Nitrate in groundwater and related health risk: A case study in a village in Bachok district, Kelantan, Malaysia
Raja Adi Aiman RMM1, Shaharuddin MS1 and Zaenal Abidin2
1Department of Environmental and Occupational Health
Faculty of Medicine and Health Sciences
Universiti Putra Malaysia
2School of Health Sciences Bhakti Husada Mulia
Madiun, East Java, Indonesia
Abstract
INTRODUCTION: Nitrate pollution of groundwater is a problem especially in agricultural areas. Users who rely solely on groundwater sources are exposed to nitrate that seep from adjacent agricultural areas or septic tanks that are built very close to the water source. In Malaysia, the maximum allowable concentration of nitrate in water used for drinking is 45 mg/L (in NO3-). A study on nitrate in groundwater and its associated health risk was conducted in Bukit Bator village in Bachok district, Kelantan, Malaysia. METHODOLOGY: This study was implemented in the month of January 2019. A total of forty-two (42) respondents took part in the study with the same number of wells sampled for nitrate. Respondents were chosen based on the criteria that they only used groundwater for drinking and cooking and they do not have any type of filtration systems installed in their homes. Nitrate concentration was determined using a HANNA Instrument brand multimeter with an attached nitrate electrode. Samples were collected in duplicates and the readings were then averaged. Other data such as weight of respondents, age and depth of wells, as well as distance of well from source of nitrate were also recorded. RESULTS: Nitrate in sampled groundwater ranged from 0.61 to 25.10 mg/L NO3- with a mean of 3.61 + sd 1.88 mg/L. One-sample T Test analysis showed that there is a significant difference in nitrate concentration between sampling sites (p<0.05). In contrast, there are no significant relationships between nitrate concentration with age and depth of well, as well as distance to nitrate source (p>0.05). All respondents were calculated to have a Hazard Index (HI) of less than 1 (HI<1), meaning it is less likely for nitrate to cause adverse health effects on the users. CONCLUSION: Nitrate levels in groundwater is low and is not detrimental to health. Nevertheless, periodic assessment is encouraged to ensure the levels stay low at all times.
Keywords: Nitrate, groundwater, Hazard Index, Kelantan, levels
Topic: Environmental and Occupational Health