Drinking Water of Different Hardness Compared to the Entire Population of the Slovak Republic (SR)

LIFE Project Number LIFE 17 ENV/SK/000036 Acronym: LIFE – WATER and HEALTH

SHORT REPORT

Characteristics of health status in municipalities with different types of water hardness.

(Summary. The full text of the report is in attachment)

(Activity B.1: Risk Analysis)

05/11/2019

Anna Letkovičová, Stanislav Rapant, Viktor Kosmovský, Veronika Cvečková, Juraj Macek

Abstract The report appreciates the health status and demographic trend of two groups of municipalities supplied with drinking water of different hardness compared to the entire population of the Slovak Republic (SR). The aim was to determine if there are differences in health status depending on the different hardness of drinking water. The health status of 1994 - 2008 (15 years) was evaluated. The data originate from the registers of the Statistical Office of the Slovak Republic and are therefore guaranteed by the state. The first group of municipalities that is supplied with "soft" drinking water (Ca - 20.7 mg l-1, Mg - 6.05 mg l-1, (Ca Mg) - 0.77 mmol l-1) consisted of 34 municipalities and 52,676 inhabitants in total. The second group of municipalities that is supplied with "hard" drinking water (Ca-70.1 mg l-1, Mg-26.4 mg l-1, (Ca Mg) - 2.88 mmol l-1) consisted of 21 municipalities and 53,118 inhabitants lived there. As reference group, 2,762 municipalities of the SR (99.87% of the population) were used. Municipalities under 100 inhabitants that give unreliable results in health indicators were excluded from all municipalities of the Slovak Republic. The selected municipalities in both groups were similar in number and each group represented approximately 1% of the Slovak population. The health status of the population in both groups was monitored with using 96 health indicators (HI) divided by age

and sex. We present the results of the 13 most important health indicators including life expectancy, crude mortality, premature death rate, years of life lost and relative and indirectly standardized mortality for four main causes of death in Slovakia; namely cardiovascular system, malignant tumors, digestive and respiratory systems. All examined and evaluated health indicators exhibited statistically significantly better values in the group of municipalities with “hard” water. No single health indicator was found that would be better in a group of municipalities with “soft” water. In comparison with the whole territory of the Slovak Republic is the result the same. The group of municipalities with “hard” water exhibits all health indicators better than the average of the Slovak Republic and the group of municipalities with “soft” water has all health indicators worse comparing the average of the Slovak Republic. The group of municipalities with “soft” drinking water has absolute deaths as well as species-specific and relativized deaths more than 50% higher (i.e. worse) than the group of municipalities with “hard” drinking water. Contrary, the life expectancy is better in the group of municipalities with “hard” water in all age categories. People live statistically demonstrably longer. When averaging all used health indicators are the health indicators in the group of municipalities with “soft” water 62% higher, consequently worse than in a group of municipalities with "hard" water. Neither of indicators is lower (i.e. better). Besides the life expectancy that is 4.5 years higher in the group of municipalities with “hard” water.

INTRODUCTION The aim of this activity was to confirm the current knowledge that the health status of people supplied with drinking water with higher hardness (for simplification in the following we use the term "hard" water) is better than the health status of people who are supplied with drinking water of lower hardness (soft” water). E.g. in Yang et al. (1998), Catling et al. (2005), Runenowitz-Lundin a Hiscok (2005), Selinus et al. (2005), Rosborg I. ed. (2015), Rapant et al. (2017), Koppová et al. (2017). According to the project, two groups of municipalities were random selected, which are supplied with drinking water of different hardness, namely those with more than 50,000 inhabitants in each group of municipalities, as established in the project. A total of 96 health indicators were compiled for both groups of municipalities, divided according to the age and sex. For comparison we used the whole population of the Slovak Republic from which municipalities under 100 inhabitants were excluded. The final assessment of the health status of both groups of municipalities included 13 most important HIs including expected life expectancy, crude mortality, percentage of premature deaths, years of life lost and relative indirect-age standardized mortality for the four main causes of death in Slovakia – cardiovascular system, malignant tumors, digestive and respiratory systems. All results in the health status differences of the two population groups were subjected to statistical analysis – T-test, ANOVA and Kolmogorov-Smirnov test by Statgraphic system.

