Practicing safe space - what to do if there is a sudden release of biological or chemical agents into the environment
With all that is happening in our world, is there anyone left untouched by anxiety? It is infectious, like the manufactured germs we so fear and pass from father to daughter, mother to son. It is probably time, then, to pass on a few facts about what to do if there is an “event,” as the government calls it–a sudden release of biological or chemical agents into our environment.
First, for the most part, such an attack is survivable–especially if the point of dispersion was near to you, but not next door, and if you are reasonably healthy and reasonably well informed about how it all works. Of course, being prepared can improve your outcome. This article explains how to be informed, how to be prepared, and how a good immune system might save your life.
Did you know that you should seek not the lowest room in your home, but the highest? (1) Of course, this is true only with chemical attacks, because vapors tend to settle. A high room is as useful for a biological attack as any other. Because sunlight contains ultraviolet (UV) rays that can, in some cases, disarm a germ, it may even be marginally better. Certainly, holing up in a cold, damp place can lower your resistance, so why not head for, say, the master bedroom? In fact, according to the Centers for Disease Control and Prevention (CDC), you should choose a large room, preferably one with a water supply.
How long will you have to stay in your safe space? Heavy winds increase the dispersion of agents, dilute their concentration, and sometimes dehydrate them. Moderate to heavy rain tends to wash agents out of the air, but they can remain highly active where they land aground. Therefore, waiting for a good storm or a stiff wind might be useful.
How long will that take? You should be prepared for a minimum of two weeks, either secured indoors or living in post-contamination conditions where the food and water supply are not to be trusted. Have sufficient stores of food and water.
According to the American Red Cross, (2) a normally active person needs to drink at least two quarts of water each day. Hot environments can double that amount. Children, nursing mothers, and ill people may need even more. The Red Cross advises storing a total of at least one gallon per person a day and further warns that we should never ration water if supplies run low. (I do not totally agree, but remember that outdoor water supplies are likely to be contaminated and may remain problematic for some time after an event.)
Store the water in airtight containers, such as thoroughly washed plastic or, better yet, glass. Fiberglass drums are useful, as are enamel-lined metal containers. Try to siphon or tap water from its source to avoid opening the top and dipping cups or, worse, dipping your hands into the well. Store the water in a cool, dark place, and rotate it every six months; that is, use what is there and store anew.
No matter what you do, standing water is likely to stagnate. It is a perfect breeding place for microorganisms that can cause disease. Do not take the chance. If your water has been stagnant for some time, treat it before you drink it.
There are many ways to treat water, none of which is perfect. You can boil it. Bring the water to a rolling boil for 3 to 5 minutes. If you are without electricity and are enclosed in a shelter where is it inadvisable to light an open fire, however, this can become tricky.
You can disinfect water. Put 16 drops of household bleach (5.25 percent sodium hypochlorite) in a gallon of water, stir, and let stand for 30 minutes. If the water does not have a slight bleach odor, repeat the dosage and let stand for another 15 minutes. (3) Do not use scented or color-safe bleaches or bleaches with added cleaners. It is possible to get calcium hypochlorite (tablet or granular bleach) that is pre-measured. Check your camping store or any water-purification equipment supplier. (Editor’s Note: It is preferable to use pre-measured tablets as improper use of liquid chlorine bleach can cause accidental poisoning. These procedures are for emergency use only.)
You can treat water by filtration. A trip to your local camping store can be very useful. Filtration kits, used by hikers who want to avoid dubious water sources in the wild, can be used for the water in your safe space. Remember, no one mechanism has proved safe against man-made biological or chemical agents, so do not use water from outdoors until your local authorities tell you that it is safe. Be sure to read the instructions before using any filtration device to ensure that you are using it optimally.
If you are caught by surprise, you can tap some sources of water in your home, such as water in the hot water tank; be sure that the gas or electricity to the tank is off. Where you use the water from your house, shut off the incoming water valve or the main valve to the house. (4) To use this water, turn off the intake valve, then turn on a hot-water faucet. Do not turn the electricity or gas back on when the tank is drained.
Water is also hiding in pipes, ice cubes, and, as a last resort, in the reservoir of your toilet tank. Do not use the water in the bowl. To use the water from pipes, let air into the plumbing by turning on a faucet in your house located at the highest level. A small amount of water will trickle out; then use the water from the lowest faucet in the house.
So now we have a room and water. I recommend enough water for your family and a little extra so that you can shelter perhaps one or two people who were caught outside.
Before entering your space after an event has taken place, remove all of your outer clothing and leave it outside the room to cut down on the amount of the agent you carry in with you.
It is also wise to have an outer shelter, such as a foyer, to your final shelter, where there is protection in general; a doorway that can be closed and sealed when you entering the final shelter is also desirable.
Never take off any clothing by pulling it over your head. Chemical and biological agents enter through the nose, mouth, eyes, and ears. Do not pull anything over your head to remove any agents; cut the clothing off if you must.
Seal the room after you have entered it; you can use thick plastic sheeting and duct tape. Turn off any central heating or cooling, and seal off any vents. Sealing a room means cutting down on the amount of agent that enters. Unless you have a high-tech, airtight space with an air filtration and regeneration system, some air (including some pollutants) will get in. Plastic and duct tape do not create an airtight space, but they can create a “filtration system” for molecules that are larger than the pores of the plastic; those will be trapped outside. This measure should be helpful because bacteria often travel by clinging to dust particles, which tend to be larger than the pores of thick plastic sheeting.
While there is electricity in your room, it might be useful to run an air filter that removes dust. Use only the small, portable kind. I prefer ionizers because they remove dust and produce negative ions, which are beneficial molecules that help to fight odors and free radical damage. (5) They also run on little electricity.
Ionizers are advertised to remove solid particles, smoke, dust and dust mites, dead skin, pollens, insect feces, mold spores, animal and pet dander, chemicals, bacteria, microorganisms, and volatile organic compounds. Often they “remove” these items by ionizing them, causing them to drop to surfaces where they will lie. Wipe surfaces with a disinfectant cloth on a regular basis. Nonetheless, running one of these ionizers for as long as you can in your safe space should result in better air quality. Some personal ionizers run on batteries and hang around your neck. I have my doubts about the general effectiveness of these devices in the everyday world, but they might be better than nothing in a sheltered space where there is no electricity.
As for food, a trip to the local camping store will be useful. There you will find a number of specialty items that are used for hiking and camping. These foods tend to be light and easy to store, and they make well-balanced meals. Because you are likely to be without electricity, any cooking might be difficult. Dehydrated meals can be consumed without cooking; they can be very nutritious, although they might not taste good. I would not stock up on too many canned vegetables because of the high sodium content, which can complicate high blood pressure.
