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Organophosphorus pesticides (OPs) are used in crops to eradicate pests, but are of concern to the public, attributable to their potential toxicity to human health. In the present study, a biodegradable composite film containing citrate-stabilized gold nanoparticles (AuNPs) was developed to detect pesticides. The proposed composite film has distinctive structural and functional characteristics as a colorimetric recognition indicator for detecting OPs (malathion, fenthion, dimethoate, and chlorpyrifos). The developed film was morphologically and spectroscopically characterized through electron microscopy and UV–Vis spectrometry, respectively. The spherical-shaped and monodispersed AuNPs were obtained with an average particle size of 20 nm. The aggregation of the AuNPs composite film in the presence of pesticides led to a change in color from red to blueish purple, which could be visually observed on the surface of the vegetables. Under optimum conditions, the detection limit was 2.02 μM, 1.33 μM, 2.27 μM, and 11.77 μM for malathion, fenthion, dimethoate, and chlorpyrifos, respectively. The developed films demonstrated good biodegradability, and excellent storage stability, sensitivity and selectivity, with recovery values ranging from 99.60 to 103.68%, and relative standard deviation (RSD) values from 0.56 to 5.76%. The findings indicate a sensitive and selective sensing biodegradable colorimetric film, which is eco-friendly, biodegradable, considered to have promising low-costs, and a renewable source material for detecting pesticide residues.

The main objective of this study was to assess the pesticide removal efficiency of chitosan in grape juice during clarification. The grape juice was spiked with six selected pesticides (chlorpyrifos, ethion, diazinon, fenitrothion, fenthion and phorate) and clarified with chitosan at different concentrations and at three different incubation times (1, 2 and 4 h). The effect of chitosan on the level of pesticides in grape juice during clarification was quantified using modified QuEChERS method with gas chromatography with tandem mass spectrometry (GC-MS/MS). The method for pesticide quantification has been validated. The maximum removal was obtained for chlorpyrifos (98%) and ethion (97%) at 0.5% of chitosan concentration for 1 h incubation followed by phorate (96%), fenthion (95%), fenitrothion (94%) and diazinon (86%) at 1% of chitosan concentration for 2 h incubation time. The juice was clarified with other clarifying agents such as activated carbon, gelatin, casein and bentonite and its pesticide removal efficiency was compared with chitosan. The pesticide removal level could be correlated with the properties of selected pesticides and clarifying agents. The results indicated that the chitosan can act as an effective pesticide scavenger and it leads to the potential application of chitosan in fruit juice clarification.

The production of Nile tilapia (Oreochromis niloticus) in Brazil exhibits the highest growth rate in the world and represents approximately 45% of the total fish production. The objective of the present study was to assess the risk for human health due the consumption of tilapia farmed in net cages in eight aquaculture parks in Brazil. The concentrations of pesticides (40 compounds), metals (Mn, Ni, Zn, Cd, Pb, and Sn), arsenic, and cyanotoxins (microcystins) were evaluated in 16 fish from each park. Among analyzed pesticides, pyraclostrobin (0.18–0.32 mg/kg) and fenthion (0.0026–0.0037 mg/kg) exhibited values above the limit of quantification in the tilapia from Aracoiaba, Castanhao, and Ilha Solteira. The highest concentrations of As (0.44 μg/g) in fish tissues were found in Juara, Mn (0.21 μg/g) in Castanhao, and Zi (11.5 μg/g) were found in Tres Marias. Furnas and Linhares exhibited the lowest metal concentrations. The estimated daily intake of muscle by the average Brazilian with 70 kg body weight is below the reference dose for all studied metals in all parks. Total free microcystins showed an accumulation pattern (muscle < gill < liver). The highest concentration in muscle was found in Castanhao (1043 μg/kg) samples. The results showed that fish exhibited metal, As, and pesticide tolerable daily intake (TDI) below the limit and pose low risk for human consumption. Otherwise, TDI for microcystins in fish of all studied parks was above the maximum level recommended by the World Health Organization, indicating that there exists a toxicity risk of fish consumption.

Plasmonic nanoparticles offer attractive benefits for the detection of environmental contaminants due to their high extinction coefficients and unique optical properties. Excess use of OP pesticides has been found to have adverse effects on human health and the environment. Here, we demonstrate the use of plasmonic silver (Ag), gold (Au) and bimetallic silver-gold (Ag-Au) nanoparticles (NPs) to detect and distinguish between organophosphorus (OP) pesticides. The NPs were found to detect the thion pesticides: ethion, parathion, malathion, and fenthion) in real time. In each case, the interaction of the pesticides with the plasmonic NPs were found to result in wavelength shifts of the localized surface plasmon resonance (LSPR) accompanied by color changes. The wavelength shifts were characteristic of the pesticide structure and concentration. The interaction between the sensors and the pesticide was a result of the soft metal surface binding to the soft sulfur atom of the pesticide. Similarly, oxon pesticides showed no effect on the LSPR of the NPs. The three plasmonic NPs showed limits of detections (LOD) in ppm range for all pesticides under real-time analysis. The LOD of Ag NPs with ethion, fenthion, malathion, and parathion were 9 ppm, 11 ppm, 18 ppm, and 44 ppm, respectively. The LOD of Au NPs with ethion, fenthion, malathion, parathion were 58 ppm, 53 ppm, 139 ppm, and 3203 ppm, respectively. Ag-Au NPs with ethion, fenthion, malathion, and parathion showed LOD values of 228 ppm, 231 ppm, 1189 ppm, and 1835 ppm, respectively. The ability of the plasmonic NPs to detect the selected pesticides in natural environments was tested under simulated natural conditions in the presence of dissolved organic matter (DOM). Steep gradients in the sedimentation plots revealed that the time dependent interaction of each OP pesticide with the NP surface was accompanied by a considerable change in the LSPR indicative of colloidal destabilization over time. All pesticides showed nearly the same trend in their sedimentation with the plasmonic NPs. The stability of the nanoparticles in the colloidal medium was described by classical DLVO theory, which showed that the net interaction was attractive.

