Radon poisoning, the second leading cause of lung cancer, was last decade's big scare. In recent years it has generally disappeared from the collective consciousness as people followed the advice of environmental experts and took steps to remove the cancer-causing threat from their homes and offices. Problem solved? Not quite. Because of the soil composition in parts of the capital, Jerusalemites are more at risk from the radioactive gas than the general Israeli population. Yet the odorless, tasteless, invisible and naturally occurring radioactive gas is a highly preventable health risk - for the educated and the aware. But corrupt contractors, corner-cutting radon testers, ineffective treatments and a set of well-intentioned government guidelines that leave significant loopholes are confounding the hazard. Radon is a gas produced by the decay of naturally occurring uranium in soil and water. The underlying chemical element of radium is found all over the world, but certain types of soil are more prone to radon. In Israel the most "radon prone" areas occur along the eastern line beginning in east Jerusalem and including Ma'aleh Adumim, Arad and Karmiel. Radon seeps into buildings from the soil, affecting mostly houses that have been dug into a mountainside. Any site that physically touches the earth or is below ground, such as a basement, is also highly susceptible to the carcinogen. Gerald Schroeder, head consultant for Rad-Safe, a commercial radon testing and consulting company, is particularly concerned about the dangers of radon in the extra bedrooms that homeowners add at the basement level. "Without exception, every place that I have tested which had been turned into a bedroom below grade had high radon levels," says Schroeder, who received his PhD from the Massachusetts Institute of Technology 35 years ago. His dissertation research focused on radon and he is the co-author of the only paper in the world analyzing the effects of radon on the moon. In general if a building has good ventilation, then the rooms and floors above the ground floor are not in jeopardy, he says. Still, extrapolating from the methodology derived by the US Environmental Protection Agency (EPA). which estimates that between 15,000 and 22,000 Americans die each year from radon complications, the number of deaths in Israel could reach upwards of 270 a year - and this is a conservative estimate. Radon is quantified in becquerel units which measure the amount of gas that disintegrates in one second in every cubic meter of air in the room. Under Israeli law, the legal amount of radon concentration allowed in any particular room is 200 Bq/m3. Schroeder, however, advises that radon levels should not reach over 80 Bq/m3. "I have seen how the permissible level has dropped over the years," he says. Based on recommendations by the Environment Ministry, the municipality currently obligates contractors to perform two levels of radon tests during the construction or renovation of a building. The first short-term test is administered under unnatural conditions and involves completely sealing the test room so that no one is allowed even to open a door to enter or exit and taking a radon measurement after a few days. The second long-term test is carried out after the building has been inhabited under normal "living" conditions in which windows and doors are left open and the test measures the radon levels over the course of a few weeks. Unlike the long-term test, the short-term test must be administered before contractors are allowed to acquire all the necessary permits for conclusion of a construction project. In theory, if the short-term test comes back with unacceptably high radon levels, the contractor must make the necessary adjustments within the building before performing the long-term test. The contractor, however, is under no legal obligation to inform the building owner of the results of the short-term test. In addition, nobody is held accountable to follow up and ensure that the long-term test is actually administered. Some new home owners are not even aware when they move into their new building that there was a problem with the original test or that they need to complete a long-term test. Thus, they are potentially exposed to needless radon hazards. Gil Reichmann, head of the municipality's environmental department, acknowledges the problem. The municipality, he says, has taken steps to rectify the loophole by requiring contractors to both sign a form stating that they intend to complete the long-term test and to deposit moneys that can only be reclaimed after completion of the test. For a contractor facing costly remedies to fix a radon leak in a new building in its final stages of construction, however, the loss of the deposit is hardly a motivating factor. Some contractors team up with the radon testers and intentionally cheat on the short-term test. Victor Steiner, director of natural ionizing radiation for the Environment Ministry, says that this type of cheating usually occurs when a contractor threatens to take his business elsewhere if the radon tester causes any "problems for him." But the municipality's Reichmann argues that, "You can look at the numbers and tell if something is wrong - if they are too low or even in the minus," he says, implying that the tester over ventilated the "sealed" room during the short test. Even when caught, however, the cheating testers face almost no lasting consequences. There are currently only 20 licensed radon testers in all of Israel. Last month the Environment Ministry tried unsuccessfully to revoke the license of at least one of the listed companies for the second time. It had tried, also unsuccessfully, to revoke the same license nearly five years ago. "Canceling a license is a difficult legal process," Steiner explains. "Usually, the tester will sue the Ministry of Environment and then the Israeli courts will rule in his favor under the law that says you cannot take away someone's living. So he keeps his job and stays on probation for a few years." Steiner assumed his current position in 1999, and, since that time, the ministry has never been able to cancel even one license. Legal difficulties aside, the ministry has tried to raise the standards for radon testers by requiring all the testers to take a new, eight-day course before earning certification. The improved regulations have lowered the cases of cheating, Reichmann says, but he concedes that someone intent on cheating the test will probably succeed. "We don't always know if the testers are being honest unless there is a complaint," he says. "We get a few complaints each month, but I'm sure they are committing more crimes than what reaches us." The process is hard to monitor because neither the municipality nor the Environment Ministry have control over the behavior of landlords or private building owners. Former Jerusalemite Yonaton Frimer recalls that he had lived in an apartment in Nahlaot that had been illegally divided into two apartments by a wall that blocked the natural ventilation of the apartments. When the testers showed up to conduct a long-term test, his landlord had the wall knocked down for the week of the test, and then rebuilt once the testers had left, thus skewing the results in his favor. In addition, if a private building owner decides not to correct a radon leak in his building then the municipality is powerless to force him to do so. And the process is costly. "Once, a person from a synagogue with high radon levels came to me and said they didn't have the money to correct the problem. Instead, they signed a paper saying that they acknowledged the risks," Reichmann recounts. The most effective way to prevent radon leaks is to attack the problem during the foundation-laying stage of a new building. Based on the Environment Ministry's recommendations, the municipality requires that underneath a building's foundation layer of concrete, builders must first lay down a level of gravel. Within the gravel, the contractor will place several pipes that will trap the radon and will also connect to vertical pipes leading towards the top of the roof. With the powers of vertical suction and physics at play, the radon will eventually be released through these pipes near the roof, thus circumventing the building altogether. Schroeder is skeptical of this method, noting that the pipes can become clogged from the gravel and the weather elements. Like moisture, radon enters the house through tiny cracks in the structure. "Radon, though much heavier, is much smaller than water, so if you have moisture problems, you should be concerned about radon problems," he emphasizes. Instead of using the pipe method, Schroeder recommends placing a strong tar-based sealant over the foundations, which will prevent radon from seeping up into the house. Schroeder has seen what can happen to owners who ignore warnings to take preventive measures against radon all too often. He recalls the story of two side-by-side, million-dollar villas located on the cusp of east Jerusalem. The owners decided to add basements. Based on his consultations, one of the owners decided to put down the sealant. A radon test later revealed that the house with the sealant had normal radon levels while its next door neighbor measured levels over 3,000 Bq/m3. Since the owners were loath to remove the "magnificent marble floor" that they had already laid down, they had to take what Schroeder calls "draconian methods" to remove the radon. The solution involved creating wells on either side of the house to be used with special air pumps that required huge expenses in their upkeep. Building engineer and contractor Timmy Lawson, who often deals with high-end construction projects, notes that most home owners do not have the means to install such elaborate solutions after the fact and can get be stuck with the initial poor workmanship even if the law is on their side. "Consumers need to be better informed because most people don't have the physical and mental strength to pursue a lawsuit against all the parties," he laments.