My personal list includes items such as these:
* canned and dehydrated fruits (raisins, apricots) or canned peaches, but not sweetened beyond their natural juice
* root vegetables (carrots, potatoes) that tend not to spoil and can be consumed without cooking if necessary
* extra virgin first cold-pressed olive oil for essential fatty acids
* apples, oranges, grapes, and figs
* whole-grain breads and cereals (without extra sugar)
Chemical reaction: In these times of heightened security, safely transporting chemicals is of paramount importance to railcar designers and railroads
The business of moving large amounts of dangerous chemicals throughout the country does not come across as the most appealing job description, yet it is one of the railroads’ largest pieces of business. According to the American Chemistry Council, chemical companies are the second largest rail shippers, paying nearly $5 billion annually in transportation costs.
The possibility of an accident leading to a spill has always been present. However, these are different days. In the wake of the Sept. 11 terrorist attacks on the U.S., fear of additional strikes, especially of a biological or chemical nature, has gripped the nation from coast-to-coast. What were once thought of as routine chemical shipments are now viewed as potential targets.
“With our changed world, security has taken on added importance in the railroad industry, “said Association of American Railroads President Edward R. Hamberger on Nov. 19 as he announced the appointment of hazmat transportation expert Dennis Delk to the new position of executive director-railroad security. Following that, the American Chemistry Council published a new manual, “Transportation Security Guidelines for the U.S. Chemical Industry,” which outlines elements of security programs and provides examples of preventative measures. Whatever new measures, if any, the railroads take, those measures must remain secret to be effective.
Railcar builders are determined to improve their safety standards when constructing cars, and some specialty suppliers are working hard to minimize the damage a spill may cause. Though the times may have changed, the idea stays the same–safety first. “We’re always working on safety improvements,” says Tom Dalrymple, executive director-tank car engineering at Trinity Rail Group. “It’s more of a situation involving steady progress than it is of radical breakthroughs. Our industry tends to evolve, so our progress is continuous.”
That progress is keeping chemical transport on railroads safe, and therefore, efficient. According to the AAR, rail is “by far and away the safest way to transport hazardous materials,” with 99.99% of hazmats traveling by rail arriving at their destination without incident. Over the past 20 years, only three fatalities have been attributable to railroad transport of hazmats. And the Research and Special Programs Administration of the U.S. Department of Transportation reports that the number of hazmat incidents per thousand carloads has declined 38% since 1990.
Trinity, a major manufacturer of tank cars for the rail industry, continues to implement various safety measures in its products to support such statistics.
Dalrymple says that Trinity tank cars are equipped with such standard safety equipment as double-shelf couplers, which reduce the likelihood of cars coming uncoupled. They also prevent couplers passing when cars are being coupled, and puncturing the end of the tank. “Double-shelf couplers have reduced coupler punctures by a large magnitude over the years, and are vital to keeping spills from occurring,” says Dalrymple.
Tank cars are also fitted with head shields, which makes them even less susceptible to puncture. “This is something that has been in existence for sometime and has proven successful,” adds Dalrymple.
Bottom outlet valve protection is a key safety feature on Trinity cars. “In case of a derailment in which a tank car comes off its trucks and has a valve on the bottom, that valve is protected with a surrounding structure to keep it from being sheered off and lading being lost,” says Dalrymple. Some cars have top-fittings protection as well, protecting valves in the event of a rollover. In constructing tank cars, Trinity also utilizes what Dalrymple calls “improved steel,” which is more tolerant of cold-weather impacts. “The name of the game is to keep the lading in the tank, and we’ve done a lot of things over the years to do just that,” he says.
Trinity is also trying to reduce the number of “non-accident” releases that can occur during chemical transport by improving gaskets to minimize splash in transit and working on human factors that contribute to spills. “A lot of the work we’re doing is training personnel, because many things that have caused problems were simple human error,” says Dalrymple.
Railroads that employ such well-designed tank cars field all of the responsibility in maintaining safer conditions on the rails. Union Pacific, for example, sponsors five-day, 40-hour courses that help train emergency response workers in assessing tank car damage, making repairs, and transferring hazmats from damaged equipment using protective clothing and self-contained breathing apparatus. The final exam includes a simulated hazmat accident, where students not only learn how to deal with dangerous chemicals, but also how to safely work around railcars and railroad property. UP has been running programs of this type since 1986.
But accidents will happen, and spills will occur, no matter how carefully a railcar is designed or how well trained the response team. And that is where companies like Trans Environmental Systems, Inc., and Portec come into play. TESI, for example, designs tools for minimizing damage that can occur with non-accident type chemical spills or leaks.
Says TESI President Merrill E. Bishop, “Our products keep the natural area around a spill safe from harmful contaminants that can seep into the ground, and we help railroads save money that can be drained by costly cleanups of such areas. And they help railroads save face with the communities through which they’re operating.”
Among TESI’s spill-containment products are the Haz-Hammock, [TM] a lightweight, 500-pound-capacity polypropylene pouch that can be suspended underneath a leaking tank car and used while the car is in motion. The company’s Spill Containment System is a 500-gallon-capacity steel pan designed to be placed on the tracks below a leak. According to Bishop, TESI’s products are now in wide use among North American railroads, including CSXT, Burlington Northern and Santa Fe, and Canadian Pacific. Norfolk Southern protects more than 60 locations along its track routes with TESI equipment.
Portec offers the Catch-All Track Mat, a containment mar that collects large spills in and around loading and unloading sites. It’s designed by Ultra Tech.
Further down the line of emergency management is a company called SAFER Systems, which uses advanced technology to help clients determine what effect a chemical release will have, in very specific terms. According to President Matt Collier, SAFER Systems’ SAFER STAR program has been implemented by BNSF. Several other Class I’s are now interested after the Sept. 11 attacks.
Essentially, the SAFER STAR allows BNSF to develop a reaction plan to a chemical spill based on factors including the specific type of chemical, and the weather conditions, population, topography, and soil type in the affected area. Using Global Positioning Satellite readings and weather reports, SAFER STAR can estimate how far and in what direction wind may blow fumes from a spill, while soil information topographical maps help determine the flow speed and direction of ground contamination. The information pre-programmed into SAFER STAR also incorporates BNSF track plans and highway/rail grade crossings, thereby enabling rapid emergency response time in case of a spill.
With all facets of the system functioning with safety in mind, transporting chemicals via rail will continue to be a safe and efficient business, no matter what the day may bring.
Three-Way Ball Valves offer chemical resistance
Electrically actuated Series 175/176/177/178 and pneumatically actuated Series 275/276/277/278 are available in PVC, CPVC, PP, and SYGEF[R]-PVDF in sizes from 1/2-2 in. with EPDM and FPM seals. Utilizing PP-GV 30 actuators for chemical resistance, valves are suited for diverting and mixing liquids in food and chemical processing piping systems. L-port version provides independent connection of inlets with outlets, while T-port version provides straight through flow.
