Evaluating the health benefits and cost-effectiveness of the radon remediation programme in domestic properties in Northamptonshire, UK

Although previous analysis of health benefits and cost-effectiveness of radon remediation in a series of houses in Northamptonshire suggested that testing and remediation was justified, recent results indicate fewer predicted affected houses than previously assumed. Despite numerous awareness campaigns, limited numbers of householders have tested their homes, only a minority of affected householders have remediated, and those most at risk generally fail to remediate. Moreover, a recent survey shows a wide range of public perception of radon risk, not significantly influenced by public health campaigns. These observations impact our previous analysis, which has been reviewed in the light of these observations. Following the declaration of Northamptonshire, UK, as a radon Affected Area in 1992, a series of public awareness campaigns encouraged householders to assess domestic radon levels and, if appropriate, to take action to reduce them. Despite these awareness campaigns, however, only moderate numbers of householders have taken remediatory action. The costs of such remedial work in a series of domestic properties in Northamptonshire, the radon level reduction achieved, and the resultant heath benefit to the residents, have been the subject of study by our group for some years. Previous analysis, based on estimates of the total number of affected houses derived from the National Radiological Protection Board (NRPB) test data for the area, suggested that a programme of testing and remediation in Northamptonshire could be justified. The NRPB has continued to initiate and to collate radon testing, and published further results in 2003. These results include revised predictions of the numbers of affected houses, now considered to be less than the numbers previously assumed. More recently, the availability of the European Community Radon Software (ECRS) has permitted calculation of individual, rather than population-average, risk, demonstrating that those most at risk are generally those who do not take action. In addition, a recent survey of risk perception shows an extremely wide range of public perception of radon risk, a perception that has not been significantly altered by public health campaigns. These predictions have profound effects, both on our previous analysis, particularly since only limited numbers of householders test their homes and even fewer remediate if they discover raised levels, and also on the public health strategies for this risk.     

Lowering the UK domestic radon Action Level to prevent more lung cancers--is it cost-effective?

Case studies have shown that radon gas can accumulate within domestic properties at sufficiently high levels that it can cause lung cancer, and recent studies have suggested that this risk remains significant below the UK domestic Action Level of 200 Bq m(-3). Raised radon levels can be reduced by engineering measures, and it has been shown that domestic radon remediation programmes in UK Affected Areas can result in reduced risks to the population and can be cost-effective. We consider here the benefits and costs of the domestic radon remediation programme in Northamptonshire, UK, and consider the implications for that programme of reducing the UK Action Level below its present value. A radon remediation programme based on an Action Level above 200 Bq m(-3) will cost less and will target those most at risk, but will be less cost-effective and will lead to higher residual dose and greater risk of cancer in the remaining population. Reducing the Action Level below 200 Bq m(-3) will prevent more cancers, but at significantly higher cost. It will also be less cost-effective, because remediation of a significant number of houses with moderate radon levels will provide only a modest health benefit to occupants. Overall, a completed radon remediation programme of the type implemented in Northamptonshire is most cost-effective for an Action Level between 200 and 300 Bq m(-3). The implications for future health policy are discussed.     

Effects of residential mobility on individual versus population risk of radon-related lung cancer.

The U.S. Environment Protection Agency (EPA) does not consider the effects of normal patterns of residential mobility in estimating individual radon-related lung cancer risks. As a consequence, the EPA's population risk estimates may have little bearing on individual risks, and remediation of high-radon homes may have only small health benefits for the individual who remediate their homes. Through a stimulation analysis, we examine the effects of residential mobility on random exposure and lung cancer risk. Given normal mobility, only 7% of eventual radon-related mortality among current 30 year old will occur in the 5% currently living in homes above pCi/l (the EPA's action level for remediation) in contrast with you estimate of 31% of deaths when mobility's ignored. About 10 pCi/l the no-mobility assumption implies 10.3% of deaths, compared to only 0.4% when mobility taken into account. We conclude that knowledge of one's current random exposure not necessarily a useful guide to one's risk, especially for residents of the high-radon homes targeted for remediation by the EPA. The risk of such individuals is like to be substantially lower than that implied in the EPA's risk charts. If people currently living in high radon homes remediate their houses, the majority of the resulting health benefits will accrue to future occupants of their homes.     

The Castleisland Radon Survey-follow--up to the discovery of a house with extremely high radon concentrations in County Kerry (SW Ireland).