Following the loss of two key pesticides, dimethoate and fenthion, producers and regulators need to develop new fruit fly management options. A systems approach is a likely measure in the post dimethoate and fenthion era. The risk of fruit fly can be mitigated at the regional, district and farm level. Some measures such as awareness and exclusion are common across all three levels. Pest control measures will be based on an understanding of climate, biology and pesticides. In this present paper, 28 different risk mitigation options that can be used in a systems approach in Australia are discussed.

This study was conducted to monitor the susceptibility status of Aedes aegypti (Linnaeus) larvae in the Sunda Islands of Indonesia against various organophosphates and organochlorines. Larval bioassay was performed in accordance with the World Health Organization standard protocol. Field-collected and reference strains of Ae. aegypti larvae were tested against diagnostic doses of eight larvicides belonging to organophosphates and organochlorines, namely bromophos (0.050 mg/liter), chlopyrifos (0.002 mg/liter), fenitrothion (0.020 mg/liter), fenthion (0.025 mg/liter), malathion (0.125 mg/liter), temephos (0.012 mg/liter), DDT (0.012 mg/liter), and dieldrin (0.025 mg/liter). Mortality rates of larvae were recorded at 24-h posttreatment. This study showed that Ae. aegypti larvae from Padang, Samarinda, Manggarai Barat, and South Central Timor were susceptible to both fenitrothion and dieldrin (mortality rates ≥ 98%). About 6 out of 10 field strains of Ae. aegypti larvae were resistant (

Summary Background Pesticide poisoning is among the most common means of suicide globally, but can be prevented with regulation of the most hazardous agents. We aimed to compare the lethality of pesticides ingested by our cohort, seek evidence on variation between human and regulatory animal toxicity, and establish change over time in the case fatality of individual pesticides in Sri Lanka. Methods We examined the case fatality of agricultural pesticides in a prospective cohort in nine hospitals serving rural populations in Sri Lanka. We included all patients (>11 years) who had presented to a South Asian Clinical Toxicology Research Collaboration study hospital during the study period. Patients were enrolled by clinical research assistants and were regularly reviewed. Identification of the ingested pesticide was generally on the basis of history or positive identification of the container, supported by nested blood analysis. Findings From March 31, 2002, to Dec 31, 2019, 34 902 patients (median age 29 years [IQR 21–40]; 23 060 [66·1%] male) presented with a possible or known pesticide self-poisoning. We identified 23 139 specific pesticides that were ingested. Poisoning was fatal in 2299 (6·6%) patients. Case fatality varied greatly from 0·0% (several substances) to 41·8% (paraquat). The three most toxic agents (ie, paraquat, dimethoate, and fenthion) were banned between 2008 and 2011. Since 2013, the five agents causing the most deaths (ie, profenofos, propanil, fenobucarb, carbosulfan, and quinalphos) had a case fatality of 7·2–8·6%. A steady decline was seen in overall case fatality of pesticide poisoning (10·5% for 2002–06 to 3·7% for 2013–19), largely attributable to pesticide bans. A modest fall in case fatality for non-banned pesticides was also seen. Interpretation Declines seen in case fatalities of poisonings with non-banned pesticides suggest that medical management improved over time. The human data for acute toxicity of pesticides should drive hazard classifications and regulation. We believe that a global benchmark for registration of pesticides should include a less than 5% case fatality after self-poisoning, which could prevent many deaths and have a substantial effect on global suicide rates. Funding The Wellcome Trust and the National Health and Medical Research Council of Australia. Translations For the Sinhala and Tamil translations of the abstract see Supplementary Materials section.

The aim of this study was to investigate reported cases of honeybee mortality incidents and the potential association to pesticide exposure and to their metabolites. The same honeybee samples were also assessed for Varroa mites, and Nosema microsporidia provoked infections to provide an integrated picture of all observable stressors that may impact bees' survival. Thus, honeybee samples from different areas of Greece (2014–2018) were analyzed for the presence of pesticide residues and metabolites. In this context, an existing LC-ESI-QqQ-MS multiresidue method of analytes of different chemical classes such as neonicotinoids, organophosphates, triazoles, carbamates, was enriched with additional active substances, developed and validated. A complementary GC-EI-QqQ-MS method was also exploited for the same scope covering pyrethroid compounds. Both methods monitored more than 150 active substances and metabolites and presented acceptable linearity over the ranges assayed. The calculated recoveries ranged from 65 to 120% for the three concentration levels, while the precision (RSD%) values ranged between 4 and 15%. Therefore, this approach proved sufficient to act as a monitoring tool for the determination of pesticide residues in cases of suspected honeybee poisoning incidents. From the analysis of 320 samples, the presence of 70 active substances and metabolites was confirmed with concentrations varying from 1.4 ng/g to 166 μg/g. Predominant detections were the acaricide coumaphos, several neonicotinoids exemplified by clothianidin, organophosporous compounds dimethoate and chlorpyrifos, and some pyrethroids. Metabolites of imidacloprid, chlorpyrifos, coumaphos, acetamiprid, fenthion and amitraz were also identified. Concerning Nosema and Varroa they were identified in 27 and 22% of samples examined, respectively, verifying their prevalence and coexistence with pesticides and their metabolites in honeybees.

Fenthion an active compound contained in EC 500 lebaycid pesticides that are toxic. To reduce the level of toxicity will be degradation in sonolysis, ozonolysis and sonozolysis with the addition of TiO2-anatase. Degradation results in sonolysis, ozonolysis and sonozolysis measured by UV-Vis spectrophotometer at wavelength of 400-600 nm. From the research that has been made degradation result fenthion 6 mg/L in sonolysis without addition of catalyst of 37.5% and with the addition of TiO2-anatase catalyst obtained for 65.12% of degradation for 60 minutes. In ozonolysis at the same time obtained percent degradation of 39.77% without the addition of catalyst and 81% with the addition of TiO2-anatase catalyst. Percent degradation fenthion compound without the addition of TiO2-anatase catalyst after a 60-minute sonozolysis obtained at 91.7%.

