Stereoselective Bioaccumulation and Metabolite Formation of Triadimefon in Tubifex tubifex

Abstract

Triadimefon, a chiral fungicide, could be metabolized to triadimenol which has two chiral centers. In this work, Tubifex tubifex was exposed to triadimefon through the aqueous and soil phase to explore the relative importance of the routes of uptake. Bioaccumulation of triadimefon in tubifex was detected in both treatments, and the kinetics of the accumulation processes were significantly different in these two experiments. In spiked water treatment, (S)-triadimefon was preferentially accumulated over the (R)-triadimefon, whereas the enantioselective bioaccumulation was not detected in the spiked soil microenvironment. Simultaneously, four stereoisomers of triadimenol were also found in the tubifex tissue. Although the amount of these stereoisomers were different from each other with relatively more accumulation of the most fungi-toxic stereoisomer (1S,2R), the abundance ratios in the two exposure treatments were similar at the same sampling, following the order (1S,2S) > (1R,2S) > (1R,2R) > (1S,2R). The bioaccumulation factor was calculated for parent compound triadimefon and metabolite enrichment factor for metabolite. The results showed that both uptake routes, epidermal contact in the aqueous phase and ingestion of solid particles in soil, were important to the bioaccumulation of the triadimefon and triadimenol in tubifex.

Stereoselective bioaccumulation, transformation, and toxicity of triadimefon in Scenedesmus obliquus

“…It is common that the stereoisomers of chiral pesticides generate antagonism in toxic effects. It is difficult to speculate the order of toxicity potency of chiral pesticide stereoisomers, because the toxicity of these stereoisomers to an organism may be subject to many biological activities, such as transportation, transformation, assimilation, accumulation, and metabolism . However, the EC 50 values of triadimenol stereoisomers in this study were found to be relatively invariant, regardless of the exposure time, indicating that the toxicities were stable during the incubation.…”

Enantioselective behaviour of tetraconazole during strawberry wine‐making process

“…[6][7][8][9] Besides, there is not any maximum residue limit for the tetraconazole in strawberry in China. [12][13][14][15][16] For instance, the bioactivity of (−)-Rtebuconazole is higher than that of (+)-S-tebuconazole, 17 which exhibited high toxicity to aquatic non-target organisms (Scenedesmus obliquus, Daphnia magna, and Danio rerio). The oral toxicity study demonstrated that tetraconazole was slightly toxic to mammals and moderately toxic to birds.…”

Assessment of tissue-specific accumulation, elimination and toxic effects of dichlorodiphenyltrichloroethanes (DDTs) in carp through aquatic food web

“…Tubifex tubifex (Oligochaeta, Tubificidae) was chosen as prey, which could accumulate DDTs from sediment and transfer them to carp ( Cyprinus carpio ). T. tubifex is one of the most widespread and ubiquitous groups, which was considered to be a good bio-indicator 53, 54 . Carp are omnivorous demersal fish in fresh water ecosystems, which can serve as bio-indicators of environmental contaminants and play significant roles in assessing potential risk 44 .…”