In July 2003, a house with a seasonally adjusted annual average radon concentration of 49 000 Bq m(-3) was identified near Castleisland in County Kerry (SW Ireland). The possibility that other houses with similar extreme radon concentrations could be present in the surrounding area triggered the setting up of a localised radon survey, the so-called 'Castleisland Radon Survey' (CRS). To this end, approximately 2500 householders living in four 10 x 10 km2 grid squares from the Irish grid closest to the town of Castleisland were invited to participate. Four hundred and eighteen householders responded to the invitation (17% response rate) and 383 home results were used for further analysis. In the 400 km2 encompassing the four studied grid squares, 14% of the homes were found to have a seasonally adjusted annual average radon concentration above the national reference level of 200 Bq m(-3) while 2% above 800 Bq m(-3). An average radon concentration of 147 Bq m(-3) was calculated. This can be compared with the average radon concentration of 98 Bq m(-3) calculated for the same four grid squares on the basis of 80 measurements carried out during the Irish National Radon Survey (NRS) which was conducted between 1992 and 1997. The fourth highest radon concentration (6184 Bq m(-3)) and three of the ten highest ever measured in Ireland were all identified during the CRS. This shows that localised and targeted radon surveys are an invaluable tool for the identification of homes at highest risk from high radon concentrations. Two of the four grid squares investigated during the CRS are currently designated as high radon areas (defined as areas where 10% or more of all houses are predicted to exceed 200 Bq m(-3)) as predicted by the NRS. A thorough statistical analysis of the CRS and NRS data was carried out and indicated that both datasets could be merged and used to refine the original NRS predictions. The results indicate that two of the four studied grid squares could potentially be redesignated. The practical feasibility and overall benefit of updating the Irish radon map in light of this analysis is described.     

The impact of declining smoking on radon-related lung cancer in the United States

Objectives. We examined the effect of current patterns of smoking rates on future radon-related lung cancer.Methods. We combined the model developed by the National Academy of Science''s Committee on Health Risks of Exposure to Radon (the BEIR VI committee) for radon risk assessment with a forecasting model of US adult smoking prevalence to estimate proportional decline in radon-related deaths during the present century with and without mitigation of high-radon houses.Results. By 2025, the reduction in radon mortality from smoking reduction (15 percentage points) will surpass the maximum expected reduction from remediation (12 percentage points).Conclusions. Although still a genuine source of public health concern, radon-induced lung cancer is likely to decline substantially, driven by reductions in smoking rates. Smoking decline will reduce radon deaths more that remediation of high-radon houses, a fact that policymakers should consider as they contemplate the future of cancer control.The Environmental Protection Agency (EPA) estimates that radon in the home is responsible for over 21 000 lung cancer deaths annually among Americans, making radon the major cause of lung cancer after tobacco use. The agency considers radon a major public health problem and, since 1986, has mounted an aggressive campaign urging the public to test their homes for radon and take remedial actions when airborne concentrations of radon exceed 4 picocuries per liter of air (4 pCi/L).¹For its most current risk assessment, the EPA employed the BEIR VI model, developed by the Committee on Health Risks of Exposure to Radon (the BEIR VI committee) of the National Academy of Sciences (NAS).² The BEIR VI model''s calculation of radon-related risk (as was the case for its predecessor, BEIR IV) was estimated from data on miners, who are subject to much higher levels of radon than is the average population and have shown a significant correlation between lung cancer risk and radon exposure. Although the extrapolation of the results from miners to the much less exposed general public initially caused controversy, the BEIR VI implications of risk have been validated by recent case–control studies at the population level.^3–5 The BEIR VI model is thus broadly accepted as a valid predictor of the radon-related risk for typical individuals.The available data suggest a strong interaction effect between radon exposure and smoking status in the determination of lung cancer risk, which means that smokers are at a much higher risk of dying from radon-induced lung cancer than are nonsmokers. This interaction is recognized in the BEIR VI model, which postulates a superadditive (but less than multiplicative) interaction between smoking and radon. To appreciate the magnitude of this interaction, consider the fact that the background lung cancer risk ratio between ever and never smokers is 13 to 1.⁶ A multiplicative interaction between radon and smoking would imply that, at the same level of radon exposure, the ratio of radon-induced excess risk between ever and never smokers would be the same as the ratio of background lung cancer risks between those 2 groups (i.e., 13 to 1). On the other hand, an additive relationship between radon and smoking would imply that radon would add the same extra risk to ever and never smokers exposed to the same dosage, making the excess risks ratio between the 2 groups equal 1 to 1. Using the BEIR VI model, the EPA calculates that, at a radon level of 4 pCi/L, the lifetime risk of radon-induced lung cancer death is 62 per 1000 for ever smokers and 7 per 1000 for never smokers, yielding an excess risk ratio of 8.86 to 1 between the 2 groups.¹ As 8.86 falls between 1 and 13, the BEIR VI model implies that radon adds more risk to ever smokers than to never smokers, but that excess risk is less than proportional to the lung cancer background risk of those 2 groups, suggesting a submultiplicative (but superadditive) relationship between smoking and radon. The BEIR VI model does not distinguish between current and former smokers.Given this implied superadditive interaction, the number of future radon deaths will heavily depend on population smoking rates. As smoking rates in the United States have been falling for several decades and are expected to continue declining, the overall magnitude of the radon death toll is likely to decline as well. The question we try to address is what is the magnitude of this expected decline?We extend the EPA''s analysis by examining the sensitivity of radon-related lung cancer in the United States to future smoking rates. We estimate the proportional decline in the number of lung cancer deaths caused by radon for the period 2006 through 2100, assuming a likely scenario for smoking rates. We do not forecast specific numbers of radon-induced lung cancer deaths because these numbers will depend on many factors likely to change over such a long period of time. Instead, we concentrate on the relative impact of the smoking decline on the overall radon death toll and also examine the benefits of remediating houses with high radon levels given the results of our analysis. Following the EPA''s approach, in our computations, we employ the BEIR VI model, thereby assuming a submultiplicative relationship between smoking and radon. In the remaining sections of the report, we discuss the assumptions, models, and data employed in our analysis, our findings, and the implications of the results for both the magnitude of radon-related risk to the population and the effectiveness of housing remediation in reducing such risk.     

