Lung Cancers among Non-smoking Occupants

Air Chek, Inc. is performing survey of over 16,000 households that have tested for radon gas. Rather than attempt to conduct a complete epidemiologic study, the intention is to demonstrate a method of locating lung cancer victims within neighborhoods based on the likelihood that the majority of the structures will have radon measurement levels within a similar range. A preliminary survey was mailed to computer-selected addresses asking specific health and exposure questions. The initial results indicate there may be some correlation of lung cancer occurrences in residences with elevated radon levels. This paper will provide an overview of the survey method, results and data evaluation. INTRODUCTION Most radon-related health studies have been criticized because of their very limited residential measurement data. With this in mind. Air Chek, Inc. decided to initiate a preliminary study of our data base of addresses that have been tested for radon. The objective was to fmd a better method of locating lung cancer victims who have, for an extended period of time, occupied structures with related levels of radon gas. This study is still in its initial stages: however, it has already generated information worthy of reporting. METHODOLOGY The initial survey group was chosen from the Air Chek data base consisting of over one million radon test results. Our first experiment involved mailing a one-page questionnaire to 5000 computer-selected addresses to test the return rate. These were sent to 170 different zip codes having the highest measurements. First we requested that recipients not respond unless the tested structure was at least 15 years old. Then they were asked to mark, with a circle, the correct answers to a few simple questions. Next they were asked to refold the page in reverse order to reveal a prepaid return address and then drop it in a mail box. The goal was to make responding as simple as possible. Once the requested information was obtained from this group, Air Chek sent follow-up questionnaires to respondents who indicated a lung cancer victim had occupied the tested structure for 15 years or more. The replies to this second mailing are still coming in. For the next mailing similar surveys were mailed to each group listed below, based on an algorithm which selected zip codes with 20 or more measurements with the majority (approximately 90% of the measurements) falling within the desired range. The algorithm was designed to increase the likelihood that exposures at places outside the home (e.g., in the office or school) might be within the same range. Bear in mind, although not used in this study, in some zip codes areas we have the option of factoring in hundreds of test results made during large-scale school testing programs. Over 250,000 classrooms have been tested using our samplers. Group 1: 3,436 surveys were mailed to addresses with measurements less than 4 pCi/L, inside of zip codes where most of the measurements were also less than 4 pCi/L. 1995 International Radon Symposium 1 4.1 Group 2: 4,079 surveys were mailed to addresses with measurements ranging from 4 to 10 pCi/L, inside of zip codes where most of the measurements ranged from 4 to 10 pCi/L. Group 3: 2,012 surveys were mailed to addresses with measurements ranging from 10 to 10 pCi/L, inside of zip codes where most of the measurements ranged from 10 to 20 pCi/L. Group 4: 6,914 surveys were mailed to addresses that measured over 20 pCi/L. Within this group each zip code had to have a total of 10 or more structures with measurements exceeding 20 pCi/L. but not necessarily having a majority of them over 20 pCi/L. This modification was necessary because there are fewer zip codes that have 90% of their results above 20 pCi/L. A total of 16,441 survey forms asking health, occupancy, structural and lifestyle questions were mailed to these groups. The First question asked the individual not to respond unless they were acquainted with someone who had occupied the premises for 15 years or more. We asked for the age of structure, whether any occupant had ever smoked, and if yes, for how long? One question asked if any occupant had ever been diagnosed with cancer and if so what type. It also asked the sex of the victim, age when diagnosed, years of occupancy and occupation.