SELECTION OF MUNICIPALITIES As mentioned in terms of the project we have selected two groups of municipalities. Each group includes at least 50,000 inhabitants. We chose them based on the chemical composition of the water. The first group of municipalities, (in following referred as 'soft' water), consisted of municipalities supplied with drinking water with a low Ca content of approximately 30 mg l-1 and less, Mg approximately 10 mg l-1and below and a low total water hardness of about 1 mmol l-1 and less. The second group of municipalities (referred as “hard” water) consisted of municipalities with a higher to high Ca content of approximately 50 mg l-1and more, Mg approximately 25 mg l-1 and more and the total water hardness value is about 2.5 mmol l-1and more. We have selected municipalities with at least 500 inhabitants. The only exception was the village Devičie with 302 inhabitants. This municipality was included in the group of “soft” water because of the fact that there will be drinking water recarbonized. The population numbers were selected not random. From previous work (e.g. Rapant et al, 2010; Fajčíková et al., 2016) it is obvious that small municipalities under 500 inhabitants often show unbalanced health indicators due to a small number of inhabitants (small number error). On the other hand, large municipalities (towns) with more than 10,000 inhabitants are often supplied with various drinking water from several sources. We also want to avoid the fact that if we selected 4 - 5 municipalities with 10,000 inhabitants and more, we would not be able to obtain the necessary variability of health indicators. Inhabitants of municipalities ranging from 500 to 5,000 of inhabitants show the most balanced indicators in health indicators and are most closely related to the environment (Rapant et al., 2010; Fajčíková et al., 2016). Therefore we have chosen the municipalities as described. In the case of a group of municipalities of “soft” water due to the fact that these (drinking) groundwater originate from a low water-saturated silicate geological basement with low water yield, we had to select more municipalities into this group. Municipalities with several thousand inhabitants supplied with soft drinking water occur in Slovakia only in a very limited number. Overview of the basic chemical parameters of water for the group of municipalities “soft“ water is shown in Tab. 1 and for the group of municipalities 'hard' water in Tab. 2. In Fig. 1 is presented the HI distribution of individual municipalities.

Table 1 Basic chemical parameters for municipalities group „soft“ water.

