Heat treated หรือ Methyl Bromideเลือกแบบไหนดี? 1- HT and MB process.
Heat Treatment (HT) : Wood packaging material should be heated in a schedule that achieves a minimum core temperature of 56ºC for 30 minutes. บรรจุภัณฑ์ไม้จะถูกอบโดยใช้ความร้อนให้มีอุณหภูมิ ณ แกนกลางไม้ไม่น้อยกว่า56 องศาเซลเซียส เป็นเวลาไม่น้อยกว่า30นาที
Methyl Bromide (MB) Fumigation : Wood packaging material should be fumigated with Methyl Bromide. บรรจุภัณฑ์ไม้จะต้องผ่านการรมด้วยเมทิล โบรไมด์
To learn more about Methyl Bromide
2- Advantage & Disadvantage.
Here are the comparision for HT vs MB
Heat Treatment (HT)
Advantage :
1- HT is 100% safe to human and environment because no chemical is used in the process.ปลอดภัยต่อมนุษย์และสิ่งแวดล้อม100% เนื่องจากเป็นวิธีที่ไม่มีการใช้สารเคมีใดๆในกระบวนการ
2- HT will last long life of wood packaging materials.วิธีนี้จะเป็นการทำทรีตเมนต์อย่างถาวรตลอดอายุของบรรจุภัณฑ์
3- HT is easier to monitor and control the process.ง่ายกว่าในแง่ของการควบคุมและดูแล
4- Because HT is 100% safe, HT is widely being used for food and agriculture products.เนื่องจากเหตุผลในข้อ1-จึงเป็นวิธีที่ใช้ในสินค้าประเภทอาหารและสินค้าเกษตรอย่างกว้างขวาง
Disadvantage :
1- The cost of HT is significantly higher than MB ,especially for investment.ต้นทุนของHTสูงกว่ามากในแง่ของการลงทุนเกี่ยวกับเครื่องมือและเครื่องจักร
2- HT need some quantity of cargo to be treated , difficult to treat in small quantity. ปริมาณของบรรจุภัณฑ์ต้องมีมากพอเพื่อทำไม่ให้มีต้นทุนที่สูงเกินไป
3- Normally, HT process take longer period of time.โดยปกติวิธีHTจะใช้ระยะเวลาที่นานกว่า
Methyl Bromide (MB)
Advantage :
1- The cost of MB is significantky lower than HT, small factory can afford for the investment. ต้นทุนของMBต่ำกว่ามากโดยส่วนใหญ่ผู้ผลิตบรรจุภัณฑ์รายย่อยจะนิยมใช้วิธีนี้ เนื่องจากการลงทุนต่ำกว่าHTมาก
2- MB is easier to work with small quantity of cargo. สะดวกกว่าในกรณีที่เป็นจำนวนน้อยๆ
3- MB process take shorter time. ใช้เวลาที่สั้นกว่า
4- MB can penetrate or diffuse into the cargo, but not food or consumer products.วิธีนี้ สารเคมีจะมีการแพร่กระจายไปในสินค้าที่ใช้บรรจุภัณฑ์นั้นๆด้วย
Disadvantage :
1- MB have a certain limit of life time , it will dilude after the process finished. เนื่องจากเป็นการรมด้วยสารเคมี จึงมีอายุการใชังานที่จำกัด เนื่องจากสารเคมีจะค่อยๆจางลงหลังกระบวนการสิ้นสุด
2- MB is a chemical gas that is colourless and cannot smell , but very dangerous to human and living thing. เนื่องจากสารMBไม่มีสีและกลิ่นอีกทั้งเป็นอันตรายต่อผู้สัมผัสและผู้ใช้ การใช้สารชนิดนี้อาจถือได้ว่าเป็นการเสี่ยงอันตราย
3- MB is now Banned or phased out in developed country and strictly prohibited to use in food and agriculture products. สารMBได้ถูกแบนและลดการใช้ลงเรื่อยๆในเหล่าประเทศที่พัตนาแล้ว
4- The use of MB is affecting the ozone in the atmosphere, many country will reduce and find other alternative . การใช้สารMBส่งผลต่อโอโซนในชั้นบรรยากาศ หลายประเทศจึงพยายามลดการใช้และหาทางเลือกอื่นทดแทน
FAQ - Frequently Answered Questions about Methyl Bromide
What is methyl bromide? How is it used?
