UK,DRINKING WATER

UK,DRINKING WATER INSPECTORATE EUROPEAN COMMUNITY EUROPEAN UNION UK WESTERN EUROPE... 

Regulatory FDA 21CFR 176.170,176.180 BGACh. 36 UK Drinking Water Inspectorate approved... 

The use of chlorine dioxide in water systems results in its reduction to chlorite and chloride. In the UK the Drinking Water Inspectorate (DWI) restricts the use of chlorine dioxide in potable water supplies to a maximum of 0.5ppm total oxidants expressed as chlorine dioxide. This ensures that chlorite (and any chlorate) concentrations do not reach levels of potential harm to humans. 

Fielding W, Gibson TM, James HA, McLoughlin K, Steep CP (1981) Organic micropollutants in drinking water. Technical report TR 159. Water Research Centre, Medmenham, UK... 

Compound name Chemical group Current UK usage (tonnes/a) Rate of application (kg/ha) Water solubility (mg/l) Physical class Pollution hazard class " Drink water guideline (PgH)... 

Chapter 5 of the document reviews the UFs used by UK Government departments, agencies, and their advisory committees in human health risk assessment. Default values for UFs are provided in Table 3 in the UK document with the factors separated into four classes (1) animal-to-human factor, (2) human variability factor, (3) quality or quantity of data factor, and (4) severity of effect factor. The following chemical sectors are addressed food additives and contaminants, pesticides and biocides, air pollutants, drinking water contaminants, soil contaminants, consumer products and cosmetics, veterinary products, human medicines, medical devices, and industrial chemicals. 

DWI (Drinking Water Inspectorate) (1993), Further guidance on analytical systems (Department of the Environment London), Available http // www.dwi.gov.uk/regs/infolett/1993/info893.htm. 

In the early part of2004 there was a problem in the UK caused by low levels ofbromate in a branded bottled water. This arose from the presence of low levels of bromide in the water that was then disinfected by treatment with ozone. The bromate ions formed were at levels above the EU and EPA limit of lOpg/l for drinking water. The analysis of this anion at trace levels is demanding and should be left to a specialist laboratory. However, Dionex have published four methods that can be used for the analysis of bromate ions in water and the application notes (81, 101, 136 149) are available from the Dionex website (http /www. dionex. com/)... 

Fluoridated drinking water is currently available to only 12% of the UK population, a figure unlikely to grow due to strong opposition from pressure groups opposed to mass medication. Fluoride protects teeth in four ways (Shellis and Duckworth, 1994) ... 

The exposure to lead in food by the general population in the UK is well within international tolerable limits. Results from the TDS indicate that during the period 1976 to 1997 the dietary exposures over the whole population fell from 0.11 to 0.026 mg per person/day (Table 7.1).6 This excludes any contribution from drinking water, which is likely to be higher in areas with soft water. The PTWI recommended by JECFA is 0.025 mg/kg bodyweight, equivalent to 0.21 mg/day for a 60 kg adult. The dietary exposures for mean and 97.5th percentile consumers in 1997 were 0.024 mg/day and 0.043 mg/day respectively, well below the PTWI. These dietary exposures to lead in the UK are similar to those in Canada (0.024 mg/day),7 The Netherlands (0.01 to 0.032 mg/day),8 and the USA (0.015 mg/day).9... 

Although dietary lead intakes in the UK are currently well within recommended intakes, it is the UK Government s policy to ensure that exposure to lead is reduced wherever practicable and, more specifically, to reduce blood lead levels in children to below 10 pg/dl. Food is one of the major sources of lead exposure in the UK the others are air (mainly lead dust originating from petrol) and drinking water. Exposure from all of these sources has been reduced, as demonstrated by the reduction in blood levels over the past 15 years.10 The decrease in dietary exposure reflects the success of the measures taken to reduce lead exposure and contamination of food, such as the use of lead-free petrol, welded food cans, and the banning of tin-coated lead capsules for wine bottles. 

