ABSTRACT
Tailwater recovery system (TWR) sediment quality in Mississippi, USA, was evaluated seasonally within the storage reservoir and drainage ditch system from 2016 to 2019 for pesticide contamination, effects and bioavailability to Hyalella azteca (Saussure). Sediment bioassays (28-day) measured H. azteca survival and growth and tissue residue risks from sediment pesticide exposure. Sediment pesticide contamination comprised six current-use herbicides, three current-use insecticides, three legacy insecticides and one metabolite (p,p’-DDE). Sediment clomazone, bifenthrin and ΣDDT concentrations were greatest in drainage ditch sites during summer and fall. H. azteca tissue pesticide residues comprised three current-use herbicides and insecticides, as well as two legacy insecticides. Tissue residue clomazone, Ζ-cypermethrin and ΣDDT concentrations were greatest in drainage ditch sites during fall and winter. H. azteca survival and growth varied seasonally and spatially with lowest survival during fall and winter and lowest survival in the storage reservoir relative to drainage ditch sites during winter. Growth decreased during winter and spring with lowest growth in drainage ditches relative to the storage reservoir during spring. Patterns of associated survival and growth with tissue pesticide residues indicate increased risk during fall in TWR and where system water flows mobilise sediment pesticides increasing the risk of ecological impairment.
Acknowledgements
We wish to thank John Massey, Calvin Vick (retired), Wade Steinriede, Mark Griffith and Lisa Brooks for assistance with sample collection, processing and chemical analysis. Disclaimer: The use of trade, firm, or corporation names is solely for the information and convenience of the reader. Mention of names does not constitute an official endorsement or approval by the USDA or the Agricultural Research Service of any product or service to the exclusion of others that may be suitable. The USDA prohibits any discrimination in all its programmes and activities on the basis of race, colour, national origin, age, disability, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because any part of an individual’s income is derived from any public assistance programme.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
The data that support the findings of this study are available from the corresponding author, REL, upon reasonable request.
Additional information
Notes on contributors
R. E. Lizotte
Richard E. Lizotte is a research ecologist.
M. T. Moore
Matthew T. Moore is a supervisory ecologist.
R. Russell
Renee Russell is a chemist at the Water Quality and Ecology Research Unit, National Sedimentation Laboratory, USDA-ARS, Oxford, Mississippi USA.
M. A. Locke
Martin A. Locke is a supervisory soil scientist and director at the National Sedimentation Laboratory, USDA-ARS, Oxford, Mississippi USA.