Are regulators relying on inaccurate industrial air emission inventories? The long-held suspicion that estimated industrial air emission inventories for factories differ significantly from what is actually being released has been validated in a paper published in the Proceedings of the National Academy of Sciences (Vol. 94, June 1997, p. 6596). Regulators rely on estimated industrial emission rates, "which are often outdated, incomplete, or inaccurate," the researchers wrote. Emission inventories are the backbone of air pollution control strategies. Because it is costly and time consuming to gather air quality data from an outdoor monitor to determine what is being discharged, regulators require polluters to supply estimates of expected emissions. Businesses calculate their emissions on the basis of an EPA list of estimated emissions for sources ranging from small dry cleaners to petrochemical plants. Regulators use the inventories to determine an area's compliance with air quality standards and to develop controls for areas that do not meet the standards. The accuracy of these
inventories will assist states as they move to meet the new standards for ozone and particulate matter, EPA officials said. Regulators admit, however, that the accuracy of estimates varies. To help the Texas Natural Resources Conservation Commission pinpoint the sources of volatile organic compounds (VOCs) in
Estimated industrial air emission rates "are often outdated, incomplete, or inaccurate." —Ronald Henry, University of Southern California the heavily polluted Houston area, Ronald Henry, University of Southern California (USC), along with Clifford Spiegelman and EunSug Park, Texas A&M University, and John Collins, USC, compared ambient air quality data collected over a six-month period with an inventory of emissions
that had been reported by facility managers. The ambient data were collected by an automated gas chromatography monitor at a site run by the commission and located downwind from a large petrochemical complex near the Houston Ship Channel. The reported emission inventories were provided by the commission for all industrial sources of nitrogen oxides and organic gases in the Houston area. The reported inventories included the description, location, and emissions rates (in tons per year) of all individual sources in a company facility. The researchers collected ambient data hourly at part-perbillion levels on total nonmethane organic carbon and 54 VOCs. This information was then combined with data on wind direction and speed. Applying the multivariate receptor model, the team worked backward to identify a chemical profile that led to the pollution source. The inventory of industrial VOC emissions, as reported by several petrochemical facilities in the area, did not—except for one small source—reflect what is being emitted. The largest sources in the inventory did not even show up in the team's observed
USDA food survey finds many pesticides, few violations Although pesticide residues have been detected on 65% of fruits and vegetables sold in the United States, "dissipation of residues between farm and marketplace and standard food preparation techniques" cumulatively minimizes the risk to consumers, said the latest annual survey by the U.S. Department of Agriculture (USDA). The study analyzed fresh and processed samples collected in 1995. Despite the relatively high percentage of pesticide residues on fruits and vegetables, USDA said that just 3.8% appeared to violate EPA tolerance limits. About half the apparent violations were found on spinach. Of the total, 87.8% of the food samples were domestic. Even so, the number of probable tolerance violations cited in the 1995 survey was up from 1.3% in 1994 and 1.5% in 1993. USDA said it could not draw any conclusions, because year-to-year
variations in sampling techniques made comparisons impossible. The annual report is designed to help EPA's risk assessment process during the re-registration of pesticides. Jay Feldman of the National Coalition Against the Misuse of Pesticides said the findings were of concern because Congress adopted tougher pesticide standards when it passed the Food Quality Protection Act of 1996. The USDA study used earlier tolerance limits that critics have said do not account for the high fruit and vegetable intake and the higher susceptibility of children to pesticide exposures. The USDA also is researching consumption data to help EPA develop more protective tolerance levels. "The cumulative risk, the risk to children, is certainly much greater, simply because they were using outdated tolerances," Feldman said.
