Chemical characterization of air and soil contaminants associated with menstrual hygiene products

In India, a majority of menstruating women prefer using sanitary pads, which are typically disposed through burning or as sanitary waste, eventually reaching the soil. This study aimed to analyze the chemical composition of sanitary pads and menstrual cups and assess their environmental impact post-disposal. Fourier-Transform Infrared (FTIR) analysis was employed to identify the materials constituting the sanitary products. Unused pads were found to be composed of polyethylene, silica gel, and several unidentified aromatic chemicals. In contrast, menstrual cups consisted solely of silicone, which is a commonly used biocompatible material suitable for making biomaterials used as inserts inside the human body. Experiments were conducted to determine the impact of pads on air and soil quality. Simulated menstrual fluid (SMF), mimicking blood and vaginal fluid, was utilized in all in vitro experiments. In contaminated soil samples comprising used sanitary pads, there was a significant reduction in macronutrients such as nitrogen and phosphates, and micronutrients including iron, chlorides, copper, manganese, boron, molybdenum, nickel, and zinc. There was an average decrease of 85.48% organic matter and 84.24% moisture across all pad-contaminated soils. No significant variation in pH was observed among the soil samples. The total plate count in soil exposed for 182 days showed a reduction of more than 99% in microflora compared to the control. In contrast, soil exposed to used cups and SMF exhibited no significant reduction in macronutrients, micronutrients, pH, moisture content, or organic matter. Combusted gas analysis revealed that burning menstrual pads at room temperature and ambient air conditions emitted particulate matter and harmful gases, including methane, HCl, HF, SO₂, CO, CO₂, aromatic volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). The chemical analysis of soil and combustion gases indicated that the disposal of single-use sanitary pads posed environmental hazards, suggesting the potential benefits of using reusable menstrual cups. This study brings forth valuable evidence about the adverse effects of disposable sanitary pads on the environment, thus highlighting the need for alternative menstrual products such as reusable cups to mitigate ecological harm.