Environmental tobacco smoke revisited: the reliability of the data used for risk assessment.
Nilsson R.Department of Genetic and Cellular Toxicology, Stockholm University, Sweden. robertn@kemi.se
Several epidemiological studies have found a weak, but consistent association between lung cancer in nonsmokers and exposure to environmental tobacco smoke (ETS). In addition, a purported link between such exposure and coronary heart disease (CHD) has been of major concern. Although it is biologically plausible that ETS has a contributory role in the induction of lung cancer in nonsmoking individuals, dose-response extrapolation-supported by the more solid database for active smokers-gives an additional risk for lung cancer risk that is more than one order of magnitude lower than that indicated by major positive epidemiological studies. The discrepancy between available epidemiological data and dosimetric estimates seems, to a major part, to reflect certain systematic biases in the former that are difficult to control by statistical analysis when dealing with risks of such low magnitudes. These include, most importantly, misclassification of smoking status, followed by inappropriate selection of controls, as well as certain confounding factors mainly related to lifestyle, and possibly also hereditary disposition. A significant part of an association between lung cancer and exposure to ETS would disappear, if, on the average, 1 patient out of 20 nonsmoking cases had failed to tell the interviewer that he had, in fact, recently stopped smoking. In the large International Agency for Research on Cancer (IARC) multicenter study even lower misclassification rates would abolish the weak, statistically nonsignificant associations that were found. In the former study an apparent significant protective effect from exposure to ETS in childhood with respect to lung cancer later in life was reported, a most surprising finding. The fact that the mutation spectrum of the p53 tumor suppressor gene in lung tumors of ETS-exposed nonsmokers generally differs from that found in tumors of active smokers lends additional support to the notion that the majority of tumors found in ETS-exposed nonsmokers have nothing to do with tobacco smoke. The one-sided preoccupation with ETS as a causative factor of lung cancer in nonsmokers may seriously hinder the elucidation of the multifactorial etiology of these tumors. Due to the high prevalence of cardiovascular disease in the population, even a modest causal association with ETS would, if valid, constitute a serious public health problem. By pooling data from 20 published studies on ETS and heart disease, some of which reported higher risks than is known to be caused by active smoking, a statistically significant association with spousal smoking is obtained. However, in most of these studies, many of the most common confounding risk factors were ignored and there appears to be insufficient evidence to support an association between exposure to ETS and CHD. Further, it seems highly improbable that exposure to a concentration of tobacco smoke at a level that is generally much less than 1% of that inhaled by a smoker could result in an excess risk for CHD that-as has been claimed-is some 30% to 50% of that found in active smokers. There are certainly valid reasons to limit exposure to ETS as well as to other air pollutants in places such as offices and homes in order to improve indoor air quality. This goal can be achieved, however, without the introduction of an extremist legislation based on a negligible risk of lung cancer as well as an unsupported and highly hypothetical risk for CHD.
Publication Types:
Evaluation Studies, Review, Review Tutorial
MeSH Terms:
Cardiovascular Diseases/etiology; Humans; Lung Neoplasms/etiology; Myocardial Ischemia/etiology; Risk Assessment/standards; Tobacco Smoke Pollution/adverse effects*
PMID: 11726024 [PubMed - indexed for MEDLINE]
La. getting less money from tobacco settlement than projected
August 11, 2005
BATON ROUGE, La. With the number of smokers decreasing nationwide and the market share of certain tobacco companies declining, Louisiana has received 60 (m) million dollars less than expected so far from its annual payments as part of the national tobacco settlement.
State Treasurer John Kennedy says that indicates Louisiana followed the right path in selling off sixty percent of the state's share of the tobacco settlement early, for part of its projected worth.
And state officials are starting to consider whether they should sell the remaining forty percent _ a move that would end Louisiana's link to the fate of the tobacco companies but could give the state less cash than it might receive through annual payments.
A panel will start the initial discussion of the prospect at a meeting next week.
