This study assessed the environmental risks and regional variations associated with using titanium gypsum in road construction. It revealed that the conventional HJ/T299-2007 leaching method underestimates heavy metal leaching rates from titanium gypsum by approximately 1%, potentially leading to an underestimation of environmental risks. Further analysis indicated that Pb, Ni, As, Cd, and Zn leach from titanium gypsum road materials to varying extents, while Mn poses a notable exceedance risk with an 11% probability of surpassing limits and a maximum exceedance factor of 1.8. Significant disparities in regulatory thresholds for titanium gypsum pollutants were observed among 11 provinces along the Yangtze River, with the highest threshold (Qinghai) nearly five times greater than the lowest (Jiangxi). Rainfall was identified as a key contributor to these regional differences. The findings suggest that traditional assessment methods underestimate titanium gypsum risks and highlight the need for enhanced national solid waste evaluation frameworks. Additionally, given the substantial regional risk variations, differentiated management strategies are recommended.

This study examines the assessment and management strategies for odor risks during emergency cleanup of VOC-contaminated waste. By analyzing illegally dumped VOC waste, the impact on odor intensity levels and exceedance probabilities in nearby residential areas was evaluated. Utilizing a VOC source emission model, a Gaussian plume dispersion model, and Monte Carlo simulations under various meteorological conditions, the effectiveness of the control measures was assessed. Key pollutants included ethylbenzene, toluene, styrene, and m/p-xylene, which, despite posing minimal short-term health risks (PHI: 0.17–0.64), exhibited significant odor risks (Odor PHI: 127–1156). At 20 m from the source, the probability of the odor intensity exceeding Level 2.5 approached 100%, decreasing to 85% at 50 m and further declining with distance. Atmospheric stability shifts—from very unstable (Class A) to stable (Class F)—increased the odor intensity from 0.5 to 2.5. Under moderately stable conditions (Class E), m/p-xylene had a 44.2% probability of exceeding an odor intensity level of 2.5. Even at 250 m, the odor intensity levels ranged between 1.2 and 1.7, remaining perceptible. Effective mitigation strategies include establishing appropriate buffer distances and using adsorption materials like activated carbon.