This study analyzed borehole water quality data collected by the Water Section of the Ministry of Irrigation and Water Development since 1980s. This study was done in order to verify the rightness of the public view that borehole water is synonymous to potable water. The study analyzed water quality data of 5,324 boreholes occurring throughout Malawi. The objective of the study was to determine the extent to which borehole water salts such as: fluorides, nitrates, iron and chlorides are occurring above the concentrations recommended as safe limit of drinking water by the World Health Organization (WHO). The study observes that of the 27,913 boreholes in Malawi, only 5,324 boreholes had been tested for water quality representing about 19.1% of the total boreholes. Of these 1,676 boreholes had chemical concentration above those recommended by WHO for safe limit of drinking water, representing 31.5% of the water quality tested boreholes. The study observed that: 567 boreholes had iron, 142 boreholes had fluorides, 81 boreholes had chlorides and 19 had nitrates above those recommended by WHO for safe limits for drinking water respectively. The implication of these findings is that a large number of rural communities in Malawi are continuously ingesting borehole water that has adverse levels of chemical toxicity. The detrimental impacts on human health of such toxicity may require many years of exposure before their impacts are recognized and by that time many rural communities would already have adversely been affected.Keywords: Borehole water; chemical toxicity; rural communities; ingestio

Chimphamba, J B

Phiri, O L

English

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32J. B. Chimphamba and O.L. PhiriBorehole Water Pollution and its Implication on health on the Rural Communities of MalawiJ.B. Chimphamba1, and O.L. Phiri21 Department of Geography and Earth Sciences, Chancellor College, University of Malawi.email:  jameschimphamba@cc.ac.mw2 Regional Water Development Offices (S), Ministry of Irrigation and Water DevelopmentAbstractThis study analyzed borehole water quality data collected by the Water Section of the Ministry of Irrigation and Water Development since 1980s. This study was done in order to verify the rightness of the public view that borehole water is synonymous to potable water. The study analyzed water quality data of 5,324 boreholes occurring throughout Malawi. The objective of the study was to determine the extent to which borehole water salts such as: fluorides, nitrates, iron and chlorides are occurring above the concentrations recommended as safe limit of drinking water by the World Health Organization (WHO). The study observes that of the 27,913 boreholes in Malawi, only 5,324 boreholes had been tested for water quality representing about 19.1% of the total boreholes. Of these 1,676 boreholes had chemical concentration above those recommended by WHO for safe limit of drinking water, representing 31.5% of the water quality tested boreholes. The study observed that: 567 boreholes had iron, 142 boreholes had fluorides, 81 boreholes had chlorides and 19 had nitrates above those recommended by WHO for safe limits for drinking water respectively. The implication of these findings is that a large number of rural communities in Malawi are continuously ingesting borehole water that has adverse levels of chemical toxicity. The detrimental impacts on human health of such toxicity may require many years of exposure before their impacts are recognized and by that time many rural communities would already have adversely been affected. Key words: Borehole water, chemical toxicity, rural communities, ingestion1. IntroductionWater supply is one of the fundamental requirements for human life. The quality of water drawn by households is an important aspect of domestic supplies that influences public health (Howard and Bartram, 2003). It has been estimated that 2.6 million (37%) of Malawians use boreholes as their main source of drinking water (Pritchard, et al 2008). In Malawi boreholes are viewed as supplying potable water (Malawi Government, 1999). However a number of reports on borehole water pollution have surfaced. Ndolo (2002) reported chemical contamination of lead and hardness in shallow wells of Phalula and Balaka. Pritchard, et al (2008) observed borehole water fluoride concentration of up to 9mg/l in Kumkwawa Village in Balaka, and toxic levels of sulphates in Chikwawa and Balaka.  