- Why has EPA taken action on a pesticide under the Clean Air Act?
- When will methyl bromide be banned?
- Are there alternatives to methyl bromide?
- What about the science linking methyl bromide to ozone depletion?
- What is the Montreal Protocol? How does it regulate methyl bromide?
- More Questions - Latest Rumors and Innuendoes.
- How can I get more information? Other Methyl Bromide-related Web Sites
- What is methyl bromide? How is it used?
Methyl bromide is a broad spectrum pesticide used in the control of pest insects, nematodes, weeds, pathogens, and rodents. In the U.S., about 21,000 tons (42,000,000 pounds) of methyl bromide are used annually in agriculture, primarily for soil fumigation (85%), as well as for commodity and quarantine treatment (10%), and structural fumigation (5%). Globally, about 72,000 tons (143,000,000 pounds) are used each year, with North American use the highest (38%), followed by Europe (28%), Asia (22% - includes Israel and the Mid-East), with South America and Africa combined using the least (12%). For additional methyl bromide use information, click here.
The chemical name (IUPAC, CAS) for methyl bromide is bromomethane, and it is classified as a alkyl bromide. It is a colorless and odorless gas at normal temperatures and pressures, but the liquified gas can be handled as a liquid (14.4 lb/gal) under moderate pressure. The specific gravity at 0บC and 760 mm Hg is 1.732, with a vapor density of ~3.27, boiling point of 3.6บC (38.5บF), vapor pressure at 20บC of 1400 mm/Hg (at 40บC it is 2600 mm/Hg), and the viscosity is 0.22 centistokes at 0บC. Methyl bromide is readily soluble in lower alcohols, ethers, esters, ketones, halogenated hydrocarbons, aromatic hydrocarbons, and carbon disulfide.
The vast majority of this chemical is manufactured by three companies: two located in the U.S. state of Arkansas (Great Lakes Chemical and Ethyl/Albemarle), and one in Israel (Dead Sea Bromine). These companies utilize naturally occurring bromide salts which are either contained in underground brine deposits (as is the case with Arkansas), or in highly concentrated above ground sources like the Dead Sea. Ocean water does contain bromine salts, but at such low concentrations that it is very energy intensive to use as a source in the manufacture of methyl bromide. Methyl bromide is often produced as a by-product of other bromide manufacturing processes.
When used as a soil fumigant, methyl bromide gas is usually injected into the soil at a depth of 12 to 24 inches before a crop is planted. This will effectively sterilize the soil, killing the vast majority of soil organisms. Immediately after the methyl bromide is injected, the soil is covered with plastic tarps, which slow the movement of methyl bromide from the soil to the atmosphere. Additional methyl bromide is emitted to the atmosphere at the end of the fumigation when the tarps are removed. When an entire field is fumigated, the tarps are removed 24 to 72 hours later, as can be the case in strawberry production in California. However, with row (or bed) fumigation, as is the case with tomato production in Florida, the traps are left on for the entire growing season, some 60 to 120 days. About 50 to 95% of the methyl bromide injected in to the soil can eventually enter the atmosphere. In the United States, strawberries (18% of U.S. total) and tomatoes (23% of U.S. total) are the crops which use the most methyl bromide, consuming about 7,000 tons (14,000,000 pounds) annually. Other crops which use this pesticide as a soil fumigant include tobacco, peppers, grapes, and nut and vine crops.
