Mineral element contents in drinking water - aspects on quality and potential links to human health

Mineral elements in drinking water have been in focus for more than a decade, especially as the habit of drinking bottled water has increased, not the least among young people. Minerals in drinking water have become more important since minerals in food, especially in vegetables, have decreased substantially the last decades. This thesis includes four different studies. In the first study 20 municipal raw and treated waters in southern Sweden were investigated. In the second study the concentrations of about 44 metals and ions in 33 different brands of bottled waters on the Swedish market were determined. In the third study 46 acid well waters from acid regions dominated by primary rocks of gneiss and granite were compared with 43 well waters in a district in southern Sweden situated on limestone sediments. Hair samples were obtained from all participants, who also answered a questionnaire about their self-experienced health status. In the last study the concentrations of about 30 trace elements and ions were determined in blood, urine, hair and drinking water in 38 women with defined fibromyalgia and 41 referent women, matched for age and location. The studies of well waters and municipal waters showed that water with primary rock bedrock origin had significantly lower concentrations of elements like Ca, HCO3, Mo, Se and SO4 than water from lime stone bedrock. The highest concentrations of a number of ions, e.g. Ca, HCO3, Cr, Sr, Mg and Ti were at pH 7-8 in well waters. At lower pH-values the ions probably had been leached, and at higher pH they probably were precipitated as sulphates, carbonates and hydroxides. Cu showed a concentration peak around pH 6. Fewer women drinking acid well water reported themselves as healthy compared to women drinking alkaline well water. The method for elimination of Fe and Mn from raw municipal water was efficient in all treatment plants investigated, at some plants giving concentrations in the treated water below the detection limits. Softening filters produced water with Ca-concentrations comparable to the softest waters. Adjustment of pH by the use of chemicals like lye, soda or limestone, modified the consumer water composition significantly, besides raising the pH, where limestone increased Ca and many other elements. The concentrations of potentially toxic metals such as Al, Pb and U were low. In the study of bottled waters ten of the 33 brands showed Ca concentrations below 10 mg L-1 and Mg levels below 3 mg L-1, i.e. they were very mineral poor waters. These brands were collected from areas with thin soils on primary rock bedrock. Nine of the brands were collected from limestone regions. They had high Ca-levels, with a maximum of 289 mg L-1 and Mg exceeding 90 mg L-1 in two brands. Two soft and carbonated waters were supplemented with Na2CO3 and NaCl, resulting in high concentrations of Na: 644 and 648 mg L-1 and Cl: 204 and 219 mg L-1. Storage of carbonated drinking water in Al cans seemed to increase the Al-concentration. Despite choosing referents from the same parish, the fibromyalgia women had lower concentrations of many elements and ions in drinking water compared to the referents in the fibromyalgia study. No obvious changed mineral pattern was observed in blood, water, urine or hair of women with fibromyalgia compared to referents. The daily contribution of mineral elements from different drinking waters varied substantially, depending on e.g. the bedrock situation, acidification, water treatment methods. Suitable levels of minerals elements in drinking water are suggested

Mineral Element Concentrations in Vegetables Cultivated in Acidic Compared to Alkaline Areas of South Sweden

A study in 1997, on mineral levels in acidic compared to alkaline well waters, and in women’s hair, revealed higher concentrations of a number of mineral elements like Ca, Mo and Se in alkaline waters and hair. Thus, median Ca levels were six times higher in well water and five times higher in hair from the alkaline area compared to the acidic area. This finding raised the probability of similar differences in vegetables from these areas. Thus, in the year 2006, 60 women who had participated in the study in 1997 were asked to cultivate parsley, lettuce, carrot and chive. During the spring of 2006, the women from the water and hair study of 1997, 30 of them from the acidic area and 30 women from the alkaline district cultivated vegetables: carrot (Daucus carota L), parsley (Petroselinum crispum), chive (Allium schoenoprasum) and lettuce (Eruca sativa). The vegetables were harvested, and rinsed in tap water from the kitchens of the participating women in August. The concentrations of about 35 elements and ions were determined by ICP OES and ICP-MS predominantly. In addition, soil samples from the different cultivators were also analyzed for a number of elements. Lettuce and parsley showed the highest concentrations of mineral elements per gram dry weight. Only Mo concentrations were significantly higher in all the different vegetables from the alkaline district compared to vegetables from the acidic areas. On the other hand, the concentrations of Ba, Br, Mn, Rb and Zn were higher in all the different vegetables from the acidic area. In the soil, only pH and exchangeable Ca from the alkaline area were higher than from the acidic area, while exchangeable Fe, Mn and Na concentrations were higher in soils from the acidic area. Soil elements like Al, Fe, Li, Ni, Pb, Si, Ti, V, Zn and Zr were found in higher concentrations in lettuce and parsley, which were attributed to soil particles being splashed on the plants by the rain and absorbed by the leaves. Strong correlations appeared between Ca and Sr in all the vegetables, except for carrot. No strong correlations were found between soil elements and vegetable elements, except for soil Mn and carrot/lettuce Mn. The differences in mineral levels in both, vegetables and soils were however small, compared to differences in well waters and hair. It was also suggested that the garden soils on limestone bedrock had been drained of minerals and thereby, the soil had an acidic pH. The contribution of mineral elements to daily intake in humans was considered minor from the analysed vegetables, except for some samples of lettuce that should give significant contributions of Ca, Zn, Mn and Mo. The main conclusion is that, differences in water and hair mineral levels between the two areas in the earlier study (1997) were not mirrored in vegetables cultivated in 2006. Principally, this suggests that, for humans the mineral intake of some elements from water may be more important than from vegetables

