Sorption of Polycyclic Musks on Soil Components of Different Aggregate Sizes: The Effect of Organic Matter-Mineral...

Polycyclic musks (PCMs) in soils have been of increasing concern because of their potential characteristics of persistence, bioaccumulation, and ecological risk. However, little is known about their fate process in soil environment. Here, two PCMs namely galaxolide (HHCB) and tonalide (AHTN) were selected as sorbates to explore their sorption process in soils. Sorption batch experiments with six soils and their different aggregate fractions were carried out to elucidate the effect of organic matter-mineral interactions in different aggregate fractions on sorption of these two PCMs. The possible causes of variation in the organic carbon-normalized partition coefficient (K_oc) for HHCB and AHTN have been investigated. The strong influence of organic matter-mineral interactions on K_oc was evidenced by the large variation in K_oc on HF-treatment for both bulk soils and their different aggregate fractions. This study verified the dual effect of organic matter-mineral interactions among selected soils, and in promoting or inhibiting sorption may be related to the types of organic matter-mineral interactions. There were also interactions between soil components with different aggregate sizes, which affected the variation of K_oc in the bulk soil. This study represents a valuable contribution to the understanding of the fate processes and behaviors of HHCB and AHTN in soils and its implication on the risk assessment.