Louisiana is one of forty-six states that settled lawsuits with tobacco companies in 1998 in return for installments of money. The 206-(b)-billion-dollar settlement requires cigarette companies to make the payments as reimbursement for health care costs related to tobacco use.
http://www.katc.com/Global/story.asp?S=3683954
Heading down a new tobacco road
By Arthur Hirsch Sun Staff Originally published July 29, 2005
A University of Maryland research project seeks to juice up the familiar plant and develop it as a source of proteins for numerous uses by other industries
UPPER MARLBORO - The tobacco thriving here on the University of Maryland's research farm looks like the plant that dominated state agriculture for centuries, the leaves mint green, fuzzy to the touch, long and wide as the blades of a ceiling fan.
These plants have been to college, though, and might be nearing the threshold of a future that generations of tobacco farmers would scarcely recognize.
For one thing, this vision of Maryland tobacco's future is stamped "NO SMOKING." Think, instead, of tobacco as a component of cosmetics, diet supplements, medicine or shampoo. Consider high-protein fluids for kidney dialysis patients, and drugs that might someday be used to treat, of all things, cancer and heart disease.
It all seems at least as unlikely as the idea that Maryland tobacco has a future at all. Growing on a testing ground here no bigger than a Major League Baseball diamond, this tobacco might help resurrect a Maryland business shrunk to a fragment of its old self since the 1980s, most recently by a program that has paid farmers millions to stop growing tobacco for smoking.
Since the buyouts, a question has been hanging in the air, said Gary V. Hodge, a Southern Maryland regional planner who helped run the tobacco program that began in 1998, cutting Maryland tobacco sales from 9.58 million pounds to 1.4 million this year.
"Now what?" Hodge said. "We're trying to answer that question."
He was standing under a hazy sky on the test patch off Route 202 recently with a group of men involved in the University of Maryland's Alternative Uses of Tobacco Project. These men have doctoral degrees and business experience. They are schooled less in the arduous work of bringing tobacco to local auctions year after year than in chemical extraction technology and multibillion-dollar markets in pharmaceuticals.
The future of Maryland tobacco and the state's agricultural landscape might lie there.
Because along with the aroma, taste and nicotine buzz smokers crave, tobacco offers proteins. Extracted in pure form, the protein might compete with milk, egg and soy proteins used in sundry ways by industry.
The hope, said Hodge, is to restore the economic impact of Maryland tobacco, which in 1997 accounted for two-thirds of Southern Maryland's farm income while growing on less than 5 percent of farmland in those five counties.
Neil A. Belson, president of Pharmacognetics Inc., a biotechnology company in Port Tobacco and a member of the project team, called the effort part of a larger shift from petroleum-based to plant-based industrial materials, "from a hydrocarbon to a carbohydrate economy."
All plants produce proteins and other compounds, but the reason scientists are so enthusiastic about tobacco in particular is evident even to the untrained observer visiting the research farm. In a word: volume.
"Bulk is a key appeal of tobacco," Belson said.
The plants can be grown in dense thickets, sprouting leaves nearly as long as your arm and a couple hands across. Crop science people call all this green stuff "biomass," and tobacco produces more of it per acre than any other crop.
That matters when the compounds you're trying to extract constitute very small percentages of the whole plant. The more mass you start with, the more of any given material you might get.
This means treating Maryland tobacco in a new and rather brutal way. For much of its centuries-long history, the plant has been babied step by step.
The Maryland tobacco farmer typically transplants about 6,000 seedlings per acre in spring and harvests once in late summer. The stalks are raised in roomy rows, chopped by hand and hung in barns to air dry through the fall and winter, the dried reddish-brown leaves then carefully stripped off by hand, tied in fan-like clusters and bundled off to market in spring. Maryland tobacco farmers could hardly take more care if they were raising orchids.
