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Norman JE, Mahler BJ, Nowell LH, Van Metre PC, Sandstrom MW, Corbin MA, Qian Y, Pankow JF, Luo W, Fitzgerald NB, Asher WE, McWhirter KJ. Daily stream samples reveal highly complex pesticide occurrence and potential toxicity to aquatic life. Sci Total Environ 2020; 715:136795. [PMID: 32018098 DOI: 10.1016/j.scitotenv.2020.136795] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 06/10/2023]
Abstract
Transient, acutely toxic concentrations of pesticides in streams can go undetected by fixed-interval sampling programs. Here we compare temporal patterns in occurrence of current-use pesticides in daily composite samples to those in weekly composite and weekly discrete samples of surface water from 14 small stream sites. Samples were collected over 10-14 weeks at 7 stream sites in each of the Midwestern and Southeastern United States. Samples were analyzed for over 200 pesticides and degradates by direct aqueous injection liquid chromatography with tandem mass spectrometry. Nearly 2 and 3 times as many unique pesticides were detected in daily samples as in weekly composite and weekly discrete samples, respectively. Based on exceedances of acute-invertebrate benchmarks (AIB) and(or) a Pesticide Toxicity Index (PTI) >1, potential acute-invertebrate toxicity was predicted at 11 of 14 sites from the results for daily composite samples, but was predicted for only 3 sites from weekly composites and for no sites from weekly discrete samples. Insecticides were responsible for most of the potential invertebrate toxicity, occurred transiently, and frequently were missed by the weekly discrete and composite samples. The number of days with benthic-invertebrate PTI ≥0.1 in daily composite samples was inversely related to Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness at the sites. The results of the study indicate that short-term, potentially toxic peaks in pesticides frequently are missed by weekly discrete sampling, and that such peaks may contribute to degradation of invertebrate community condition in small streams. Weekly composite samples underestimated maximum concentrations and potential acute-invertebrate toxicity, but to a lesser degree than weekly discrete samples, and provided a reasonable approximation of the 90th percentile total concentrations of herbicides, insecticides, and fungicides, suggesting that weekly composite sampling may be a compromise between assessment needs and cost.
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Affiliation(s)
- Julia E Norman
- U.S. Geological Survey, Sacramento, CA, United States of America
| | | | - Lisa H Nowell
- U.S. Geological Survey, Sacramento, CA, United States of America.
| | | | | | - Mark A Corbin
- U.S. Environmental Protection Agency, Washington, DC, United States of America
| | - Yaorong Qian
- U.S. Environmental Protection Agency, Fort Meade, MD, United States of America
| | - James F Pankow
- Portland State University, Portland, OR, United States of America
| | - Wentai Luo
- Portland State University, Portland, OR, United States of America
| | | | - William E Asher
- University of Washington, Seattle, WA, United States of America
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Abstract
The authors report 5 cases of acquired obsessive-compulsive disorder occurring later in life. Patients' presentations, which could be readily mistaken for a delusional disorder, were associated with depressive symptoms and basal ganglia lesions, implicating dysfunction of the cortical-basal ganglia-thalamic-cortical neuroanatomical circuit.
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Affiliation(s)
- R C Chacko
- Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, USA
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