Radon,Smoking, and Lung Cancer: The Need to Refocus Radon Control Policy

Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy.It is estimated that 222 520 new cases of lung cancer were diagnosed and approximately 157 300 people died from this disease in the United States in 2010.1 Exposure to radon—an odorless radioactive gas that can be trapped in homes and other structures—is considered the second leading cause of lung cancer after smoking.2–5 The Environmental Protection Agency (EPA) estimates that residential radon causes approximately 21 000 lung cancer deaths in the United States each year.6,7 In response, the EPA and numerous organizations, including the National Radon Safety Board, promote wide-scale radon screening and remediation in domestic residences.8The strong synergism between radon exposure and smoking as risk factors is a critical aspect of the relationship between radon and lung cancer.2,4,9 That is, the absolute magnitude of the lung cancer risk associated with radon exposure is significantly higher for ever-smokers than for never-smokers. It is estimated that 86% of radon-related lung cancer deaths are in current and former smokers.7,10Angell recently claimed that radon research and remediation programs have “stalled” in the face of severe funding cuts over the past decade and that there has been little progress in testing and remediation in the US housing stock.11 With the recent economic downturn and the resource constraints most governmental health departments face, Angell’s concerns unfortunately will remain salient in the near term. Thus, we have argued that a concentrated policy focus on smoking prevention and cessation and on smokers as targets of both smoking cessation efforts and of radon testing and remediation programs currently provides the most powerful and cost-effective opportunity for reducing the public health burden of radon.Although some researchers have made this argument in the past, there is very little evidence in the United States of any significant radon control activities targeting smokers or of any coordinated efforts between tobacco control and radon control programs or initiatives.4,12 We have elucidated the evidence-based position that residential radon control policy will be most effective and efficient if it combines forces with tobacco prevention and control efforts. We have also offered strategic guidance about what a synergistic radon and tobacco control approach entails.     

Current status of programmes to measure and reduce radon exposure in Irish workplaces.

