiatives to enhance equity of radon reduction behaviors including legal framework to ensure radon mitigation takes place in rental properties.

The efficacy of public health information for encouraging radon gas awareness and testing varies by audience age, sex and profession

Radioactive radon inhalation is a leading cause of lung cancer and underlies an ongoing public health crisis. Radon exposure prevention strategies typically begin by informing populations about health effects, and their initial efficacy is measured by how well and how fast information convinces individuals to test properties. This communication process is rarely individualized, and there is little understanding if messages impact diverse demographics equally. Here, we explored how 2,390 people interested in radon testing differed in their reaction to radon's public health information and their subsequent decision to test. Only 20% were prompted to radon test after 1 encounter with awareness information, while 65% required 2-5 encounters over several months, and 15% needed 6 to > 10 encounters over many years. People who most delayed testing were more likely to be men or involved in engineering, architecture, real estate and/or physical science-related professions. Social pressures were not a major factor influencing radon testing. People who were the least worried about radon health risks were older and/or men, while negative emotional responses to awareness information were reported more by younger people, women and/or parents. This highlights the importance of developing targeted demographic messaging to create effective radon exposure prevention strategies.

Cost-effectiveness of radon remediation programmes in the UK in the 2020s

Radon, a gaseous radioactive decay product of naturally-occurring uranium is widely distributed in the environment in rocks and soils and, in certain circumstances, can accumulate in the built environment. Initial studies confirmed a direct link between exposure to both radon gas and its short-lived radioactive progeny, and increased lung-cancer incidence, and demonstrated that radon levels in domestic housing can be sufficiently high to expose occupants to increased risk of lung-cancer. Subsequent studies worldwide have shown that it is cost-effective to detect and reduce domestic radon levels in order to reduce this risk. Recent advances in the early detection of lung-cancer, coupled with the development of improved treatment procedures, have progressively improved survival from the disease, with the numbers surviving at 5 years doubling over recent years, during which period the real costs of lung cancer treatment have risen by around 30%. In the meantime, however, in addition to radon and tobacco-smoke, other airborne pollutants have been identified as risk-factors for lung-cancer. This paper reviews both these actual developments and anticipated future trends, and concludes that since these advances in diagnosis and treatment of lung-cancer have had only a modest effect on cost-effectiveness, it is still important to conduct radon monitoring and remediation programmes. While the general increase in life-expectancy improves the cost-effectiveness of radon remediation programmes significantly, reducing tobacco-smoking incidence reduces that cost-effectiveness but with the overall benefit of reducing radon-related lung-cancers. The challenge remains of encouraging affected householders to remediate their homes to reduce radon levels.

A Comparative Study of Radon Levels in Federal Buildings and Residential Homes in Canada

Shortly after revision of the Canadian radon guideline from 800 to 200 Bq m, Health Canada established the Federal Building Testing Program in 2007 to demonstrate federal leadership in raising awareness about radon risk and the need for testing. By the end of 2017, more than 7,600 federal workplaces had been tested for radon. As is the case in all radon surveys, radon levels vary widely; federal building results ranged from below the detection limit to more than 2,500 Bq m in a few rooms of a few buildings. Weighted by the population of federal public servants across Canada, the average radon distribution in federal workplaces has a geometric mean of 22.0 Bq m with a geometric standard deviation of 2.3. The population-weighted arithmetic mean is 34.3 Bq m, significantly lower than the population-weighted average radon concentration of 72.9 Bq m in residential homes across Canada. On average, 2% of federal workplaces have radon concentrations above 200 Bq m, which is also significantly lower than the 7% of residential homes that tested above 200 Bq m. This comparative study demonstrated clearly that radon education and awareness in Canada should focus more on residential testing and remediation actions to effectively reduce the burden of radon-induced lung cancer.

