Biochars were produced from pig manure to elucidate the influence of biochars with high ash contents on the fate of pesticides. Adsorption and catalytic hydrolysis of carbaryl and atrazine on original biochars and deashed biochars were investigated. The two pesticides were substantially adsorbed by the biochars, with organic carbon normalized sorption coefficient (K(oc)) values of 10(2.65)-10(3.66) L/kg for carbaryl and 10(1.90)-10(3.57) L/kg for atrazine at C(e) of 0.5 mg/L. Hydrophobic effect alone could not explain the sorption, and several other processes including pore-filling and π-π electron donor-acceptor interactions were involved in pesticide adsorption. Adsorption increased greatly on the deashed biochar, indicating that some organic sorption sites in the original biochars were blocked or difficult to access due to their interactions with inorganic moiety. The pesticides were found to hydrolyze faster in the presence of biochars, and in the presence of biochar pyrolyzed at 700 °C, carbaryl and atrazine were decomposed by 71.8% and 27.9% in 12 h, respectively. The elevated solution pH was the main reason for the enhanced hydrolysis; however both the mineral surface and dissolved metal ions released from the biochars were confirmed to catalyze the hydrolysis.
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http://dx.doi.org/10.1016/j.jhazmat.2012.11.046 | DOI Listing |
Environ Int
November 2024
Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA.
Objective: Elevated pesticide concentrations have been found in dust from homes with residents who use agricultural pesticides, but few studies have compared these concentrations to quantitative measures of their use. We evaluated household pesticide dust concentrations in relation to quantitative, active ingredient-specific metrics of agricultural pesticide use in the Biomarkers of Exposure and Effect in Agriculture Study.
Methods: Participants provided vacuum dust samples (2013-2018) and information regarding recent (last 12 months) and lifetime pesticide use.
Sci Total Environ
November 2024
Institute for Sustainable Agricultural, Food, and Environmental Science, The Pennsylvania State Univ., University Park, PA 16802, USA; Department of Agricultural and Biological Engineering, Penn State University, University Park, PA, USA.
Environ Toxicol Chem
December 2023
Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Quebec, Canada.
The rainbow trout gill cell line (RTgill-W1), via test guideline 249 of the Organisation for Economic Co-operation and Development, has been established as a promising New Approach Methodology, although to advance confidence in the method more case studies are needed that: 1) expand our understanding of applicability domains (chemicals with diverse properties); 2) increase methodological throughput (96-well format); and 3) demonstrate biological relevance (in vitro to in vivo comparisons; gill vs. other cells). Accordingly, the objective of our study was to characterize the cytotoxicity of 19 pesticides against RTgill-W1 cells, and also liver (RTL-W1) and gut epithelial (RTgutGC) cell lines, and then to compare the in vitro and in vivo data.
View Article and Find Full Text PDFSci Total Environ
June 2023
Department of Environmental Science, University of Arizona, Tucson, AZ, USA; Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, USA. Electronic address:
Due to global water scarcity and population growth, multiple solutions are needed to conserve and collect water, especially in arid and semi-arid regions of the planet. As the practice of harvesting rainwater grows, it is important to assess the quality of roof-harvested rainwater (RHRW). This study measured twelve organic micropollutants (OMPs) in RHRW samples collected between 2017 and 2020 by community scientists, with approximately two hundred RHRW samples and corresponding field blank analyzed annually.
View Article and Find Full Text PDFBioprocess Biosyst Eng
September 2022
Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Mexico, México.
Groundwater and surface water bodies may have contaminants from urban, industrial, or agricultural wastewater, including emerging contaminants (ECs) or micropollutants (MPs). Frequently, they are not efficiently removed by microbial action due to their minimal concentration in water and the low microbiota affinity for complex compounds. This work developed a process allowing the adsorption of contaminants and their simultaneous biodegradation using horizontal tubular fixed-bed biofilm reactors (HTR).
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