National legislation, which implements European Council Directive 96/29/EURATOM in Ireland, sets a reference level of 400 Bq m(-3) averaged over any 3 month period for radon exposure in the workplace and also empowers the Radiological Protection Institute of Ireland to direct employers to have radon measurements carried out. This legislation came into effect in May 2000. Radon measurements have already been completed in show caves and other underground workplaces. Between 1998 and 2001, over 33 800 individual radon measurements were carried out in all ground floor offices and classrooms in 3444 schools nationwide as part of a programme undertaken jointly with the Department of Education and Science. Where the average indoor radon concentration in one or more rooms exceeded 200 Bq m(-3), remedial measures were implemented. For concentrations up to 400 Bq m(-3) this involved increased ventilation while for higher concentrations an active sump was normally installed. The results of the survey, as well as the effectiveness of the different remedial strategies, are discussed. In the case of other above ground workplaces, different approaches have been adopted. As a first step, workplaces in two known high radon areas were directed to have radon measurements carried out. This programme had limited success because of problems in obtaining accurate workplace databases and a general lack of awareness on the part of employers of the issues involved. From a sample of 2610 employers directed to measure radon, only 408 actually completed measurements and 37 workplaces were identified as having average 3 month average radon concentrations above 400 Bq m(-3). A total of 1356 employers ignored all correspondence, some of which was sent by registered post and signed for on receipt. Current initiatives are focused on the provision of information and include newspaper advertising as well as publications aimed specifically at both employer and employee representative groups. The ability to provide accurate information that encourages both measurement and remediation is seen as central to an effective radon workplace programme.     

Contaminated land liability issues: legal perspective.

Until recently, companies that contaminated land faced little prospect of being prosecuted or having claims made against them for any personal injuries or property damage arising from the contamination. Most companies would have considered it to be inconceivable that they could be required to clean up contamination resulting from an historic disposal, particularly if the disposal had been neither negligent nor unlawful. Current environmental law differs significantly, however, from the law which existed even 10 years ago. This paper examines liabilities arising from contaminated land. First, it discusses the new contaminated land regime and a parallel regime to remediate sites that are contaminated with radioactive substances. Second, it discusses remediation liabilities for water pollution. Such liabilities may well involve the remediation of contaminated land when groundwater is polluted. Finally, the paper examines liabilities for property damage and personal injuries arising from contamination by radioactive substances.     

U.S. women physicians’ residential radon testing practices

Introduction: These analyses were designed to elucidate U.S. physicians’ perception of residential radon risk, as measured by the prevalence of residential radon testing using a representative sample of U.S. women physicians from the Women Physicians’ Health Study database. In addition, characteristics of women physicians who were more likely to have conducted a residential radon test were identified.Methods: A random sample (n = 4,501 respondents) of U.S. women physicians aged 30 to 70 was obtained in the Women Physicians’ Health Study. Analyses were conducted using SUDAAN.Results: The overall prevalence of residential radon testing among respondents was 18%, 2- to 6-fold higher than any estimate of residential radon testing in the general population. The strongest relationship with radon testing observed through logistic regression was with marital status; age, ethnicity, and region of residence were also related.Conclusion: This study demonstrates that although U.S. women physicians are more likely to have conducted a personal residential radon test than the general population, 82% report not having done so. Increasing the awareness of physicians about the health risks associated with prolonged radon exposure will be essential if they are to play a role in addressing this important public health problem.     

Local health campaigns to reduce lung cancers induced by radon and smoking—Who responds?

The greatest risk factor for lung cancer is smoking, the second largest factor being raised radon levels at home. Initiatives to stop smoking and reduce domestic radon levels have met with some success, but in both cases a significant proportion of those affected have not taken action.The two risk factors combine, so that those who smoke and live in a house with high radon levels are at higher risk than if exposed to only one of the two threats. There is the potential for combined public health campaigns to better target those affected.Using postal questionnaires, we collected demographic information of those in Northamptonshire, UK, a radon Affected Area, who participated in Smoking Cessation Programmes, and compared these to a recent study by our group of those who had taken action to reduce radon. The comparison suggests that these two groups are significantly different, and in some cases differ from the general population. In addition, those who continue to quit smoking at 1 year were more likely to have children under 18 at home, and live with a parent or partner compared to those who had relapsed after the previous assessment at 4 weeks.There is merit in extending Smoking Cessation Programmes to include advice on reducing the risks from radon.     