The objective of this study was to evaluate the capability of the bacteria Bacillus safensis strain FO-36bT isolated from pesticide-polluted soil in degrading fenthion and temphos in mineral salt media (MSM). Fenthion and temphos were incubated with the isolated bacteria. Samples were drawn at 0, 3, 7, 14, and 30 days to analyze residual fenthion and temphos content with gas chromatography (GC) and high-performance liquid chromatography (HPLC), respectively. The loss of the initial pesticide concentration (400 mg/L) over time was determined and used to compute the half-lives using a biphasic model. Gas chromatography-mass spectrometry (GC-MS) was used to identify the major metabolites as well as to re-confirm the identity of starting material (fenthion). The results showed that the bacterium was still viable at the end of each incubation period. The biodegradation of fenthion and temphos followed a biphasic model. The half-lives of fenthion in the first and in the second phase were 0.29 and 3.69 days, respectively, whereas the corresponding values for temphos were 0.11 and 1.15 days. Only one metabolite "iso-fenthion" (O, S-dimethyl O-[3-methyl-4-(methylthio)phenyl] phosphorothioate) was detected in fenthion culture, while no metabolites were detected in temphos culture. Based on the half-lives, this bacterium was able to degrade temphos at a faster rate than fenthion. Key words: Biodegradation, fenthion, temphos, bacteria, pesticides-contaminated soil, Sudan.

A simple method for determining 33 pesticides with a wide polarity range (logKow 0.6-4.5) in aquatic products was developed based on LC-MS/MS. The target analytes included three types of widely used pesticides: insecticides, fungicides and herbicides. Based on the optimization of ultrasonic assisted extraction and GPC clean-up procedures, the matrix effect, extraction recoveries and LOD were improved distinctively. LOQ of this method was below 0.5ng/g for all pesticides, which is superior to values in the literature, and the matrix effect was reduced effectively (-14.7% to 7.5%). The method was successfully applied to investigate the pesticide residue levels of twenty-five samples including seven common kinds of fishes from Northeast China. The results showed that all targeted pesticides were present in the fish samples; however, their levels were low, except for atrazine, linuron, ethoprophos, tetrachlorvinphos, acetochlor and fenthion. Atrazine and linuron caught our attention because the concentrations of atrazine in fish samples from Liaoning province were in the range of 0.5-8ng/g (w/w) with mean concentration of 2.3ng/g, which were far above those of other pesticides. The levels of linuron were in the range of 0.6-6ng/g (mean concentration 2.8ng/g), which were the highest among all targeted pesticides in the Inner Mongolia. This is the first systematic investigation on the characteristics and levels of these pesticides in aquatic products from northeast China. Considering their toxicity and bioaccumulation, the potential risk of atrazine and linuron from consuming aquatic products should be paid more attention.

The susceptibility values for field-collected (BG-BG) and laboratory (KS-BG) strains of German cockroaches (BS-BG), Blattella germanica (L.) to five synthetic pyrethroid and three organophosphate insecticides were assessed by topical application. Both KS-BG and BS-BG strains demonstrated the highest levels of susceptibility to deltamethrin with LD50 values of 0.0035 μg/female and 1.5744 μg/female, respectively. The KS-BG strain demonstrated the lowest susceptibility level to fenthion with an LD50 value of 0.0698 μg/female, while the BS-BG field population showed the lowest susceptibility to bifenthrin with 4.6811 μg/female. The BS-BG field population showed resistance levels of 50 to 640 fold higher against the eight pesticides evaluated compared to the KS-BG strain. The resistance ratios (RR) of the eight pesticides were compared using populations of B. germanica that were collected from the same locality during 2007 and 2014. The field population of B. germanica collected during 2014 demonstrated significantly high resistance to an organophosphates and all pyrethroids when compared with those collected during 2007, but RR values were

Adsorption and biodegradation processes for four organophosphate pesticides (chlorpyrifos, diazinon, fenthion, dichlorvos) in wetlands and agricultural drains in Meric-Ergene Basin, Turkey have been investigated. Koc (organic carbon normalized partition coefficient) values for all pesticides except diazinon were higher in more aromatic Pamuklu Drain sediments, indicating the possible influence of aromaticity on the extent of adsorption. The average half-lives of pesticides in Gala Lake sediments and Pamuklu agricultural drain sediments ranged from 2.25 to 69.31 days with chlorpyrifos exhibiting the slowest biotransformation rate and dichlorvos having the fastest biotransformation rate. The presence of humic substances and hydroperiod of wetlands have been identified as possible factors that affected the behavior of organophosphate pesticides in this study. The results from this study provide insight into the constructed wetland design offered for the mitigation of organophosphate pesticides in the basin.

Herein, contaminants remaining in distillate and distillers&rsquo, stillage were quantitatively measured after distillation. After rice bran powder was contaminated with 10 ppm of lead (Pb) and cadmium (Cd) or 0.02&ndash, 1.27 ppm of five pesticides (terbufos, fenthion, iprobenfos, flutolanil, and ethoprophos) followed by fermentation, single-stage distillation was performed. In the obtained distillate, no Pb or Cd was found, as expected. However, when the pesticides were added as contaminants, trace&ndash, 0.05 ppm of some pesticides were detected in the distillate, possibly due to the high vapor pressure (e.g., that of ethoprophos) and contamination amount (e.g., that of flutolanil, terbufos, and fenthion). In contrast, none of the contaminating pesticides were observed in the distilled spirits when a fermented liquefaction contaminated with 0.04&ndash, 4 ppm of six pesticides (fenthion, terbufos, ethoprophos, iprobenfos, oxadiazon, and flutolanil) was distilled using a pilot-plant scale distillation column, indicating that the pesticides hardly migrate to the distilled spirits.