Number of the Conductivity Ca Mg (Ca + Mg) Municipality District Geology pH population [µS cm-1] [mg l-1] [mg l-1] [mmol l-1] Hiadeľ Banská Bystrica 3 515 7.60 315.00 33.00 15.70 1.47 Šumiac 2 1,334 7.74 86.00 11.00 2.50 0.38 Braväcovo 2 703 6.52 116.00 11.40 2.90 0.40 Bacúch 2 995 7.14 50.00 7.60 2.00 0.27 Pohorelá Brezno 2 2,332 7.96 62.00 8.10 2.30 0.30 Jasenie 2 1,188 7.74 186.00 30.20 5.90 1.00 Hronec 2 1,192 7.83 338.00 40.00 16.80 1.69 Čierny Balog 2 5,214 7.11 97.00 11.00 2.30 0.37 Látky 2 578 6.80 190.30 8.90 2.20 0.31 Detvianska Huta 2 708 6.11 53.80 5.40 3.00 0.26 Podkriváň Detva 2 599 8.34 170.00 21.60 4.40 0.72 Stožok 6 952 7.36 150.00 13.00 4.10 0.49 Vígľaš 6 1,697 8.19 167.00 24.70 3.00 0.74 Litava 6 767 7.31 230.00 21.50 7.40 0.84 Krupina 6 8,007 7.20 185.00 21.60 7.70 0.86 Litava Krupina 6 767 7.31 250.00 21.50 7.40 0.84 Cerovo 6 603 7.37 185.00 26.40 11.60 1.14 Devičie 6 302 7.01 280.00 30.00 10.2 1.15 Pukanec Levice 6 1,984 7.59 380.00 48.90 9.24 1.60 Prochot Žiar n/Hronom 6 595 7.30 150.00 12.40 6.90 0.59 Dobroč 2 643 8.31 154.00 30.30 4.00 0.92 Divín Lučenec 2 2,061 8.36 150.00 19.50 6.20 0.74 Rapovce 8 978 8.85 117.00 18.20 5.40 0.68 Kokava nad 2 3,000 8.00 140.00 19.10 3.50 0.62 Rimavicou Kalinovo Poltár 8 2,229 8.60 126.00 17.60 2.00 0.52 Poltár 8 5,754 8.76 165.00 29.10 2.00 0.81 Utekáč 2 1,027 7.10 112.00 15.90 2.02 0.70 Rudník Košice – okolie 1 631 7.16 186.00 17.80 7.70 0.76 Rakovec nad 6 1,085 7.52 189.00 37.00 2.90 1.04 Ondavou Michalovce Poruba pod 6 627 7.28 178.00 24.80 4.50 0.80 Vihorlatom Čierna Lehota Rožňava 2 617 6.50 113.00 19.70 3.90 0.65 Kluknava 1 1,623 8.03 220.00 20.60 7.20 0.81 Kojšov 1 741 7.40 215.00 20.80 8.10 0.85 Mníšek nad Hnilcom Gelnica 1 1,717 7.20 198.00 21.20 6.50 0.80 Žakarovce 1 724 7.72 205.00 25.80 5.20 0.86 Smolník 1 1,183 7.60 100.00 14.20 3.50 0.50 arithmetic average 7.55 172.48 21.20 5.66 0.77 SLOVAC REPUBLIC 7.33 93.56 28.29 3.50 Note 1 – Paleozoic, metasediments, metavolcanites; 2 – Crystalline, granitoids and crystalline schists; 3 – Mesozoic carbonates and basal Paleogene sediments, limestones, dolomites, conglomerates; 6 – neovolcanites, andesites, basalts and pyroclastics; 8 – Qauternery, gravels, sands, loams, rock clasts; Number of the population for “soft” water 52,676 (31. 12. 2018 ), Number of the population in Slovak republic 5.5 mil.

Table 2 Basic chemical parameters for municipalities group „hard“ water. Number of the Conductivity Ca Mg (Ca + Mg) Municipality District Geology pH population [µS cm-1] [mg l-1] [mg l-1] [mmol l-1] Nižná 5 4,024 7.71 426.30 63.40 14.33 2.17 Suchá Hora Tvrdošín 5 1,386 7.80 396.50 55.09 16.60 2.06 Podbiel 5 1,268 7.59 315.00 42.30 12.80 1.58 Bobrov Námestovo 5 1,685 7.92 318.00 42.80 12.60 1.59 Nové mesto Bošáca 5 1,384 7.43 568.00 78.00 35.60 3.41 na/Váhom Kanianka 8 4,125 7.94 522.00 86.60 33.10 3.52 Lazany Prievidza 8 1,600 7.90 515.00 60.90 27.20 2.64 Dolné Vestenice 3 2,575 7.33 598.00 88.10 27.60 3.33 Trenčianska Turná 8 3,133 7.44 429.50 62.40 23.70 2.54 Trenčianska Teplá Trenčín 3 4,140 7.48 636.80 91.40 38.00 3.84 Dolná Súča 5 2,996 7.44 660.70 88.20 34.00 3.60 Dudince Krupina 7 1,453 7.45 620.00 96.80 21.30 3.29 Nenince Veľký Krtíš 8 1,394 6.96 996.00 82.60 37.50 3.60 Spišská Teplica Poprad 3 2,236 7.55 551.00 73.70 31.10 3.12 Svidník Svidník 5 11,289 7.91 381.00 60.18 21.50 2.38 Gerlachov 5 1,042 7.85 461.00 78.60 19.00 2.74 Bardejov Malcov 5 1,572 8.15 400.70 38.50 28.20 2.12 Torysa 5 1,522 8.13 629.00 80.40 36.80 3.52 Sabinov Dubovica 5 1,479 7.84 763.50 76.20 35.60 3.37 Chminianska Nová 5 1,304 7.94 571.20 63.50 28.40 2.75 Ves Prešov Župčany 5 1,511 7.63 631.00 62.80 20.10 2.39 arithmetic average 7.69 542.39 70.12 26.43 2.84 SLOVAC REPUBLIC 7.33 93.56 28.29 3.50 Note: 3 – Mesozoic carbonates and basal Paleogene sediments, limestones, dolomites, conglomerates; 5 – Flysch Paleogene, sandstones, schists, clay shales; 7 – Neogene sediments; 8 – Quaternary, gravels, sands, loams, rock clasts; Number of the population for “hard” water 53,118 (31. 12. 2018 ), Number of the population in Slovak republic 5.5 mil.

