Sulfur dioxide (SO2 ) is a sharp and non-flammable gas from coal combustion activities, fuel oil power plants, copper smelting, and volcanic eruptions. The accumulation of SO2 exposure cans detriment to lung function, respiratory tract, irritation, asthma, and even causes death. This study aimed to calculate the value of RfC from SO2 exposure in communities in residential settlements around the area of Palembang�s fertilizer industry, Indonesia by using NOAEL SO2 in white rats and the weight and height of Indonesian exposed to SO2. This was an observational cross-sectional study. To analyze the data, manual quantitative analysis was made. The samples were adults and adolescents, seventeen years old or above, who had settled for more than 2 years. The variable of this research were the concentration of SO2 in the settlements around the fertilizer industry, residents� body weight, height, respiratory rate, exposure time per day, and body surface area, weight and body surface of white rats, No Observed Adverse Effect Level (NOAEL), Animal Km, Human Km and Reference of Concentracion (RfC). The results showed that the average SO2 concentration was 0.248 mg/m3 (0.0946 ppm). This meant that it is below the threshold limit value according to PP RI No. 41 of 1999 namely 900 µg/Nm3 (0.34 ppm). However, it is approaching the highest limit permitted by Permenaker No. 5 of 2018 which stated the limit to be equal to 0.25 mg/m3 (0.095 ppm). The average SO2 RfC obtained in this study was 0.04 mg/kg. It is less than the one issued by EPA/NAAQS 2010, that is equal to 0.21 mg/kg and it means that the RfC result of this study is safer for humans than of the others. Nevertheless, the presence of SO2 around residential areas, which is almost close to TLV and can increase at any time, can bring a negative effect to public health. Therefore, continuous controlling is highly needed. It includes reducing SO2 concentration, controlling SO2 emissions and evaluating industrial activities periodically in order to maintain air quality and level of exposure so health effects can be well-controlled. © Indian Journal of Public Health Research and Development. All rights reserved.

People who have lived more than 22 years in settlements around the fertilizer industry X are at risk of being exposed to SO2 from the increase in exhaust emissions produced by the boilers and power generation equipment in the fertilizer industry. The purpose of this study was to determine the Risk Quotient (RQ) due to exposure to SO2 and to measure the duration of exposure to SO2 that is safe in the residential area around the fertilizer industry X. This research is a quantitative study with an environmental health risk analysis method, with a sample size of 297 adult population respondents in residential areas around the center of SO2 emissions in the fertilizer industry X area. Data analysis was done using manual data calculations to determine the intake of SO2 (non carcinogenic), risk level or risk quotient (RQ), and safe duration (Dt safe) exposure to SO2 in the population around the fertilizer industry X. The results showed that the average non-carcinogenic intake of SO2 in settlements around the fertilizer industry X was at 0.057427415mg/kg/day. While the average risk quotient is 1.788347507 (RQ> 1), from a total of 297 respondents as many as 197 respondents with RQ> 1 and 100 respondents with RQ 50 of the population in settlements around the fertilizer industry X have health risks resulting from exposure to SO2. The average safe duration of exposure to SO2 in the population in settlements around the fertilizer industry X is 23.47 years, depending on the food intake and body condition of the respondents. The recommendation that can be given is to increase the weight of respondents and the right diet pattern by consuming nutritional intake that can detoxify the main toxin to reduce sulfur dioxide levels in the body, one example is the provision of vitamins E and C which can reduce oxidative effects such as lipid peroxidation and membrane damage in erythrocytes due to exposure to sulfur dioxide2. Besides that, a related stakeholder policy is needed to periodically measure SO2 concentrations in community residential areas around the fertilizer industry X, so that the air quality of people exposed to SO2 can be monitored and is still within safe limits. The company holds a CSR program involving the surrounding community by conducting routine health checks, greening programs around the fertilizer industrial area6. © 2019, Indian Journal of Public Health Research and Development. All rights reserved.