RATIONALE Dermal exposure to pesticides may cause severe intoxication and even result in a fatal outcome. To expedite rescue in the emergency department, it is mandatory to develop a point-of-care analytical method for immediate identification of pesticides on the skin of exposed personnel, and to perform immediate dermal decontamination to prevent further harm and optimize the chance for full clinical recovery. METHODS Four of the most commonly used highly toxic pesticides that contaminate the skin were rapidly characterized by thermal desorption electrospray ionization mass spectrometry. The technique was also applied to confirm the completeness of pesticide decontamination from the skin. Pesticide sampling, desorption, ionization, and detection altogether took less than 30 s. In addition, different fabrics of protective garments worn by farmers were assessed with this efficient ambient mass spectrometric technique for their protective capabilities against dermal exposure to pesticides, and scanning electron microscopy was used to observe their different microstructures. The decontaminating efficacies of different cleansing agents for these skin contaminants were also evaluated by this technical platform. RESULTS The repeatability of this method had a low relative standard deviation (

The present study aims at evaluating potential genotoxic and cytotoxic effects caused by the occupational exposure of farmers to pesticide mixtures in the Aitoloakarnania Prefecture (Greece). The aforementioned assessment was conducted through in vivo Cytokinesis Block Micronucleus assay (CBMN assay) in peripheral blood lymphocytes, in relation to chemical analysis of pesticide residues in blood samples. The exposure of the farmers' population studied to different combinations of pesticides induced significant differences in the frequencies of micronuclei (MN) compared to those of the control group. Furthermore, our results indicated a possible clastogenic and aneugenic effect of pesticides on the genetic material of the farmers exposed. Five pesticides (trifluralin, chlorpyriphos methyl, metolachlor, fenthion and dimethoate) and three metabolites (fenthion sulfone, fenthion sulfoxide and 4,4′ DDE) were detected in the 62.5% of blood samples, with mean concentrations ranging from 0.4 ng/ml to 48 ng/ml. Since the farmers studied probably exhibit detectable levels of systematic exposure to the pesticides applied, continuous educational programs focused on the rational and safe use of pesticides, together with implementation of risk communication strategies among farmers are highly recommended.

Organophosphorus (OP) pesticides are widely used to control pests because of their high activity. This study described a rapid and sensitive lateral flow immunochromatographic (LFIC) assay based on up-converting nanoparticles (UCNPs) for multi-residue detection of three OP pesticides. The developed assay integrated novel fluorescent material UCNPs labeled with a broad-specific monoclonal antibody. Based on the competitive platform by immobilized antigen in the test zone, the optimized UCNPs-LFIC assay enabled sensitive detection for parathion, parathion-methyl, and fenitrothion with IC50 of 3.44, 3.98, and 12.49 ng/mL (R 2 ≥ 0.9776) within 40 min. The detectable ability ranged from 0.98 to 250 ng/mL. There was no cross-reactivity with fenthion, phoxim, isocarbophos, chlorpyrifos, or triazophos, even at a high concentration of 500 ng/mL. Matrix interference from various agricultural products was also studied in food sample detection. In the spiked test, recoveries of the three OP pesticides ranged from 67 to 120% and relative standard deviations were below 19.54%. These results indicated that the proposed strip assay can be an alternative screening tool for rapid detection of the three OP pesticides in food samples.

The red-billed quelea (Quelea quelea) is the most important avian pest of small grain crops in semi-arid zones of Africa. Fenthion, an organophosphate, is the main avicide used for controlling the pest but it is highly toxic to non-target organisms. The only readily available pesticide that could replace fenthion is cyanophos, but this chemical is also highly toxic to non-target organisms, although less so than fenthion, and may be more expensive; however, more research on its environmental impacts is needed. Apart from chemical avicides, the only rapid technique to reduce the numbers of quelea substantially is the use of explosives combined with fuel to create fire-bombs but these also have negative effects on the environment, can be dangerous and have associated security issues. The technique is labour intensive and in practice can only be deployed against small (

In this study, the phase I metabolism of fenthion was monitored in three common vegetables in different chamber situations via an in vivo solid-phase microextraction method. The phase I metabolic pathways of fenthion were evaluated based on the in vivo monitoring results and their comparisons among the chamber situations. Enzyme catalysis was found to play a basic and dominant role, whereas light catalysis could promote subsequent transformations that were difficult for enzyme catalysis. Moreover, according to the concentrations of the metabolites and their toxicity, the total concentrations and total toxicity weighted concentrations were calculated to reveal actual residual levels. The relative total and weighted exposure potency values were calculated to account for the fact that only the parent pesticide was considered in the diet exposure risk assessment. In result, both total and weighted approaches indicated a much higher exposure risk. Present study uncovered the potential pesticide exposure risk associated with phase I metabolism and highlighted the toxicity weighted approach, both of which more realistically reflect the exposure risk than the parent compound concentration does. In general, this study may facilitate further illustrating the phase I metabolism of ubiquitous agricultural pesticides, and provide a more realistically understanding of their exposure risk.

An in vivo uptake and elimination tracing study based on solid phase microextraction (SPME) was conducted to investigate the accumulation, persistence and distribution of organochloride pesticides (OCPs) and organophosphorus pesticides (OPPs) in malabar spinach (Basella alba L.) plants. Uptake and elimination of the pesticides were traced in leaves, stems and roots of living malabar spinach plants. Root concentration factor (RCF), distribution concentration factor (DCF) and transpiration stream concentration factor (TSCF) were calculated based on the in vivo tracing data. The tracing data showed that the OCPs were much more accumulative and persistent than the OPPs in roots, while they were similarly accumulative and persistent in leaves and stems. RCF values of the OPPs or OCPs were likely to increase with the increase in LogKow values except fenthion. Obtained DCF values indicated that OPPs and OCPs were more accumulative in the organs containing more lipids. TSCF values showed that the translocation of OPPs and OCPs from roots to foliage was firstly dependent on the hydrophobicity of the compounds, but also significantly affected by the water solubility. This is the first study of generating RCF, DCF and TSCF data in living plants by in vivo sampling method, which provides a foundation to promote the application of in vivo SPME and improve understanding of contaminant behaviors in living plants.

In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography-mass spectrometry (GC-MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC-MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production.

