Denver meeting probes environmental conflicts - C&EN Global

Apr 5, 1993 - But making an effort at intelligent use and environmental soundness does not always mean that actions taken are without contention...
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FDA panel okays bovine growth hormone A long-controversial product—bovine growth hormone (BGH)—last week cleared the last major hurdle on its way to Food & Drug Administration clear­ ance for commercial marketing. The Veterinary Medicine Advisory Committee decided that use of Monsanto's BGH, sometribove, prepared by re­ combinant DNA methods, presents an // insignificant,, but "manageable" risk to human health. The committee, consist­ ing mostly of scientists from outside FDA, was convened by the agency to carry on what is regarded as the last ma­ jor evaluation of the company's BGH be­ fore FDA decides whether to approve its use nationwide. So far, BGH has been used only in re­ search trials on cows. It raises milk pro­ duction about 16%, but it also increases the incidence of udder infections (masti­ tis). According to data FDA presented to the committee, the average incidence of mastitis in control cows is 36 cases per 100 cows. In BGH-treated cows, it is 54 cases per 100. When these figures are ad­ justed for greater milk production, the value would be 15 additional cases of mastitis per 100 cows over a normal pe­ riod of lactation. Although the percent increase is sub­ stantial, FDA considers it negligible in comparison to the seasonal variation in mastitis incidence. Rates of mastitis can vary as much as 200% from winter to summer. Increased mastitis is to be ex­ pected in all high-milk-producing cows, according to Monsanto spokesman Tho­ mas McDermott. The panel found a slight risk to hu­ mans from use of the growth hormone. It comes not from BGH residues, which are not biologically active in humans, but from the possibility that residues from the antibiotics used to treat the ex­ tra cases of mastitis would end up in the milk supply. As has been the case since FDA first started looking at the BGH issue more than a decade ago, many controversies swirl around it. Those who believe the milk supply is adequately tested by the states and by FDA claim the extra antibi­ otic used to treat additional cases of mastitis will pose no problems. This po­ sition is shared by Monsanto and FDA. By contrast, the General Accounting

Office (GAO), which did a report on FDA's testing of milk in 1990 and found many problems, says, "Current with­ drawal and withholding requirements [for milk] may well be inadequate to deal with such [antibiotic] concentra­ tions." In March, Eleanor Chelimsky, as­ sistant comptroller general at GAO, said in a letter to Donna E. Shalala, Secretary of the Department of Health & Human Services, that FDA should conduct anti­ biotic assays of milk from treated and control cows to measure the extent of the antibiotic residue problem. So far this has not been done. Michael K. Hansen, research associate at the Consumer Policy Institute, the re­ search arm of Consumers Union, says that comparing the 50% increase in mastitis rates to the seasonal variation in mastitis is "a very peculiar interpretation of 'safe/ " It is analogous to arguing that if a drug causes ear infections in children as a side effect, but the rate of increase is no greater than the seasonal variation in ear infec­ tions, the drug is safe, he explains. "We cannot see how FDA can say a drug that causes disease is safe," he says.

Last week, Sen. Russell D. Feingold (D.-Wis.) introduced legislation to re­ quire mandatory labeling of dairy products from BGH-treated cows. Most observers predict that if labeling is re­ quired, the product will not be used. Sixty dairy and grocery companies and all three major infant formula pro­ ducers oppose approval of BGH, and have pledged not to accept milk from BGH-treated cows. Groups represent­ ing individual dairy farmers, such as the National Farmers Union and Na­ tional Family Farms Coalition, also are campaigning to stop BGH approval. However, the large dairy producer as­ sociations, such as the National Milk Producers Association and the Interna­ tional Dairy Food Association, favor the action. Eli Lilly, American Cyanamid, and Upjohn also are developing BGH prod­ ucts. Business Week estimates a total worldwide market of about $400 mil­ lion. BGH is expected to be the first multi-million-dollar agricultural prod­ uct produced by genetic engineering. Bette Hileman

From Denver

Denver meeting probes environmental conflicts Controversies in several environmental areas were spotlighted at the American Chemical Society's national meeting in Denver last week. Sessions focused on debates surrounding obligatory use of oxygenated fuels in automobiles, effects on agriculture of a possible ban on methyl bromide, and potential health β 5" | S

Romer: use energy intelligently

hazards of exposure to electromagnetic fields. Colorado is a particularly apt setting for such discussions. The first state to order use of oxygenated fuels in wmtertime, Colorado is seeking "to develop and use energy intelligently and with environmental soundness/' said Gov. Roy R. Romer in opening a keynote session addressing energy and the environment in the 21st century, organized by the Division of Environmental Chemistry. But making an effort at intelligent use and environmental soundness does not always mean that actions taken are without contention. Oxygenated fuels are a case in point. According to Larry G. Anderson and colleagues at the University of Colorado, Denver, the mandated use of oxygenated fuels to diminish carbon monoxide levels has had no statistically significant effect on atmospheric carbon monoxide con­ centrations in the Denver area, and actu­ ally may have increased levels of other pollutants such as formaldehyde. Car­ bon monoxide levels have been dropping since 1981, but that decline, AnderAPRIL 5,1993 C&EN