Inorganic constituents of well water in one acid and one alkaline area of south Sweden

Acid precipitation may lead to loss of essential elements and increase the concentrations of potentially toxic elements in drinking water. In this study 46 private wells from acid regions (pH < 6.5) were compared with 43 private wells from alkaline areas in southern Sweden. The concentrations of about 30 elements were analysed especially by inductively coupled plasma optical emission spectroscopy (ICP-OES). The concentrations of essential elements such as calcium, chromium, selenium and potassium were significantly lower in acid than in alkaline well water. On the other hand, the levels of potentially toxic metals such as cadmium and lead were significantly higher in acid well water. High copper concentrations, observed at pH around 6 in contrast to earlier findings, is to be considered as an acidification problem, as should the high fluoride values. The highest concentrations of a number of metals and ions, for example calcium, chromium, titanium and sulphate, appeared at pH 7.0-8.0, where the peak in concentrations occur due to leaching of metals from soil particles in acid soils and precipitation of carbonates and sulphates in more alkaline soils. The low levels of especially calcium and magnesium ions, and some micronutrients in the acid water, in combination with high concentrations of acid ions and toxic microelements, may cause nutritional imbalances. This should be regarded as risk factors with relation to effects on human health

Hair element concentrations in females in one acid and one alkaline area in southern Sweden.

Concentrations of 34 trace elements in hair have been determined in 47 females from an acid region in southern Sweden, who were compared with 43 females from an alkaline area. The concentrations of these elements in hair and drinking water were determined by inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. The hair concentrations of boron and barium were significantly higher (p < 0.001) in hair samples from the acid region, the hair levels of calcium, strontium, molybdenum, iron, and selenium were significantly higher (p < 0.001), in the alkaline region. For some metals, e.g. calcium, lead, molybdenum, and strontium, there were positive correlations between the concentrations in hair and water (r(s) = 0.34-0.57; p less than or equal to 0.001), indicating the importance of intake from minerals in water. The increased ratio of selenium/mercury concentrations in hair samples obtained in the alkaline district (p < 0.001) indicates that these subjects may have better protection against the toxic effects of mercury

Mineral Element Concentrations in Vegetables Cultivated in Acidic Compared to Alkaline Areas of South Sweden

A study in 1997, on mineral levels in acidic compared to alkaline well waters, and in women's hair, revealed higher concentrations of a number of mineral elements like Ca, Mo and Se in alkaline waters and hair. Thus, median Ca levels were six times higher in well water and five times higher in hair from the alkaline area compared to the acidic area. This finding raised the probability of similar differences in vegetables from these areas. Thus, in the year 2006, 60 women who had participated in the study in 1997 were asked to cultivate parsley, lettuce, carrot and chive. During the spring of 2006, the women from the water and hair study of 1997, 30 of them from the acidic area and 30 women from the alkaline district cultivated vegetables: carrot (Daucus carota L), parsley (Petroselinum crispum), chive (Allium schoenoprasum) and lettuce (Eruca sativa). The vegetables were harvested, and rinsed in tap water from the kitchens of the participating women in August. The concentrations of about 35 elements and ions were determined by ICP OES and ICP-MS predominantly. In addition, soil samples from the different cultivators were also analyzed for a number of elements. Lettuce and parsley showed the highest concentrations of mineral elements per gram dry weight. Only Mo concentrations were significantly higher in all the different vegetables from the alkaline district compared to vegetables from the acidic areas. On the other hand, the concentrations of Ba, Br, Mn, Rb and Zn were higher in all the different vegetables from the acidic area. In the soil, only pH and exchangeable Ca from the alkaline area were higher than from the acidic area, while exchangeable Fe, Mn and Na concentrations were higher in soils from the acidic area. Soil elements like Al, Fe, Li, Ni, Pb, Si, Ti, V, Zn and Zr were found in higher concentrations in lettuce and parsley, which were attributed to soil particles being splashed on the plants by the rain and absorbed by the leaves. Strong correlations appeared between Ca and Sr in all the vegetables, except for carrot. No strong correlations were found between soil elements and vegetable elements, except for soil Mn and carrot/lettuce Mn. The differences in mineral levels in both, vegetables and soils were however small, compared to differences in well waters and hair. It was also suggested that the garden soils on limestone bedrock had been drained of minerals and thereby, the soil had an acidic pH. The contribution of mineral elements to daily intake in humans was considered minor from the analysed vegetables, except for some samples of lettuce that should give significant contributions of Ca, Zn, Mn and Mo. The main conclusion is that, differences in water and hair mineral levels between the two areas in the earlier study (1997) were not mirrored in vegetables cultivated in 2006. Principally, this suggests that, for humans the mineral intake of some elements from water may be more important than from vegetables