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All told, 7524 fruit, vegetable, and wheat samples were collected from 39 states and 17 foreign countries. A total of 69 pesticides—insecticides, fungicides, herbicides, and growth regulators—were detected on fresh, frozen, and processed fruits and vegetables. Postharvest applications—mainly preservatives, growth regulators, and fungicides—were responsible for 29% of the total detected. A total of 10 pesticides were detected on 79% of sampled wheat. The most common were two insecticides, malathion and chlorpyrifos methyl. Testers also found residues of the DDT metabolite DDE on 10% of the fruit and vegetable samples even though the compound has been banned in the United States since 1972. Copies of the annual report are available from USDA at (202) 720-5231. —RAE TYSON
data set, the paper said. The reported inventory of industrial emissions is "inaccurate in its location, composition, and emission rates of major sources," the researchers wrote. Jim Price, senior scientist in the commission's monitoring operations division, said he is unsure of Henry's conclusions. The discrepancy in data could be accounted for by several factors, including incorrect identification of the facility's longitude and latitude, a bias in the airflow, or inaccurate reporting of emissions by the company. But lead researcher Henry maintains that his team's analysis provides strong empirical evidence that regulators are making predictions based on inaccurate industrial emissions. "The system we are using now, developed 20-30 years ago, was created at a time when the sources of pollution were pretty obvious," Henry said. Now that most large sources of pollution are being controlled, fugitive emissions are an important source of toxics from leaking pipes and unreported handling practices. But measuring fugitive emissions—when faced with as many as 500,000 sources in a large petrochemical plant, for example—is quite expensive and would be hard to quantify. Henry recommended that regulators set up more monitors and that companies make observed monitoring a higher priority for their environmental departments. "People don't want to talk about the discrepancies," Henry said. Most regulators don't believe that the inventory discrepancies are large enough to warrant a wholesale overhaul of the estimated inventory system. Although agreeing that inaccuracies occur, Steve Bromberg, director of emissions monitoring and assessment in EPA's air office, noted that often the inventories do match the observed data. "We could be more certain of our emission inventories before we develop the control strategies, but that doesn't mean that we have a problem now," Bromberg said. He added that EPA is working to narrow the gap between observed and reported emissions. —CATHERINE M. COONEY
EUROPEAN
NEWS
Fertilizer taxes could play a valuable part in reducing nitrogen pollution in the European Union (EU) by reducing fertilizer use, an international team of researchers has suggested. Current policies are unlikely to achieve desired standards for nitrates in water, according to the report, which was sponsored by the European Commission's research directorate. The report reviews the impact of current agricultural and environmental policies on nitrate levels. It calculates that a 30% tax on manufactured fertilizers would reduce excess nitrogen in the Netherlands by 8% and a 100% tax would cut levels by 25%. Recent EU policies that could reduce nitrate levels are a 1991 directive designed to cut nitrate in water and a 1992 reform of the EU common agricultural policy that reduced prices for certain cereals and livestock and was expected to lead to less intensive agricultural production. The researchers concluded that the agricultural policy has had "little effect" on nitrogen levels. The Dutch government's decision to relax its strict contaminated land policy was praised by Dutch industry on July 2. The new approach abandons a requirement for contamination to be removed to the maximum extent and instead permits cleanup on the basis of suitability for use. The Dutch government announced June 19 that it was dropping its "multifunctionality" approach requiring all polluted land to be cleaned sufficiently to make it suitable for any future use, including housing development. The Confederation of Netherlands Industry and Employers welcomed the change as practical. Environmental groups have accused the government of undermining its commitment to sustainable development. Germany plans to quadruple funding for endocrine disrupter research, Environment Minister Angela Merkel announced July 3. The possible influence of certain chemicals on human and animal hormone systems "needs urgent clarification," Merkel said. Four chemicals suspected of having hormonal effects in humans and animals are at the center of the research program: tributyl tin, used as an antifouling agent in marine paints; bisphenol A, used in plastics production; alkylphenol ethoxylates, used in detergents; and phthalates, used to soften plastics. A draft European Union report on one suspected hormone disrupter, nonylphenol, already suggests that new regulations to reduce environmental exposure will be necessary, according to the German environment ministry. A proposal to collect and recycle all types of batteries by 2002 is moving forward within the European Commission. The commission's environment directorate, which has been considering an expansion of the 1991 batteries directive on the disposal of certain types of batteries, hopes to obtain formal approval for the proposal from the whole Commission before the end of the year. The proposal suggests that EU member states be required to introduce battery collection and recycling within two years of adoption of the amended directive, which could be as early as 2000. It also proposes phasing out cadmium use by 2008 and immediately banning the use of mercury. The latter is more of a formality because mercury in batteries was largely phased out by the 1991 directive. Limiting the sulfur content of fuel oils burned in power stations, refineries, and industry received a surprisingly positive hearing by EU national officials at a meeting in Brussels on July 3. The proposals were being discussed for the first time in a Council of Ministers working group. A draft directive published in March on the sulfur content of liquid fuels forms a central plank of a European Commission strategy to halve the area affected by acidification by 2010. There are currently no EU limits on the sulfur content of fuel oils. Some countries have average figures of 1% sulfur content or less; others have sulfur concentrations as high as 3.5%. The commission has proposed setting a 1% limit by 2000 for the EU.
—Reprinted with permission from ENDS Environment Daily, Europe's first daily environmental news service. Environmental Data Services, Ltd., London (http:llwww.ends.co.uk, e-mail
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