Exploring the relationship between social deprivation and domestic radon levels in the East Midlands, UK

The natural radioactive gas radon is widely present in the built environment and at high concentrations is associated with enhanced risk of lung-cancer. This risk is significantly enhanced for habitual smokers. Although populations with higher degrees of social deprivation are frequently exposed to higher levels of many health-impacting pollutants, a recent study suggests that social deprivation in the UK is associated with lower radon concentrations. The analysis reported here, based on published data on social deprivation and domestic radon in urban and rural settings in the English East Midlands, identifies a weak association between increasing deprivation and lower radon areas. This is attributed to the evolution of the major urban centres on low-permeability, clay-rich alluvial soils of low radon potential. In addition, the predominance of high-rise dwellings in towns and cities will further reduce average exposure to radon in populations in those areas.

An assessment of the effectiveness of UK building regulations for new homes in Radon Affected Areas

Radon, a naturally occurring radioactive gas generated underground by radioactive decay of nuclides contained in certain types of rocks, can concentrate inside buildings, where it poses the second-largest risk factor for lung cancer, after smoking. The highest concentrations of domestic radon in the UK occur in the south-western counties of Devon and Cornwall, but certain areas in Northamptonshire and surrounding counties in the English Midlands also have high levels. It has been shown that it is possible both to reduce the radon concentrations in existing houses and to build new homes with appropriate protection. Since 1999, the UK's Building Regulations have specified that all new homes should be built with a combined radon-proof/damp-proof membrane plus, in Radon Affected Areas, a sump under the building. However, the building regulations do not require that the radon level is measured once the house is built and so there is little information on the effectiveness of these measures. Builders generally do not mention radon, and when asked, just confirm that their houses are built to current standards. To better understand the efficacy or otherwise of the currently mandated radon-protection measures, a cross-sectional investigation was carried out in 26 new housing developments in high-radon areas in Northamptonshire. In a targeted mail-shot, 1056 householders were invited to apply for a free radon test; 124 replied (11.7%). In total, 94 pairs of detectors were returned (70.1% of responders), of which two were spoiled, giving a total of 92 results. Following processing and seasonal correction, the arithmetic mean radon concentration in the target houses was 45% of the arithmetic mean radon concentration in existing houses in the postcode sectors where the houses were built and were approximately log-normally distributed. No results exceeded the UK Action Level of 200 Bq. m^-3 but three were above the Target Level of 100 Bq. m^-3. The results suggest that the radon-proof membranes in general ensure that radon concentrations in new homes constructed in accordance with the Building Regulations in Radon Affected Areas (RAAs) are satisfactorily low. However, there is a very small statistical probability that levels in a small number of homes will be close to or above the Action Level, particularly in areas of high radon potential. As a result, the Public Health England (PHE) recommendation for testing in the first year of occupation should be adopted as a legal requirement.

Radon Risk and Remediation: A Psychological Perspective

Although radon exposure in the home increases the risk of lung cancer, this risk can be managed. However, evidence indicates that testing for radon and subsequent home remediation rates are generally low in many countries. The present perspective outlines some key insights from psychological science that might account for sub-optimal radon protection. Psychological aspects of how the health risks posed by radon are perceived and managed are outlined. There is need to consider radon risk perception in terms of the (a) cognitive and emotional responses to radon and (b) social context in which the radon threat occurs. In addition, the nature of the threat itself is integral to the failure for people to act in response to a radon threat. Finally, the challenges arising from defensive processing of radon threat information are outlined.

