PUBLIC HEALTH RISK ASSESSMENT FROM HEAVY METAL POLLUTION IN THE ENVIRONMENT OF UPPER CITARUM RIVER WATERSHED

• Main Author: Fahimah, Nurul
• Format: Dissertations
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/81040
• Institution: Institut Teknologi Bandung

Heavy metals are one of the pollutants that are toxic, non-biodegradable, and persistent. The use of water contaminated with heavy metals can pose health risks. The research aims to analyze Chemicals of Potential Concerns (COPCs) from 10 types of heavy metals, assess health risks, evaluate Disability-Adjusted Life Years (DALYs) from one type of heavy metal estimated to be most risky to health, and analyze the potential sources and validation of risk levels on exposure biomarkers (urine, toenail, and blood) and effect biomarkers (DNA damage [8-OHdG]). This research was conducted from 2021 to 2023 in 7 districts, namely Baleendah, Majalaya, Rancaekek, Ciparay Soreang, Pacet, and Pangalengan. A total of 184 groundwater samples, 96 soil samples, and 98 other drinking water samples were collected. There were 416 respondents involved to obtain anthropometric data, length of stay, drinking water consumption rate, habit patterns, and others. In the validation of health risk assessment, 13 individuals were involved as respondents in the unexposed arsenic group, 17 as exposed arsenic group, 9 as skin cancer cases, and 10 as controls for skin cancer cases (unexposed to arsenic and not suffering from skin cancer). The heavy metal content of water and soil samples was analyzed using ICP – OES, and biological samples using ICP-MS. The level of 8- OHdG was measured with ELISA Kit. Health risk assessment followed the steps of the US EPA. All data were processed with Microsoft Excel, ArcGIS 10.8, and IBM SPSS Statistics. This study found 6 types of heavy metals categorized as COPCs, namely arsenic, cadmium, cobalt, mercury, manganese, and lead. Exposure to COPCs heavy metals in groundwater through dermal absorption pathways did not show noncarcinogenic and carcinogenic effects, however, arsenic and lead exposure through ingestion pathways showed non-carcinogenic (HI >1) and carcinogenic effects (ILCR > 1 x 10-4 ). Among various types of drinking water, the non-carcinogenic and carcinogenic risk level values varied, namely: bottled water > groundwater > rainwater > springs. Arsenic contributes significantly to the total carcinogenic risk, which is 99.84% for males and 99.55% for females, thus arsenic is concluded as the heavy metal found most risky to public health. Arsenic in drinking water is estimated to pose non-carcinogenic health risks, namely skin lesions (HI >1). In lifelong exposure, arsenic in drinking water is estimated to pose a risk of skin cancer, namely 4.94 per 10,000 population for adult females and 5.14 per 10,000 population, exceeding the safe limit of 1 per 10,000 population. Arsenic exposure can cause health losses as estimated to reduce healthy life years (DALYs) of the community, by 18.36 years (8.38 – 28.79 years), or the lost DALYs rate is 2.3 per 100,000 person-years and 23.02 times higher than the WHO reference risk rate. Principal Component Analysis results show that manganese and arsenic are suspected to originate from natural sources (leaching from geological formations), while mercury, lead, and cadmium are suspected to originate from human activities. There is an indication that cobalt is not only from natural sources but also from human activities. Arsenic, which is the heavy metal most risky to public health, is significantly associated with well depth, where deeper wells tend to have higher arsenic content (p < 0.01). The use of bore wells increases the risk of arsenic contamination by 2.299 times compared to dug wells. The release of arsenic from geological formations is suspected to be accelerated by geothermal system activities, as evidenced by higher arsenic concentrations in areas near geothermal systems (5-10 km), with concentration ratios up to 45 times higher than in areas far (>10 km) from geothermal systems. Fault lines or faults are also suspected to be transport routes for arsenic, with arsenic concentrations in soil 3.828 times higher in areas close to fault lines or faults. Additionally, this research found that arsenic in soil is also suspected to originate from human activities such as agriculture and industry. The variation pattern of arsenic in soil in agricultural areas is at the subsoil depth (50 – 60 cm) > topsoil (10 – 20 cm) > deep soil (90 – 100 cm), while in residential soils, it is subsoil > deep soil > topsoil. Arsenic concentrations in soils within <2 km from industrial areas follow the sequence of topsoil > subsoil > deep soil, whereas at locations more than or equal to 2 km away, the sequence of arsenic concentration in soil is found to be subsoil > deep soil > topsoil. The validation of health risk assessment was conducted on respondents who used groundwater as drinking water. Arsenic was identified as the heavy metal most risky to public health. A total of 39.87% of respondents used groundwater for drinking, but most of the population in Pangalengan (76.47%) and Pacet (80%) used groundwater as their source of drinking water. Both areas are located near geothermal activities, where the arsenic content in the soil is found to be higher. This research has validated that arsenic, predicted to be most risky to public health, has been found in individual biological samples and is associated with DNA damage levels, with findings as follows: 1) arsenic concentrations in biological samples are higher in the exposed group compared to the unexposed group (p < 0.05 in toenails), and higher in the skin cancer cases group compared to controls; 2) arsenic in biological samples is found to exceed normal limits only in blood, not in urine and toenails; 3) DNA damage levels (8-OHdG) in blood plasma are found to be higher in the unexposed group compared to the exposed group and higher in the skin cancer cases group compared to controls (p < 0.05); and 4) multivariate regression analysis found a positive association between arsenic in exposure biomarkers (urine, toenails, and blood) and levels of 8-OHdG in blood plasma after adjusting for BMI and blood glucose (p < 0.05). The risk management recommendations from this research are the maximum arsenic concentration that can be consumed by the community throughout their adjusting for BMI and blood glucose (p < 0.05). The risk management recommendations from this research are the maximum arsenic concentration that can be consumed by the community throughout their lives without causing carcinogenic risks is much lower than the value set in Minister of Health Regulation (Permenkes) No. 492 of 2010, which is 0.0023 mg/L for adult females and 0.0022 mg/L for adult males. Thus, based on this research, the criteria used in Regulation No. 492 of 2010 need to be tightened and revised to ensure public safety against arsenic exposure. Furthermore, this study concludes the importance of taking preventive actions to reduce the risk of arsenic exposure from groundwater for drinking purposes, such as considering restrictions on the use of groundwater as a source of drinking water and providing safe drinking water sources (Piped Water Supply Systems) that do not contain arsenic, especially in areas near geothermal system activities. This study also recommends further research aimed at developing simple household-scale technologies to reduce arsenic concentrations in water, thus minimizing health risks for the consuming population. Additionally, further research to monitor arsenic concentrations in drinking water and monitor cancer cases in the community remains necessary on an ongoing basis. The scientific contribution generated consists of the discovery of one of the contaminants most risky to public health due to its presence in groundwater for drinking purposes, namely arsenic (abbreviated as "As"). This research has also identified the presence of arsenic in biological samples of the population (blood, urine, and toenails) and its association with the concentration of arsenic in consumed groundwater and the level of DNA damage in individual bodies. The study found that arsenic in the study area is suspected to originate from natural sources (release of arsenic from geological formations) and anthropogenic activities.