S. Hillier, C. Cooper, S. Kellingray, G. Russell, H. Hughes, D. Coggon, Fluoride in drinking water and risk of hip fracture in the UK a case-control study, The Lancet 335 (2000) 265-269. 

Bergmann, M.E.H., Rollin, J., Koparal, A.S. and Kresse, K. (2006b) What is the ominous chlorine consumption in the disinfectant production from drinking water electrolysis Proceedings 57th Annual Meeting of the International Society of Electrochemistry, 27 Aug. to 1 Sept., Edin-burgh/UK, p. S5.0-4. 

The use of weedkillers has also been on the increase over the last 20 to 30 years. Although it is difficult to prove specifically which chemicals may be carcinogenic, there are increased levels of herbicidal residues in drinking water and concerns over many of the synthetic substances being used. Every year, governments in various countries withdraw from use chemicals that have previously been used on our food supply when proof of their toxicity is established. The classic example is DDT, which was used as an insecticide from 1939. Over a period of 50 years almost five billion pounds of it have been used across the world. It became prohibited in the US in the 1970s and in the UK in 1984 because of links to deaths, cancer, allergies, infertility, problems in fetal development and major diseases of the immune system. 

One practical use of Fenton and photo-Fenton processes is the removal of natural organic matter (NOM) from organic rich waters before the chlorine disinfection of drinking water. It was observed that, under optimal conditions, both processes achieved more than 90% TOC removal, leading to the potential formation of trihalomethanes at concentrations below 10 ig IT1, well under UK and US standards [78]. 

A new UK standard reducing the lead level in drinking water by 2003 (264) was an additional factor. 

List of Approved Products and Processes, Department for Environment, Food and Rural Affairs, Drinking Water Inspectorate, DWI, London, UK, 2003. 

The above calculations estimate that for a typical adult in a developed country, daily uptake of lead from air, diet, and drinking water is, respectively 1.4 pg, 6 pg, and 1.1 pg. Exposure to lead from all of these sources has fallen rapidly over the past 20-30 years. Figure 12 contrasts the temporal trends in use of lead in petrol (gasoline) and blood leads in the general population of the UK over the period when much of this decline took place. It is interesting to note that from 1971 to 1985 use of lead in petrol was relatively steady, but blood leads declined by a factor of more than two over this period mainly as a response to reductions in dietary exposure, particularly associated with the cessation of use of... 

The oestrogen ethynyloestradiol is, as we saw earlier, known to be present in sewage treatment plant effluents and could potentially appear in drinking water. It has apparently been detected in drinking water in the UK but the data have been questioned. Even if it were present, it is not known whether the concentrations would be high enough to affect human males. 

Both acute and chronic exposure to lead became more common with the advent of the Industrial Revolution and there were as many as a thousand cases per year of lead poisoning in the UK at the end of the nineteenth century. During the nineteenth century there were also many cases of lead poisoning due to contamination of domestic drinking water in areas such as the north of England where slightly acidic water was delivered to houses in lead pipes. Lead was also used in fungicides in the form of lead arsenate. 

Fig. 5.13 Mean annual dissolved nitrate concentrations in the River Thames, UK, 1930-1980. WHO limit refers to the World Health Organization recommended maximum safe nitrate concentration in drinking water. Data courtesy of UK Department of the Environment National Water Council, Crown Copyright 1984.

Kemp KH and Weatherell A (1975). The subjective detection of CR contamination in drinking water. CDE Technical Note, Number 238, dated June 1975. Porton Down, Salisbury, UK Ministry of Defence, Chemical Defence Establishment. 

In Europe, some studies have been carried out to check the presence of MTBE in drinking water and corresponding sources. In the UK, Dottritge et al. [51] reported detectable concentrations (> 0.1 pgL ) at 13% of studied locations. However, MTBE levels were predominantly low (< 1 p,g ) and the study concluded that the presence of less than 1% MTBE (v/v) on average in British gasohne was not a major threat to pubhc water supphes in England and Wales. 

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