Small area mapping of domestic radon, smoking prevalence and lung cancer incidence--A case study in Northamptonshire, UK

Smoking and radon both cause lung cancer, and together the risk is significantly higher. UK public health campaigns continue to reduce smoking prevalence, and other initiatives identify houses with raised radon (radon-222) levels and encourage remedial action. Smoking prevalence and radon levels in the UK have been mapped at Primary Care Trust level. This paper extends that work, using a commercial socio-demographic database to estimate smoking prevalence at the postcode sector level, and to predict the population characteristics at postcode sector level for 87 postcode sectors in Northamptonshire. Likely smoking prevalence in each postcode sector is then modelled from estimates of the smoking prevalence in the different socio-economic groups used by the database. Mapping estimated smoking prevalence, radon potential and average lung cancer incidence for each postcode sector suggested that there was little correlation between smoking prevalence and radon levels, as radon potential was generally lower in urban areas in Northamptonshire, where the estimates of smoking prevalence were highest. However, the analysis demonstrated some sectors where both radon potential and smoking prevalence were moderately raised. This study showed the potential of this methodology to map estimated smoking prevalence and radon levels to inform locally targeted public health campaigns to reduce lung cancer incidence.

Future initiatives to reduce lung cancer incidence in the United Kingdom: smoking cessation, radon remediation and the impact of social change

Aims:

Smoking and radon cause lung cancer, with smoking being the more significant risk factor. Although programmes to identify UK houses with raised radon levels and to encourage remedial action started in 1990, uptake has been limited and those most at risk, smokers and young families, are not being reached. The risks from smoking and radon are multiplicative. Public health campaigns have reduced smoking prevalence significantly. Since most radon-induced lung cancers occur in smokers, reducing the number of smokers will reduce the number of radon-induced lung cancers. This article considers the impact of reducing smoking prevalence on the effectiveness of radon remediation programmes, combining this with demographic trends and regional variations to assess implications for future public health.

Methods:

Results on cost-effectiveness of smoking cessation and radon remediation programmes were combined with government figures for smoking prevalence to estimate the number of cancers averted and the cost-effectiveness of such programmes, taking into account demographic changes, including increasing life expectancy. Regional variations in smoking prevalence and smoking cessation programmes were reviewed, comparing these to the geographic variation of radon.

Results:

The continuing impact of smoking cessation programmes in reducing smoking prevalence will reduce the number of radon-induced lung cancers, but with a lag. Smoking cessation programmes are more cost-effective than radon remediation programmes, presenting an additional opportunity to reduce radon risk to smokers. Regional data show no correlation between smoking prevalence and radon levels.

Conclusions:

Reduced smoking prevalence reduces the effectiveness of radon remediation programmes. This, coupled with limited uptake of radon remediation, suggests that radon remediation programmes should be targeted, and that an integrated public health policy for smoking and radon is appropriate. Lack of correlation between smoking prevalence and radon suggests that local assessment of relative priorities for public health strategies, such as the ‘Total Place’ initiative, is appropriate.

The cost effectiveness of radon reduction programmes in domestic housing in England and Wales: the impact of improved radon mapping and housing trends

In the UK, excessive levels of radon gas have been detected in domestic housing. Areas where 1% of existing homes were found to be over the Action Level of 200Bq·m(-3) were declared to be Radon Affected Areas. Building Regulations have been introduced which require that, for areas where between 3% and 10% of existing houses are above the Action Level, new homes should be built with basic radon protection using a membrane, and that, where 10% or more of existing homes exceed this level, new homes should be built with full radon protection. Initially these affected areas followed administrative boundaries, known as Counties. However, with increasing numbers of measurements of radon levels in domestic homes recorded in the national database, these areas have been successively refined into smaller units - 5km grid squares in 1999, down to 1km grid squares in 2007. One result is the identification of small areas with raised radon levels within regions where previously no problem had been identified. In addition, some parts of areas that were previously considered radon affected are now considered low, or no, risk. Our analysis suggests that the net result of improved mapping is to increase the number of affected houses. Further, the process is more complex for local builders, and inspectors, who need to work out whether radon protection in new homes is appropriate. Our group has assessed the cost-effectiveness of radon remediation programmes, and has applied this analysis to consider the cost-effectiveness of providing radon protection in both new and existing homes. This includes modelling the potential failure rate of membranes, and whether testing radon levels in new homes is appropriate. The analysis concludes that it is more cost effective to provide targeted radon protection in high radon areas, although this introduces more complexity. The paper also considers the trend in housing to a greater proportion of apartments, the regional variations in types of housing and the decreasing average number of occupants in each dwelling, and concludes that data and methods are now available to respond to the health risks of radon at a local level, in keeping with a general initiative to prioritise responses to health and social welfare issues at a more local level.

