Environmental Science and Pollution Research International

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  • [期刊] Study of organochlorine pesticides and heavy metals in soils of the Juarez valley: an important agricultural region between Mexico and the USA
    摘要:The Juarez Valley is an important agricultural region in northern Mexico, conveniently organized into three modules (I to III). For decades, their soils have been exposed to organochlorine pesticides (OCPs) and also have been irrigated with wastewaters, which may contain heavy metals. Nowadays, there is very limited information regarding the presence of OCPs and heavy metals in these soils. Thus, the aim of this study was to diagnose these soils for OCPs and heavy metal content by using gas chromatography coupled with electron micro-capture detector and atomic absorption spectrometry, respectively. The results indicated that 4,4 '-dichlorodiphenyldichloroethylene and 4,4 '-dichlorodiphenyltrichloroethane were primarily disseminated across the three modules since they were found in 100% and 97% of the analyzed soils, respectively. According to international regulations, none of the determined OCP concentrations are out of the limits. Additionally, the Cu, Zn, Fe, Pb, and Mn were found in all sampled soils from the three modules. The highest concentration of Fe was found in module II (1902.7 +/- 332.2 mg kg(-1)), followed by Mn in module III (392.43 +/- 74.43 mg kg(-1)), Zn in module I (38.36 +/- 26.57 mg kg(-1)), Pb in module II (23.48 +/- 6.48 mg kg(-1)), and Cu in module I (11.04 +/- 3.83 mg kg(-1)) (p <= 0.05). These values did not exceed the limits proposed by international standards. The Cd was detected in most of the analyzed soils and all their values, with an average of 2 mg kg(-1), surpassed the Mexican standards (0.35 mg kg(-1)). This study has mapped the main OCPs and heavy metals in the Juarez Valley and can serve as a starting point to further monitor the behave of xenobiotics. Since these recalcitrant compounds might be bio-accumulated in biological systems, further analytical methods, as well as remediation techniques, should be developed.
  • [期刊] Wood biochars and vermicomposts from digestate modulate the extent of adsorption-desorption of the fungicide metalaxyl-m in a silty soil
    摘要:This study aimed to investigate changes in metalaxyl-M sorption-desorption capacity of soil following the addition of two types of amendments. Two biochars (BC) from grapevine pruning residues (BC-G) and spruce wood (BC-S) and two vermicomposts (VC) obtained vermicomposting digestates from a mixture of manure and olive mill wastewater (VC-M) and buffalo manure (VC-B) were used. Using a batch equilibration method, the materials and a silt loam soil non-amended or amended with each material at 2% (w/w) were interacted with the fungicide at a concentration of 2 mg L-1 for kinetics study and in the range 1-20 mg L-1 for sorption isotherms. Kinetics results showed that metalaxyl-M onto the amendments and non-amended soil followed preferentially a pseudo-second-order model, thus indicating a chemisorption process. Sorption isotherm data of the product on BC and VC fitted well the Freundlich equation, whereas those on non-amended and amended soil followed preferentially a linear model. The K-Fads values were 995.2, 788.5, 55.2, 52.1, 6.4, 6.0, 3.4, 2.6 and 1.5 L kg(-1) for BC-G, BC-S, VC-M, VC-B, soil-BC-G, soil-BC-S, soil-VC-M, soil-VC-B and non-amended soil, respectively. Product desorption from each soil sample occurred to a lesser extent than sorption. Highly significant correlations (P <0.005) were found between the values of sorption and desorption constants of all adsorbents and organic C content, thus confirming the prominent role of organic matter in the sorption process of metalaxyl-M.
  • [期刊] Erratum: Correction to: Hemotoxic effects of some herbicides on juvenile of Nile tilapia Oreochromis niloticus (Environmental science and pollution research international (2019) 26 30 (30857-30865))
    摘要:The correct presentation of Table 2 is shown in this paper.
