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Journal of Economic Entomology May 2018Peanut growers use a combination of tactics to manage spotted wilt disease caused by thrips-transmitted Tomato spotted wilt virus (TSWV). They include planting...
Evaluation of Alternatives to an Organophosphate Insecticide with Selected Cultural Practices: Effects on Thrips, Frankliniella fusca, and Incidence of Spotted Wilt in Peanut Farmscapes.
Peanut growers use a combination of tactics to manage spotted wilt disease caused by thrips-transmitted Tomato spotted wilt virus (TSWV). They include planting TSWV-resistant cultivars, application of insecticides, and various cultural practices. Two commonly used insecticides against thrips are aldicarb and phorate. Both insecticides exhibit broad-spectrum toxicity. Recent research has led to the identification of potential alternatives to aldicarb and phorate. In this study, along with reduced-risk, alternative insecticides, we evaluated the effect of conventional versus strip tillage; single versus twin row seeding pattern; and 13 seed/m versus 20 seed/m on thips density, feeding injury, and spotted wilt incidence. Three field trials were conducted in Georgia in 2012 and 2013. Thrips counts, thrips feeding injuriy, and incidence of spotted wilt were less under strip tillage than under conventional tillage. Reduced feeding injury from thrips was observed on twin-row plots compared with single-row plots. Thrips counts, thrips feeding injury, and incidence of spotted wilt did not vary by seeding rate. Yield from twin-row plots was greater than yield from single-row plots only in 2012. Yield was not affected by other cultural practices. Alternative insecticides, including imidacloprid and spinetoram, were as effective as phorate in suppressing thrips and reducing incidence of spotted wilt in conjunction with cultural practices. Results suggest that cultural practices and reduced-risk insecticides (alternatives to aldicarb and phorate) can effectively suppress thrips and incidence of spotted wilt in peanut.
Topics: Animals; Arachis; Crop Production; Georgia; Insect Control; Insecticides; Macrolides; Neonicotinoids; Plant Diseases; Thysanoptera; Tospovirus
PubMed: 29635299
DOI: 10.1093/jee/toy079 -
Analytical and Bioanalytical Chemistry May 2018Baby foods are either a soft, liquid paste or an easily chewed food since babies lack developed muscles and teeth to chew effectively. Babies typically move to consuming...
Baby foods are either a soft, liquid paste or an easily chewed food since babies lack developed muscles and teeth to chew effectively. Babies typically move to consuming baby food once nursing or formula is not sufficient for the child's appetite. Some commercial baby foods have been criticized for their contents. This article focuses on the simultaneous determination of organophosphorus pesticides and phthalates by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap mass spectrometry (GC-IT/MS). The protocol developed allowed the determination of six phthalates [dimethyl phthalate, diethyl phthalate, dibutyl phthalate, isobutyl cyclohexyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate] and 19 organophosphorus pesticides. Freeze-dried product samples (0.1-0.2 g) were dissolved in 10 mL of warm distilled water along with 5 μL of an internal standard (anthracene at 10 mg mL in acetone): the choice of extraction solvent was studied, with the most suitable being n-heptane, which is used for phthalate determination in similar matrices. The solution, held for 5 min in a vortex mixer and for 6 min in a 100-W ultrasonic bath to favor solvent dispersion and consequently analyte extraction, was centrifuged at 4000 rpm for 30 min. Then 1 μL was injected into the GC-IT/MS system (SE-54 capillary column; length 30 m, inner diameter 250 μm, film thickness 0.25 μm). All analytical parameters investigated are discussed in depth. The method was applied to real commercial freeze-dried samples: significant contaminant concentrations were not found. Graphical abstract Simultaneous and sensitive determination of organophosphorus pesticides and phthalates in baby foods by the ultrasound-vortex-assisted liquid-liquid microextraction ֪gas chromatography-ion trap mass spectrometry procedure. 1 methacrifos, 2 pirofos, 3 phorate, 4 seraphos, 5 diazinon, 6 etrimphos, 7 dichlofenthion, 8 chlorpyrifos-methyl, 9 pirimiphos-methyl, 10 malathion, 11 chlorpyrifos, 12 parathion-ethyl, 13 pirimiphos-ethyl, 14 bromophos, 15 chlorfenvinphos, 16 bromophos-ethyl, 17 stirophos, 18 diethion, 19 coumaphos, A dimethyl phthalate, B diethyl phthalate, C dibutyl phthalate, D butyl cyclohexyl phthalate, E benzyl butyl phthalate, F bis(2-ethylhexyl) phthalate, IS internal standard.