When used as a commodity treatment, methyl bromide gas is injected into a chamber or under a tarp containing the commodities. About 80 to 95% of the methyl bromide used for a typical commodity treatment eventually enters the atmosphere. Commodities which use this material as part of a post-harvest pest control regime include grapes, raisins, cherries, nuts, and imported materials. Some commodities are treated multiple times during both storage and shipment. Commodities may be treated with methyl bromide as part of a quarantine or phytosanitary requirement of an importing country (these uses are exempt from the phase out). For example, the United States requires that all grapes imported from Chile and all brassware from India be treated with methyl bromide before entering U.S. commerce. Japan requires that all U.S. cherries and apples be treated with methyl bromide as a condition of import. In the U.S., the amount of methyl bromide used for quarantine purposes is small, less than 1% of total used, but with significant economic linkage to international trade and resource protection.
A structural pest control treatment with methyl bromide gas involves the fumigation of buildings for termites, warehouses and food processing facilities for insects and rodents, aircraft for rodents, and ships (as well as other transportation vehicles) for various pests. Well over 90% of the methyl bromide used in these operations eventually reaches the atmosphere.
Methyl bromide is a toxic material. Exposure to this chemical will affect not only to the target pests it is used against, but to non-target organisms as well. Because methyl bromide dissipates so rapidly to the atmosphere, it is most dangerous at the actual fumigation site itself. Human exposure to high concentrations of methyl bromide can result in central nervous system and respiratory system failure, as well as specific and severe deleterious actions on the lungs, eyes, and skin. Common initial symptoms include weakness, despondency, headache, visual disturbances, nausea, and vomiting. Later, central nervous symptoms emerge, including numbness, defective muscular coordination, tremor, muscle spasms, lack of balance, extreme agitation, coma and convulsions. Exposure of pregnant women may result in fetal defects. Depending upon dose, gross permanent disabilities or death may result. Exposed persons have developed respiratory, gastrointestinal, and neurological problems, including inflammation of nerves and organs, and degeneration of eyes. Fumigation related exposures have resulted in significantly higher incidences of throat and eye irritation, skin injuries, shortness of breath, pain in chest, nausea, fatigue, dizziness, numbness, and weakness of extremities. Exposure to high concentrations has resulted in a number of human deaths. Additional information on the health effects of methyl bromide exposure, from U.S.EPA and the U.S.Department of Health, MedNets, and the California Department of Health Services.
The Questions List.
- Why has EPA taken action on a pesticide under the Clean Air Act?
Scientific assessments conducted by atmospheric scientists under the authority of the World Meteorological Organization with the National Oceanic and Atmospheric Administration, National Aeronautics and Space Administration indicate that methyl bromide contributes significantly to the destruction of earth's stratospheric ozone layer. The most recent report, Scientific Assessment of Ozone Depletion: 1998 is now available as an Executive Summary. It contains the most up-to-date understanding of ozone depletion and reflects the thinking of 304 international scientific experts who contributed to its preparation and review. This report has given methyl bromide an Ozone Depletion Potential (ODP) of 0.4. More on the science of ozone depletion from NOAA, in FAQ #5 of this web site, and EPA.
Title VI of the Clean Air Act (Amendments of 1990) requires that all substances with an ozone depletion potential (ODP) of 0.2 or greater be phased out in the United States within 7 years. These compounds are considered "Class I" Ozone depleting substances (ODS), and cause significant damage to the earth's protective ozone layer.
The Questions List.
- When will methyl bromide be banned?
Methyl bromide production and importation will be reduced from 1991 levels as follows:
- 25% reduction in 1999
- 50% reduction in 2001
- 70% reduction in 2003
- 100% reduction in 2005
- Preshipment and quarantine uses exempt
- Critical agricultural uses allocated after 2005
- Emergency uses exempt
- When did EPA publish rulemakings for the "new" phaseout of methyl bromide?
- The 25% reduction rule was published on 6/1/99. The direct final rule for the additional reductions was published in the Federal Register on November 28, 2000. This rule implements reductions in the production and consumption of methyl bromide for 2001 and beyond, as follows: beginning January 1, 2001, a 50 percent reduction in baseline levels; beginning January 1, 2003, a 70 percent reduction in baseline levels; and, beginning January 1, 2005, the complete phaseout of methyl bromide.
