Abstract

This study aimed to assess the generation rate and composition of household hazardous waste (HHW) in Nakhon Si Thammarat Municipality, Thailand. A questionnaire survey was conducted to collect data on HHW generation and disposal practices from households in the municipality. Soil samples were collected and analyzed for heavy metals (cadmium, chromium, mercury, nickel, and lead) and PCBs contamination. The potential health risks from ingestion exposure associated with heavy metals and polychlorinated biphenyls (PCBs) contamination in the soil were evaluated. The result revealed that in 2023, the HHW generation rate was 11.95 kg/household/year, with the highest percentages occurring of electronic waste (17.40%), fluorescent lamps (16.98%), spray cans (12.38%), cleaning products (11.30%), and engine oil and lubricant oil products (9.87%). The majority of residents (92.90%) disposed of hazardous waste and general waste together in public waste containers. However, the health risk assessment indicated that the levels of heavy metals and PCBs in the soil were within the safe acceptable range for residents, with a total lifetime cancer risk from ingestion exposure of less than 1E-06 for both adults and children. The findings highlight the need for improved waste separation practices and the implementation of effective hazardous waste management strategies to minimize potential health risks and environmental impacts. This study serves as a basis for developing targeted interventions and policies to enhance household hazardous waste management in the municipalities and similar urban areas in Thailand.