Tissue-Specific Accumulation of Orally Administered Short- and Medium-Chain Chlorinated Paraffins in Honeybees (Apis mellifera L.).

ABSTRACT

The prevalence and distribution of chlorinated paraffins (CPs) have been extensively studied in various matrices and organisms; however, there is a lack of information about insects, particularly in honeybees. To address this gap, we studied young honeybee workers exposed to short- and medium-chain CPs (SCCPs and MCCPs) at an environmentally relevant concentration of 10 mg/L for 7 days, followed by a 7-day elimination period. Results indicated that CPs could transfer into the head after oral consumption and SCCPs and MCCPs exhibited clear bioaccumulation trends midgut > hindgut > head. An evaluation of congener group distribution patterns demonstrated that the dominant congener groups in all target tissues were C11-13Cl7-8 and C14Cl7-8 for SCCPs and MCCPs, respectively, consistent with the treated CP standards. In honeybees, a significant negative relationship was observed for the log concentration of MCCP congener groups and their log KOW, but not with their log KOA. Conversely, no such correlation was found for SCCPs. These findings suggest that honeybees have a high potential to bioaccumulate MCCPs, particularly those with a low log KOW, and exhibit weak selectivity for SCCPs.