Standardized Household Dust Sampling Method for Airborne Metal Exposure Assessment - A New Perspective on Chemical Monitoring

Resumo

Introduction: Air pollution is a cross-cutting determinant in public health. Household dust has emerged as an important route of exposure, especially after the COVID-19 pandemic, which increased the amount of time people spend indoors. This environmental compartment can accumulate various toxic substances such as metals, pesticides, PCBs, PBDEs, PAHs, fungi, and microorganisms, all with potential impacts on human health. In this context, dust serves as a relevant indicator of chronic exposure to pollutants. However, the lack of methodological standardization still limits its large-scale application in environmental and epidemiological studies. Objective: Assessment of Atmospheric Metal Contamination in the Rio de Janeiro Metropolitan Region through Household Dust Analysis Using a Standardized Approach and a Novel Sampler. Methods and Materials: Eleven households in the Rio de Janeiro Metropolitan Region were conveniently selected for monitoring over two years. A polystyrene device (30 × 30 cm) was developed for dust collection, positioned 2 meters high in two different rooms for 60 days each season. Dust was collected using an air pump (20 L/min) attached to cassettes with cellulose ester membranes. Metal concentrations were determined by graphite furnace atomic absorption spectrometry. Results and Conclusion: Three rounds of household dust collection were analyzed between June 2023 and July 2024, focusing on the metals Cd, Cr, Ni, and Pb. Contamination was assessed using the Enrichment Factor (EF) and the Geochemical Index (Igeo), based on the São Paulo Geochemical Atlas and using iron as the reference element. Cadmium showed 100% of the samples with extreme contamination in all rounds; chromium ranged from moderate to extreme in 25% to 93% of the samples; nickel ranged from 93% to 100%; and lead ranged from 90% to 100%. The methodology developed in this study proved to be effective, standardized, low-cost, and scalable for monitoring metals in indoor environments. In addition to detecting and quantifying the presence of contaminants, it allowed for the mapping of a relevant chronic exposure scenario, which remains overlooked by public environmental health policies. The findings emphasize the importance of incorporating this approach into public health strategies, particularly for vulnerable populations exposed to diffuse contamination sources.