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• ! [ THE WALL STREET JOURNAL. Cancer Scare How Sand on a Beach Came to Be Defined As Human Carcinogen Tests Using Common Silica Spark a Scientific Clash Over Safety, Procedures Sounding Grass-Roots Alarm By DAVID STIPP Staff Hepar[er of TnF. W ALL aTREET JaVRX/A. After Jim Swide recently emptied abag of sand into his two-year-old daughter's sandbox, some words caught his eye: "may contain ... crystalline silica ... known to the state of California to cause cancer." Horrified, the resident of Ukiah, in northern California, snatched his daughter out af the playare&. "I thought,'Whyam I letting my daughter play in something th&t says right on the label, It causes canceRa !' be says. "It was quite a shock." Mr. Swtde scooped up the sand, returned It to the store and got his money back. Richard Shoemaker, the store's owner, hadn't noticed the warning, but now posts it prominently. After all, he notes, it looks like the stuff on a California beach. In fact, it is. Crystalline silica, the primary ingredi- ent of sand and rocks, looms asperhaps the scariest cancer demon ever. It is in count- less products: pharmaceuticals, bricks, paper, jewelry, putty, paint, plastics, household cleansers - notto mention bags of sand for toddlers' backyard boxes. Finding It Everywhere Soil is laced with the stuff, so is dust In the air. Most water supplies are filtered through sand, so it Is in drinking water. Traces of it cling to root vegetables and other foods. Silica, formed when silicon and oxygen chemically combine, makes up about a quarter of the Earth's crust. (Some silica is in a noncrystailine, "anwrphous" form that isn'f linked with cancer.) The idea that much of the planet's surface is a deadly chemical may sound like the stuff pf science fiction. But, it is true: For several years, crystalline silica has been classified as carcinogenic by various regulatory agencies, including the federal Occupational Safety and Health Administration. The official lumping of beach sand in the same category as carcinogens such as dioxin, critics contend, suggests as noth- ing before that the regulatory system tends to cry wolf when it comes to cancer. It underscores broader concerns among scientists that the tradttionat method of massvely dosing rats to assess caticer risk- coupled with regulatory tripwires set to go off at the slightest hint of carcino- genic potential-is fundamentally Bawed. Indeed, most researchers agree there is no clear-cut evidence that silica is carcino- genic fnhumansn even at high doses over many years, much less at levels most people are exposed to. Emphasizing the lack of compelling data, former govern- ment researchers, in an extraordinary dispute, maintain that a federal report linkingsilica to cancer was published after earlier versions of the same report-which showed little evidence of the link - were discarded for no good scientific reason. Legal Lhpflcations "Silica is not something Mr. and Mrs. America should be worrying about," says Joseph Mcfaughlin, a National Cancer Institute researcher and co-author of a comprehensive study on the issue. The government's labeling of silica as - carcinogenic "has opened up huge legal implications," adds Malcolm Ross, a sci- entist with the U.S. Geological Survey. ^Products are liable to be dropped, or people will be scared to use them." In Wisconsin, the widow of a former quarryworker is seeking compensation for his lung cancer, alleging it was caused by silica. California agencies have pressured companies that emit silica to Inform coh- sumers about im cancer risk - thus, the warning on sand. Now grass-roots gtoups are sounding the alarm, and officials In Industries that use silica fret theymay face a flap like the asbestos scare of the 1980s- - an episode, according to many experts, that wasted billions of dollars and need. lesslyendangeredthousandsofpeopleisee article on page AS). Citing Dust "Crystaliine silica is as dangerous or more dangerous than asbestos," declares_ Alma Schreiber, a Fetton, Calif., resident seeking limits on dust emissions by a local ~ quarry. She adds that she first heard the substance Is carcinogenic from PacificGas ~&®ectric Co., which, In compliance with California's "t'ight-to-know" law un haz- ardous substances, warned Its customers ' that it sometimes conducts sandblashng, which emits crystalline silica. The utility says California knows the chemical causes cancer. How did California cnme to know more than scientists on this issue? Crystalline silica's reputation began __ _ with the discovery in the 1500s. that heavy dust exposure among miners can cause _ lung disease. Researchers now call it silb _ cosis-a noncancerous, fibrous scarring of the lungs following prolonged, heavy expa sure to silica-laden dust. The disease now rarely occurs berause of regulations limiting dust exposure In the workplace. But doctors have seen thousands of cases of silicosis through the years. Yet they haven't noticed abnor mally high cancer rates among patients - exposed to silica dust. In 1982 one re- - searcher wrote that "the incidence of lung P(ease 7trrn to Page A8, Gblumn f

