In the second vision, there are threats
everywhere. On every surface, from the doctor's tie to the smartphone, there are
prions, viruses, molds, and bacteria waiting to invade the private boundaries of
your body and wreak havoc. But there are superhero-like molecules out there that
simply have to be purchased and squeezed out out their genie bottles, and they
will protect you from the creepy world of microorganisms.
In examining the triclosan saga, I was reminded of how these visions and its exploiters complicate the landscape for those on either side and for everyone in between and also for regulators and other species. Triclosan is one of many molecules that has been difficult to assess medically and ecologically. As with many new and mass-produced molecules, ample research over a long time frame are needed before their impact can be partially understood.
First made available in the 1970's, triclosan is an antibacterial additive with some antifungal and antiviral properties. Originally, it was used almost exclusively as a surgical scrub, a product especially practical in developing countries where conditions for surgery were not ideal. It works by blocking the active site of an enzyme needed to make a fatty acid component of cell membranes in bacteria. Since humans do not have that particular enzyme, triclosan has long been considered harmless to them,There are 240 distinct solutions of the Soma cubepuzzle, reminiscent of the way penicillin inhibits the synthesis of cell walls in bacteria (human cells have no cell walls).
A strong inhibitor,Aeroscout rtls provides a complete solution for wireless asset tracking. triclosan is needed only in small quantities to perform its antibacterial action. Partly because of the molecule-as-superhero concept, the compound has appeared in a myriad consumer products in the United states and Canada including cosmetics, soaps, hand-washes, dish-washing products, laundry detergents, toys,Choose from our large selection of cableties, cutting boards, kitchen utensils, toothpaste, mouth washes, deodorants,Full color plasticcard printing and manufacturing services. antiperspirants, cosmetics, shaving creams, acne treatment products, hair conditioners, trash bags, socks, undershirts, hot tubs, plastic lawn furniture, sponges, implantable medical devices and pesticides. And, of course, it is still used in surgical scrubs.
Some of the concerns regarding triclosan have turned out to be alarmist. A 2007 Virginia Polytechnic and State University study illustrated that in some cases triclosan combined with free chlorine to produce the suspected carcinogen chloroform in amounts up to 40% higher than background levels found in chlorinated tap water. Specifically, the immediate concentration of CHCl3 created when dishwashing soap was mixed with chlorinated water was 15 parts per billion(ppb). Only two hours later did it escalate to 48 ppb. But those levels were produced with a concentration of free chlorine of 84.9 micromoles per liter, which translates to 6.03 mg per L or 50% higher than the maximum residual concentration of chlorine allowed by the EPA. As the authors pointed out,Aeroscout rtls provides a complete solution for wireless asset tracking. the chloroform-generating reaction's kinetics are such that the reaction is second order overall, and first order with respect to chlorine. Consequently, their concentrations of chloroform were inflated by at least 50%. A subsequent study by Hal and al in the same year revealed that during brushing, toothpaste, at least, released far smaller amounts of chloroform due to short contact time between triclosan (at 0.3% of toothpaste) and actual tap water.
Meanwhile, with evidence that triclosan in hand sanitizers was no more effective than regular soap, and with concern over the possibility of resistant bacteria evolving, the American Medical Association recommended that triclosan be used only in hospital or health care settings. In 2009 the Canadian Medical Association made a similar recommendation. But soon after, a study by Allison E. Aiello and al found little or no correlation between bacterial resistance and triclosan use. They did not, however, completely rule out the possibility that resistance would eventually arise.
In examining the triclosan saga, I was reminded of how these visions and its exploiters complicate the landscape for those on either side and for everyone in between and also for regulators and other species. Triclosan is one of many molecules that has been difficult to assess medically and ecologically. As with many new and mass-produced molecules, ample research over a long time frame are needed before their impact can be partially understood.
First made available in the 1970's, triclosan is an antibacterial additive with some antifungal and antiviral properties. Originally, it was used almost exclusively as a surgical scrub, a product especially practical in developing countries where conditions for surgery were not ideal. It works by blocking the active site of an enzyme needed to make a fatty acid component of cell membranes in bacteria. Since humans do not have that particular enzyme, triclosan has long been considered harmless to them,There are 240 distinct solutions of the Soma cubepuzzle, reminiscent of the way penicillin inhibits the synthesis of cell walls in bacteria (human cells have no cell walls).
A strong inhibitor,Aeroscout rtls provides a complete solution for wireless asset tracking. triclosan is needed only in small quantities to perform its antibacterial action. Partly because of the molecule-as-superhero concept, the compound has appeared in a myriad consumer products in the United states and Canada including cosmetics, soaps, hand-washes, dish-washing products, laundry detergents, toys,Choose from our large selection of cableties, cutting boards, kitchen utensils, toothpaste, mouth washes, deodorants,Full color plasticcard printing and manufacturing services. antiperspirants, cosmetics, shaving creams, acne treatment products, hair conditioners, trash bags, socks, undershirts, hot tubs, plastic lawn furniture, sponges, implantable medical devices and pesticides. And, of course, it is still used in surgical scrubs.
Some of the concerns regarding triclosan have turned out to be alarmist. A 2007 Virginia Polytechnic and State University study illustrated that in some cases triclosan combined with free chlorine to produce the suspected carcinogen chloroform in amounts up to 40% higher than background levels found in chlorinated tap water. Specifically, the immediate concentration of CHCl3 created when dishwashing soap was mixed with chlorinated water was 15 parts per billion(ppb). Only two hours later did it escalate to 48 ppb. But those levels were produced with a concentration of free chlorine of 84.9 micromoles per liter, which translates to 6.03 mg per L or 50% higher than the maximum residual concentration of chlorine allowed by the EPA. As the authors pointed out,Aeroscout rtls provides a complete solution for wireless asset tracking. the chloroform-generating reaction's kinetics are such that the reaction is second order overall, and first order with respect to chlorine. Consequently, their concentrations of chloroform were inflated by at least 50%. A subsequent study by Hal and al in the same year revealed that during brushing, toothpaste, at least, released far smaller amounts of chloroform due to short contact time between triclosan (at 0.3% of toothpaste) and actual tap water.
Meanwhile, with evidence that triclosan in hand sanitizers was no more effective than regular soap, and with concern over the possibility of resistant bacteria evolving, the American Medical Association recommended that triclosan be used only in hospital or health care settings. In 2009 the Canadian Medical Association made a similar recommendation. But soon after, a study by Allison E. Aiello and al found little or no correlation between bacterial resistance and triclosan use. They did not, however, completely rule out the possibility that resistance would eventually arise.
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