Toxic Metal Aerosols Detection: Enhanced Spark-Induced Breakdown Spectroscopy with Intuitive Software Interface for Community Use

EHSAN GOFTARI, Evan Gittings, Junbeom Jang, Brenda Lopez, Christopher Wallis, Anthony S. Wexler, Hanyang Li, San Diego State University

     Abstract Number: 194
     Working Group: Instrumentation and Methods

Abstract
To advance environmental monitoring of toxic air contaminants, we have developed a novel, cost-efficient Spark-Induced Breakdown Spectroscopy (SIBS) instrument engineered for the detection and quantification of airborne particulate metals (Toxic metal Aerosol Real Time Analyzer, TARTA). We have recently optimized TARTA’s design (TARTA 2.0) to include a combined electrode holder and ground electrode with increased surface area to improve particle collection efficiency. These enhancements have enabled a more compact, user-friendly instrument with an 8” x 10” footprint, weighing only 6 lbs and powered by a 12 VDC battery, suitable for mobile monitoring. The performance of TARTA 2.0 was validated in a series of laboratory experiments using nebulized elemental standard solutions, demonstrating reliable sensitivity and improved limits of detection (LODs) for a wide range of metals, with LODs ranging from as low as 1.03 ng/m³ for Mn to 26.6 ng/m³ for As.

To improve accessibility for community use, we also developed an intuitive software interface that runs on a Raspberry Pi, removing the need for a laptop or technical training, resulting in a substantial reduction of TARTA's operational costs. The software includes simple menu options, real-time metal concentration display, and a new adaptive monitoring mode. The new adaptive mode automatically adjusts the sampling duration based on ambient particulate matter (PM) levels detected by an integrated Plantower sensor inside TARTA, eliminating the need for users to set sampling times manually and enabling efficient operation in environments with unknown or fluctuating air quality. Our findings highlight the potential of TARTA 2.0 as a practical and accessible tool for community-based monitoring of hazardous air pollutants, supporting efforts to reduce toxic metal exposure and protect public health. Ongoing research will expand the range of detectable pollutants, refine quantification methods, and validate the instrument under diverse environmental conditions.