IoT-enabled FMIND pipeline with chemical validation for microplastic contamination risk assessment in bottled water...

Microplastic contamination in bottled drinking water is an emerging environmental and public health concern, particularly when bottles are exposed to varying storage and thermal conditions. This study introduces FMIND (fuzzy microplastic inference for detection risk), an IoT-enabled fuzzy inference framework for rapid and low-cost microplastic contamination risk assessment. Bottled water stored in PET and stainless-steel containers under sunlight, shade, and freezer conditions was evaluated using IoT sensors measuring temperature, turbidity, and total dissolved solids (TDS) before and after 30 days of storage. Statistical analysis revealed strong correlations between sensor variations and contamination-related physicochemical indicators, including turbidity (r = 0.861), TDS (r = 0.793), and temperature (r = 0.565) (p < 0.001). The FMIND fuzzy model applied 12 Sugeno rules to generate a contamination risk score (0-100), while the HFIRM-GT enhanced configuration improved classification consistency within the experimental dataset, achieving an F1 score of 0.91. Laboratory validation using FTIR spectroscopy, SEM imaging, and EDAX elemental analysis on selected high-risk samples supported the presence of polymer-associated microplastic fragments in sunlight-exposed PET bottles. The proposed framework does not directly quantify microplastics through IoT sensors; instead, it estimates contamination risk using indirect physicochemical indicators supported by laboratory validation. FMIND integrates IoT sensing, fuzzy reasoning, and chemical validation into a unified and interpretable framework for periodic bottled water contamination risk assessment. The reported predictive performance reflects evaluation within a limited experimental dataset and should be interpreted as preliminary proof-of-concept validation rather than generalized field-scale performance. The system provides a scalable and cost-effective approach that supports Sustainable Development Goal 3 (Good Health and Well-Being), Sustainable Development Goal 6 (Clean Water and Sanitation), and Sustainable Development Goal 12 (Responsible Consumption and Production).