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TUSTIN, Calif. - Oct.19, 2005 - George Fischer, Inc. introduces a new generation of 3-way actuated ball valves with the Electrically Actuated Ball Valve Series Type 175/176/177/178 and the Pneumatically Actuated Ball Valve Series Type 275/276/277/278. Offering high stability and excellent flow characteristics, these valves incorporate all the inherent advantages offered with the new EA 21 electric actuator and PA21 pneumatic actuator.
With the new actuators designed with housings made of PP-GV 30 for high chemical resistance, these actuated valves are especially well suited for aggressive fluids and the heavy-duty requirements of harsh industrial applications. Typical 3-way ball valve applications include diverting and mixing liquids in piping systems for such industries as food and chemical processing.
Both of the new 3-way actuated ball valve series are available in a PVC, CPVC, PP, and SYGEF[R]-PVDF in sizes from 1/2″ - 2″ (20mm - 63mm) with EPDM and FPM seals. Features include a 250,000 actuator cycle life for long, maintenance-free service, and compact, modular design for space savings and flexibility. The L-port version provides independent connection of inlets with outlets, while the T-port version provides straight through flow, independent connections of inlets with outlets, or interconnections of all three ports. A variety of accessories are available from position feedback to control capabilities.
The Electrically Actuated Ball Valve Types 175/176/177/178 feature a vertical (Type 178) or horizontal (Types 175, 176, and 177) configuration. The 175/176/177/178 valves incorporate the EA 21 actuator, which comes equipped with integrated emergency manual override and automatic adjustment of voltage and frequency used for on/off or process control applications. The patented manual override for these units is fully integrated into the actuator, allowing for the voltage to be interrupted and the valve manually actuated when a situation warrants. A variety of modular assemblies are available to custom-fit the valve to the application, providing high flexibility in design and operation for an optimal cost-effective solution. The EA 21 is CE and CSA certified, with UL approval pending and is available with universal automatic voltage adjustment of 100/20 VAC or a 24 AC/DC power module. Options include a cycle monitoring feature for added safety and a positioner for increased accuracy and process-safety.
The Pneumatically Actuated Ball Valve Types 275/276/277/278 feature a vertical (Type 278) or horizontal (Types 275, 276, 277) configuration, option for manual override, optional stroke limiter for accurate adjustment of the valve stop, and an ISO/NAUMR connection interface, which provides greater flexibility in adding accessories. This series is also available with extra limit switches and 1000 ohm potentiometer for position feedback.
The George Fischer, Inc. product offering includes a full range of plastic pipe, fittings, tubing, valves, actuators, rotameters, fusion machines, secondary containment, tank linings, heat exchangers, custom products, and sensors and instrumentation for industrial process control. For further information, please contact George Fischer, Inc., 2882 Dow Avenue, Tustin, CA 92780-7258; Toll Free (800) 854-4090, Fax (714) 731-6923; e-mail: us.ps@georgfischer.com; Web: www.us.piping.georgefischer.com
All trademarks are the property of their respective companies.
Not with impunity: assessing US policy for retaliating to a chemical or biological attack
Sen. Jesse Helms: Suppose somebody used chemical weapons or poison gas on people in the United States. . . . Would they damn well regret it?
Secretary of Defense William Perry: Yes.
Helms: I want to know what the response will be if one of these rogue nations uses poison gas or chemical weaponry against either us or our allies. . . . What is the response of this country going to be?
Perry: Our response would be devastating
Helms: Devastating–to them?
Perry: To them, yes. . . . And I believe they would know that it would be devastating to them.
–Testimony of Secretary of Defense William Perry Senate Foreign Relations Committee 28 March 1996
Helms: Let the message go out.
HOW SHOULD THE United States determine its response to a chemical or biological attack against American personnel or interests? The current US retaliation policy, known as calculated ambiguity, warns potential adversaries that they can expect an “overwhelming and devastating” response if they use chemical or biological weapons (CBW) against the United States or its allies. (1) Implied in this policy is a threat of nuclear retaliation, but the specifics of the US response are left to the imagination. By not identifying a specific response to an attack, this intentionally vague policy is designed to maximize flexibility by giving the United States a virtually unlimited range of response options. (2) Ambiguity gives flexibility to policy makers and enhances deterrence by keeping adversaries guessing. But there is a downside to flexibility and ambiguity. Because it is easier to prepare to execute a specific strategy than it is to prepare for a broad range of possibilities, military preparedness suffers–at least at the strategic level–under a policy of ambiguity. It is not surprising that the policy of calculated ambiguity, intended to place doubt in the minds of potential adversaries, has engendered uncertainty among those who would implement the policy. This uncertainty could manifest itself in strategic unprepared-ness. The United States needs a clearer reprisal policy, one that strikes a better balance between flexibility and preparedness.
In general, national policy should facilitate strategy development. If a policy fails to provide enough substance for making strategy, the policy should be revised. Adjectives such as overwhelming and devastating are the only guidelines that the calculated-ambiguity policy provides to strategy makers. Because current policy aims to achieve unlimited flexibility through ambiguity, the policy simply lacks enough substance to support strategy development. Without a strategy, military means may not be able to support policy ends. In making the case that the current reprisal policy hampers strategic preparedness, this article examines existing policy and assesses its strengths and weaknesses; it then suggests a means for clarifying the policy with a view toward achieving a better balance between flexibility and preparedness. Having proposed a policy that better supports strategy development, the article then presents an analytic framework consisting of four critical variables that must be considered in formulatin g strategies for responding to a chemical or biological attack.
Current Reprisal Policy
President William Clinton’s national security strategy (NSS) called weapons of mass destruction (WMD) “the greatest potential threat to global stability and security.” (3) It further stated that “proliferation of advanced weapons and technologies threatens to provide rogue states, terrorists, and international crime organizations with the means to inflict terrible damage on the United States, our allies, and U.S. citizens and troops abroad.” (4) At his confirmation hearing in 1997, Secretary of Defense William Cohen asserted, “I believe the proliferation of weapons of mass destruction presents the greatest threat that the world has ever known.” (5) Barry Schneider, director of the US Air Force Counterproliferation Center, claims that “there are perhaps one hundred states that have the technical capability to manufacture and deploy biological weapons.” (6) That Americans will be subject to a CBW attack is not a matter of if but when.
