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Abstract Salinity has been reported to impact the octanol–water partition coefficient of organic contaminants entering aquatic ecosystems. However, limited data are available on the impacts of salinity on their partitioning from the aqueous phase to adjacent organic compartments. The pesticides bifenthrin, chlorpyrifos, dicloran, myclobutanil, penconazole, and triadimefon were used to investigate the effects of salinity on their partitioning to capelin (Mallotus villosus) eggs in 5 practical salinity units (PSU) versus 25 PSU artificial seawater (ASW). The partitioning coefficient was significantly higher in 25 versus 5 PSU ASW for bifenthrin, chlorpyrifos, dicloran, penconazole, and triadimefon by 31%, 28%, 35%, 28%, and 20%, respectively, while for myclobutanil there was no significant difference. Moreover, pesticide partitioning to store‐bought capelin eggs was consistent with the partitioning observed for the standard assay species, inland silversides (Menidia beryllina) eggs, after partitioning between the eggs and exposure solution had reached a state of equilibrium. The present study illustrates the importance of considering the influence of salinity on the environmental partitioning and fate of hydrophobic organic contaminants in aquatic ecosystems.Environ Toxicol Chem2024;43:299–306. © 2023 SETAC.
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Tolerance to salinity and thermal stress by larvae and adults of the serpulid annelid Ficopomatus enigmaticus
Abstract The serpulid annelidFicopomatus enigmaticusis a widely distributed invader of shallow‐water, brackish habitats in subtropical and temperate regions, where it has numerous damaging ecological and economic effects. Its distributional pattern suggests that temperature and salinity play important roles in limiting its distribution, but because other factors often covary with these, drawing strong conclusions from these patterns is difficult. In an effort to more clearly identify the effects of these factors, we examined tolerance to acute thermal (16–28°C) and salinity (0–35 psu) stress by larvae (5‐day exposure, unfed) and adults (14‐day exposure, unfed) ofF. enigmaticusin the laboratory experiments. Larvae showed higher mortality at the highest temperature tested 28°C; adult survival was unaffected by temperature. Neither larvae nor adults survived exposure to pure freshwater (0 psu), but survived well at salinities ranging 3.5–35 psu. In addition, high salinity did not slow tube growth in adults. These results suggest that salinity stress, in particular, does not directly limit the distribution ofF. enigmaticusto low‐salinity habitats. Experimental work on the distribution ofF. enigmaticusis uncommon in the literature, but is likely needed to identify the abiotic or biotic factors that limit the distribution of this frequently invasive species.
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- Award ID(s):
- 1756531
- PAR ID:
- 10460316
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Invertebrate Biology
- Volume:
- 138
- Issue:
- 4
- ISSN:
- 1077-8306
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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