- When will EPA publish a rulemaking regarding quarantine and preshipment exemptions from this phaseout?
- EPA intends to propose regulations conforming exemptions from the U.S. methyl bromide phaseout schedule for quarantine and preshipment uses with obligations under the Montreal Protocol and with the recent changes to the Clean Air Act. We plan to publish a proposal that will delineate a process for exempting quantities of methyl bromide used in the U.S. for quarantine and preshipment from the reduction steps in the phaseout schedule by early 2001.
- When will EPA publish a rulemaking regarding critical and emergency use exemptions from this phaseout?
- Consistent with congressional mandates and the Montreal Protocol, exemptions from the U.S. methyl bromide phaseout schedule for emergency and critical uses will not be available until 2005. To prepare for the period when they will be available, EPA will spend the next two years drafting a rule to conform critical and emergency use exemptions with obligations under the Montreal Protocol and the Clean Air Act. This will include the details of these exemption programs, including the submittal process, the timing, and the procedures to be used by the U.S. government in making determinations for both types of exemptions. In the meantime, to meet the exemption criteria for critical uses in the Montreal Protocol, potential applicants should be engaged in activities that will demonstrate they are pursuing alternatives.
- Are there alternatives to methyl bromide?
Yes, pest control tools exist today which manage many of the pests controlled by methyl bromide, depending on the specific target pest and crop. There is no one alternative for all of the uses of methyl bromide, but there are several pest control tools which can manage the pests currently controlled with methyl bromide. Viable alternative materials need not be identical to methyl bromide, but must effectively and economically manage those pests which are now being controlled by methyl bromide. Because methyl bromide manages a number of pests in a particular agricultural production system, it is critical to have a package of alternatives that can both control all pests which may reduce crop yield or quality and be available to growers from an economic and regulatory perspective. Research on alternatives is underway and will likely result in a wide range of options, depending on the pest and crop. While economic disparities may occur in the short-term, alternatives will likely be viable in the long-term.
The following alternatives to methyl bromide are often pest specific, and use can reduce economic pest levels when used as part of an overall integrated pest management program. While not all of the alternatives listed here are currently available to the agricultural industry, all have shown potential to control pests currently controlled by methyl bromide. Integration into current production systems will depend on availability, efficacy, logistics, economics, and grower acceptance. In all these cases, combinations of chemical and non-chemical materials and methods will likely be the most efficacious.
- What about the science linking methyl bromide to ozone depletion?
Methyl bromide is considered to be a significant ozone depleting substance (ODS) by atmospheric scientists. A recent report by the World Meteorological Organization with the National Oceanic and Atmospheric Administration, National Aeronautics and Space Administration, United Nations Environment Program, and the European Commission called Scientific Assessment of Ozone Depletion: 1998 is now available as an Executive Summary. It contains the most up-to-date understanding of ozone depletion and reflects the thinking of 304 international scientific experts who contributed to its preparation and review. A quote from that report: "The role of methyl bromide as an ozone-depleting compound is now considered to be less than was estimated in the 1994 Assessment, although significant uncertainties remain. The current best estimate of the Ozone Depletion Potential (ODP) for methyl bromide is 0.4 (with a range of 0.2 to 0.5), as compared to an ODP of 0.6 (with a range of 0.3 to 0.9) estimated in the previous Assessment (1994). The change is due primarily to both an increase in the estimate of ocean removal processes and the identification of an uptake by soils, with a smaller contribution from the change in our estimate of the atmospheric removal rate. Recent research has shown that the science of atmospheric methyl bromide is complex and still not well understood. The current understanding of the sources and sinks of atmospheric methyl bromide is incomplete."