Topics: Gas Chromatography-Mass Spectrometry; Humans; Infant Food; Infant, Newborn; Limit of Detection; Liquid Phase Microextraction; Organophosphorus Compounds; Pesticides; Phthalic Acids; Sonication
PubMed: 29549507
DOI: 10.1007/s00216-018-0986-x -
Pesticide Biochemistry and Physiology Feb 2018Phorate is a highly toxic agricultural pesticide currently in use throughout the world. Like many other organophosphorus (OP) pesticides, the primary mechanism of the...
Kinetic analysis of oxime-assisted reactivation of human, Guinea pig, and rat acetylcholinesterase inhibited by the organophosphorus pesticide metabolite phorate oxon (PHO).
UNLABELLED
Phorate is a highly toxic agricultural pesticide currently in use throughout the world. Like many other organophosphorus (OP) pesticides, the primary mechanism of the acute toxicity of phorate is acetylcholinesterase (AChE) inhibition mediated by its bioactivated oxon metabolite. AChE reactivation is a critical aspect in the treatment of acute OP intoxication. Unfortunately, very little is currently known about the capacity of various oximes to rescue phorate oxon (PHO)-inhibited AChE. To help fill this knowledge gap, we evaluated the kinetics of inhibition, reactivation, and aging of PHO using recombinant AChE derived from three species (rat, guinea pig and human) commonly utilized to study the toxicity of OP compounds and five oximes that are currently fielded (or have been deemed extremely promising) as anti-OP therapies by various nations around the globe: 2-PAM Cl, HI-6 DMS, obidoxime Cl, MMB4-DMS, and HLö7 DMS. The inhibition rate constants (k) for PHO were calculated for AChE derived from each species and found to be low (i.e., 4.8×10 to 1.4×10Mmin) compared to many other OPs. Obidoxime Cl was the most effective reactivator tested. The aging rate of PHO-inhibited AChE was very slow (limited aging was observed out to 48h) for all three species.
CONCLUSIONS
(1) Obidoxime Cl was the most effective reactivator tested. (2) 2-PAM Cl, showed limited effectiveness in reactivating PHO-inhibited AChE, suggesting that it may have limited usefulness in the clinical management of acute PHO intoxication. (3) The therapeutic window for oxime administration following exposure to phorate (or PHO) is not limited by aging.
Topics: Acetylcholinesterase; Animals; Antidotes; Cholinesterase Inhibitors; Cholinesterase Reactivators; Guinea Pigs; Humans; Kinetics; Obidoxime Chloride; Oximes; Pesticides; Phorate; Rats
PubMed: 29482737
DOI: 10.1016/j.pestbp.2018.01.009 -
International Journal of Hygiene and... Apr 2018Occupational studies suggest that exposure to organophosphate insecticides (OPs) can lead to vision or hearing loss. Yet the effects of early-life exposure on visual and...
BACKGROUND
Occupational studies suggest that exposure to organophosphate insecticides (OPs) can lead to vision or hearing loss. Yet the effects of early-life exposure on visual and auditory function are unknown. Here we examined associations between prenatal OP exposure and grating visual acuity (VA) and auditory brainstem response (ABR) during infancy.
METHODS
30 OPs were measured in umbilical cord blood using gas chromatography tandem mass spectrometry in a cohort of Chinese infants. Grating visual acuity (VA) (n = 179-200) and auditory brainstem response (ABR) (n = 139-183) were assessed at 6 weeks, 9 months, and 18 months. Outcomes included VA score, ABR wave V latency and central conduction time, and head circumference (HC). Associations between sensory outcomes during infancy and cord OPs were examined using linear mixed models.
RESULTS
Prenatal chlorpyrifos exposure was associated with lower 9-month grating VA scores; scores were 0.64 (95% CI: -1.22, -0.06) points lower for exposed versus unexposed infants (p = 0.03). The OPs examined were not associated with infant ABR latencies, but chlorpyrifos and phorate were both significantly inversely associated with HC at 9 months; HCs were 0.41 (95% CI: 0.75, 0.6) cm and 0.44 (95% CI: 0.88, 0.1) cm smaller for chlorpyrifos (p = 0.02) and phorate (p = 0.04), respectively.
CONCLUSIONS
We found deficits in grating VA and HC in 9-month-old infants with prenatal exposure to chlorpyrifos. The clinical significance of these small but statistically significant deficits is unclear. However, the disruption of visual or auditory pathway maturation in infancy could potentially negatively affect downstream cognitive development.