Fig. 1

From the above presented tables it is evident that there are fundamental differences in the content of Ca, Mg and water hardness in both groups of municipalities. For a group of municipalities 'soft' water, the average Ca content is 21.20 mg l-1, Mg 5.66 mg l-1 and (Ca + Mg) 0.77 mmol l-1. In the group of municipalities “hard” water are these values almost four times higher, for Ca 70.12 mg l-1, Mg 20.10 mg l-1 and (Ca + Mg) 2.39 mg l-1. The average water hardness content and the Ca and Mg content for both groups of municipalities are presented in Tab. 3, together with the normative values of the Slovak standard for drinking water (Decree of the Ministry of Health of the SR No. 247/2017 Coll.). From the data presented in Tab. 5 it is clear that the Ca, Mg content and water hardness are approximately four times lower in the 'soft' water group than in the 'hard' water group.

Table 3 Average content of Ca, Mg and water hardness in evaluated groups of municipalities in comparison with limit values for Slovak standard for drinking water. Parameter Standard value* „Soft“ water „Hard“ water Ca [mg l-1] > 30 20.7 70.12 Mg [mg l-1] > 10 6.05 26.4 (Ca + Mg) [mmol l-1] 1.1 – 5.0 0.77 2.84

Note: * recommended value of the Decree of the Ministry of Health of the Slovak Republic no. 247/2017 Coll.

CHARACTERISTICS OF HEALTH STATUS OF INHABITANTS IN SELECTED TWO GROUPS OF MUNICIPALITIES Characteristics of health status of inhabitants of two selected groups of municipalities we present according to so- called health indicators - indicators of health status and population demographic development. We used the data from the Statistical Office of the Slovak Republic and evaluate the period 1994 - 2008. All data represent 15-year averages. All health indicators were compiled on the basis of the International Disease Catalogue, the 10th revision (www.nczisk.sk) and were compiled according to the WHO recommendations (e.g. Jeníček, 1995, Bencko et al., 2003a, b). All health indicators used are robust, stable, easy to construct and internationally comparable. Each health indicator was compiled according to gender, men, women and population together. We also approached the age differentiation of each health indicator. A total of 96 health indicators were compiled, of which the following are the most important 13 health indicators listed in Tab. 4. All health indicators in both groups of municipalities are compared among each other and against the average value of the Slovak Republic. Municipalities with less than 100 inhabitants were not included in the Slovak average. Overall, the Slovak average represents the average of 2,762 municipalities (5.39 million of inhabitants) and represents 99.87% of the Slovak Republic population. The group of municipalities “soft” water represented 52,676 inhabitants and the group of municipalities “hard” water represented 53,118 inhabitants. The group of municipalities “hard” water thus represented 1.03 times the population of the group “soft” water. The basic characteristics of the health status of the population of both water groups are shown in Table 5.