Methyl bromide in the stratosphere comes from both natural and anthropogenic sources on earth. Natural sources of methyl bromide, such as the ocean, plants, and soil, can also be a sink for this material. For example, while the ocean was at one time considered to be a major source of atmospheric methyl bromide, it now appears to be a net sink. Scientists continue to measure atmospheric chemistry both in the troposphere and stratosphere to better understand this issue. Specific information on methyl bromide and the oceans is available from NOAA. The January 2000 "International Global Atmospheric Chemistry" (IGAC) Newsletter has several articles on methyl bromide science, including a summary of the state of knowledge on methyl bromide in the atmosphere and oceans, the effects of natural terrestrial systems upon atmospheric methyl bromide, a synopsis of the fate of methyl bromide in soils following application and factors controlling emission, and a discussion on alternatives.
While it is true that this chemical is a natural substance, the additional methyl bromide added to the atmosphere by humans can significantly upset the delecate balance in the stratosphere which allows life to exist on this planet. If methyl bromide use is not controlled in a timely manner, atmospheric scientists believe, emissions will contribute to a thinning of the ozone layer and will allow increased amounts of radiation to reach the earth's surface. This will have potential impact not only to human health, including skin cancer and the environment, but to agricultural crops as well.
- What is the Montreal Protocol? How does it regulate methyl bromide? What else is happening on the international front?
The Montreal Protocol is an international treaty developed to protect the earth from the detrimental effects of ozone depletion. Since it was begun in the late 1980's, it has been signed by over 160 countries ("Parties" to the Treaty), and controls the production and trade of ozone depleting substances on a global basis. This Treaty is now phasing out the CFCs and other ozone depleting compounds on a world-wide basis.
In 1992, the Parties to the Montreal Protocol considered the science on methyl bromide, and listed it as an ozone depleting substance with an ODP of 0.7. The Parties also agreed to freeze production in 1995 at 1991 levels, and to study the matter further.
At the 1995 meeting of the Parties, which took place in Vienna Austria (November 27 - December 7, 1995), global methyl bromide controls were added to the treaty, including a phase out for industrial nations in 2010, and a freeze in 2002 based upon an average of the years 1995-1998 for developing nations.
At the 1997 Ninth Meeting of the Parties to the Montreal Protocol (held in Montreal, Canada, 15-17/9/97), global controls (reductions in consumption) for methyl bromide were accelerated for developed (industrialized) countries: 25% in 1999, 50% in 2001, 70% in 2003, and 100% in 2005 (based on 1991 consumption levels which were frozen in 1995). For developing (non-industrialized) countries: 20% in 2005 and 100% in 2015 (based on an average of 1995-1998 consumption levels which will be frozen in 2002).
For clarification, under the control measures of the Montreal Protocol, "consumption" is defined as production plus imports minus exports.
Find out more about the Montreal Protocol or click here to download TEAP (Technology and Economic Assessment Panel) documents, including the April 1999 TEAP Report and Assessment. The United Nations Environment Program, Ozone Secretariat has recently released an excellent synthesis document covering science, environmental effects, technology and economics studies from the Montreal Protocol 1988 to 1999, and is available as a 171 page pdf file for immediate downloading and printing.
The preparatory meeting for the 1999 Montreal Protocol Meeting of the Parties, the Open Ended Working Group (OEWG) took place June 15 - 18, 1999 in Geneva, Switzerland. This was the 19th meeting of this preparatory group, and discussions have set the agenda for the 1999 Meeting of the Parties. The Report from this meeting is available on the Internet from the Ozone Secretariat. The 11th Meeting of the Parties to the Montreal Protocol took place from November 29, to December 3, 1999 in Beijing, China. Find out more about the issues discussed and decisions made at this meeting. The next meeting of the Partices to the Montreal Protocol will be the 12th, and take place December 11 - 14 2000, in Ouagadougou, Burkina Faso.