Tobacco's steady decline here beginning in the 1980s had much to do with the difficulty of finding labor to raise it. The Alternative Uses project suggests a new, mechanized and high-volume tobacco crop that would demand less labor.
The researchers have devised direct seeding methods to raise about 90,000 plants per acre, harvesting two or three times a year. Leaves harvested by machine on the research farm recently have been trucked to the University of Maryland's College Park campus and unloaded at the old creamery, where the school once made ice cream.
Lately, professors and graduate students working there have run a few tests on a noisy configuration of conveyors, hammer choppers and a screw press, cutting about 200 pounds of tobacco leaves into particles as fine as "McCormick spices," said Y. Martin Lo, an associate professor in the University of Maryland's Department of Nutrition and Food Science.
Some of the juice has been taken to a laboratory and run through an elaborate series of spinnings, filtrations, washings, chemical treatments and cooling to produce a pure protein crystal: colorless, odorless, tasteless.
Lo said they have produced maybe a couple teaspoons of two different proteins. It's a small start at a stage of the game where quantity matters if you are trying to attract investors.
Crop scientist Ray Long knows that only too well from his research at North Carolina State University in Raleigh, where work on protein extraction and bio-engineered tobacco began in the 1970s.
Long ruefully recalled a day in the 1990s when a representative of a chemical company that supplies the cosmetics industry called him asking about tobacco protein.
"He said they would like to have 50 pounds to do formulations and test in a market," Long said. "I didn't have 50 grams. ... That has been the Catch-22."
That is, the research on how to produce large amounts of this pure protein costs money, which might be available from industry representatives if they could get large amounts of the material.
The difficulty of inducing the plant to produce significant amounts of a particular protein by genetic manipulation should "not be trivialized," said Long's N.C. State colleague, Arthur Weissinger. He estimates it could be 20 years before human vaccines based on tobacco proteins will be produced.
The Maryland research, which does not include genetic engineering, anticipates results sooner.
By the end of 2006, Lo wrote in an e-mail, researchers hope to have a blueprint for a protein-producing operation. Such a design on paper would then be offered "to interested parties such as tobacco farmers or investors to establish a commercial processing facility adjacent to tobacco farmlands," Lo said.
Researchers here hope to attract investors while there are farmers around who know how to grow tobacco, and before too much more farmland is transformed into subdivisions and shopping centers.
More than 80 percent of Maryland tobacco farmers took the buyout, meaning they agree never to grow tobacco again for smoking and what the state calls "similar personal consumption."
That would not include sipping a soft drink that has been given a nutritional boost with a shot of tobacco protein, or foaming up your hair with a tobacco-protein shampoo, washing out the smell of a night in some smoky bar.
Smoking Referendum to be Proposed
NBC 15 Updated: 6:15 PM Aug 15, 2005
Video:Smoking Ban Referendum?
Some of Madison's alders want the public to decide on the city's smoking ban this spring. On April 4th residents would be able to vote on an advisory referendum.
Alders acknowledge that some businesses need immediate help because sales are down, and they claim it is due to the smoking ban.
That's why alders want to give those bars and restaurants an exemption to the law, but only if their profits show more than a 10 percent decrease over a three month period.
"I get 40 e–mails a day plus phone calls on this issue,” says District 13 Alder Isadore Knox, Jr. “I think what we are trying to do is do the reasonable thing in terms of looking at the impact it is having on businesses, and certainly trying to respect the wishes of people that do not smoke."
Mayor Dave Cieslewicz thinks otherwise.
"He is not supporting the referendum,” says Cieslewicz spokesman George Twigg. “Because he feels that leaders are elected to lead, and this is a decision that the mayor and the city council should make, and if voters disagree they can replace them at the polls."
While those are the Mayor's thoughts on the referendum, he says he would consider a hardship exemption, but it would have to meet certain criteria.
The alders plan to present their proposal at the city council's September 6th meeting.
http://nbc15.madison.com/news/headlines/1683691.html