In 1969 President Richard Nixon stopped all biological weapons programs in America. More recently, the United States has begun to destroy its chemical weapons stockpile in accordance with the Chemical Weapons Convention. (7) The United States no longer has the option of responding in kind to a chemical or biological attack. This situation has made a conundrum of US retaliation policy: How best to respond to a WMD attack when the only WMDs in the arsenal are nuclear? In America’s Struggle with Chemical-Biological Warfare, Albert Mauroni writes, “Our national policy of responding to enemy use of CB [chemical and/or biological] weapons has shifted over the years from one extreme to the other; from retaliation using similar CB weapons to massive conventional retaliation to (most recently) nuclear retaliation.” (8)
Prior to the Gulf War, President George H. W. Bush and other officials let it be known that nuclear weapons might be employed against Iraq if it used WMDs against coalition forces. (9) However, in private Bush reportedly ruled out the use of nuclear weapons. (10) During Operation Desert Shield, Secretary of State James Baker coined the term calculated ambiguity to describe this policy of secretly planning not to use nuclear weapons yet publicly threatening just the opposite. (11) Defense Secretary William Perry’s testimony at hearings in 1996 on the Chemical Weapons Convention made it clear that ambiguity was still the policy of the Clinton administration. When asked what the US response to a chemical attack would be, Perry replied, “We would not specify in advance what our response to a chemical attack is, except to say that it would be devastating.” (12) When asked if the response could include nuclear weapons, he responded, “The whole range [of weapons] would be considered.” (13) Cohen, Perry’s successor, reiterated the policy in 1998: “We think the ambiguity involved in the issue of nuclear weapons contributes to our own security, keeping any potential adversary who might use either chemical or biological [weapons] unsure of what our response would be.” (14) It appears that the current Bush administration will advocate the same policy of ambiguity as did its predecessors. For example, National Security Advisor Condoleezza Rice threatens “national obliteration” to those who would use such weapons. (15) Robert Joseph, the Bush administration’s senior advisor on counterproliferation issues, argues that nuclear weapons should be an “essential component of the U.S. deterrent posture against [proliferation of WMDs].” (16)
Nuclear weapons have always been a lightning rod for controversy, so it should come as no surprise that an intense debate has been raging over the possible use of nuclear weapons in a US reprisal against a CBW attack. At issue is the decades-long clash between so-called deterrence hawks, who advocate a prime role for nuclear weapons in the calculus of deterrence, and the counterproliferation doves, who maintain that there are safer ways to deter the use of CB attacks and that the United States should reject the first use of nuclear weapons. Deterrence theory, long relegated to the proverbial back burner, is witnessing a resurgence, driven in no small part by this reprisal policy, which, when taken at face value, allows the United States to use nuclear weapons in response to something other than a nuclear attack. On the one hand, according to deterrence hawks, the potential threat to American interests from these other attacks is so large that only by threatening absolute devastation with nuclear weapons can t he United States deter such attacks. (17) The deterrence doves, on the other hand, give primacy to countering nuclear proliferation. The dove position is that the goal of nuclear nonproliferation will be irreparably damaged if America continues to maintain a policy that allows the first use of nuclear weapons. The United States should renounce nuclear retaliation, they argue, and instead threaten a massive conventional response. (18)
Evaluating Current Policy
Is the current policy of calculated ambiguity viable? In assessing that policy, one must answer two questions: What are the general criteria for evaluating a reprisal policy? To what degree does the current US policy satisfy these criteria?
Kikusui Electronics Partners with Dalian Institute of Chemical Physics to Develop Fuel Cell Evaluation Technologies
Tokyo, Japan, Oct 28, 2005 - (JCNN) - Yokohama-based electronic measurement system developer Kikusui Electronics (TSE: 6912) has exchanged a technical memorandum with the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, regarding the development of fuel cell evaluation technologies in China.
The Chinese partner is working together with the Chinese government to develop commercial fuel cell applications including fuel cell bus and car under the 863 Plan, China’s national high-tech R&D project.
Under the partnership, Kikusui aims to establish fuel cell evaluation standards for China, as well as developing cell test equipment.
Source: JCN http://www.japancorp.net
Chemical Composition, Antibacterial and Antimutagenic Activities of Essential Oil from (Tunisian) Cyperus rotundus
Abstract
Essential oil from the tubers of Cyperus ratundus, obtained by steam distillation, was analyzed by GC and GC/MS. In total, 33 compounds were identified. The oil was characterized by its high content of sesquiterpenes with cyperene (30.9%) being major. The antibacterial activity of oil from tubers of Cyperus rotundus, showed more important activity against Gram-positive bacteria specially Staphylococcus aureus than Gram-negative bacteria. The antimutagenic activity was tested by the “SOS Chromotest” and the “Ames” test. C. rotundas oil acted as an antimutagen against Aflatoxin B1 in both Salmonella strains (TA100 and TA98) and Escherichia coli strain (PQ37) and against nifuroxazide in Escherichia coli strain (PQ37), where its mutagenicity is not expressed. The highest rates of AFB1 mutagenesis inhibition tested by Ames assay, ranged from about 82.56% for TA100 strain to 85.47% for TA98 strain at the same dose of 50 µg AFB1 per plate. Whereas, the mutagenic effect of respectively nifuroxazide and AFBl (50 µg/assay) were reduced by aproximately 58.19% and 81.67% when tested by the SOS chromotest assay.
Key Word Index
Cyperus wtundus, Cyperaceae, essential oil composition, antibacterial activity, mutagenicity, antimutagenicity, SOS chromotest, Ames test.
Introduction
Cyperus rotuncliis L., a sedge of the family Cyperaceae, was collected in the region of Monastir situated in the center of Tunisia in June 2003. It is widely distributed in the Mediterranean basin areas. This plant, which grows naturally in tropical, subtropical and temperate regions, is widespread in northeast, center and south (Gabes) of Tunisia (1).
The tuberal part of C, rotuncliis is one of the oldest known medicinal plants used for the treatment of dysmenorrhoea and menstrual irregularities. It was also used as analgesic, sedative, antispasmodic and to relieve diarrhea (2). Cyperus rotundus has been widely investigated by several authors (3,4). It is a medicinal plant appearing among Indian, Chinese and Japanese traditional drugs that are used against spasms, stomach disorders and anti-inflammatory diseases (5,6).
Other pharmacological investigations indicated that C. rotundus had remarkable hypotensive, anti-inflammatory and antipyretic effects. Previous phytochemical studies showed that the major chemical components of this herb were essential oil, flavonoids, sesquiterpenes and cardiac glycosides (7).
In this study, we report on the composition analysis of essential oil from C. rotundus tubers, its antibacterial and antimutagenic activities using two tests of genotoxicity: the “SOS chromotest” and the “Ames test.”
The Aines test was further more chosen as it is a wellknown reference test that proved suitable in many similar investigations (8-11). Whereas the SOS chromotest is a widely used assay for genotoxic/antigenotoxic activity (12) that has been used for testing extracts from medicinal plants (13,14). The SOS chromotest and the Ames test detect genotoxicity by different mechanisms and thus complement each other.
Experimental
Chemicals: O-Nitrophenyl-β-D-galactopyranoside (ONPG) and P-nitrophenyl phosphate (PNPP) were purchased from Sigma, Germany. The positive mutagens Aflatoxin B1 (AFB1) and nifuroxazide were purchased from Sigma, Aldrich USA.