In Japan, Hirschmanniella diversa is an important pest in lotus cultivation in paddy fields and only lime nitrogen is registered for its control. Therefore, additional nematicides are required to control the nematode. The objective of this study was to screen for an effective nematicide. Fourth-stage juveniles and adults of H. diversa sampled from a lotus field were tested in in vitro solution experiments against 37 pesticides that are registered for the pest control of crops in Japan. Carbamate-based benfuracarb, organophosphate-based fenthion, nereistoxin-based cartap hydrochloride and cyanamide showed nematicidal effects against H. diversa. Benfuracarb at 1 &mu, g/mL showed a nematostatic effect on H. diversa in an agar plate assay. Further, H. diversa treated with benfuracarb did not resume activity 7 days post nematicide treatment when transferred to distilled water. Benfuracarb was tested in micro-field experiments, in which H. diversa density and lotus tuber damage levels were monitored. Results showed that benfuracarb reduced H. diversa densities in the roots during the cultivation period in 2012 and consistently reduced damage levels during a five year study period. Thus, benfuracarb is recommended as an effective nematicide to be used for H. diversa control in lotus cultivation.

Indiscriminate use of two broad spectrum pesticides, profenofos and fenthion, in agricultural system, often results in their accumulation in a non-target niche and leaching into water bodies. The present study, therefore, aims at developing a simple and rapid HPLC method that allows simultaneous extraction and detection of these two pesticides, especially in run-off water. Extraction of the two pesticides from spiked water samples using dichloromethane resulted in recovery ranging between 80 and 90%. An HPLC run of 20 min under optimized chromatographic parameters (mobile phase: methanol (75%) and water (25%); flow rate of 0.8 ml min-1; diode array detector at wavelength 210 nm) resulted in a significant difference in retention times of two pesticides (4.593 min) which allows a window of opportunity to study any possible intermediates/transformants of the parent compounds while evaluating run-off waters from agricultural fields. The HPLC method developed allowed simultaneous detection of profenofos and fenthion with a single injection into the HPLC system with 0.0328 mg l-1 (32.83 ng ml-1) being the limit of detection (LOD) and 0.0995 mg l-1 (99.5 ng ml-1) as the limit of quantification (LOQ) for fenthion; for profenofos, LOD and LOQ were 0.104 mg l-1 (104.50 ng ml-1) and 0.316 mg l-1 (316.65 ng ml-1), respectively. The findings were further validated using the soil microcosm experiment that allowed simultaneous detection and quantification of profenofos and fenthion. The findings indicate towards the practical significance of the methodology developed as the soil microcosm experiment closely mimics the agricultural run-off water under natural environmental conditions.

In the last several decades, exposure to pesticides has become a concern to environmental and human health. Many pesticides are environmentally persistent and are characterized by varying degrees of toxicity and adverse effects, including DNA damage. The present study was undertaken to evaluate the genotoxic potential of organophosphate pesticide fenthion in Wistar rats, as assessed by the comet assay. Adult male Wistar rats were treated with a solution of fenthion at a concentration of 40 mg/kg/day, administered intraperitoneally for 18 consecutive days. Rats were killed 24 hours after the last pesticide administration, and the comet assay was performed in peripheral blood cells. The comet assay results revealed that the damage index (19.29 ± 3.59 vs. 7.80 ± 2.25) and the damage frequency (17.00 ± 3.46 vs. 7.5 ± 2.46) found in fenthion-treated rats were significantly higher than those found in the control group (p = 0.001 and p = 0.0006, respectively). The results show that fenthion affects the DNA integrity of rat cells and may induce DNA damage in exposed organisms.

This study was performed to determine the storage stability of organophosphorus pesticide residues in high oil content commodity matrices, peanut and soya bean. The storage conditions included different types of solvents (ethyl acetate, acetone and hexane) and corresponding extracted matrix solutions, light and temperature. It was found that three pesticides degraded quickly especially in ethyl acetate solvent. They decreased greater than 30% when stored for 3 days at −20°C in ethyl acetate; the results showed that the stability could be improved in the extracted matrix solutions. Light had a slight effect for stability of phorate and fenthion, while it played an important effect for disulfoton with the exception of ethyl acetate as solvent. Even at −20°C, exposure to solvents or extracted matrix solution resulted in 40.67, 96.33 and 35.07% loss of phorate, disulfoton and fenthion. Hence, it could be assumed that these three residues could be more stable at lower temperature, in the dark and in acetone or hexane extracted peanut and soya bean solutions.

Fenthion is an organophosphate pesticide commonly used in agriculture and public health for the control of insect pests. The present study investigated the toxic effect of fenthion and the histopathological alterations in the gill tissue of African catfish Clarias gariepinus. The 96 h LC 50 value of fenthion in C. gariepinus determined by probit analysis was found to be 39.97 mg/L. Fish exposed to different fenthion concentrations showed clinical signs such as erratic swimming, attempt to jump out of water, increased opercula frequencies, air gasping, mucus secretion followed by exhaustion and death. To evaluate the histopathological changes in the gill tissue, fish were exposed to 2.0, 4.0 and 8.0 mg/L corresponding to 1/20, 1/10 and 1/5 th , respectively of 96 h LC 50 of fenthion for 21 days and 7 days recovery. Gill disorder and fusion of the secondary lamellar were pronounced in all treatments. Alterations in gill structure exposed to the highest concentration were oedema, lifting of lamellar epithelia, destruction of gill architecture and lamellar fusion. From the findings, it can be deduced that fenthion-induced alterations are irreversible and therefore should be applied with caution in the environment so as to reduce its damage to aquatic organisms. Keywords: Clarias gariepinus , fenthion, lethal concentration, histopathology.

The efficiency of water rinsing for removing fenthion from non-combustible used pesticide containers was investigated. Four hundred empty containers from four olive oil producing areas in Greece were studied. Following triple rinsing cleaning procedures, the amount of fenthion retained in the container ranged from 0.01% to 0.1% w/w of its initial concentration. Extraction was accomplished with acetone, and the extracts were analyzed with a capillary gas chromatographic system coupled with flame ionization detector. The results obtained showed that triple rinsing is an effective procedure for removing fenthion from used pesticide containers, since the remaining pesticide concentration was below the legislated threshold value. Consequently, the containers can be handled as non-hazardous solid wastes.