Sibale et al (1998) also reported high level of fluoride concentration in Machinga while Msonda et al (2007) has observed extensive fluoride toxicity in boreholes in the area of Senior Traditional Authority Mazengera around Nathanje area in Lilongwe District. The number of chemical toxicity concentration of borehole water in Malawi is increasingly becoming numerous (Msonda et al, (2007). It is the objective of this study to indicate the geochemical hazard of borehole water so as to better inform the policy and the public domain about the distribution and health risks of borehole water pollution across Malawi.MALAWI JOURNAL OF SCIENCE AND TECHNOLOGY             VOLUME 10: ISSUE 1 | 201433Borehole water pollution and its implication on health on the ....2. Materials and MethodsAnalysis of borehole water quality is an on-going process of the Water Section of the Department of Water Development in Malawi. Water quality is being analyzed in its three administrative laboratories located in the regional cities of Blantyre, Lilongwe and Mzuzu. The methods used in determination of chemical parameters are based on the Association of Official Analytical Chemists, Maryland, USA; the 17th Edition, of Association of the Official American Chemists (AOAC) and the American Public Health Association (APHA) Standard methods for the examination of water and waste water (APHA, 1989; AOAC, 1990).3. ResultsThe results of the borehole water quality data analysis has been presented in: table 1 and 2 showing borehole water pollution for districts of Malawi and the first ten districts with the highest concentration of water pollution respectively; while their spatial distribution is presented in figure 1.Table 1: Borehole water pollution for districts of MalawiDistrict Number of boreholes with chemical toxicity above the recommended safe limit for drinking water of the World Health Organization (WHO)Fluoride WHO (1.5g/l)Chlorides WHO (600g/l)Iron WHO (1mg/l)Nitrates WHO (50mg/l)Sulphates WHO (250mg/l)pH WHO (6.5-8.5)Blantyre 3 2 3 0 0 0Balaka 2 0 1 0 0 5Chinkwawa 3 12 11 2 1 3Chiradzulu 0 0 2 0 0 0Machinga 4 5 5 0 12 33Mangochi 63 19 30 1 25 195Mulanje 3 - 2 0 2 2Neno 1 - 1 0 0 1Nsanje 2 3 5 0 1 6Ntcheu 13 0 14 5 5 17Phalombe 0 0 1 1 0 0Thyolo 0 0 6 1 2 5Zomba 0 0 6 0 1 5Nkhotakota 7 0 34 1 2 28Dedza 2 0 32 4 5 96Dowa 1 0 23 1 26 23Kasungu 0 4 25 0 5 13Lilongwe 3 1 96 0 19 85Mchinji 0 1 28 0 0 13Ntchisi 0 1 19 0 2 3Salima 4 2 45 1 36 11Chitipa 0 0 3 0 0 134J. B. Chimphamba and O.L. PhiriKaronga 23 0 133 1 2 36Mzimba 1 32 24 1 3 25Nkhatabay 2 0 14 0 0 109Rumphi 2 2 4 0 1 2Likoma - - - - - -National total 139 84 567 19 150 717Total number of boreholes with contaminants is 1676Out of 5, 324 boreholes that has so far been tested for: fluorides, chlorides, iron, nitrates, chlorides, sulphates,  and pH, about 1, 676 boreholes have concentration of these salts above those recommended by the World Health Organization for safe limit of drinking water(see table 1). Mangochi District has the highest number of boreholes with fluoride and chlorides water concentration, while Karonga District of iron, Dedza District of nitrates, Salima District of sulphates and Nkhatabay District of pH (table 2). It should be noted that these numbers does not give a full picture of the rate of borehole water pollution since the number of borehole tested for water quality differs markedly between districts. On the other hand figure 1 show the spatial distribution of borehole water pollution. For each salt a symbol has been assign to indicate whether pollution level in borehole water is above WHO or above those  recommended by Ministry of Water Development for safe limit of drinking water. 