  • [期刊] Eco-friendly pesticide based on peppermint oil nanoemulsion: preparation, physicochemical properties, and its aphicidal activity against cotton aphid
    摘要:Using organic insecticides including plant oils, it is possible to design a new perspective for the control of insect pests. In this research, nanoemulsion formulations of Mentha piperita, wild-type essential oil (EO) were prepared utilizing high-energy ultrasonication process. Physicochemical properties of nanoemulsions were precisely studied by measurement various parameters including pH, viscosity, conductivity, and zeta potential. Experimental design by the aid of response surface methodology (RSM) was used to highlight the physicochemical roles of EO percentage (1% to 5% (v/v)) and surfactant concentration (3% to 15% (v/v)) for achieving minimum droplet diameter with high physical stability. The nanoemulsion formulations were then characterized using dynamic light scattering, transmission electron microscopy, and optical clarity. Afterward, an appropriate model between the variable factors (EO percentage and surfactant concentration) and the response (hydrodynamic particle size) was statistically developed. Under the optimum conditions, nanoemulsion with hydrodynamic particle size less than 10 nm with high physical stability is obtainable. Bioassay experiments were carried out to elucidate the effects of nanoemulsion on the cotton aphid. Synthesized nanoemulsion formulations showed relatively high contact toxicity (average value of LC50 was about 3879.5 ± 16.2 μl a.i./L) against the pest. On the basis of the obtained results, prepared nanoemulsion using M. piperita is potentially applicable as organic insecticides against cotton aphid. Graphical abstract.
  • [期刊] Stereoselective metabolism and potential adverse effects of chiral fungicide triadimenol on Eremias argus
    摘要:Reptiles are an important part of vertebrates and are the primitive terrestrial vertebrates. However, lots of reptile species are endangered or susceptible to extinction. It is no doubt that contaminants are one of the important reasons for the decline of the lizard population. In this study, the selective metabolism of triadimenol (TN) in the male Eremias argus lizards and the toxic effects of TN on lizards were studied. TN chiral isomers were separated and detected by HPLC-MS/MS system with Lux Cellulose-1 column. Tissue distribution experiments showed the existence of stereoselectivity biotransformation of TN enantiomers among organs in lizards, and RR-TN preferentially emerged over the other enantiomers. The antioxidant enzymes (SOD, CAT, GST) activities and MDA content assays demonstrated that TN induced oxidative stress in most organs, especially in the liver, and the histopathology analysis showed the severe liver and testis damage caused by 14-day continuous TN gavage. The reproductive effects of TN-induced reflected in the increased sex hormone testosterone. This research confirms that TN could induce hepatic and reproductive toxicity of E. argus lizard.
  • [期刊] The effect of a glyphosate-based herbicide on acetylcholinesterase (AChE) activity, oxidative stress, and antioxidant status in freshwater amphipod: Gammarus pulex (Crustacean)
    摘要:This study had determined the effect of glyphosate-based herbicide (GBH) on acetylcholinesterase (AChE) enzyme activity, oxidative stress, and antioxidant status in Gammarus pulex. Firstly, the 96-h LC50 value of glyphosate on G. pulex was determined and calculated as 403 μg/L. Subsequently, the organisms were exposed to sub-lethal concentrations (10, 20, and 40 μg/L) of the determined GHB for 24 and 96 h. The samples were taken from control and GBH-treated groups at 24 and 96 h of study and analysed to determine the malondialdehyde (MDA) and reduced glutathione (GSH) levels, the AChE, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) enzyme activities. In the G. pulex exposed to GBH for 24 and 96 h, the MDA level increased significantly (p <0.05). The GSH level, the AChE, the CAT, and the GPx activities decreased compared with the control group (p <0.05). G. pulex exposure to GBH for 24 h showed a temporary reduction in the SOD. GBH exposure led to oxidative stress in the G. pulex as well as affected the cholinergic system of the organism. These results indicated that the parameters measured may be important indicators of herbicide contamination in G. pulex.
  • [期刊] Solar-driven photocatalytic treatment as sustainable strategy to remove pesticide residues from leaching water.