Plant material: Tubers parts of C. rotundas were harvested in the region of Monastir in the center of Tunisia, in June 2003. Botanical identification was carried out by Pr Chaieb (Department of Botany, faculty of Sciences, University of Sfax, Tunisia), according to the flora of Tunisia (1). A voucher specimen (CP-06.03) has been deposited in the Herbarium of the Laboratory of Pharmacognosy, Faculty of Pharmacy of Monastir, Tunisia.
Oil isolation: The oil was isolated from 100 g of the tubers parts by hydrodistillation for 2 h in 500 mL of distilled water, using the apparatus described in the 9th edition of the French Pharmacopeia cited by Bruneton (15). They were kept in vials covered with aluminium foil at 4°C (to prevent the negative effect of light, especially direct sunlight).
Oil analysis: The composition of the oil was investigated by GC and GC/MS. GC analysis was performed with chromatograph HP5890 equipped with a flame ionization detector (HP5 30 m x 0.25 mm fused silica capillary column, film thickness 0.25 µm). Injector and detector temperature were set at 240°C and 280°C, respectively. The oven temperature program was 50°C for 3 min, then 50°-280°C at 9°C /min, and 280°C for 3 min. Nitrogen was employed as carrier gas at a flow rate of 1 mL/min. The volume injected was 0.1 µL, of oil diluted in hexane (10%). The percentage composition of the oils was recorded from the GC peak areas without using any correction factors.
The sample was analyzed by GC/MS using a HP5972/A mass spectrometer recording at 70 eV at the same conditions as described above in GC analysis. The identification of compounds was performed by comparison of retention indexes (determined relatively to the retention times of a series of n-alkanes) with those of authentic standards of a mass spectra library (Wiley 275.1) (16).
Bacterial strains: The following bacteria were used: Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Salmonella enteritidis ATCC 13076, and Salmonella typhimurium NRRLB 4420.
Esherichia coli PQ37 strain was kindly provided by Pr.Quillardet, (Institut Pasteur of Paris, France). The complete genotype, as well as strain construction details are described by Quillardet et Hofnung (17). Frozen permanent copies of the tester strain were prepared and stored at -80°C.
Histidine-dependent strains, Salmonella typhimurium TA100 and TA98, were provided by Pr Quillardet (Institut Pasteur of Paris, France) and maintained as described by Maron et Ames (18). Strain TA98 allows detection of frameshift mutations. This strain contains the plasmide pKM 101 and the products of the muc AB genes on this plasmid enhance SOS mutagenesis, thereby making strain TA98 more responsive to certain mutagens as AFB1. Whereas, TA100 strain is the most sensitive of all of the Salmonella typhimurium tester strains (19) particulary against AFB1. The genotypes of the test strains were checked routinely for their histidine requirement, deep rough (rfa) character, UV sensitivity (uvr B mutation) and presence of the R factor. They were stored at -80°C.
S9 fraction and S9 mix: The S9 microsome fraction is prepared from rats treated with Aroclor 1254 (18). The composition of the activation mixture for SOS chromotest was the following per 10 mL of S9 mix: salt solution (1.65 M KCl, 0.4 M MgCl^sub 2^ 6H^sub 2^O) 0.2 mL; Glucose-6-Phosphate (1M) 0.05 mL; NADP (0.1 M) 0.15 mL; Tris buffer TRIS (0.4 M pH 7.4) 2.5 mL; L medium (Bacto tryptone 10 g, Bacto yeast extract 5 g, NaCl 10 g/L of distilled water) 6.1 mL; S9 1 mL (17).
The components of S9 mix for Ames test were 0.4M MgCl^sub 2^, 1.65 M KCl, 1 M Glucose-6-Phosphate, 0.1 M NADP, 0.2 M sodium phosphate buffer, pH 7.4, and S9 at a concentration of 0.04 mL/mL of mix. The S9 mix was prepared freshly for each assay (18).
Antibacterial assay: Antibacterial activity of the oil was determined using the microdilution agar technique (20), with some modifications; the emulsion of the oil in agar 1% was obtained by sonication of the mixture at 7 volts power. Overnight grown bacterial suspensions were standardized to approximately 105 cells/mL (21). Ninety-six well-microtiter plates were used. In each well, 100 µL of microbial suspension was added to 100 μL of the test oil dilution. The last row containing only agar and bacterial suspension served as a positive growth control. After incubation at 37°C for 24 h with shaking, the first well without turbidity was determined as the minimal inhibition concentration (CMI) (22, 23).
SOS chromotest assay: The SOS chromotest assay is a bacterial test for detecting DNA-damaging agents. It involves a set of functions known as the SOS responses. We have taken advantage of an operon fusion placing lacZ, the structural gene for β-galactosidase, under control of the SfiA gene, an SOS function involved in cell division inhibition, to devise a simple and direct colorimetric assay of the SOS response to DNA damage (12). It is also constitutive for alkaline phosphatase (AP) synthesis.
An overnight culture of E.coli PQ37 (100 µL) was added to 5 mL of fresh medium and incubated for 2 h at 37°C. One mL of this culture approximate cell density 2×10^sup 8^ cell/mL was diluted with 9 mL of nutrient broth or 9 mL of S9 mix. A fraction of 0.6 mL was transferred into a series of glass test tubes, each containing 20 µL gradual dilutions of the compound to be tested. The mixtures were incubated with shaking for 2 h at 37°C. After this, two equal sets of tubes were filled with 0.3 mL of each incubated mixture.
Chemical Christmas: immigrant tree farm workers face pesticide dangers
Every Christmas, little Katie Alvarez asks her daddy for two trees, one for her formal living room, and one for the family room. Katie has no idea what those trees might cost her father. Treating Christmas tree fields each spring, farm-worker Felix Alvarez, 43, soaks his skin with Roundup, a weedkiller linked to cancer among applicators. “Later on, when I get older, I’ll probably have some consequence about it because I’ve been getting wet all over,” Alvarez says.
Second only to Oregon, the state of North Carolina produces roughly one out of five Christmas trees sold in the U.S.–about five million a year, worth more than $100 million. Each spring and summer, Hispanic workers like Alvarez handle some of the deadliest pesticides allowed by law, potentially risking their health to help Americans celebrate life.
Fifty million Fraser firs grow on 25,000 acres in the mountains of North Carolina, and almost every acre is treated with Roundup. A salt compound, Roundup can irritate the eyes and is toxic when inhaled. In 1999, the American Cancer Society published the results of a survey of non-Hodgkin’s lymphoma patients showing the disease was 2.7 times more likely among those who had applied glyphosate, the herbicide sold under the “Roundup” trade name.
The most hazardous and second-most common pesticide in North Carolina Christmas tree farming is Di-Syston 15-G, a powder traditionally applied with a bucket and measuring spoon. “If one grain gets in your boot, and your foot sweats, by the end of the day, you could be dead” says Richard Boylan, an alternative agriculture agent with the North Carolina State University Cooperative Extension.
