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Spray Technology & Marketing Although the production and consumption of CFCs HCFCs and Halons was minimal in the USA during 1993, in other parts of the world substantial usage still continues. Organizations such as the United Nations Environmental Program (UNEP) and most national environmental agencies or ministries are working hard to bring about further reductions. Of the approximately 140 countries that signed the Montreal Protocol of 1987 and later accords, about 30 were considered "developed," based upon their use of at least 0.4 kg/yr per capita of CFCs. The other 110 or so were earlier called Third world", but now "developing" or "Article 5" countries. Since these developing countries include the P.R. of China, India, Malaysia, Indonesia and many in Africa, it is not surprising to note that they contain over 75% or the world's population and thus have the potential to use prodigious amounts of chemicals and commodities. Many "Article 5" countries have no CFC or HCFC production base, and their governments may not have the infrastructure to determine import quantities. Consequently, only about 16 of these countries normally report their production and consumption figures. Their latest figures included comparisons of 1989 to 1992, and showed that their consumption of CFCs increased by 45%. Even more dismaying to ecologists is that consumption of carbon tetrachloride (a CFC precursor) was up by 332%. This nonflammable compound is at least 10% stronger than CFC-11 and CFC-12 as a stratospheric ozone depleter. As might be expected from countries with such diverse populations, economies and policies, the data was very erratic. In the P.R. of China-population 1.19 billion- production of CFCs was up by 116% from 1989 through 1992. Production of HCFCs was up modestly, and Halon manufacture was down by 2%. Production of CFCs has since increased even more, since a new plant has now come on line. In Argentina, CFC production has dropped by 70%. Even in the "developed" countries, large amounts of CFCs are still being produced little for aerosols but mainly for refrigeration, air-conditioning, foam blowing and solvent uses. The data reported by 16 of these countries showed a reduction of production and consumption of about 56% for CFCs and 51% for Halons in the 1989-1992 period. The latest figures suggest production of about 420,000 tones (or 924,000,000 pounds) of all CFCs. Actually, 12 more "developed" countries were asked to report and failed to do so. Thus, the above figures must be regarded as somewhat less than the total. The "developed" countries also reported sales of 22,866 tones (50,300,000 pounds) of CFC-11 and CFC-12 for aerosols in 1992-down 91% from ten years earlier. The U.S.A. figure is estimated as 8,400 tones for aerosols in 1992, with almost half of this allocated for metered dose inhalants (MDIs), and the rest for other medical uses plus very limited military and essential product applications. As much as 500 tones (1,100,000 pounds) of CFC-114 is thought to be used in USA medical sprays. The production and consumption of CFCs in the USA and other developed countries has been made subject to the Montreal Protocol and its various amendments, through Meetings Two through Five of the Parties-unless further restricted by individual governments. For CFCs, production in 1994 can be no more than 25% of the 1989 baseline, and in 1996 it will cease altogether. The effect of this phaseout on the medical aerosol industry is hard to judge at this moment, because of the complex interplays of regulations, patents, toxicological test requirements, propellant availability and so forth. Halon production and sales were terminated at the beginning of 1994, although some 133,000 tones (292,000,000 pounds) are banked in tanks and equipment worldwide, and some of this will become available for reuse. The phaseout of HCFCs is rather complex. The Montreal Protocol requires that, as of 1996, consumption by "developed" countries must not exceed 103.1% of the 1989 level. This will decrease to 65% of that level by January 1,2004, and continue downward in stages until extinction on January 1,2030. In the USA the aerosol uses of the HCFCs have become extremely limited, since most of the previous exemptions were eliminated on January 17, 1994. The transition from such propellants as HCFC-22 has become somewhat less onerous for the aerosol industry, since HFC-134a is now available as a nonflammable replacement-although at four times the cost. As potential stratospheric ozone depleters, HFC-152a, HFC-134a, HFC-227ca and other CFCs are now reported to be some 50,000 times less potent than the CFCs, according to a recent study conducted by the National Oceanic and Atmospheric Administration (NOAA). The agency began these studies in 1993, because of a concern raised by some atmospheric scientists that fluorine from actinically disintegrated HFCs might react with trace amounts of carbon in the stratosphere. The environmental concern regarding HFC-134a relates to its global warming capability. The atmospheric lifetime of the gas is about 15.4 years. If