In July of 1998, the European Union announced a Proposal to ban methyl bromide in 2001. On December 21, 1998, the Environment Council reached Political Agreement on the Commission proposal for a new regulation on ozone-depleting substances. The main elements of the Political Agreement are a 60% reduction in 2001, a 75% reduction in 2003, and complete phase out in 2005. In addition, there is a cap of the use of methyl bromide for quarantine and pre-shipment at average of 1996-98 use, with a provision to further restrict this use in future as alternatives are introduced. For additional information on European Commission efforts on Ozone Protection.
The United Nations Environment Program (UNEP) has released a publication titled "Methyl Bromide Phase- Out Strategies: A Global Compilation of Laws and Regulations." The publication provides an overview of potential policy options for replacing methyl bromide, and outlines policies being followed in more than 90 nations. The report examines current uses and impacts of methyl bromide, controls contained in the Montreal Protocol, pesticide control laws, import restrictions, permitting requirements, and more. Country reports are provided by region for Africa, Asia and the Pacific region, Latin America and the Caribbean, the Middle East, other Article 5(1) nations, and non-Article 5(1) nations. The publication also features an outline of the implementing agencies of the Multilateral Fund, a description of the UNEP Division of Technology, Industry and Economics' OzonAction Program, and a list of online resources. The report is available from the UNEP website in pdf format.
Return to the questions list.
- More Questions - Latest Rumors and Innuendoes...
QUESTION: I've heard a number of different things about alternatives to methyl bromide. What's the difference between a "technical" alternative, a "viable" alternative, a "real" alternative, and a "true" alternative? ANSWER: A number of different names have been used over the past few years in discussing pest control tools to replace the use of methyl bromide. A "technical" alternative is a pest control material or method that manages the target pest that prompted the use of methyl bromide. A "viable" alternative would be something that is technically able to control the target pest, and is economically feasible and logistically workable in the real world and available from a regulatory perspective. The use of "real" and "true" alternatives appear to refer to something that is exactly like methyl bromide in chemical nature, toxicity, and application and use. Since there is only one methyl bromide, it is often said that there are no "true" or "real" alternatives to methyl bromide. While this is a true statement, it can be misleading if taken out of context. There are a significant number of technical alternatives to methyl bromide, and some of these are, or show great potential to become viable alternatives in the real world.
RUMOR: I've heard that developing nations are both major competitors of U.S. agriculture, and that these countries will have virtually unlimited use of methyl bromide through the year 2015. Is that really true? FACT: There is no question that food crops are grown in countries beside the United States, and there is often competition between the U.S. and offshore growers for the same market. However, the second part of the statement is incorrect -- developing nations now use about 27% of the global use. It is unlikely that this amount will grow significantly in the future as it will be capped shortly. As the producer countries (U.S. and Israel) phase out methyl bromide, less will be available on the world market, which will likely raise the price. As this happens, the alternatives which are currently technically feasible but more expensive than methyl bromide will become financially more attractive, and used more by both growers in the U.S. and in other countries. Thus there will actually be far more of a "level playing field" than this statement implies.
RUMOR: I've heard that methyl bromide users aren't doing anything to find alternatives to this pesticide. Is this true? FACT: This is not true. Growers that use methyl bromide currently do so because it effectively manages a number of economically significant pests, and because it has become part of an established production regime. The vast majority of growers and other users of methyl bromide are actively working (on their own, with USDA, with Land Grant Universities, or the private sector) to find alternative pest control tools that will allow them to continue to produce the same crops and control pests at a similar level as with methyl bromide. While farmers that use methyl bromide like this pesticide because it works, they are motivated to find alternatives before the phase out and most are sincerely working to this end.
Send us any rumor you've heard or question on this issue.
The Questions List.
- How can I get more information?
Call the Ozone Hot Line at 1-800-296-1996, (301) 614-3396 or contact:
- Bill Thomas
- U.S. EPA - 6205J
- 1200 Pennsylvania Ave, N.W.
- Washington, DC 20460
- TEL: 202-564-9179
- FAX: 202-565-2156
- EMAIL: thomas.bill@epa.gov
Please let us know if you know of, or will be having a methyl bromide alternatives meeting in the near future! We'll post it here!
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