• How Sand on a Beach Was Defined ~ ~~ Cancer Scare. As a Human Carcinogen and Sparked a Controversy 0 • • Contitiued Proyn FFrst Page cancer in miners with silicosis is signifi- cantiy lower than in non-silicotic males." But that year, a graduate student at the University of North Carolina, David Gold- smith, made a splash by proposing that silica can cause cancer. Several clues suggested that conclusion, says Dr. Gold- smith, now at the Western Consortium for. Public Health, Berkeley, Calif. In particu- lar, Laurence Holland, a researcher at Los Alamos National Laboratory in New Mex- ico, had just reported that when high doses of silica in water were repeatedly injected into the lungs of 36 rats, six developed tumors. That "struck me as quite power- ful," says Dr. Goldsmith. Dr. Goldsmith, the most ardent advo- cate of the view that silica poses a cancer risk, in 1984 organized a conference, "Sil- ica, Silicosis and Cancer." Soon after, an arm of the World Health Organization, the International Agency for Research on Can- cer, formed a"working group" of scien- tists to look at the issue. After examining past studies, the group found "sufficient" evidence that silica is carcinogenic in animals, but only "lim- ited" evidence that it is in humans. Still, in 1987, the agency listed silica as a "proba- ble" human carcinogen - a label it affixes when at least two animal studies indicate a substance causes cancer. 'Plausible and Prudent' According to a policy statement, this automatic leap from limited animal data to a declaration of human risk is "plausible and prudent" to flag cancer risks early. But many scientists find it troubling. Among other things, the policy gives little or no weight to studies indicating that substances don't cause cancer. The listing of silica as a probable human carcinogen was based chiefly on five rat experiments. But at least five similar studies in ham- sters and mice, all reported by 1986, found no evidence of cancer. Moreover, even the rat studies weren't very compelling, according to scientists who conducted them. Most of these re- searchers blasted the rats with silica doses 100 or more times the amount humans are exposed to, even in the dustiest work- places. Most tumors that developed were different from those that typically occur in cases of human lung cancer, notes Los Alamos Laboratory's Dr. Holland. Despite conducting the pivotal rat study that Dr. Goldsmith cites as "power- ful," Dr. Holland concluded in a 1990 review of cancer-silica studies that "there is a great deal of uncertainty" about silica's link with cancer and decried "re- peated overreaction to every positive ex- perimental observation." • Adds Corbett McDonald, a professor at Montreal's McGill University and chair- man of the international working group on silica: "There was sufficient evidence in animals and limited evidence in man"' of rcinogenicity. "But [the agency] has his custom of saying'probable.' It doesn't mean that it is probable. And then the U.S. agencies tend to take the next automatic step of treating it as a carcinogenic sub- stance. That's the trouble." Indeed, OSHA's cancer alarm goes off more readily than the international agency's - the Labor Department agency requires just one study indicating a sub- stance is carcinogenic to trigger its cancer- warning rules. Thus, the international body's classification of silica as a probable carcinogen automatically activated OSHA's "hazard communication stan- dard," requiring companies to issue warn- ings to employees about workplace materi- als containing more than 0.1% of crystal- line silica. Intentionally Broad Despite the skepticism among many scientists, OSHA says it did the right thing. Its rules on toxic substances are intention- ally broad to ensure that employees know about dangerous substances. But consider what happened on Thanksgiving Day 1990, when firefighters arrived at a blaze at a pottery plant in Roseville, Ohio. The fire started as workers burned empty bags of sand used for glazes. The bags had been tagged as containing carci- nogenic crystalline silica. Rock Samson, Roseville's fire chief at the time, says that when his men first arrived and started dousing the flames, "I thought it was going to be simple.... But then I got to seeing the warnings on some of the bags. When I saw that I said, 'Okay boys, it's time to get out of here.' " The firefighters pulled back, cordoned off a "hazardous materials hot zone" and called for help, says Mr. Samson. Soon, a small army of firefighters from four towns brought in nine trucks and assorted equip- ment, including a "deluge gun" for spew- ing water from a distance at hazardous materials. Emergency workers rushed house-to-house to warn residents to stay inside with doors and windows closed lest they breathe toxic fumes. When the blaze was finally extin- guished, Mr. Samson and his firefighters checked into a hospital. "We got chest X-rays and the whole nine yards," he says. "It was just a precautionary measure. But I've had a couple of close brushes with death, and it makes you think what could happen to you." As silica scares multiply, a crisis at- mosphere is mounting in industry circles. Officials with the Chemical Manufacturers Association, the National Industrial'Sand Association and other groups say their main concern is liability lawsuits. "Suppose a consumer sees a cancer warning on abag of crushed limestone Ire's put on his driveway, later develops lung cancer and then sues the limestone pro- ducer," frets Frederick Renninger, a spokesman for the National Stone Associa- tion, a trade group in Washington, D.C. He adds that the fine points of the scientific debate are likely to get lost in such emo- tionally charged cases - just as they did in the scare about Alar, the apple growth regulator that was banned by the Environ- mental Protection Agency even though limited rat data indicated the chemical posed little, if any, risk. But Dr. Goldsmith still contends low exposure to silica outside dusty workplaces may increase a person's risk for