  • [期刊] Solubility and reactivity of surfactant-enhanced alkaline hydrolysis of organophosphorus pesticide DNAPL
    摘要:The study presented in this paper evaluated the effectiveness of surfactants in enhancing mass removal of organophosphorus pesticides (OPPs) from soil under highly alkaline conditions and potential for enhancing in situ alkaline hydrolysis for treatment of OPPs, particularly parathion (EP3) and methyl parathion (MP3). In control and surfactant experiments, hydrolysis products EP2 acid, MP2 acid, and PNP were formed in non-stoichiometric amounts indicating instability of these compounds. MP3 and malathion were found to have faster hydrolysis rates than EP3 under the conditions studied. All surfactants evaluated increased solubility of OPPs under alkaline conditions with four nonionic alcohol ethoxylate products providing the greater affect over the polyglucosides, sulfonate, and propionate surfactants evaluated. The alcohol ethoxylates were shown to provide substantial mass removal of OPPs from soil. Hydrolysis rates were typically slower in the presence of surfactant, despite the relatively higher aqueous concentrations of OPPs; this was likely due to micellar solubilization of the OPPs which were therefore less accessible for hydrolysis. The results of this study support the use of surfactants for contaminant mass removal from soil, particularly under alkaline conditions, and may have implications for use of some surfactants in combination with other technologies for treatment of OPPs.
  • [期刊] Herbicide biomonitoring in agricultural workers in Valle del Mayo, Sonora Mexico
    摘要:Valle del Mayo is an important agricultural area at the northwest of Mexico where up to 20,000 L of a mix composed of glyphosate and tordon is used in drains and canals. This study was carried out in order to evaluate the cellular damage caused by glyphosate, aminomethylphosphonic acid (AMPA), and picloram in agricultural workers. Biomonitoring was performed through the quantification of herbicides in urine using HPLC (high-performance liquid chromatography) to then evaluate the cellular damage in exposed people by means of an evaluation of micronuclei and cellular proliferation in lymphocyte cultures. The urine samples (n = 30) have shown a concentration of up to 10.25 μg/L of picloram and 2.23 μg/L of AMPA; no positive samples for glyphosate were reported. The calculation of the external dose reveals that agricultural workers ingest up to 146 mg/kg/day; however, this concentration does not surpass the limits that are allowed internationally. As for the results for the micronuclei test, 53% of the workers showed cellular damage, and the nuclear division index test reported that there was a significant difference (P <0.05) between the exposed and the control population, which indicated that the exposure time to pesticides in the people of Valle del Mayo can induce alterations which can cause chronic damage.
  • [期刊] Toxicity of the herbicide flurochloridone to the aquatic plants Ceratophyllum demersum and Lemna minor
    摘要:As a new and efficient selective pre-emergence herbicide, flurochloridone (FLC) has been widely promoted in recent years but readily results in residues in nature. As the primary producers and restorers of the water environment, aquatic plants are at risk of FLC exposure. In the present research, we studied the phytotoxicity of FLC in Lemna minor and Ceratophyllum demersum. The physiological and growth responses of these two aquatic plants exposed to different concentrations of FLC (0, 20, 100, 300, 1000, and 2000 μg/L) were measured. The results showed that FLC (≥ 20 μg/L) could cause serious photosynthesis pigment damage and bleaching in C. demersum and L. minor. Significant oxidative damage was observed in L. minor at 20 μg/L FLC, while there was no severe oxidative damage in C. demersum. At 100-300 μg/L FLC, peroxidase (POD) and superoxide dismutase (SOD) were activated to scavenge free radicals in L. minor, while POD acted as a protective enzyme in C. demersum. At higher concentrations of FLC (≥ 1000-2000 μg/L), L. minor reached less than healthy stability through the regulation of the antioxidant enzyme system and the chlorophyll a/b value. POD, SOD, and protein content returned to normal levels, and the growth parameters increased. However, in C. demersum, the enzymes POD and SOD and soluble protein were damaged, and oxidative stress reached the highest level at 1000-2000 μg/L FLC. Taken together, our results suggested that when treated with FLC, L. minor was more sensitive at lower doses (20 μg/L) and more adaptive at higher doses (1000-2000 μg/L) than C. demersum.