Last year, Bayer CropSciences voluntarily discontinued Di-Syston 15-G for all crops other than Fraser firs in North Carolina and coffee in Puerto Rico. U.S. farms had previously used it for food crops such as Brussels sprouts, cabbage, cauliflower, peanuts and peppers. The EPA had threatened to ban it completely, but North Carolina’s Christmas tree growers worked to develop a new closed-system applicator that enables workers to pour the granules from a stainless-steel spout rather than scooping them from an open bucket. “We believe that the granular risks can be adequately mitigated by closed systems,” says EPA spokesperson Enesta Jones.
Christmas tree farmers use Di-Syston to control balsam twig aphids in the spring, and its residues prevent spruce spider mites throughout the year. The aphids cuff needles and stunt growth in firs, sometimes enough to make them worthless; the spider mites discolor evergreen needles by sucking their sap.
“If they lost [Di-Syston] and didn’t come up with something that would take its place, you can put the Christmas tree business out of business,” one grower told Wake Forest University researcher Pamela Rao in a paper published in Human Organization.
Ever since a public outcry over childhood leukemia in the early 1990s, growers have been cutting pesticide use through a technique called Integrated Pest Management, which targets chemicals only where they’re really needed. Between 1994 and 2000, growers reduced Di-Syston use from 65 percent of total acreage to 50 percent, according to North Carolina State Christmas tree specialist Jill Sidebottom.
“The industry has grown a lot,” says Debbie Fishel, whose Grouse Ridge Farms employ 30 to 60 Hispanic workers each year. “I live in the same area they do and drink the same water. I am exposed to the same environment they are, and we have become aware of the risks.”
As they have reduced reliance on Di-Syston, growers have increased the spread of other insecticides, including Dimethoate, Lindane and Asana, all slightly or moderately toxic chemicals. Though Lindane is the least immediately harmful of these, the EPA banned it in 2002 for its chronic effects and persistence in the environment.
Like Di-Syston, Dimethoate is an organophosphate that can cause numbness, tingling sensations, headaches, dizziness, tremors, nausea, abdominal cramps, sweating, blurred vision, difficulty breathing and slow heartbeat, experts say.
Asana is another spray that controls the balsam woolly adelgid, a European insect that has devastated Fraser firs in forest stands, flattening their tops, swelling their joints and hardening their wood. A worker poisoned with Asana could experience dizziness, burning, itching, blurred vision, tightness in the chest, convulsions, nausea, vomiting, headache, weakness or tremors, according to EXTOXNET, a network of university cooperative extension offices from across the United States. As with Dimethoate, swallowing less than two tablespoons of Asana can kill a grown man.
“Asana can make your skin burn for about six hours” said one Christmas tree worker in 2001. “Sometimes I can’t sleep at night because my face burns so much. I use a mask and glasses, but there are still parts of my face that aren’t covered, and the spray gets on your face anyway.”
A Wake Forest public health professor, Thomas Arcury, has led a series of studies on pesticide exposure among Christmas tree workers, finding chemical traces in their homes, on their children’s hands and toys, and in family urine samples. One study concluded that growers do not take the threat seriously enough. They sometimes neglect their own personal protective equipment, setting a poor example for the workers. Assessing the level of risk is a point of contention among growers, the public and even the experts. Though workers share anecdotes of pesticide poisonings and neighbors worry about groundwater contamination, not one case of long-term illness has been linked to Christmas tree farming in North Carolina.
“I can’t prove that you’re going to get sick 20 years from now,” says Arcury. “We don’t have any direct evidence like that. However, if you look at the preponderance of all the scientific evidence … then we would have to argue that there is, in fact, an increased risk.” CONTACT: Pesticide Action Network, (415)981-1771, www.panna.org.
Chemical Stability of Perphenazine in Oral Liquid Dosage Forms
Abstract
The stability of perphenazine in oral liquid dosage forms was studied by means of a stability-indicating high-performance liquid chromatography assay method that was developed in our laboratory. There was a direct relationship between the peak heights and the concentrations, with an r value of 0.998. The percent relative standard deviation based on five injections was 0.6. The products of decomposition and excipients present in the dosage forms did not interfere with the developed assay method. The dosage forms were stable for only 30 days when stored in amber-colored glass bottles at room temperature. The pH value of the mixtures remained constant at 3.7 after 90 days of storage, and the physical appearance of the mixtures did not change. The beyond-use date of 30 days is recommended for this product.
Introduction
Perphenazine is a phenothiazine derivative similar to chlorpromazine (Figure 1). It exerts moderate anticholinergic and sedative effects, and also strong extrapyramidal and antiemetic activities. A formula for compounding an oral liquid dosage form of perphenazine has been reported.1 As no stability studies had been reported for this formulation, the default beyond-use date assigned was 180 days based on the guidelines reported in the United States Pharmacopeia-National Formulaiy (USP-NF).2
The purposes of this investigation were (1) to develop a stability-indicating high-performance liquid chromatographic (HPLC) assay method for the quantitation of perphenazine, and (2) to study the stability of perphenazine in oral liquid dosage forms.
Materials and Methods
Chemicals and Reagents
All the chemicals and reagents were USP-NF or American Chemical Society (ACS) grade and were used without further purification. Perphenazine powder (Lot 74509) was generously supplied by Professional Compounding Centers of America, Houston, Texas.
Equipment
An HPLC system (ALC 202 pump and model 484 multiple wavelength detector; Waters Corporation, Milford, Massachusetts) equipped with an injector (Model 7125; Rheodyne, Cotati, California) and a recorder (Omniscribe 5213-12; Houston Instruments, Austin, Texas) were used. The column used (microCN, 15 cm, 4.6 mm ID, 5 µm) is available from Waters Corporation. All pH values were measured using a Beckman SS-3 Zeromatic pH meter (Beckman Instruments, Fullerton, California).
Chromatographic Conditions
The mobile phase contained 50% (v/v) acetonitrile in water containing 1% of glacial acetic acid and enough 85% phosphoric acid to set the pH at 2.6. The flow rate was 1.2 mL/minute, the sensitivity was 0.9 AUFS at 257 nm, the chart speed was 30.5 cm/hour, and the temperature was ambient.