the total warming effect of an HFC-134a release is integrated over a 100 year time frame and compared with that of carbon dioxide (the standard), it is found to be about 1200 times as potent. This data is often reduced to the statement that the GWP for HFC-134a is 1200 (compared to CO2 =1). It's interesting to apply a little mathematics to all this. The weight of the earth's atmosphere is 7.7 x 1015 tons (3.5 x 1015 metric tones). The percentage of CO2 is currently about 0.0375%, making the CO2 global atmospheric inventory about 2.9 x 1012 tons (1.31 x 1012 metric tones). Let us model an aerosol industry use of 10,000,000 lbs. (4.54 x 103 metric tones) per year. Multiplying by 1200 gives us the CO2 equivalent: 12,000,000,000 lbs. or 5.45 x 106 metric tones. This is the equivalent of adding: 5.45x106 x 100% = 4.16 x 10-4% Scientists have stated that a doubling of the current CO2 inventory would add about 7.0 to 11.2°F (4.4 to 6.3°C) when a new climatic equilibrium is finally established, over a century later. If we take the average of 9.1°F (5.0°C) and see what effect the emission of 10,000,000 lbs. of HFC-134a The current position of HFC-134a suppliers is to sell HFC-134a for aerosol applications where there are industrial and medical concerns regarding flammability. These applications had already been identified by regulators when they were dealing with the CFC and HCFC situations. Then there is a less well-defined area of consumer products, where flammability is a major problem, either from government regulations or from consumer misuse experience. In the case of large volume household or personal products-such as those where the non-VOC characteristic of HFC-134a might solve a state regulatory limitation-the producers will not supply HFC-134a. However, HFC-152a is almost always useful in solving VOC related problems. STATUS OF THE OZONE LAYER In 1993, the Journal of Geophysical Research reported the change in average ozone amount (m. atm.cm.) across most of the earth's surface (70°S. to 70°N.) over the years 1978-1992, with an extrapolation of the straight line until 1995. The inventory sank from 309 to 288, with the extrapolated value given as 282. The averaged reduction over the last 17 years is thus 8.75%. A UNEP/IE/PAC report, dated July 1994, places the cumulative ozone depletion over the entire earth as about 13.7% since 1972. The amount of ozone over specific areas has decreased by very different degrees since mid-1977, according to the World Health Organization (WHO). The so-called "ozone hole" is media hyperbole for a temporary thinning of the ozone layer over Antarctica- and now, since about 1992, for a much smaller thinning over the North Pole. The Antarctic "hole" has occurred each Southern Hemisphere spring since the mid-1980s, when it was discovered and verified. The maximum occurs in early October, when the ozone concentration averages 90 Dobson Units instead of the usual 250 Dobson Units- a 64% reduction. On September 27, 1992, it reached a record 9.4 million square miles, but measured 9.0 million square miles in late 1993. For comparison, the continental USA (48 states) measures 3.609 million square miles. One of the more-or-less forgotten aspects of the CFCs is that they are profound global warming agents, and even now are said to comprise about 20% of the annual increase in global warming. Since the CFCs have atmospheric lifetimes of about 100 years, and since it takes the average CFC molecule (released at the surface of the earth) about 9 to 12 years to reach the stratospheric ozone layer, we are currently seeing ozone reductions that represent the CFC inventory situation of about 1984. A vast amount of CFC has been produced and emitted to the atmosphere since then, and more will be made in the near-term future. The reduction in the use of CFCs for European aerosols has fallen by over 90% since about 1990, if Russia is excluded. However, the CFCs are still produced there and used for refrigeration, air-conditioning and other applications. Many of these are where the CFC is tightly contained in a system, and may not be taken out of that system for many years. Regulations differ as to the fate of the CFCs, once they are removed and replaced with (for instance) HFC134a. In Sweden, they are collected and incinerated. In Greece they will be simply discharged into the atmosphere. Measurements of the growth rate of CFC concentrations in the atmosphere over Europe give an idea of the effect of the multinational efforts to curb emissions. For CFC-11 the annual growth rate fell from 11 ppt-v (1985-88 base years) to 3 ppt-v in 1993. Similarly, CFC-12 fell from 20 to 11 ppt-v. These decreases represent about a 60% average reduction in consumption, with some countries achieving a reduction of 80 to 82%. Most experts feel confident that the atmospheric concentrations of CFCs will continue to rise until the years 2000 to 2005. The Halon and CFC phaseout schedule visualized by the United Nations Environmental Program (UNEP) is that the non-Article 5 (developed) countries (Group 1, Annex B) will produce and consume no Halons after January 1,1994,25% of the 1989 base year