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NEWS OF THE WEEK son maintains, is due to fleet turnover as old cars are taken out of service. In studies elsewhere, oxyfuels also have been found to elevate organic carbonyl compounds in the atmosphere. Data collected in the Albuquerque, N.M., area suggest organic acids, especially formic acid, have increased in the atmosphere there as a result of oxyfuel use. And complaints by residents of Fairbanks, Alaska, concerned about health problems associated with the use of oxyfuels, led to a petition to the Environmental Protection Agency to waive the oxygenated fuel requirement there. Another ACS meeting symposium, sponsored by the Division of Agrochemicals, focused on controversy surrounding the soil fumigant methyl bromide. Like chlorofluorocarbons, methyl bromide can deplete stratospheric ozone. EPA has proposed it be classified as a Class 1 ozone-depleting substance under the Clean Air Act, which would result in a ban on its use by 2000. Methyl bromide is used widely to sterilize soil before planting, to fumigate commodities after harvest, and to control structural termites. California, which employs more fumigants than any other state, used 8 million kg of methyl bromide in 1988, notes Lisa Ross of the state's Department of Pesticide Regulation. Nancy N. Ragsdale, of the Department of Agriculture's National Agricultural Pesticide Impact Assessment Program (NAPIAP), told the symposium that actions to ban or restrict methyl bromide use would be costly. Currently available alternative pest control practices are less effective or more expensive. NAPIAP estimates that annual U.S. economic losses from a methyl bromide ban would be $1 billion to $1.2 billion. The impact in California could be devastating, adds Michael V. McKenry, a nematologist with the Kearney Agricultural Center at the University of California, Riverside. McKenry, who has studied methyl bromide use as a soil fumigant for 20 years, says a proposed excise tax in 1994 that will triple the cost of methyl bromide is likely to hasten the compound's demise. Unlike in the other 49 states, no substitute for methyl bromide is registered in California. "We've taken the last true soil fumigant, and one of the preferred commodity fumigants, and in a year will make it unavailable for all practical purposes," McKenry says. 'If s going to be an enormous change for growers." 6

APRIL 5,1993 C&EN

There are also large economic stakes hanging on the outcome of studies dealing with health effects from exposure to electromagnetic fields. At another Division of Environmental Chemistry symposium, biophysicist Charles N. Rafferty, manager in the environmental division at the Electric Power Research Institute, Palo Alto, Calif., noted that, worldwide, $32 million was spent researching the issue last year, $21 million in the U.S. But this expenditure is trivial, he says, compared with what it would cost society for delays in power line siting and construction, redesign of appliances and power lines to reduce field levels, possible property value losses, and litigation. "Epidemiology studies have driven the research for 15 years," and their results have focused on cancer effects, Rafferty says. Recent studies in Sweden have found statistically significant risks for leukemia in children and adults, leading to a conclusion that the relative risk increases with level of exposure.

One current hypothesis on how electromagnetic fields might cause cancer is that exposure decreases production of melatonin, a hormone produced by the pineal gland. And that decrease may be what brings about cancer, directly or indirectly. Biochemist Larry E. Anderson, bioelectromagnetic program manager at Battelle Pacific Northwest Laboratories, Richland, Wash., notes that a decrease in melatonin is associated with a decrease in immune response and an increase in growth of cancer cells. Cautioning that there is currently much confusion over the biological effects of electromagnetic fields, Anderson nevertheless cites animal studies that implicate the fields as affecting melatonin production or increasing the risk of cancer. Both Rafferty and Anderson say future studies should find ways to establish whether electromagnetic fields actually alter melatonin levels, and what melatonin's role is in the cancer process. James Krieger, Deborah Illman, Mairin Brennan, Rudy Baum

From Denver

ACS unveils two new information services Two new information services were unveiled by the American Chemical Society in Denver last week. Both are designed to help subscribers keep pace with research and events in the chemical world. One initiative, called Advance ACS Abstracts, is intended to give chemistry professionals an easy, affordable way to keep up with basic and applied research published in ACS journals. The service will provide the author with abstracts of papers accepted for publication in all 22 ACS journals, along with the tentative scheduled dates of publication of the complete papers. The second initiative will make available full-text Chemical & Engineering News articles through STN International, the worldwide computer network providing on-line scientific and technical information. This venture, called C&EN Online, starts later this month. Subscribers to Advance ACS Abstracts will receive abstracts of 500 to 600 articles to be published in ACS journals within two to eight weeks. The periodical will premier in July 1993, and will be issued 24 times a year. The subscription price for ACS members is $40 a year, and for nonmembers $260. Until

July 1, charter subscribers can get 26 issues for the price of 24. A joint effort by ACS's Publications and Chemical Abstracts Service divisions, Advance ACS Abstracts is expected to publish some 12,500 abstracts annually. It also will be available on-line at the same time as the published version, as part of the CA Previews file distributed by CAS on STN International. "It's impractical for individual chemists to subscribe to or read all of the ACS journals," explains Charles R. Bertsch, head of the ACS Journals Department. "For one low price, Advance ACS Abstracts lets them scan every abstract we publish." C&EN Online already has a database containing some 8000 articles from 1991 to the present, and will be updated weekly to add all of the articles in each new C&EN edition. It is planned to have C&EN articles from current editions available on-line each week by Monday, the date of issue of the print edition. The database is searchable for any word or phrase, or by title or author. The articles on-line contain text only, and do not include illustrations. James Krieger