Investigating the Relationship between Environmental Physical Factors and the Toxicity Index of Waste Components from Solar Panels

The rapid expansion in the adoption of renewable energy sources, particularly through the use of photovoltaic panels, highlights the pressing issue of recycling these modules making it increasingly relevant today. Currently, approximately 90% of solar panels reach the end of their lifecycle through burial. The polymer components found in crystalline solar panels, such as ethylene vinyl acetate copolymer and polyvinyl fluoride, pose substantial environmental risks when disposed of in landfills. In this study, we investigated the toxicity associated with the polymer components of polycrystalline solar panels at the end of their operational lifespan. Our goal was to illuminate the correlation between the toxicity of these materials and various environmental factors. We primarily utilized biotesting techniques, drawing upon the chemotactic responses of the protozoan Paramecium caudatum, which allows for the detection of even trace amounts of substances that may be missed by other analytical approaches. The impact of poorly soluble compounds, such as the polymer materials found in solar panels, has not yet been investigated using this test organism. Following our experiments, we conducted a statistical analysis to evaluate how the toxicity levels found in polymer waste correlate with factors such as exposure duration, temperature, and sample fraction size. Our analysis highlighted significant factors influencing the fluctuation of toxicity indices in the components of end-of-life solar panels, leading to the creation of models that illustrate changes in toxicity with varying temperature and extraction time. Statistical analysis (ANOVA, p < 0.05) confirmed that exposure time is the most significant factor increasing the toxicity index (T) of polymers. The obtained logarithmic models (R2 > 0.94) predict an increase in the toxicity of leaching of panel components in landfills, which indicates the environmental risks of their disposal and the need to develop disposal regulations.