production of CFCs after January 1, 1995, and no CFCs after January 1, 1996. An exception is made in that the developed countries may produce, for export to satisfy the basic domestic needs of Article 5 (developing) countries, up to 10% of their 1986 levels of CFCs and up to 15% of their 1986 levels of Halons, after January 1, 1994. (And 15% of the CFC level after January 1, 1996.) This could change during the ten year grace period given to the Article 5 countries to stop using CFCs by 2006. Production facilities in the developed countries cannot efficiently run at 10 to 15% of capacity, and the ire of government officials and environmentalists for those firms that continue to produce would be overwhelming. Perhaps more importantly, plants for the production of CFCs and Halons exist in some of the Article 5 countries-and are continuing to be built (China) that will be sufficient to serve the needs of all these countries. As a note, DuPont has stated that they will cease CFC production, worldwide, by January 1, 1996. Given this background, UNEP may well cancel the export allowances of the preceding paragraph. In fact, at the Fifth Meeting of the Parties" (Bangkok, November 17-19,1993) representatives of 122 nations agreed that there was no necessity for an export exemption in the production of Halons in 1994 or later. The situation of P.R. of China is relatively unique, since it is by far the largest of the Article 5 countries in terms of population (1.19 billion), and CFC usage. Jessica Poppele (The World Bank), in an article in The China Business Review a few months ago, stated that China currently consumes 132,000,000 Ibs. (60,000 tones) of CFCs and Halons. Their use is expected to grow at about 11% per year, as their economy continues to rapidly expand, and consumption should reach about 260,000,000 Ibs. (118,000 tones) by the year 2000. China is poised to become the largest global consumer of ozone depleting substances (ODS) by as soon as 1996. The country has stated that with financial support from the international community, it hopes to eliminate its consumption of ozone depleting substances by about the year 2010-four years after the end of the grace period. However, they indicate a need for $1.4 billion to get the job done. The countries (Parties) in the Montreal Protocol approved the Executive Committee's proposal for a three-year Multilateral Fund budget of $510 million at their meeting a year ago. These funds are allocated toward assisting firms that wish to change from CFC type operations to alternative formats. Under the Fund Secretariat, four organizations can act to administer fund appropriations: UNEP (IE/PAC), UNDP, UNIDO and the World Bank. To a significant degree, approvals are made based upon the amount of CFC (or Halon) reductions obtainable, in tones/year. In the case of the Chinese aerosol industry, two examples of support grants can be mentioned. The Tianjin First Daily Use Chemical Factory was awarded $2.77 million to establish a facility to purify the local (very high unsaturate odor) hydrocarbon propellants so they can be used for hair sprays and so forth in the firm's aerosol filling plant. The grant will also be used, in part, to build a gassing center, where all the standard safety equipment is utilized. The Shanghai Ja Le Aerosol Factory received $2.31 million to do essentially the same purification and gas-house programs just described. The fact that Chinese gas-well propane and butanes typically run from 3 to 7% of various unsaturates, has posed a major problem for the country's aerosol fillers. With molecular sieve techniques, unsaturates [such as butene-2, CH3-CH=CH-CH3, and isobutylene, (CH3)2C=CH2] can be removed, but not economically in such large amounts. The dual installation of a molecular sieve and hydrogenation unit would work, but seems well beyond the indicated level of World Bank funding. An interesting and difficult problem in China is that of the "cottage industry," where a group of family members and perhaps some friends will gather together once every few evenings to produce anywhere from 500 to 2000 aerosols in the house, barn or workshop. The CFCs that they use are purchased in large cylinders from nearby refrigeration barn or workshop. The CFCs that they use are purchased in large cylinders from nearby refrigeration supply stores. There are at least 500 such "firms" in P.R. of China-and perhaps twice that number, since most are rather clandestine-plus hundreds in India, and a hundred or more in Indonesia/Malaysia. When the aerosols are paper labeled and boxed, the men of the family will take them away in pushcarts bicycle "trailers" or trucks, to be sold in the nearby villages and towns. Obviously, the transition away from CFCs will put all these people out of business, but that is not projected to happen soon. Since it first approved funding for CFC and Halon phase out activities in P.R. of China (February 1992) the Multilateral Fund has spent about $25 million. About 46% has gone into the foam industry. At least 25 current projects are in various stages of completion, but only two or three involve aerosols. The largest aerosol