35Borehole water pollution and its implication on health on the ....Chemical ParameterThe first ten highest level of concentration of borehole water contaminantsFluorides12345678910Concentration (mg/l)9.69.28.68.27.06.66.44.44.02.0Borehole NameMwambuli VillageKayuni VillageNsanamaKaluli VillageImfya VillageMtondo VillageKapote VillageMisili VillageNathenjeChimutu VillageDistrictKarongaKarongaMachingaKarongaMangochiDowaKarongaChikhwawaLilongweLiongweChlorides12345678910Concentration (mg/l)6037528351835133269020561778152212301175Borehole nameNchalo TownshipBindula VillageNyenyezi SchoolMasunduko VillageNqumayo VillageNankambaKumwenda VillageThomaBoweNkope VillageDistrictChinkhwawaMachingaMachingaMachingamzimbaMangochiMzimbaMangochiRumphiMangochiIron12345678910Concentration (mg/l)95.7876.0760.6933.527.918.617.710.59.117.25Borehole nameNgimiraNgosiMwambeloZila VillageMulwa VillageMwalalaMaganga VillageKayuniSolomoniMwandiraDistrictKarongaKarongaKarongaNkhatabayKarongaSalimaSalimaKarongaSalimaMzimbaNitrates12345678910Concentration (mg/l)52428219719612911411483.56964Borehole nameLimeyo-JereMuhiyoGumbiMpoolaKasumbuKasuloNkungulaSitoloBiwiSiliyaDistrictMzimbaPhalombeNtcheuNtcheuDedzaDedzaDedzaDedzaDedzaNtcheuSulphates12345678910Table 2: The first ten boreholes with the highest levels of concentration of water pollution 36J. B. Chimphamba and O.L. PhiriConcentration (mg/l)7,6503,9003,3703,3403,0002,9412,7081,83716761349Borehole nameUlande SchoolMotoMangumbiMbereketeChoweSosolaMduwaMandalaMalapaNqumayo VillageDistrictMangochiDedzaMangochiDowaMangochiSalimaMchinjiDowaSalimaMzimbapH12345678910Concentration (mg/l)4.44.44.55.55.89.99.568.98.88.7Borehole nameKane-kakutiMbayoCheyethuMtuwaBalaka SchoolBwanaliKajaliza               NgasaleMayeraChoweDistrictMangochiDowaNkhatabayMchinjiBalakaKasunguMzimbaMachingaMachingaMachinga37Borehole water pollution and its implication on health on the .... 38J. B. Chimphamba and O.L. Phiri4. Discussion4.1 Occurrence of borehole water pollution and its implication to healthThis study indicates that 1676 boreholes (see table 1) in Malawi have Fluorides, Nitrates, Iron, Chlorides, Sulphates and pH  above the recommended safe limit for drinking water by WHO with some boreholes having more than one of these salts. Fig. 1 has been prepared to give a preliminary picture of the geochemical hazard of borehole water pollution based on data of 5,245 boreholes that have so far been tested for water quality. The study shows that almost all the districts in Malawi have borehole water pollution of at least three salts above the recommended level for safe drinking water according to WHO recommendation. The implication for this is that a large number of rural populations are continuously ingesting water that could have negative impacts to their health. Studies have reported that Fluorides concentrations of <0.5mg/l in drinking water leads to dental carries while fluorides content of between 0.5 and 1.5 mg/l promotes dental health (WHO, 1984). Fluoride content of 1.5-4mg/l in drinking water leads to dental fluorosis while concentrations of >4mg leads to dental, skeletal and crippling fluorosis (Msonda, et al 2007; and Ndolo, 2002). Other studies have shown that the effects of fluorides could go beyond the mottling of the teeth and cause mental retardation in children (Mullenix, et al 1995). Mullenix et al (1995) further observed that fluoride accumulation in important regions of the brain, especially the hippocampus, was found to increase as the drinking water fluoride levels increased. This study observes that there are more than 139 boreholes in Malawi with fluorides concentration above 1.5g/l and up to 9.6g/l. This means that rural communities are at risk to suffering from dental fluorosis, sketletal and crippling fluorosis and mental retardation since they continuous ingest borehole water with high levels of fluorides concentration.WHO iron concentration for safe limit of drinking water is 1mg/l and has reported that the average lethal dose of iron intake is 200-250mg/l( WHO, 1996).. However, death have been reported for ingestion of iron toxicity of as low dosage as 40mg/l (Fisch et al 1975). This study observes that there are 567 boreholes with iron concentration above 1mg/l with the highest borehole having 95.6mg/l (see table 1and 2). This implies that some villages in Malawi are subjected to continuous ingestion of iron concentration that could lead to death.   