Lung cancer risk from radon in Ontario, Canada: how many lung cancers can we prevent?

Purpose

To calculate the burden of lung cancer illness due to radon for all thirty-six health units in Ontario and determine the number of radon-attributable lung cancer deaths that could be prevented.

Methods

We calculated the population attributable risk percent, excess life-time risk ratio, life-years lost, the number of lung cancer deaths due to radon, and the number of deaths that could be prevented if all homes above various cut-points were effectively reduced to background levels.

Results

It is estimated that 13.6 % (95 % CI 11.0, 16.7) of lung cancer deaths in Ontario are attributable to radon, corresponding to 847 (95 % CI 686, 1,039) lung cancer deaths each year, approximately 84 % of these in ever-smokers. If all homes above 200 Bq/m³, the current Canadian guideline, were remediated to background levels, it is estimated that 91 lung cancer deaths could be prevented each year, 233 if remediation was performed at 100 Bq/m³. There was important variation across health units.

Conclusions

Radon is an important contributor to lung cancer deaths in Ontario. A large portion of radon-attributable lung cancer deaths are from exposures below the current Canadian guideline, suggesting interventions that install effective radon-preventive measures into buildings at build may be a good alternative population prevention strategy to testing and remediation. For some health units, testing and remediation may also prevent a portion of radon-related lung cancer deaths. Regional attributable risk estimates can help with local public health resource allocation and decision making.

Influences motivating smokers in a radon-affected area to quit smoking

AIMS

Domestic radon gas concentrations in parts of the UK are sufficiently high to increase lung cancer risk among residents, and recent studies have confirmed that the risk of smokers developing lung cancer is significantly enhanced by the presence of radon. Despite campaigns encouraging residents of radon-affected areas (RAEs) to test and remediate their homes, public response to the risks posed by radon remains relatively modest, particularly among smokers and young families, limiting the health benefits and cost-effectiveness achievable by remediation. The observation that smokers, who are most at risk from radon, are not explicitly targeted by current radon remediation campaigns prompted an assessment of the value of smoking-cessation initiatives in reducing radon-induced lung cancers by reaching at-risk subgroups of the population hitherto uninfluenced by radon-awareness programmes. This study addresses the motivation of current quitters in a designated RAE using a postal questionnaire administered around one year after the cessation attempt.

METHODS

Residents of the Northamptonshire RAE who had joined the smoking-cessation programme between July and September 2006 and who remained verifiably tobacco free at four weeks, were subsequently invited to participate in a questionnaire-based investigation into factors affecting their decision to cease smoking. From an initial population of 445 eligible individuals, 205 of those contacted by telephone after 12 months agreed to complete postal questionnaires, and unsolicited questionnaires were sent to a further 112 participants for whom telephone contact had proved impossible. One hundred and three completed questionnaires were returned and analysed, the principal tools being χ(2) , Mann-Whitney and Kruskal-Wallis tests.

RESULTS

Individuals decide to quit smoking from self-interest, principally on health grounds, and regard the effects of their smoke on others, particularly children and unborn babies, as less significant. The risk of developing respiratory, coronary/cardiac or cancerous conditions provides the greatest motivation to the decision to quit, with knowledge of radon among the lowest-ranked influences.

CONCLUSIONS

This study confirms that quitters place risks to their personal health as the highest factors influencing their decision to quit, and health professionals should be aware of this when designing smoking-cessation initiatives. As radon risk is ranked very low by quitters, there would appear to be the potential to raise radon awareness through smoking-cessation programmes, with the objective of increasing the uptake and success rate of such programmes and encouraging participation in radon-remediation programmes.