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> > Пить минеральную воду постоянно также вредно, как не пить её вообще

Они вынуждены покупать питьевую воду. По натуре своей, отчасти это вызвано еще совдепоским временем, я привык все проверять. Возьмите проверьте и Вы. В аквариум с растениями, рыбами и беспозвончными поместите кусочек медной трубы и засеките время. Первыми склеят ласты беспозвончные, потом растения, рыбы последние. Это безусловно жестокий опыт, но не менее жестокие опыты ставят на мышках, кроликах и т.д. при проверке косметики. Я думаю это даст достаточно пищи для выводов.
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> Проверять не стала, поверила Вам на слово. Именно для этого и существуют определенные нормы, которые контролируют содержание меди в воде....
На самом деле не склеят они ласты - купил он Вас !!!! Водицу-то обновляют и в аквариуме иногда. Ученые даже термин такой придумали - bioavailability? BLM (biotic ligand model) и т.д.
Суть в том, что все элементы периодической системы в той или иной мере присутствуют в окружающей среде и, скорее ДА чем НЕТ потребны живым существам в том или ином количестве. Вопрос именно с этом КОЛИЧЕСТВЕ.
Так вот, меди в акватической (водной) среде МНОГО, она потребна ! Медь является НЕОТЕМЛЕМОЙ частью ежедневного рациона человека! Отсутствие меди в рационе приводит к деформациям, равно как и ее излишнее количество.
Недостаток меди в рационе беременных приводит к паталогиям и отрицательно сказывается на росте плода!
Но у меди есть одно замечательное свойство - ее "излишек" невозможно не заметить! При излишке меди в воде появляются пятна на раковине, а самом вода приобретает отчетливый кисло-металлический вкус, не заметить который невозможно. В отличие от сложных органических веществ без вкуса и запаха, выделяемых полимерами.
Ну а по делу - ЛЮБОЙ материал имеет свои преимущества и недостатки. Преимущества и недостатки меди изучены вдоль и поперек и остается только пользоваться этими знаниями, что нормальные люди и делают.
А вот гигантская группа полимеров(скажем, полибутилен и ПВХ и PE и PE-X и т.д.) - это все РАЗНЫЕ органические соединения, не достаточно изученые - срок слишком мал.
Вот , например:
In this issue
Plastic pipes: Censure in Federal Health Paper
Interview: Vaillant Managing Director Manfred Ahle
Engineering history: Water for Augsburg
HYGIENE
Plastic pipes:
Unpleasant odours have to be expected
Federal Health Paper does not give a good report on various plastic products
The use of plastic pipes in sanitary engineering results in unpleasant tastes and odours. This emerges from investigations by the Hygiene Institute of the Ruhr district, Gelsenkirchen. Dr. H. Schössner and Dr. G. J. Tuschewitzki publish the results of various investigations in Federal Health Paper 7/98, under the heading -њ20 years of KTW Recommendations-ќ. As well as the pipes, the membranes in drinking water expansion tanks come off particularly badly. From the report summary: in the case of pipe manufacturers, quality assurance evidently has its gaps and must be improved. In addition, the test requirements no longer cover all health aspects and likewise require a revision.
With the very slender study basis of six types obtained on the wholesale market, it is certainly not possible to talk about a statistically substantiated condition. On the other hand, however, you can-™t assume that chance has only passed the black sheep to the inspectors. If out of six pipes, basically only a single one complies with the odour threshold value in accordance with KTW recommendations, and some of the remaining five exceed this limit 300 times, you can start to talk about a trend.
There have already been repeated complaints by consumers in the past about the unpleasant taste and odour of their drinking water. According to these, the installation engineers also carry some blame, or to phrase it more accurately, the installation engineers are first in line. Because according to the Food and Commodities Law (LMBG), both manufacturers, distributors and users, for example installation engineers, bear the responsibility for the health safety of installed commodities. And the sections of domestic drinking water installations that come into contact with drinking water are regarded as commodities for the purposes of the LMBG.
From the report
Commodities are defined by the legislator in В§ 5 LMBG as objects which are intended to be used in the manufacture, treatment, bringing into circulation or the consumption of foodstuffs and which in the process come into contact with the foodstuffs or have an influence on them. In relation to the domestic drinking water installation sector, this means: all parts of the installation coming into contact with drinking water are commodities for the purposes of the LMBG, including, for example, pipes, fittings, mountings, boilers and other containers, seals, sealants, non-hardening sealants, ion exchangers etc. According to В§ 31 LMBG, it is forbidden to use objects as commodities for the purposes of В§ 5 Para. 1 professionally or to bring them into circulation for such purposes, in such a way that substances are passed from them onto foodstuffs or their surface, excepting parts of them which are unobjectionable with regard to taste and odour, which are technically unavoidable.