project relates to the Aestar Fine Chemical Inc. Ltd. firm in Zhongshan (Guang Dong Province) in southern China. To give an idea of the size of this bastion of aerosol and liquid production, the plant is 970,000 ft.2 (80,000 m2), with an R&D area of an added 115,000 ft.2 (9,500 m2), on a plot of ground roughly 1,950 x 1,950 ft.2 (300,000 m2). They employ over 3,000 people. The plant also produces their own requirements of tinplate and aluminum aerosol cans, Coster-type valves, plastic caps, and even deodorizes raw kerosenes by molecular sieve techniques. On their property is the very new, 16-story National Aerosol Technology Development Center, owned and operated jointly by Aestar and the government. Considering the $1.4 billion in conversion resources needed by P.R. of China, and the relatively small size of the Multilateral Fund ($100 million per year) ,which must be distributed not only to P.R. of China, but to numerous other countries as well, it becomes problematical that this huge country can eliminate CFC and Halon consumption by the year 2010. However, authorities there are very responsive to environmental concerns, and no doubt will act in various ways to encourage the transition away from ozone depleters to more rational approaches. While the goal of total elimination may not be reached by the year 2010, certainly major strides toward that final expurgation will have been taken by then. One of the most difficult problems in the elimination of CFCs has been their replacement in aerosol medical inhalants. Based on an estimated worldwide use of about 15,500,000 lbs. (7,000 tones) per year in 1994-projected to rise by about 6% per year to about 21,700,000 lbs. (10,000 tones) per year by the end of 1999-this area has received an enormous amount of technical attention. Ultimately, the CFC11, CFC-12 and (sometimes) CFC-114 now used in these products will be replaced by HFC-134a (mainly), with HFC-227ca, and small amounts of certain solvents to enable solubilization of the excipient substance...but without solubilizing or enabling Ostwald ripening of the micronized drug substance. Under the auspices of the International Pharmaceutical Aerosol Consortium for Toxicity Testing (IPACT), and other consortia, the basic toxicology of the new HFCs has been (or is still being-in some cases) suitably defined. The program for HFC-134a was completed in mid-1994. That for HFC-227ca will be done in early 1995. Those for low pressure replacements may be done about the end of 1995. Concurrently, formulation development has occurred, with just about all replacement formulas now completed. Formulation and component toxicity testing was generally finished during 1994, allowing INDs to be filed, so that clinical trials could begin. These are now on-going. "Easy" formulations may finish this phase by mid-1995, while the more incalcitrant ones could take until mid-1997. NDAs (New Drug Applications) will mostly be filed with the US FDA from mid-1995 to mid1997, at which time marketers will have to wait about two years for the wheels of bureaucracy to grind away. Assuming, very optimistically, that there are no safety problems, non-CFC medical inhalant launches could begin by mid-1997 for easy formulations and by mid-1999 for the more obdurate ones. The question of CFC supply during the period of January 1, 1996 to the launching of the new, HFC-based products becomes more controversial with each passing day. One interim possibility is to use recycled CFCs, since no more will be produced. The aspect of clean-up must then be addressed along with the validation of whatever firm might undertake this operation. Currently, assessors and U.S. Pharmacopoeia monographs presume that all medical inhaler ingredients are virginal-unless specifically identified otherwise. Thus, if a marketer wished to use recycled propellant, approval would have to be obtained. An official variance would have to be sought, and that might not be easy. Another approach is that of stockpiling. A tankcar of CFC- 12/11 blend, for example, would contain possibly 125,000 Ibs. (56,800 kg). If we postulate a use level of 15 g per inhalant, then the tank car would be sufficient to produce 3,800,000 units-discounting manufacturing and heel losses. This approach would produce mixed emotions in Washington, D.C., since virgin material is subject to a huge disincentive tax, whereas recycled material presumably would not. As a final comment, the onus of the CFCs still lies heavily upon the aerosol industry, even though they were virtually eliminated from our products in 1978. The average consumer still believes that aerosols are implemented in atmospheric problems of some kind, and memories are often jogged if CFCs or the ozone "hole" are mentioned. The industry's public relations program, with the central theme that aerosols are free of CFCs has performed miracles with the relatively limited funds available, and millions of school children and adults alike are now aware of the true facts of the matter: that nearly all aerosols are CFC-free, except a few vital medical and industrial products.
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