Table 4 Basic characteristics of used health indicators

No. HI HI description Unit Note 1 LE Life time expectancy years Basic cross-section indicator 2 CM Crude mortality coefficient Basic orientation in mortality 3 ReC coefficient Malignant neoplasm C00-C97 4 ReI Relative mortality per 100,000 inhabitants for coefficient Diseases of the circulatory system I00-I99 5 ReJ the chosen cause (a group of causes) coefficient Diseases of respiratory system J00-J99 6 ReK coefficient Diseases of the digestive system K00-K93 7 SMR % against SR All deaths without choice 8 SMRC Indirect age-standardized mortality rate of % against SR Malignant neoplasm C00-C97 inhabitants related to selected cause; 9 SMRI % against SR Diseases of the circulatory system I00-I99 percentage comparison to the Slovak 10 SMRJ republic as standard % against SR Diseases of respiratory system J00-J99 11 SMRK % against SR Diseases of the digestive system K00-K93 12 PD Premature death % from all Whatever the cause 13 PYLL Potential years of lost life years Whatever the cause

Table 5 Basic characteristics of health status of inhabitants of both water groups.

Data for 1994 – 2008 Municipalities Municipalities Slovak Republic (SUM) „soft“ water „hard“ water

Number of municipalities in the group 2,762 34 21

Number of persons years 80,799,554 804,450 776,959 Number of deaths 785,328 10,740 5,796 Number of premature deaths 225,518 3,167 1,521 Number of PYLL 3,184,312 46,417 21,527 Number of cancer deaths 172,995 2,099 1,249

Number of deaths due to 429,239 6,125 3,315 cardiovascular causes Number of deaths due to respiratory 46,435 704 307 diseases Number of deaths from digestive 38,994 557 235 diseases

As there are practically equal groups of municipalities, the input data should be the same for both groups of municipalities (more precisely 1.03 times higher in the group of municipalities “hard” water). However, a fundamental difference is evident from Tab. 5. All health indicators in the group of municipalities “soft” water are almost two times higher, i.e. more unfavorable compared to the group of municipalities “hard” water. In more detail are the individual health indicators introduced in Tab. 6. Table 6 illustrates even more clearly the differences in health status of the inhabitants of two selected groups of municipalities. For example the life expectancy in the “soft” water group is 4.58 years lower than in the “hard” water group of municipalities. The main cause of death in Slovakia - cardiovascular diseases (about 50% of all deaths) is up to 56% higher in the group of municipalities with “soft” water. Similarly in the case of the second

most common cause of death - cancer (about 25%), the difference is almost 62%. The largest differences in relative mortality were observed in the digestive and respiratory system, more than 100%. The group of municipalities “soft” water is worse in all observed health indicators than the national average and the group of municipalities “hard” water is better than the national average. This is also evident from Fig. 2. Table 6 Characteristics of 13 basic health indicators. Slovak republic HI „Hard“ water „Soft“ water No. HI description (2,933 Abbr. (21 municipalities) (34 municipalities) municipalities) 1 LE Life expectancy at birth 72.65 74.58 70.00 2 CM Crude mortality 9.72 7.47 13.35 3 ReC 214.10 160.92 260.92 4 ReI Relative mortality for selected cause of 531.24 427.10 761.39 5 ReJ death 57.47 39.55 87.51 6 ReK 48.26 30.28 69.24 7 SMR 100.00 87.82 114.49 8 SMRC Indirect age-standardized mortality rate of 100.00 83.53 104.77 9 SMRI inhabitants to the Slovak standard (19 age 100.00 95.55 116.58 10 SMRJ groups) 100.00 80.85 120.75 11 SMRK 100.00 87.82 114.49 12 PD Premature death 28.82 27.15 29.95 13 PYLL Potential years of lost life 3,941.00 2,773.53 5,770.03

Fig. 2: Illustration of the difference in health indicators of selected groups of municipalities in comparison with Slovak Republic.