The cost-effectiveness of radon-induced lung cancer prevention in schools

An economic evaluation of a radon-induced lung cancer prevention programme for schools in the United Kingdom is undertaken in this study, which presents a cost-effectiveness analysis with a generalisable model for estimating the cost-effectiveness of a radon remediation programme for schools from a societal perspective. It follows the guidelines for the methodological framework now considered appropriate in the economic evaluation of health interventions and employs best available national UK data and information from Northamptonshire on the costs and effectiveness of radon identification and remediation in schools, and the costs and health impact of lung cancer cases for all state schools in Northamptonshire between 1993 and 1997 (348 schools, including 170 adult staff and 1820 pupils). The resultant cost-effectiveness ratio was 7550 per life-year gained in 1997 UK pound sterling. Results from the sensitivity analysis show that the ratio is particularly sensitive to assumptions concerning two parameters: the average capital cost of remediation and discount rate applied to life years. This study highlights the need for the evaluation of other schools remediation-based radon-induced lung cancer prevention programmes in other countries using similar methodological techniques. Compared to other health interventions in the UK, the schools programme has a favourable ratio. When compared to other lung cancer prevention programmes available, however, the schools programme ratio is less favourable. Uncertainties remain around increased risks from childhood exposure to indoor radon.     

How to ensure that national radon survey results are useful for public health practice

Exposure to radon gas increases the risk of lung cancer. Preliminary national survey data collected by Health Canada indicate that approximately 10% of households exceed the recommended federal long-term guideline of 200 Bq/m3. However, results to date have been reported for large geographic areas in broad measurement categories. Given that Health Canada recommends the most rapid remediation for buildings with the highest concentrations, such reporting makes it challenging for public health authorities to target interventions to communities at the highest risk. Here we use data from a survey in British Columbia to illustrate how improved spatial resolution and more refined concentration categories would be valuable for prioritizing the use of limited public health resources. We encourage Health Canada in future to provide more specific, community-level information that can be used to inform local policy and to engage building owners in radon testing and remediation.     

Using the European Community Radon Software to estimate the individual health benefits of a domestic radon remediation programme.

Radon can be present in domestic properties at high enough levels to pose a health risk. Such levels can usually be reduced by simple means. Studies on a group of radon-remediated homes in Northamptonshire, a radon affected area, have estimated the health benefits and cost effectiveness from remediation and have shown that remediation can be justified. These assessments have been based on collective population-average risk coefficients. The advent of the European Community Radon Software (ECRS) permits the consideration of individual risk. In particular, it can take into account individual smoking habits, which significantly affect risk, as current scientific opinion is that risks from radon and smoking are multiplicative. This note indicates how the software can be used, and the usefulness of this approach.     

Domestic refrigerator air temperatures and the public's awareness of refrigerator use

This study chose 50 households in the Christchurch suburb of Papanui. The householders in this area represent a wide age and income range, there is a good mix of old and new housing stock, and most of the homes are owner/occupied with a small smattering of rental accommodation. Temperatures were obtained in the domestic refrigerators of these 50 households. Measurements revealed that the majority (60%) of the domestic refrigerators were not operating in the recommended 0-4 C temperature zone. The warmer temperatures found in the majority of the refrigerators in this study suggest that perishable foods are being microbiologically compromised. Food wastage and food borne illness may be the direct consequence of these unsafe food storage practices. The general knowledge of the householders as to the correct and safe storage temperatures for perishable foods in refrigeration appliance was poor. Eighty-eight (88%) of the householders did not know that temperature range their refrigerators should be operating within. Householders appear to have a high degree of understanding as to the need to cool foods down quickly and adequately before placing them in their refrigerators and to the need to store food correctly within their refrigerators to prevent cross contamination occurring. None of the refrigerators were fitted with a thermometer thus preventing householders from monitoring the internal temperatures in their refrigerators.     

A survey of householders' mitigation strategy: Response to raised radon levels

Background: Many Irish homes have unacceptable levels of radon,but there is no information on mitigation actions. Methods:All householders in an urban area with levels above 200 Bq/m³were surveyed and a 10% sample was interviewed; 141 of 233 (61%)responded. Results: Only 43% accurately recalled their radonlevel. Seventy-four percent sought advice, 9% consulted a mitigationprofessional and 6% completed home modification. Disincentivesto action were indecision (41%) and expense (29%). Average knowledgeof health risk was 9.48 of 12 items. Interviewees were concernedabout impact on house value. Conclusions: Support is requiredfor households with high radon levels to effect mitigation.     