Concentrations of inorganic elements in 20 municipal waters in Sweden before and after treatment - links to human health

The water chemistry of 20 municipal water treatment plants in southern Sweden, representing various bedrock situations, and water qualities, were investigated. Four water samples, raw and treated. were collected from each plant and analyzed by predominantly ICP-OES and ICP-MS at four occasions from June to December, 2001. The concentrations of Ca, Mg. K.. Na, HCO3 and a number of micronutrients, varied considerably in treated waters from the studied plants (ranges; Ca: 9.1-53.7 mg L-1, Mg: 1.4-10.9 mg L-1, K: 1.1-4.8 mg L-1, Na; 5.4-75.6 mg L-1. HCO3: 27-217 mg L-1). The elimination of Fe and Mn from raw water was efficient in all treatments investigated, giving concentrations in treated waters below the detection limits at some plants. Softening filters gave waters with Ca-concentrations comparable to the softest waters in this study. Adjustment of pH by use of chemicals like lye. soda or lime, modified the consumer water composition significantly, besides raising the pH. It was estimated that drinking water contributed to approximately 2.2-13% of the daily Ca uptake, if the gastrointestinal uptake efficiency from food and water was estimated to be around 50%. The corresponding figures for Mg was 1.0-7% and for F 0-59%. None of the studied elements showed any significant time trends in raw or treated waters during the follow-up period. The concentrations of potentially toxic metals such as Al, Pb and U were low and did not indicate risks for adverse health effects (ranges; Al: 0.5-2.3 pg L-1, Pb: 0-0.3 pg L-1, U: 0.2.5 mu g L-1)

Trace element pattern in patients with fibromyalgia

An imbalance of the trace element status in human tissues and body fluids has been suggested as a contributing factor for the development of fibromyalgia (FM). The study comprised 38 females with defined fibrornyalgia (FM) according to generally accepted criteria from the American College of Rheumatology (ACR). They were compared with 41 females matched for age and Geographic location. The concentrations of about 30 trace element and ions were determined in whole blood, urine and drinking water of all participants by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Significantly higher concentrations in whole blood of Cd, Co, Cu, Fe, Se, Sri and Zn (p <= 0.046) were observed in the FM-cases in comparison with the referents. A different pattern was noted in urine with increased urinary excretion of Ag (p=0.003) among the I'M-patients. The urinary excretion of the other elements were of the same magnitude or slightly lower in FM-cases as compared to referents. As nearly all of the concentrations of the studied elements in blood and urine were within reported reference intervals in non-occupationally exposed populations, the clinical significance of the differences observed seems to be limited. The element concentrations of the studied elements in drinking water were within present national and international guideline values (EU, WHO) and the concentrations of potentially toxic metals such as e.g. Cd, Hg and Pb were low. In conclusion, the present investigation could not demonstrate abnormal levels of trace elements in blood or urine of FM-patients and, thus, does not support the hypothesis that trace element abnormalities play a significant role in the development of FM. (C) 2007 Elsevier B.V. All rights reserved

Concentrations of inorganic elements in bottled waters on the Swedish market

This study presents the concentrations of about 50 metals and ions in 33 different brands of bottled waters on the Swedish market. Ten of the brands showed calcium (Ca) concentrations <= 10 mg L-1 and magnesium (Mg) levels < 3 mg L-1, implying very soft waters. Three of these waters had in addition low concentrations of sodium (Na; < 7 mg L-1), potassium (K; < 3 mg L-1) and bicarbonate (HCO3; <= 31 mg L-1). These brands were collected from barren districts. Nine of the brands were collected from limestone regions. They showed increased Ca-levels exceeding 50 mg L-1 with a maximum of 289 mg L-1. Corresponding Mg-levels were also raised in two brands exceeding 90 mg L-1. Two soft and carbonated waters were supplemented with Na2CO3 and NaCl, resulting in high concentrations of Na ( 644 and 648 mg L-1) and chloride (Cl; 204 and 219 mg L-1). Such waters may make a substantial contribution to the daily intake of NaCl in high water consumers. The storage of carbonated drinking water in aluminum (Al) cans increased the Al-concentration to about 70 mu g L-1. Conclusion: As there was a large variation in the material as regards concentrations of macro-elements such as Ca, Mg, Na, K and Cl. Supplementation with salts, e.g., Na2CO3, K2CO3 and NaCl, can lead to increased concentrations of Na, K and Cl, as well as decreased ratios of Ca/Na and larger ratios of Na/K. Water with high concentrations of e. g., Ca and Mg, may make a substantial contribution to the daily intake of these elements in high water consumers. Al cans are less suited for storage of carbonated waters, as the lowered pH-values may dissolve Al. The levels of potentially toxic metals in the studied brands were generally low