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1.
Chemosphere ; 263: 128061, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33297067

ABSTRACT

The present study aimed to assess the ecological risk of 30 current-use agricultural pesticides and biocides in the soil, sediments and aquatic organisms of a mixed land-use basin located in the Depressed Pampas Region of Argentina. Risk Quotients (RQs) were used to evaluate the chronic risk in soil and aquatic organisms, while Toxic Units (TUs) were used to assess the acute risk in sediment-dwelling organisms and aquatic biota. Acetochlor, hydroxy-atrazine, glyphosate, AMPA, metolachlor, imidacloprid and tebuconazole were the only pesticide residues detected (>30%) and quantified in all the matrices evaluated. Glyphosate and AMPA showed the highest concentrations, being their mean and maximum levels 27.90-176.00 µg kg-1 and 270-712.50 µg kg-1 in soils, 8.28-32.0 µg kg-1 and 6.85-17.50 µg kg-1 in sediments, and 1.88-4.36 µg L-1 and 0.66-1.03 µg L-1 in surface water. The RQs in soils showed high chronic risk, mainly due to AMPA and imidacloprid. The TUs in sediments showed acute risk in dwelling organisms, mainly due to glyphosate and imidacloprid. RQs assessment showed a range of chronic risk levels according to the site/sampling event, with higher contribution of atrazine and its metabolites, and acetochlor, whereas TUs assessment showed no acute risk in aquatic biota. In contrast to Europe, in Argentina, there are no restrictions regarding the use of atrazine, acetochlor, imidacloprid and glyphosate to protect aquatic life. Thus, it is recommended that the current Argentine pesticide regulations should be modified to prevent ecological risk and protect ecosystems.


Subject(s)
Disinfectants , Herbicides , Pesticides , Water Pollutants, Chemical , Argentina , Ecosystem , Environmental Monitoring , Europe , Herbicides/analysis , Pesticides/analysis , Risk Assessment , Soil , Water , Water Pollutants, Chemical/analysis
2.
Environ Toxicol Chem ; 36(12): 3206-3216, 2017 12.
Article in English | MEDLINE | ID: mdl-28631831

ABSTRACT

In the present study, we evaluated the spatial and temporal trends of current-use pesticides in surface water and sediments as well as their relationship with hydrological stream dynamics within the agricultural watershed of El Crespo stream (Buenos Aires Province, Argentina). We sampled 2 contrasting sites: site 1 (upstream), surrounded by agricultural lands, and site 2 (downstream), surrounded by natural grasslands. Most of the applied pesticides (glyphosate, 2,4-D, atrazine, tebuconazole, and imidacloprid) were detected at high frequencies in surface water samples at both sites. However, only glyphosate and aminomethylphosphonic acid (AMPA) were present at high concentrations and had a significant spatial-temporal trend. The highest concentrations were found during spring 2014 at site 1, in association with the intense rains that occurred in that season. The fact that glyphosate and AMPA concentrations were higher than the rest of the studied compounds is closely related to the land use within the watershed, as glyphosate was the most applied herbicide during the fallow period of glyphosate-resistant crops (soybean, maize). The pesticide mixture had a significant spatial-temporal trend, reaching the highest levels during storm flow events in spring 2014. The intensive rains in spring 2014 could be the main factor influencing stream hydrology and pesticide behavior at El Crespo watershed. The estimated annual pesticide losses were 3.11 g/ha at site 1 and 0.72 g/ha at site 2. This result indicates that an attenuation process could be decreasing pesticide loads during downstream transport from site 1 to site 2. Environ Toxicol Chem 2017;36:3206-3216. © 2017 SETAC.