lung cancer. "The evidence is that silica is a probable carcinogen," he asserts. "That doesn't mean ambient exposure will result in lung cancer. But at the same time, it doesn't mean you're safe." Few silica experts agree with Dr. Gold- smith's opinion that ambient silica- meaning levels outside mines or other dusty workplaces - is worth worrying about. But Dr. Goldsmith's view may carry the day: The EPA, as a prelude to possible action aimed at limiting public exposure to silica, is relying on him as its main_ consultant on silica-and-cancer data. Dr. Goldsmith says he recently scanned human studies on the issue and found that 24 of 26 studies showed a statistically significant inereased-risk of lung cancer among workers exposed to silica. But at least six prior reviews by other research- ers concluded that the jury is still out. Many studies Dr. Goldsmith has cited as suggesting an increased risk don't account for smoking among the workers. Blue-collar workers have a higher smoking rate than the general population, which may explain higher lung-cancer risks in miners and quarry workers. Indeed, in one study on silica exposures among Vermont granite-quarry workers who had an elevated lung-cancer rate, researchers obtained smoking histories on 84 of the workers who died of the disease. AB 84 were smokers. Moreover, many of the studies were based on company records of workers who received disability compensation for lung disease. Past studies show such employees tend to minimize how much they smoke. That can produce what seems to be a high lung-cancer rate among those ex- posed to silica dust, even when smoking records are factored in. Skeptics also note that few studies linking silica with lung cancer have ac- counted for other, well-established carcin- ogens - including arsenic dust and radon found in mines. To be sure, there are a few studies that, after accounting for smoking and other factors, suggest silica exposure raises the risk of lung cancer. But other, equally rigorous studies have found no signs of cancer risk from silica. WAIL SfiREff XRNAL.. 31 ~;t.1 ~1 3

THE WALL STREET JOIJRNAL. • • . In one of the most thorough studies, reported last year in the British Journal of Industrial Medicine, a team led by Dr. McLaughlin of the cancer institute care- fully sorted out possible causes of 316 cases of lung cancer among 1,668 miners and other "dusty trades" workers in China. Tungsten miners with heavy silica expo- sures, they found, actually had about half the risk of lung cancer as the general population. In contrast, silica-exposed tin miners had elevated lung cancer rates- but they also were exposed to significant amounts of arsenic dust. "The study doesn't really provide support for a causal relationship between silica and lung can- cer," concludes Dr. McLaughlin. Link to Lung Cancer Against this backdrop of uncertainty, a controversy recently erupted over a report by the National Institute for Occupational Safety and Health on the silica question. After more than a decade of analysis of health records on 3,246 quarry and mine workers, NIOSH last July reported that the data indicate exposure to silica is associ- ated with lung cancer. Industry officials that supplied the worker records for the study say the institute - which conducts research on OSHA Issues-molde4 the report to reach a politically correct, preordained conclu- sion. They note thatin four earlier drafts of the report, no significant silica-cancer link was found. Former NIOSH employees who helped shape the earlierversions are critical. One of them, Robert Reger, now a professor at West Virginia University and a consultant to the National Stone Association, calls the final report a"disaster;" He faults its authors for conGuding, silica was associ- ated with increased lungcancer risk in granite workers even though data on their smoking rate wasn't available. . Gregory Wagner, a NIOSH manager who oversaw the final report, counters that the previous analyses that didn't find a significant cancer link were "cronfusing" and "lacked clarity. Ultimately, I said [to the NIOSH researchers involved], 'Go back to the beginning and tinker with it.' " The final report, he insists, was "dear, accu- rate and scientifically credible" and con- tains appropriate caveats. Dr. Wagner adds that the granite workers with a high rate of lung cancer probably smoked at about the same rate as the general population because their rate of other smoking-related diseases, such as heart disease, wasn't elevated. Thus, smoking probably didn't account for their high cancer rate. But other researchers say manual workers who smoke often have relatively low heart-disease rates-constant exercise offsets their smoking-related heart risk. Moreover, in one early version of the NIOSH report, researchers noted that when they obtained smoking histories for 30 workers who died of lung cancer-589o of the total who died of the disease - they found 93% had been smokers. That infor- mation was dropped from the final re- port, along with the earlier conclusion that the excess lung cancer cases in the workers "can be largely attributed to cigarette smoking." While controversial, the study is likely to carry much weight in the silica debate. "Things that get disseminated by the U.S. government sometimes have a way of becoming sacrosanct," says Dr. Reger. Indeed; Ukiah's Mr. Swide is still wor- ried after learning that the government- designated carcinogen he exposed his daughter to was ordinary sand from Cali- fornia's Monterey beach. "It was just an unnecessary risk to have that stuff around," he says.