Models for retrospective quantification of indoor radon exposure in case-control studies

In epidemiologic studies on lung cancer risk due to indoor radon the quantification of individual radon exposure over a long time period is one of the main issues. Therefore, radon measurements in one or more dwellings, which in total have been inhabited by the participants for a sufficient time-period, are necessary as well as consideration of changes of building characteristics and ventilation habits, which influence radon concentration. Given data on 1-y alpha-track measurements and personal information from 6,000 participants of case-control studies in West and East Germany, an improved method is developed to assess individual radon exposure histories. Times spent in different rooms of the dwelling, which are known from a personal questionnaire, are taken into account. The time spent outside the house (average fraction 45%) varies substantially among the participants. Therefore, assuming a substantially lower radon exposure outside the dwelling, the residence time constitutes an important aspect of total radon exposure. By means of an analysis of variance, important determinants of indoor radon are identified, namely constant conditions such as type of house (one family house or multiple dwelling), type of construction (half-timbered, massive construction, lightweight construction), year of construction, floor and type of basement, and changeable conditions such as heating system, window insulation, and airing habits. A correction of measurements in former dwellings by factors derived from the analysis is applied if current living conditions differ from those of the participants at the time when they were living in the particular dwellings. In rare cases the adjustment for changes leads to a correction of the measurements with a factor of about 1.4, but a reduction of 5% on average only. Exposure assessment can be improved by considering time at home and changes of building and ventilation conditions that affect radon concentration. The major concern that changes in ventilation habits and building conditions lead to substantial errors in exposure (and therefore risk) assessment cannot be confirmed in the data analyzed.     

Bringing health home: householder and provider perspectives on the healthy housing programme in Auckland, New Zealand

This paper describes the Healthy Housing Programme, an ongoing intervention initiated for New Zealand public housing tenants in 2000 and presents findings from an evaluation conducted over three consecutive years. The Programme aims to improve well-being by addressing the housing circumstances of families at high risk of infectious diseases, experiencing high levels of deprivation, and living in areas with high concentrations of low-income, and largely public, housing. This is achieved through improving the housing stock and better integrating housing, health and social services. The evaluation was based on Brinkerhoff's Success Case Methodology and sought to address the question: ‘how have providers and householders responded to an intervention that addresses the dynamism of the physical and social aspects of housing?’ Members of 30 households were interviewed, along with all available Programme providers (n = 19). Thematic analysis reveals that in the households evaluated the Programme promotes participation in housing decisions and, indirectly, neighbourhood life more generally. Benefits include a larger stock of social housing units appropriate to residents' needs, increased co-ordination between sectors and organisations, strengthened community networks through referrals to helping agencies, and heightened insight by government officials into the housing conditions of tenants. We argue that a programme originally seeking only to address specific health problems and risk factors has been strengthened as it has evolved to adopt a more holistic approach to promoting household well-being.     

The impact of who you know and where you live on opinions about AIDS and health care

We hypothesized that public attitudes towards AIDS and the safety of health care in the era of HIV would be more positive for people who knew someone with AIDS. We believed, moreover, that living in areas with high AIDS prevalence would result in more favorable attitudes. To test these hypotheses, we conducted telephone interviews with a random sample of 2000 U.S. adults (response rate = 75%) in summer 1988. Overall 19.5% of respondents said that they knew someone with AIDS or the AIDS virus. Thirteen percent of people who lived in low prevalences areas reported knowing someone with AIDS, compared with 27% of those in areas of high prevalence. Of the total sample, 38% reported knowing someone they believed was at risk. People who knew someone with AIDS were less likely to say they would change physicians or dentists if their provider was HIV infected or was known to be treating people who were infected. Knowing someone with AIDS was also associated with greater tolerance for those with AIDS to continue to work if they were able and with lower perception of risk of transmission in health care settings. Multivariate regression analyses indicated that personal contact was related to more positive attitudes. Counter to our hypothesis, living in a high prevalence area had no independent effect on attitudes. This surprising finding suggests that, after controlling for personal contact with someone with AIDS, where one lives does not influence attitudes. Because bringing people with AIDS into contact with others may have positive outcomes, we suggest implementation of interventions using this strategy.     

A cost-effectiveness analysis of domestic radon remediation in four primary care trusts located in Northamptonshire, UK

The paper considers how primary care trusts (PCTs), which are relatively new organisations in the UK health service, might respond to the health hazards associated with radon in domestic properties. To this end, the cost-effectiveness of radon remediation programmes in four primary care trusts is calculated and compared with those of other interventions that can avert and treat lung cancer. The results suggest remediation programmes in the primary care trusts are cost-effective on various criteria. Policy recommendations that follow for the primary care trusts include encouraging remediation among their populations and identifying those most at risk from radon's effects.     

Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. Ever use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.