For simultaneously monitoring two classes of organophosphorus pesticide residues in food samples, a polyclonal antibody against a dual-generic hapten immunogen, which was prepared by conjugating two generic haptens (O,O-dimethyl thiophosphate hapten and O,O-diethyl phosphate hapten) to the same carrier protein BSA, was raised and used to develop a broad-specificity competitive indirect enzyme-linked immunosorbent assay. With the optimized conditions, the developed immunoassay was able to detect 11 organothiophosphate pesticide and 5 organophosphate pesticide residues with detection limits of 0.018–0.135 μg/mL and 0.013–0.171 μg/mL, respectively. Recoveries of paraoxon-ethyl, fenamiphos, parathion-methyl, and fenthion from spiked samples ranged between 85.8 and 105.5 %. The results indicated that the immunoassay developed in this study is suitable for high-throughput screening of these low-molecular-weight contaminants in food samples.

Traditional pesticide residue detection methods are usually complicated, time consuming, and expensive. Rapid, portable, online, and real-time detection kits are the developing direction of pesticide testing. In this paper, we used a surface-enhanced Raman spectroscopy (SERS) technique to detect the organophosphate pesticide residue of phorate and fenthion in apple skin, for the purpose of finding a fast, simple, and convenient detection method for pesticide detection. The results showed that the characteristic wavenumbers of the two organophosphorus pesticides are more easily identified using SERS. We selected the Raman peaks at 728 cm−1 of phorate and 1215 cm−1 of fenthion as the target peaks for quantitative analysis, and utilized internal standards to establish linear regression models for phorate and fenthion. The detection limit was 0.05 mg/L for phorate and 0.4 mg/L for fenthion. This method can be used as a quantitative analytical reference for the detection of phorate and fenthion.

For several decades, control of fruit fly pests in Australia has depended to a large degree on dimethoate, a broad-spectrum organophosphate insecticide that has been widely used on many different crops as well as on ornamental plants. However, many dimethoate use patterns were withdrawn in 2011 following a review by regulatory authorities. This manuscript places dimethoate in context as the latest in a long line of pre-harvest pesticides such as the arsenics, tartar emetic, sodium fluosilicate, nicotine sulphate, the organochlorines, and organophosphates, that have been lost from the fruit fly control toolkit over the past century. The succession of postharvest treatments such as fumigants, dips and sprays is also examined. Dimethoate and fenthion have offered relatively easy and cost effective pest control solutions since the 1960s, but in the absence of equivalent alternatives it is now necessary to develop “systems approaches” based on multiple control strategies and risk assessment. Such approaches represent a fundamental shift in pest management strategy, and will require improved understanding of fruit fly biology to prevent infestation in the field, combined with postharvest surveillance and non-chemical treatments. Some options are briefly discussed.

Based on the common structure of organophosphorus pesticides, O,O-dimethylphosphorothioate, two haptens were synthesised with different spacer arms. The class-specific polyclonal antisera were prepared from the conjugates of haptens and keyhole limpet hemocyanin. Under optimum conditions, a homologous direct competitive enzyme-linked immunosorbent assay (ELISA) method was developed for multi-residue detection of 23 organophosphate pesticides. The most sensitive IC50 values of the multi-residue analysis were estimated as 0.25, 0.65 and 0.80 mg L−1 for methyl parathion (PM), fenitrothion and fenthion, respectively. Furthermore, when the developed ELISA was applied to detection of PM in water samples, adequate spike recoveries in the range from 70.3 to 131% were obtained. It provided a useful multi-residue determination method of organophophorus pesticides.

The organophosphorous (OP) pesticide fenthion is widely used in commercial fruit industry and orchards in South America. Among the metabolic effects in mammals caused by fenthion, hyperglycemia occurs via the activation of hepatic metabolic pathways, which may interfere with the function of several organs and systems. The purpose of this study was to evaluate the effects of acute and sub-chronic levels of fenthion on energy metabolism and liver morphology of frugivorous bats (Artibeus lituratus), which usually feed on fruits cultivated on South American plantations where fenthion is used. Animals were fed fruit treated with fenthion by immersion of fruit in a solution containing fenthion (500 ppm) and an adhesive spreader (200 ppm). Blood glucose levels did not change due to fenthion treatment, but muscle glycogen content increased and carcass fatty acids decreased after acute exposure. An increase in hepatocyte cell diameter further characterized as an increase in vacuolization was observed. The results ...

Background. Pesticide self-poisoning causes one third of global suicides. Sri Lanka halved its suicide rate by banning WHO Class I organophosphorus (OP) insecticides and then endosulfan. However, poisoning with Class II toxicity OPs, particularly dimethoate and fenthion, remains a problem. We aimed to determine the effect and feasibility of a ban of the two insecticides in one Sri Lankan district. Methods. Sale was banned in June 2003 in most of Polonnaruwa District, but not Anuradhapura District. Admissions with pesticide poisoning to the district general hospitals was prospectively recorded from 2002. Results. Hospital admissions for dimethoate and fenthion poisoning fell by 43% after the ban in Polonnaruwa, while increasing by 23% in Anuradhapura. The pesticide case fatality fell from 14.4% to 9.0% in Polonnaruwa (odds ratio [OR] 0.59, 95% confi dence interval [CI] 0.41 – 0.84) and 11.3% to 10.6% in Anuradhapura (OR 0.93, 95%CI 0.70 – 1.25; p 0.051). This reduction was not sustained, with case fatality in Polonnaruwa rising to 12.1% in 2006 – 2007. Further data analysis indicated that the fall in case fatality had actually been due to a coincidental reduction in case fatality for pesticide poisoning overall, in particular for paraquat poisoning. Conclusions. We found that the insecticides could be effectively banned from agricultural practice, as shown by the fall in hospital admissions, with few negative consequences. However, the ban had only a minor effect on pesticide poisoning deaths because it was too narrow. A study assessing the agricultural and health effects of a more comprehensive ban of highly toxic pesticides is necessary to determine the balance between increased costs of agriculture and reduced health care costs and fewer deaths.

