In 2026, ASTA collaborated with academic and industry partners in Vietnam to conduct a follow-up study expanding upon 2025 research investigating the potential role of lichen and moss present on the outermost bark layer of Vietnamese cassia in relation to heavy metal contamination. By comparing lead concentrations in bark, underlying wood, and surface-growing lichen, the study confirmed that lichen function as bioaccumulators, effectively capturing airborne dust and heavy metal particulates from the surrounding environment. These findings indicate that lead contamination is primarily a surface issue, suggesting that the issue is manageable through targeted mitigation strategies, including lichen removal prior to cassia processing. As next steps, researchers will evaluate technical approaches for lichen removal, assess seasonal variability in lead accumulation, identify potential sources of airborne lead, and support the development of enhanced pre-processing standards and best practices.

At the 2026 Annual Meeting, Lien Hoang Thi of the Vietnam Pepper & Spice Association (VPSA) presented an update on ongoing research in Vietnam examining sources of lead in cassia. The research has progressed from evaluating soil lead levels to assessing lead concentrations within and on cassia bark, with findings indicating that contamination is primarily a surface issue. These results suggest lead can be effectively managed through targeted mitigation strategies, such as lichen removal prior to processing. Next steps include evaluating lichen removal methods, assessing seasonal variation in lead accumulation, identifying potential airborne sources of lead, and informing enhanced pre-processing standards and best practices.