Preparation of Oral Liquid Dosage Forms of Perphenazine
The oral liquid dosage forms (0.5 mg/mL) were prepared according to a previously published formulation,1 except that anhydrous citric acid (50 mg per 50 mg of the drug) was used to assist in dissolution of the perphenazine instead of 5 mL of glycerin. Dissolving the drug in glycerin was extremely difficult; moreover, citric acid is a component of Ora-Sweet, the vehicle recommended.1 For both of the preparations, Ora-Sweet was used as the vehicle. One of the dosage forms contained 0.1% sodium metabisulfite as an antioxidant, and the other did not contain any antioxidant. The initial pH value of both formulations was 3.7. The ingredients were (per 100 mL) perphenazine 50 mg; water 5 mL; citric acid anhydrous 50 mg; and Ora-Sweet (Lot 3H6754, Paddock Laboratories, Minneapolis, Minnesota) qs to 100 mL. Although the pH of Ora-Sweet has been reported to be approximately 4.2, the lot of Ora-Sweet we used for the study, which had been stored in our lab (no expiration date was indicated on the product’s label), had a pH value of 3.5. Even the pH value of 4.2(1) is not within the range (4.5 to 4.9) of a commercially available oral concentrate solution.1 Before bringing to volume with Ora-Sweet, 50 mg of the drug was dissolved in 5 mL of water containing 50 mg of citric acid. After the initial data (assays, pH values, and physical appearance), the dosage forms were stored at room temperature (25°C) in 240-mL amber-colored glass bottles (Owens-Illinois, Toledo, Ohio). Data were collected at the appropriate intervals.
Preparation of Standard Solutions
The stock solution of perphenazine (0.5 mg/mL) in water containing 50 mg of citric acid was prepared fresh daily using a simple solution method. The stock solution was used to prepare solutions of lower concentrations as needed by diluting with water. The most commonly used standard solution contained 50 µg/mL of perphenazine.
Preparation of Assay Solutions
A 5.0-mL quantity of the assay mixture was diluted to 50 mL with water.
Decomposition of Perphenazine
A 25-mL quantity or the standard solution (50 µg/mL) was transferred to a 150-mL beaker and heated to boiling on a hot plate. More water was added to the solution as needed. After 45 minutes, the solution was allowed to cool, the volume was brought to 25 mL with water, and the solution was injected into the chromatograph using the following procedure. The results are presented in Table 1.
Assay Procedure and Calculations
An 80-µL quantity of assay solution was injected into the chromatograph under the described conditions. Since there was a direct relationship between the peak heights and the concentrations (range tested, 25 to 55 µg/mL with an r value of 0.998), the results were calculated using a standard curve (Figure 2). The results are presented in Table 1.
Results and Discussion
Assay Methods
The developed HPLC assay method is stability indicating, since the product of decomposition did not interfere with the assay procedure (Figure 3). Furthermore, the inactive ingredients presented in the dosage form (i.e., citric acid, sucrose, glycerin, sorbitol, sodium phosphate, flavor, methylparaben, sodium benzoate) did not interfere with the assay procedure. The standard solution, which was decomposed using heat, lost approximately 48% of its potency (Table 1). There was a direct relationship between the peak heights and the concentration of the drug (range tested, 25 to 55 µg/mL). The developed method is accurate and precise with a percent relative standard deviation based on five injections of 0.6 and an r value for the standard curve of 0.998.
The assay results indicate that perphenazine was stable for only 30 days in both of the oral liquid dosage forms when stored in amber-colored glass bottles at room temperature (Table 1). The pH value of 3.7 for both the formulations remained constant, and the physical appearance did not change after 90 days of storage. The previously recommended default beyond-use date of 180 days1,2 is not appropriate for perphenazine in this vehicle. The percent of intact drug remaining after 62 days was 87.8% in the solution with an added antioxidant (sodium metabisulfite) and 83.3% in the solution without an antioxidant. Thus the antioxidant offered only a marginal improvement. It is well known that the phenothiazine derivatives are subject to oxidation,3 and the oxidation is catalyzed by light. In this investigation, the pH value of the dosage forms was 3.7, while the predicted value was 4.2.1 This deviation from predicted pH may have affected the stability of perphenazine. Even the pH value of 4.2 is not within the pH range (4.5 to 4.9) of the commercially available oral concentrate solution.1
The decomposition of perphenazine followed first-order law (Figure 4), and the product of decomposition (peak 2 in Figure 3) was from perphenazine sulfoxide.4 The author is presently investigating the stability of new dosage forms of perphenazine in (1) a current lot of Ora-Sweet at a pH value of 4.2, and (2) a different commercially available syrup with a pH value of 4.5; these results will be reported later. Preliminary findings indicate that the results at pH 4.5 are encouraging, while those in the recommended Ora-sweet vehicle (pH 4.2) are not.1
References
1. Allen LV Jr. Perphenazine 2.5-mg/5-mL syrup. IJPC 2003; 7(6): 473.
2. US Pharmacopeial Convention, Inc. United States Pharmacopeia 26-National Formulary 21. Rockville, MD: US Pharmacopeial Convention, Inc.; 2002:2197-2201, 2574.
3. Ravin LJ, Kennon L, Swintosky JV. A note on the photosensitivity of phenothiazine derivatives. J Am Pharm Assoc (Baltim) 1958; 47(10): 760.
4. Beaulieu N, Lovering EG. Liquid chromatographic method for perphenazine and its sulfoxide in pharmaceutical dosage forms for determination of stability. J Assoc Off Anal Chem 1986; 69(1): 167-169.
Vishnu D. Gupta, PhD
Pharmaceutics Division
University of Houston
Houston, Texas
Address correspondence to Vishnu D. Gupta, PhD, Pharmaceutics Division, University of Houston, 1441 Moursund Street, Houston, TX 77030. E-mail: vgupta@uh.edu
Copyright International Journal of Pharmaceutical Compounding Nov/Dec 2005
Provided by ProQuest Information and Learning Company. All rights Reserved
Sumitomo Chemical Files Suit Against Pfizer for Amlodipine Besilate
Tokyo, Japan, Nov 2, 2005 - (JCNN) - Sumitomo Chemical announced on November 1 that it and its subsidiary Dainippon Sumitomo Pharma have jointly filed suit against Pfizer in the Tokyo District Court on the same day.
In response to a preliminary injunction petition filed by Pfizer in October, the two companies seek a declaratory judgment that their right to manufacture and sell amoldipine besilate remains valid. Amoldipine besilate is a hypertension drug discovered by Pfizer.
Since 1991, Pfizer and Sumitomo Pharamceuticals, one of the two predecessor companies of Dainippon Sumitomo Pharma, have entered into a licensing agreement for amoldipine bestilate.
Sumitomo Pharmaceuticals has been marketing the agent under the trade name of Amoldin since then.
Source: JCN http://www.japancorp.net
Water shutoff chemical restores production: a spectacular well had to be taken offline as water breakthrough had overwhelmed facilities. Here’s how the problem was fixed in this North Sea well
Centrica Resources, Ltd, has extended the productive life of a subsea production well in Rose field in the southern North Sea, using a rigid-setting fluid as a zonal isolation material to alleviate excessive water production. This water-management treatment helped bring the well back onstream after it had been shut-in due to excessive water production.
Initial gas production from the well was 120 MMcfd before water production began. After treatment, the well returned to its prior glory, but was recently choked back to 70 MMcfd, with a water-to-gas ratio (WGR) of less than 2 bbl/MMcf. Rose field is produced from a single subsea well that crosses two faults, with the trajectory of the well dipping at the end of the horizontal section.
