Development and In-vitro evaluation of a passive inline activated charcoal laparoscopic smoke filter

Laparoscopic surgery procedures generate surgical smoke containing hazardous particulate matter, volatile organic compounds (VOCs), aldehydes, and bioaerosols, posing potential occupational health risks to operating room personnel. Existing commercial smoke evacuation systems are often expensive, bulky, and dependent on powered suction systems, limiting their adoption in resource-constrained healthcare settings. This study aimed to evaluate the performance of a low-cost inline laparoscopic smoke filtration system under controlled In-vitro conditions. An In-vitro bench-top simulation model was used to generate electrocautery-induced surgical smoke, with air samples collected upstream and downstream of the filtration unit during independent experimental trials (n=5). The inline filtration device consisted of a multi-layer activated charcoal-based filtration system integrated with standard laparoscopic tubing. Particulate matter (PM_₂.₅ and PM_₁₀) was quantified using a calibrated laser particle counter, while gaseous contaminants including formaldehyde, benzene, and acrolein were analyzed using VOC/formaldehyde detection systems. The filtration system demonstrated particulate reduction efficiency ranging from 78–85% and gaseous contaminant reduction ranging from 70–80% under simulated operative conditions. Formaldehyde concentration decreased from 0.82 ± 0.05 ppm pre-filtration to 0.21 ± 0.03 ppm post-filtration, corresponding to 74.4% reduction. Benzene and acrolein concentrations were reduced by 77.8% and 75.0%, respectively. Stable airflow was maintained within 6–10 L/min, with minimal impact on pneumoperitoneum stability (<1 mmHg variation). The system also improved laparoscopic visual clarity and reduced smoke accumulation during continuous electrosurgical activation. Although filtration efficiency was lower than premium HEPA/ULPA-based commercial systems, the compact, non-powered, and economical design demonstrated dual-phase reduction of particulate and gaseous contaminants in a practical inline configuration. This preliminary study suggests that an inline activated charcoal-based smoke filtration system may offer an economically accessible design with potential utility for reducing surgical smoke exposure, particularly in resource-limited settings. Further in-vivo and clinical validation studies are required to establish long-term safety and clinical effectiveness.