The study includes findings about limitations of acetylcholinesterase (AChE) based assay. Eleven organophosphorus pesticides: chlorpyrifos ethyl, chlorpyrifos methyl, DFP, dichlorvos, dimethoate, fenthion, paraoxon ethyl, paraoxon methyl, phosalone, pirimiphos methyl and pirimiphos ethyl were photometrically assayed using AChE as a recognition element. The study was carried out in order to find approachability of AChE based assay. In the first round, common organic solvents were tested for interfering in assay, since samples collection and extraction is a necessary part in samples processing. Isopropanol was found as the most convenient due to minimal inhibition not exceeding 5%. Though all analysed pesticides inhibit AChE in vivo, some of them are toxic after metabolisation. We found AChE based assay approachable for assay of DFP, paraoxons, and dichlorvos. These are oxoforms of organophosphorus pesticides. From thioforms of assayed pesticides, only fenthion was able significantly inhibit AChE in vitro. ...

Organophosphorus (OP) based pesticides are known powerful inhibitors of cholinesterases, thus the toxicity of this class of compounds causes serious environmental and human health concerns. We report that benzodipyrido[3,2-a:2′,3′-c]phenazine (BDPPZ) and 3,6-dimethylbenzodipyrido-[3,2-a:2′,3′-c]phenazine (DM-BDPPZ) provide independent fluorescent and electrochemical signal transductions in the presence of the organophosphorus (OP) pesticides; fenthion, malathion and ethion. The presence of the methyl groups at the 3 and 6 positions in DM-BDPPZ was found to significantly influence the sensor performance. The difference in the fluorescence and electrochemical signals produced by the interaction of the sensor compound with each of the OP pesticides provides a means for differentiating between the three pesticides. Detection limits of 10 −8 M, 10 −9 and 10 −12 M were obtained for fenthion, malathion and ethion, respectively. Due to the high sensitivity and ability to minimize false positives these new sensors will be useful for potential integration for future environmental use.

Bovine milk spiked with seven organophosphorus pesticides, i.e., dimethoate, fenthion, malathion, methyl parathion, monocrotophos, phorate and trichlorphon, was fermented at 42?C with commercial directed vat set (DVS) starters to investigate the degradation kinetics of the pesticides during yoghurt processing. The spiked pesticides were extracted from the prepared samples with an organic solvent and analyzed by gas chromatography after purification. Based on published results that the degradation kinetics of pesticides is first order, the rate constant of degradation and the half live period of the pesticides were calculated. The results indicated that degradation of the pesticides in milk during yoghurt processing were enhanced by one or both starters, except for malathion, and the two commercial DVS starters had different influences on the degradation kinetics of the pesticides.

Organophosphate (OP) pesticides are used in agriculture in order to raise crop production. The aim of this study was to investigate the biological effects of two OPs, fenthion, and dimethoate, among 270 farm workers in the area of Agrinion (Western Greece) by measuring the serum butyrylcholinesterase (BChE) activity during the years 2004–2006. The BChE activity was photometrically analyzed before and after exposing to OP. Results showed that (1) the median BChE activity was reduced in the spraying period in comparison with the non-spraying period (7604 versus 9557 units L−1), (2) a significant difference in median pseudocholinesterase (PChE) activity was also observed between the two OPs (fenthion applicators −26.87%, dimethoate applicators −15.95%), (3) the duration of OP spraying influenced the mean BChE activity, which was −9.83% after 1 day, −23.81% after 2–3 days, and −25.26% after 4–7 days of spraying, (4) reduced levels of the mean value of PChE activity was observed in occupational applicators in ...

We have investigated the optical and electrochemical changes of the azastilbene, dimethyl-[4-(2-quinolin-2-yl-vinyl)-phenyl]-amine (DQA), with four organothiophosphorus (OTP) pesticides: ethion, malathion, parathion, and fenthion. Significant changes in UV–visible absorbance wavelength and in electrochemical signals indicate the effectiveness of DQA as an OTP sensor.

Culex quinquefasciatus is a domestic mosquito known as a primary vector of lymphatic filariasis. We report the development of insecticide resistance in four populations of C. quinquefasciatus Say, 1823 in Jodhpur (JD), Bikaner (BKN), Jamnagar (JMN) and Bathinda (BTH) in India in comparison to a susceptible laboratory population against larvicides such as temephos, fenthion, Bacillus thuringiensis var. israelensis and Neemarin (azadirachtin), and adulticides such as cypermethrin, alpha cypermethrin and lambda cyhalothrin. The resistance ratio (RR) at LC50 between field and laboratory populations was used for resistance expression. JD strain showed 10.8-, 6.94-, 5.29- and 2.82-fold resistance to temephos, fenthion, Neemarin and cypermethrin, respectively. BTH strain showed resistance to temephos, fenthion, lambda cyhalothrin, alpha cypermethrin and cypermethrin (9.06-, 2.06-, 3.33-, 4.96- and 3.19-fold, respectively). RR of BKN strain to temephos, fenthion, Neemarin and alpha cypermethrin was 5.17-, 4.12-, 4.33- and 3.04-fold, respectively; however RR was least in the JMN strain against most insecticides except alpha cypermethrin and fenthion. This study suggests that B. thuringiensis var israelensis and Neemarin may be efficient for larval control as an alternative to fenthion- and temephos-resistant strains of C. quinquefasciatus while lambda cyhalothrin and cypermethrin may be used effectively as an adulticide of this mosquito.

In this study the occurrence and levels of multi-class pesticides in different types of virgin olive oil quality and origination were determined and the contribution of olive oil in the chronic risk of pesticide residues consumption in the Mediterranean diet was estimated. For this purpose, a multiresidue method for the determination of 35 pesticides in olive oil was evaluated and applied to a total number of 100 olive oil samples. Ten percent of the samples produced from fruits of conventional cultivations contained no detectable residues whereas in the rest samples were detected residues of 20 insecticides. The highest detection rates were observed for the residues of fenthion, dimethoate and endosulfan. The highest occurrence and levels of pesticides were observed in extra virgin olive oil whereas results pointed that residues in olive oil from variety of olives with high oil yield may be higher. Furthermore, olive oil from organic cultivations could be contaminated with pesticide residues and/or contain low levels of pesticide residues that are not registered for use in olive cultivations. For there were multiresidues of pesticides present in olive oil, there is no zero risk in consumption of olive oil. However, the exposure of olive oil consumers to each detected residue is far below the acceptable daily intake (ADI).