Subject(s)
Glycine/analogs & derivatives , Pesticides/analysis , Water Pollutants, Chemical/analysis , Argentina , Atrazine/analysis , Crops, Agricultural , Environmental Monitoring , Geologic Sediments/chemistry , Glycine/analysis , Herbicides/analysis , Isoxazoles , Neonicotinoids/analysis , Nitro Compounds/analysis , Organophosphonates/analysis , Rain , Rivers , Tetrazoles , Triazoles/analysis , Water Movements , Glyphosate
3.
Environ Toxicol ; 29(9): 1063-71, 2014 Sep.
Article in English | MEDLINE | ID: mdl-23315857

ABSTRACT

Previous studies in the wetland macrophyte Bidens laevis L have demonstrated that the insecticide endosulfan induces a high frequency of somatic chromosome aberrations in anaphase-telophase (CAAT) but no DNA changes as determined by the single cell gel electrophoresis (Comet) assay. Thus, cytogenetic biomarkers appear to be more sensitive to the toxic effects of the insecticide than the DNA molecule in the studied species. For this reason, the goals of this study were to use cytogenetic biomarkers--CAAT and abnormal metaphase--and defense biomarkers such as the activity of the antioxidant enzymes--guaiacol peroxidases (POD), glutathione reductase, and microsomal and cytosolic (m- and c-) glutathione-S-transferase (GST)--to evaluate in B. laevis effects caused by a commercial formulation of endosulfan. The frequency of CAAT was increased at 5, 10, 50, and 100 µg/L endosulfan with respect to the negative controls by 3.1, 2.5, 2.5, and 3.2-fold, respectively while the frequency of abnormal metaphases was also increased at the same concentrations by 3.5, 2.8, 3.2, and 11.3-fold, respectively. In addition to these aneugenic effects, other abnormalities such as C-mitosis and chromosome clumping were observed at 10 µg/L endosulfan. On the other hand, POD induction at 0.02, 0.5, 5, and 10 µg/L and m-GST inhibition at 0.5, 10, and 50 µg/L in plants exposed during 24 h to endosulfan were observed but all of these responses were highly variable. In conclusion, only cytogenetic biomarkers like CAAT in B. laevis can serve potentially as early warning systems to detect environmentally relevant concentrations of endosulfan in aquatic ecosystems.


Subject(s)
Bidens/drug effects , Endosulfan/toxicity , Insecticides/toxicity , Anaphase , Bidens/enzymology , Bidens/genetics , Biomarkers/metabolism , Chromosome Aberrations , Comet Assay , Genetic Markers , Glutathione Reductase/metabolism , Glutathione Transferase/metabolism , Telophase
4.
Environ Toxicol Chem ; 32(11): 2478-81, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23929711

ABSTRACT

Endosulfan is genotoxic in somatic cells of Bidens laevis, and reproduction could be affected if translocated from roots to flower buds. Hydroponic experiments were conducted to quantify this transfer. While the root uptake of [(14) C] endosulfan and its transfer to aboveground tissues was relatively low, the resulting average flower bud concentration (1.01 ± 0.76 ng/g) after 30 d of exposure to an aqueous concentration of 5 µg/L could still represent a genotoxic risk for germ cells.


Subject(s)
Bidens/chemistry , Endosulfan/analysis , Insecticides/analysis , Plant Roots/chemistry , Plant Shoots/chemistry , Flowers/chemistry , Wetlands
5.
Environ Pollut ; 153(3): 695-8, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18029070

ABSTRACT

The frequency of micronuclei (MN) and chromosome aberrations in anaphase-telophase (CAAT) was determined in root tips of the wetland macrophyte Bidens laevis exposed to environmentally relevant concentrations of endosulfan (0.01, 0.02, 0.5 and 5microg/L) for 48h. MN frequency varied from 0 in negative controls and plants exposed to 0.01microg/L endosulfan to 0-3 in plants exposed to 5microg/L. Moreover, a significant concentration-dependent increase of CAAT was observed. The higher proportion of laggards and vagrand chromosomes observed at 5microg/L would indicate that endosulfan interacts with the spindle interrupting normal chromosome migration. Endosulfan resulted genotoxic to B. laevis, a species of potential value for bioassays and in situ monitoring of environmental contamination by pesticides.


Subject(s)
Bidens/drug effects , DNA Damage , Endosulfan/toxicity , Environmental Pollutants/toxicity , Genes, Plant/drug effects , Insecticides/toxicity , Argentina , Bidens/genetics , Environmental Monitoring/methods , Micronucleus Tests , Mutagenicity Tests/methods , Wetlands
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