The well, 47/51b-6w, is located about 54 km northeast of Humberside, UK. After only 2.3 Bcf of production, the well was shut-in because water production rates exceeded the capacity of the terminal. The increase in salinity indicated that the water was coming somewhere near the producing formation. Because the formation was unconsolidated, the well was originally completed with pre-packed, wire-wrapped screens in open-hole, so simply setting a plug to isolate the water was not feasible. (1)
A COST-EFFECTIVE SOLUTION
Three solutions were identified to address the water-cut problem:
1. Temporarily suspending the well using mechanical or chemical plugs until a viable technique was developed to allow production. This would, of course, result in lost revenue for an unknown period.
2. Sidetracking the present wellbore and tapping the reservoir by an alternate route presented substantial re-drilling costs.
3. Performing a remedial intervention using a chemical water shutoff treatment would help prevent the water influx while allowing continued gas production. This alternative presented the best economic and technical risk.
The intervention was designed for a jackup environment, located over a subsea well. This included coiled tubing (CT) and fluid pumping operations. The water-producing interval was in a horizontal completion. The basic idea was to seal off this interval, as well as isolate the unsupported annulus between the water-bearing and gas-producing intervals. This challenge required placement of a suitable Zonal Isolation Material (ZIM) that would set quickly without slumping, and set mechanical barriers, all while leaving the upper portion of the well undamaged.
Zonal isolation material. The key component (Fig. 1) in the successful water shutoff was the application of the selected ZIM–a Rigid-Setting Fluid (RSF) with a predictable and controllable right-angle set. (The term “right-angle set” is based on the extreme 90[degrees] turn shown on a graph of viscosity vs. time.) This right-angle set is possible because of the fluid’s capability to remain at a low viscosity during fluid placement. It then sets rapidly for a given formation temperature.
The setting process is an exothermic reaction; therefore, the setting time is exponentially accelerated, giving a very short liquid-to-solid transition time. Because of the rapid transition between the fluid state and the solid state, gas migration is anticipated to be zero. As it sets, the material rapidly develops a high-compressive strength; for example, it can reach 3,000 psi within two hours. The material also has zero shrinkage, yet can be removed by drilling, milling or acid. It can also tolerate up to 50% fluid contamination with only a slight reduction in compressive strength development.
The ZIM was engineered to function in a combination of a displacement time of 35 min. and a temperature-related-delay setting time of 8 min. at the bottomhole temperature of 200[degrees]F. Because the displacement time begins only when the temperature begins to increase, the treatment can be mixed ahead of time on surface.
Equipment used.
A 95k injector was used, along with the following equipment:
* Tapered coiled tubing of 1 3/4-in. OD, 100-kpsi yield strength, with backup String
* Tubing guide arch with a 100-in. Radius
* 4.06-in. side door with a 5.12-in. radial stripper combination
* 4.06-in. triple-combination BOP configured with a shear/seal, a slip and a pipe ram
* A riser quick-connection sub to minimize the time spent pressure-testing the surface riser connections
* Subsea lubricator cutting valve to eliminate the need for an additional BOP, with a blind/shear configuration
* Data acquisition system to monitor and record string depths, running speeds, weights, well pressure, tubing pressure, pump rates and pump volumes
* One V8 well-services fluid pump
* A twin compartment, 25-bbl blender.
Implementation process. To begin the operation, the jackup was moved into position. A 7-in., flexible subsea riser was connected to the wellhead via an ROV.
Next, a drift cleanup run was performed with a regular, centralized bull-nose jetting nozzle to help ensure that the CT could be run to the target of 13,600-ft MD. Initial software simulations had indicated that, if too much gas was present, it might interfere with reaching this depth, which was essential for required Memory Production Logging Tool (MPLT) runs. With the well shut-in, the CT reached a 13,600-ft MD.
The MPLT runs were performed under both flowing and non-flowing conditions, to determine where the water influx was being produced. After the water-producing region was identified in the toe of the well, a tubing punch, with 11 ft of perforating guns and a pressure-activated firing head, was used to access the annulus between the 4.5-in. tubing and openhole section at 12,650 ft.
The watered-out lower completion was isolated by setting an inflatable bridge plug at 12,750 ft, Fig. 2. The bridge plug acted as a base for the ZIM treatment in a later step of the process and sealed off the lower part of the wellbore.
A retrievable packer was then set at 12,050-ft MD on CT, Fig. 3. The CT bottomhole assembly comprised a motor-head assembly, weight stem, centralizers and a squeeze packer. After the packer was set, an injection test was performed while the CT was still attached to the packer, to determine what flowrates could be achieved through the tubing perforations, as well as the required surface pump pressures. After determining these rates and pressures, the ZIM was pumped through perforations in the 4.5-in. tubing at 12,650 ft into the unsupported annulus, Fig. 4. In the horizontal well section, the ZIM was sandwiched between highly viscous gel pills to help prevent slumping of the ZIM plug.
[FIGURE 3 OMITTED]
ZIM placement details. With the CT still stabbed into the squeeze packer, the treatment was placed using 2 bbl of viscous-gel lead spacer, 15 bbl of ZIM and 5 bbl of crosslinked-gel tail spacer. The treatment was pumped into the annulus at a rate of 0.75 bbl/min, with a pump pressure of 4,500 psi until the treatment was over the tubing guide arch, and pumped at 2,000 psi thereafter.
The ZIM set within 43 min., at which point the squeeze packer was unset and the CT was moved to above 10,000 ft, while 5 bbl of water was circulated through the CT to ensure it was clean and free of the treatment chemicals.
The ZIM generated sufficient compressive strength within five hours, and the well was flowed for testing. Another MPLT run was performed to determine whether the ZIM treatment had been successful in preventing water production from the well, Fig. 5. Flow rates equivalent to 40, 60 and 80 MMcfd gas were established.
Results. The CT intervention operations were completed in 372 hours, about seven hours of which were nonproductive time, including time spent waiting for acceptable weather conditions. Before intervention, MPLT logs showed water holdup from 12,900-ft MD–the region just above the perforated interval at the toe of the well–to 10,900 ft–the region just below the perforated interval at the heel of the well. This indicated that water was being produced from the toe section. This same log shows that the only water holdup in the well is at the heel section, but this was only a mist and could be considered extremely small. Post-operation checks show no flow coming from the original toe section after intervention.
Water-to-gas ratio (WGR) of less than 2 bbl/MMcf was achieved after the intervention had been completed. The WGR has steadily decreased since the intervention took place and is now considerably lower than 2 bbl/MMcf. There has also been a steady reduction in chloride ions found in produced water from the well. This decrease in salinity levels indicates that the produced water is the seawater lost during the intervention, not reservoir water. The intervention proved the chosen solution and the Rose well is currently producing in excess of the forecast post-recovery rate.
LITERATURE CITED