A procedure for the determination of organophosphorous pesticides (OPPs) - phorate, diazinon, parathion-methyl, fenthion and quinalphos - in human urine was developed using the cloud point extraction of nonionic surfactant (Triton X-114) coupled with microwave-assisted back-extraction prior to gas chromatography with flame photometry detection (GC-FPD) analysis. The upper organic solution obtained from back-extraction was centrifugated simply for further cleanup for the sake of automatic injection. A preconcentration factor of 50 was obtained for these five OPPs extracted from only 10 mL of a sample. The limits of detection (LODs) were 0.07 ng mL(-1) for phorate, fenthion and quinalphos, 0.04 ng mL(-1) for diazinon and 0.08 ng mL(-1) for parathion-methyl. The limits of quantification (LOQs) were 0.21, 0.12, 0.24, 0.21 and 0.21 ng mL(-1), respectively. Accuracy of the method was evaluated by bias, which ranged from +6.85 to -14.68%. Precision was also good; the relative standard deviations (R.S.D.s) were less than 9%. The method showed to be potential for biological monitoring.

A method to effectively remove pigments in fresh vegetables using activated carbon followed cleanup through solid phase extraction (SPE) cartridge to further reduce matrix interference and contamination, was established to determine eight organophosphorous pesticides (OPPs) by gas chromatography (GC) with nitrogen-phosphorus detection (NPD) in this study, and it has been successfully applied for the determination of eight OPPs in various fresh vegetables with the recoveries ranging from 61.8% to 107%. To evaluate eight OPPs residue level, some fresh vegetables retailed at three agricultural product markets (APM) of Nanjing in China were detected, the results showed that phorate in Shanghai green (0.0257 microg g(-1)) and Chinese cabbage (0.0398 microg g(-1)), dimethoate in Shanghai green (0.0466-0.0810 microg g(-1)), Chinese cabbage (0.077 microg g(-1)), and spinach (0.118-0.124 microg g(-1)), methyl-parathion in Shanghai green (0.0903 microg g(-1)), Chinese cabbage (0.157 microg g(-1)), and spinach (0.0924 microg g(-1)), malathion in Shanghai green (0.0342-0.0526 microg g(-1)), chorpyrifos in spinach (0.106-0.204 microg g(-1)), and Chinese cabbage (0.149 microg g(-1)), chlorfenvinfos in carrot (0.094-0.131 microg g(-1)), were found. However, fonofos and fenthion were not detected in all the collected vegetable samples.

The present study was aimed at applying condition factor (CF), brain acetylcholinesterase (AChE) and gill histology as biomarkers for detecting possible exposure/effect induced by pesticides in fish residing rice field associated waterbodies in Sri Lanka. Biomarkers of an indigenous fish, Rasbora caverii collected from five sampling sites including canals near rice fields, a river and a reservoir (the reference site) were evaluated at four sampling stages covering pesticide application periods during rice cultivation season in 2004. Results indicated that CF of the fish did not show significant alterations regardless of the sampling sites or sampling stages. Site specific differences in AChE activities of the fish were not evident either prior to application of pesticides or at 7 days after Paraquat application to the rice fields. Two days after the application of a mixture of Fenthion and Phenthoate to the rice fields, AChE activity of the fish collected from canals near rice fields was significantly depressed (65-75%) compared to the fish in the reference site. The activities remain depressed to 50-56% even at 65 days after the insecticides application. Laboratory studies showed that prior exposure of R. caverii to Paraquat (2 microg l(-1), 7 days) enhanced the extent of inhibition of brain AChE activity induced by Fenthion (3 microg l(-1)) or a mixture of Fenthion (3 microg l(-1)) and Phenthoate (5 microg l(-1)). Gills of fish collected from canals near rice fields exhibited abnormal multiple divisions at the tips of some secondary lamellae in addition to hyperplasia, hypertrophy and club shaped deformities. Results indicate that application of pesticides in rice culture could manifest a threat to native fish populations residing rice field associated waterbodies. The response of brain AChE and histological changes in the gills of R. caverii allowed differentiating sampling sites after insecticide applications to the rice fields. Hence, R. caverii may be considered as a surrogate species in ecotoxicological risk evaluation of agrochemicals in the region.

This paper presents the toxicity data of seven pesticides including atrazine, parathion, dichlorvos, malathion, fenthion, 2-methyl-4-chlorophenoxyacetic acid, and pentachlorophenol on Pseudokirchneriella subcapitata based on a new algal toxicity testing technique conducted under air-tight environment. The dissolved oxygen production and the cell density were adopted as the response endpoints. Median effective concentrations (EC50) range from 0.0035 to 3.40 mg/L (DO production) and from 0.0067 to 3.12 mg/L (cell density). No-observed-effect concentration (NOEC) was determined using the Dunnett's test. NOEC values are with in the range of 0.001-1.20 mg/L. In general, the two test endpoints revealed similar sensitivities. From comparisons of literature data also based on Pseudokirchneriella subcapitata, it is clear that conventional batch tests tend to underestimate the toxicity of pesticides due to their open test environment. Closed-system tests, i.e., microplate test, respirometer test, and our BOD-bottle test, generally provide better assessment to the effects of pesticides. Data based on our test method reveals much higher toxicity (3-100 times) than that from the conventional batch tests. Furthermore, for organophosphorus insecticides, results from the present study show that Pseudokirchneriella subcapitata is less sensitive than Daphnia magna and rainbow trout, but is more susceptible than fathead minnow. The closed-system test applied in this study provides more adequate assessment for the toxicity of pesticides than the conventional batch tests.