As next we have statistically tested the statistical significance of the differences in health indicators in both groups of water. According to the Kolomogorov-Smirnova test (Tab. 7), all the above mentioned differences in the evaluated health indicators of the two allocated groups of municipalities are very high statistically significant and only in the case of the PD indicator confirmed the verified statistical significance more than 95%. When we have averaged all 13 assessed health indicators, the health indicators in the group of municipalities "hard" water are in average 62% better than in the group of municipalities "soft" water.

Table 7 Results of statistical significance testing of selected water groups. No. HI HI description „p“ value Interpretation 1 LE Life time expectancy at birth 0 +++ 2 CM Crude mortality 0.0000001 +++ 3 ReC 0 +++ Relative mortality per 100,000 4 ReI 0 +++ inhabitants per selected cause 5 ReJ 0.0000481 +++ (group of causes) Very high statistically significant difference 6 ReK 0.0000004 +++ 7 SMR 0 +++ 8 SMRC Indirect age-standardized 0.000124 +++ 9 SMRI mortality rate of inhabitants to the 0.000109 +++ 10 SMRJ Slovak standard (100%) 0.000433 +++ 11 SMRK 0.0003375 +++ 12 PD Premature death 0.0132 + Statistically verified dependency 13 PYLL Potential years of lost life 0 +++ Very highly statistically significant difference Note: p-value – approximate significance level,, p < 0.05 – proved dependence (+)], p < 0.01 – high dependence (++), p < 0.001 – very high dependence (+++).

CONCLUSION In all cases, the inhabitants of municipalities supplied with “soft” drinking water have significantly worse health and demographic indicators than the inhabitants of municipalities supplied with “hard” drinking water by up to 62%. The group of municipalities with "soft" drinking water is worse in all health indicators with high statistical evidence than the group of municipalities with "hard" drinking water. If we consider the individual death causes, the highest differences are observed in the case of diagnosis I21 - acute myocardial infarction - 3.23 times more in the group of municipalities „soft“ water, diagnosis I25 - chronic ischemic heart disease - 2.17 times more in the group municipalities "soft" water and diagnosis C34 - bronchial and lung malignancy - 2.17 more in the “soft” water group than in the 'hard' water group. As the highest and most noticeable difference note is the number of deaths from the diagnosis of G80 - child brain paralysis. In the case of the group of municipalities “hard” water, two cases were recorded during the 15 evaluated years and in the group of municipalities “soft” water up to 34 cases. Generally have the group of municipalities with “soft” water all health indicators relatively high inhomogeneous with many outlying to extreme values. The group of municipalities with “hard” water is similar in health indicators and there are no extraordinary extreme values in this group of municipalities. A total of 14 municipalities of the 34

municipalities supplied with “soft” drinking water recorded extreme values of some health indicators also in the whole of Slovak Republic. In the case of municipalities supplied with “hard” water, no extreme municipality was registered. The results of this activity thus confirmed a significant deterioration in the health of the population supplied with “soft” drinking water. In the case of cardiovascular and oncological diseases, a similar situation has been observed in many countries around the world. Our results suggest that the deficient content of Ca and Mg in drinking water significantly contributes to increased mortality as well as to the digestive and respiratory systems, even more pronounced than for cardiovascular and oncological diseases. Literary data on increased digestive and respiratory system mortality associated with hardness of drinking water are unknown. Deficient content of Ca, Mg, and the hardness of drinking water has generally a negative effect on human health. However, this deficit does not seem to affect every individual and all people equally. Perhaps more sensitive individuals are more affected to the resistant ones. This is evidenced by the much higher incidence of extreme values of health indicators within the “soft” water group of municipalities. Based on the results shown in this work we believe that the values of the Ca and Mg content in drinking water greatly affect the health status of people and should therefore be limited in WHO drinking water standards.

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