On the other hand continuous ingestion of water with high nitrates concentration could also lead to death. Wilkes University , (2008) observes that drinking water with high concentration of nitrates could lead to transformation of nitrates into nitrite in the digestive system which oxidizes iron in the hemoglobin of the red blood cells to form methemoglobin. Methemoglobin lacks the oxygen-carrying ability of the hemoglobin and creates the condition known as methemoglobinemia or “blue baby syndrome” leading to death (Wilkes University, 2008). Children under the age of one year , pregnant and lactating mothers are most vulnerable to methemoglobinemia. This study observes that rural communities in Malawi are continuously ingesting borehole water from nineteen boreholes which have nitrates concentration of above 50mg/l to as high as 524mg/l. This means that children, pregnant and lactating mothers are at risk of methemoglobinemia. In conclusion this study observes that some rural communities in Malawi are continuously ingesting borehole water that is above the recommended level for safe drinking water by WHO. This situation could have long-term adverse impacts on health of such population. Malawi should therefore consider testing of water quality of all its boreholes so as to produce a comprehensive geochemical hazard database. It should also consider monitoring the impacts of continuous ingestion of such borehole water by its population and put in place policy framework that would curtail this predicament. AcknowledgementsWe are most grateful for the Malawi National Commission for UNESCO for provision of funds that enabled us to carryout this study. Our thanks also go to the Water Quality Section of the Department of Water 39Borehole water pollution and its implication on health on the ....Development for making available data on borehole water quality. We would also like to thanks Associate Professor Maurice Monjelezi of the Department of Chemistry at Chancellor College for retrieving the water quality data from access files. We would also like to thank Messrs Jonathan Gwaligwali and Makwenda Namoto both of the Department of Geography and Earth Sciences of Chancellor College for map work and compilation of the borehole water quality data. ReferencesAOAC (1990). Official Methods of Analysis, 15th Edition, Association of Official Analytical  Chemists, Arlinton.American Public Health Association (APHA), 1989. Standard Methods for examination of   water and wastewater, nineteenth ed. American Health Association (APHA), Washington Dc.Cheng Y X, IQ of children in area of high fluorine content, Chinese Journal of Control of  Endemic Diseases, Supplement 1991.Dallman. P. R., (1990). Present knowledge in nutrition, 6th ed. Washington Dc. International  Life Science InstituteFisch R. O. et al. Potential toxicity of iron overload in successive generations of rats. American  journal of clinical nutrition, 1975, 28:136-139.Howard, G., and Bartram, J. (2003). Domestic water quality service level and health. World  Health Organization. Geneva, Switzerland.Malawi Government (1999). Water Resources Management Policies and Strategies. Ministry  of water development. Lilongwe, Malawi.Mullenix, P, J., Denbesten, P, K., Schunior, A., Kernan, W, J., (1995). Neurotoxicity of sodium  fluoride in rats, Neurotoxicology Teratology, 17(2):169-177.Msonda, K, W, M., Masamba,W,R,L., Fabiano, E.( 2007).A study of fluorides groundwater   occurrence in Nathenje, Lilongwe, Malawi . Physics and Chemistry of the Earth, 32(2007) 1178-1184Ndolo, V., (2002). Examination of water availability, access and quality in drought-prone areas  in Balaka District Malawi. MSc thesis. University of Malawi, Chancellor College, ZombaPrichard, M., Mkandawire, t., O’Neill, J.G., (2008).  Groundwater Quality in Rural villages:  A case study: Malawi 2006-2007. Leads Metropolitan University, U.KSibale,F,K, Chidothi, C., Tsakala, E.,( 1998). Oral health status among the 12 and 15 year old  school pupils in Machinga District, Malawi.Wilkes University (2008). Nitrates and Nitrites in Drinking Water. Center for Environmental  Quality, Environmental Engineering and Earth Sciences.WHO 1996 (1996). Guidelines for drinking water quality: volume 2. Recommendations, 3rd  ed. World Health Organization, Geneva, Switzerland.

Borehole Water Pollution and its Implication on health on the Rural Communities of Malawi

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Borehole Water Pollution and its Implication on health on the Rural Communities of Malawi

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