The answer to the question of what is viewed as unobjectionable and technically unavoidable for the purposes of В§ 31 LMBG has been defined in the KTW recommendations by the -њDrinking Water-ќ working group of the plastics committee of the Federal Health Department. If, therefore, commodities made of plastic or other non-metal materials are manufactured that do not conform to the KTW recommendations, manufacturers and users (installation engineers) alone share the full responsibility on the basis of legal food regulations.
Naturally, this requirement applies for metal and non-metal, inorganic and organic materials. The limits of use of metal materials are predetermined, amongst other things, by the water quality, as well as the limit and standard values of the drinking water regulations. The inspection and assessment of commodities in accordance with KTW recommendations will be discussed below.
The institute assessed almost 600 different products and materials. Over the years, inspection has focused on different key points, depending on which material group or which type of commodity forms the primary interest. Thus, currently, the development of new compounds for membranes in surge tanks based on new hygienic requirements is reflected in the increased inspection of rubber compounds for the -њCategory C-ќ application range.
The relatively high overall percentage of rejected products of around 44% is based on numerous test formulas, which have sometimes only led to successful compounds after further prolonged development work.
-њNever gave a thought to the pipes in the domestic installation-ќ
On the basis of the now more than 20-year-old test procedure using the KTW test system, it can be said that this system has largely been proven. However, there are certain points which require further development. For example, when defining the limit values for pipes almost 20 years ago, these were probably not at that point intended primarily for domestic installation pipes: a pipe with a 13 mm inner diameter has a surface/volume ratio of 1:0.3. In sensory testing, according to the published test regulation, for pipes with a ratio of test body surface to test water volume of S:V=1:1, no significant taste or smell should be perceptible in the test water. It is now agreed that in pipes for domestic installation, with realistic S:V ratios the test water should also have a neutral odour, or should present an odour threshold value of 1 to 2 as a maximum. In the following, the dependence of the S:V ratios on the pipe diameter and the increase in the organic pollution of the water stagnating in the respective pipes is shown for migration rates of 2.5 mg/m2 x day (TOC migration limit value) (Table 1). The TOC migration may be 2.5 mg/m2 x day for pipe material. If the limit value is observed, theoretically a TOC concentration increase of 0.85 mg/l results for stagnant water in a 13 mm pipe. European standardisation may in future provide a differentiation according to pipe dimensions.
-њGaps in the quality control-ќ
Phenol migration was limited to 1.5 mg/m2 x day for equipment. However, with such a concentration, when combined with chlorine, the test water acquires an unpleasant taste and odour of chlorophenol, with odour threshold values of up to 400 or 500. The limit value in this case needs to be urgently checked, and a sensory test with chlorinated water generally prescribed, as planned by European standardisation, in contrast to the KTW recommendation (see pr EN 1420/1).
The materials sometimes give the test water different odours. These can come directly from the plastic, such as, for example, an odour of solvents or monomers (styrene, for example), or, as for example with putrefying odours, they can result indirectly from microorganisms. The causes of microbially induced odours need to be investigated in more detail.
The quality assurance of products on the market does not appear to be satisfactorily regulated either. Thus the investigation of a number of domestic installation materials which are common today, obtained from the wholesale trade, with the DVGW mark of conformity, only showed perfect results in one case, while five of the six inspected pipe systems produced unacceptable odours in the test water both in the cold and the hot water test, and in one case the TOC migration was also high in the cold water test (see Table 3). Even if it is not possible to claim a statistically substantiated market analysis with six arbitrarily taken samples, the results may still throw a glimmer of light on the problems discussed.
Despite extensive self-monitoring and quality control by the manufacturers, these results point to gaps in the control system and also, under some circumstances, to fluctuations in the quality of individual granulate or pipe batches. The question now arises as to whether improved quality control is required for products on the market, and whether the requirements in accordance with В§ 31 LMBG are complied with, or whether in the long-term only good quality carries through.
-њPutrefying odours from microorganisms-ќ
If one compares the study results of the cold water and the hot water test, it emerges that the odours in the test water from the hot water tests are, without exception, considerably less than those from the cold water tests. This at first glance surprising result can, however, be explained by the differing pretreatment and the different contact times in the test: For the cold water test, a 24-hour pretreatment with stagnant water at room temperature (22В°C) is prescribed, with two hours flushing and then water contact three times for 72 hours. The pretreatment for the hot water tests is 24 hours at 60В°C, the contact times with test water only three times for two hours. The relevant draft European standard prescribes an extension of the test times to three times for 24 hours for warm and hot water tests.
Table 1: Connection between pipe diameter, S:V ratio and organic pollution of the stagnant water in pipes with different nominal diameters
Table 2: Taste and odour pollution in chlorinated water through phenol migration from dishwasher hoses (chlorophenol formation)
Table 3: Results of investigation of plastic pipes for domestic installation available on the market (obtained wholesale)
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