Topics: Adult; Chlorpyrifos; Cohort Studies; Developmental Disabilities; Environmental Pollutants; Evoked Potentials, Auditory, Brain Stem; Female; Fetal Blood; Hearing; Hearing Disorders; Humans; Infant; Insecticides; Male; Maternal Exposure; Mothers; Organophosphorus Compounds; Phorate; Pregnancy; Prenatal Exposure Delayed Effects; Sensation; Vision Disorders; Vision, Ocular; Visual Acuity
PubMed: 29402694
DOI: 10.1016/j.ijheh.2018.01.010 -
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing... Jul 2017To observe the therapeutic efficacy of alanyl glutamine injection on patients with gastrointestinal function obstacle caused by severe phorate poisoning. A total of 80... (Randomized Controlled Trial)
Randomized Controlled Trial
To observe the therapeutic efficacy of alanyl glutamine injection on patients with gastrointestinal function obstacle caused by severe phorate poisoning. A total of 80 eligible patients with gastrointestinal function obstacle caused by severe phorate poisoning were randomly divided into the control group (=40) and treatment group (=40) . The control group was treated with the conventional therapy, which included forbidden diet, atropine, pralidoxime iodide, anti-inflammatory, albumin infusion, ω-3 fish oil fat emulsion, protection of organs function, blood perfusion, and Fat Emulsion, Amino Acids (17) and Glucose Injection. The treatment group was treated with alanyl glutamine injection plus the conventional therapy. To observe the time of recovering to normal of gastrointestinal function between the two groups, compared the AChE activity and changes of prealbumin, albumin and total protein of the two groups respectively. Furthermore, the total atropine dosage, the total pralidoxime iodide dosage and ICU stay time between the two groups were also compared. The gastrointestinal function recovery time of patients in the treatment group was less than the control group, the difference was statistically significant (<0.05) . From the third day of treatment, the serum cholinesterase activity of the treatment group was higher than the control group, the difference was statistically significant (<0.05) . On the 5th day and 10th day of the treatment, the prealbumin, albumin and total protein of the treatment group were significantly higher than these indexes of the control group in the same period, the difference were statistically significant (<0.05) . The total atropine dosage, the total pralidoxime iodide dosage and ICU stay time in the treatment group were lower than the control group, the difference were statistically significant (<0.05) . Alanyl glutamine injection has a great therapeutic effect for gastrointestinal function obstacle patients caused by severe phorate poisoning.
Topics: Atropine; Glutamine; Humans; Insecticides; Intestinal Obstruction; Organophosphate Poisoning; Phorate; Severity of Illness Index; Treatment Outcome
PubMed: 29081098
DOI: 10.3760/cma.j.issn.1001-9391.2017.07.006 -
Environmental Health Perspectives Jul 2017Age-related macular degeneration (AMD) is a leading cause of blindness in developed countries. Few studies have investigated its relationship to environmental...
BACKGROUND
Age-related macular degeneration (AMD) is a leading cause of blindness in developed countries. Few studies have investigated its relationship to environmental neurotoxicants. In previous cross-sectional studies, we found an association between pesticide use and self-reported retinal degeneration.
OBJECTIVE
We evaluated the association of pesticide use with physician-confirmed incident AMD.
METHODS
The Agricultural Health Study (AHS) is a prospective cohort of pesticide applicators and their spouses enrolled from 1993-1997 in Iowa and North Carolina. Cohort members reported lifetime use of 50 specific pesticides at enrollment. Self-reports of incident AMD during follow-up through 2007 were confirmed by reports from participants' physicians and by independent evaluation of retinal photographs provided by the physicians. Confirmed cases (=161) were compared with AHS cohort members without AMD (=39,108). We estimated odds ratios (ORs) and 95% confidence intervals (CIs) by logistic regression with adjustment for age, gender, and smoking.
RESULTS
AMD was associated with ever use of organochlorine [OR=2.7 (95% CI: 1.8, 4.0)] and organophosphate [OR=2.0 (95% CI: 1.3, 3.0)] insecticides and phenoxyacetate herbicides [OR=1.9 (95% CI: 1.2, 2.8)]. Specific pesticides consistently associated with AMD included chlordane, dichlorodiphenyltrichloroethane (DDT), malathion, and captan; others with notable but slightly less consistent associations were heptachlor, diazinon, phorate, 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), and 2,4-dichlorophenoxyacetic acid (2,4-D). Results were similar for men and women. Some specific pesticides were associated with both early- and late-stage AMD, but others were associated with only one stage.
CONCLUSIONS
Exposures to specific pesticides may be modifiable risk factors for AMD. https://doi.org/10.1289/EHP793.
Topics: Aged; Aged, 80 and over; Agricultural Workers' Diseases; Case-Control Studies; Female; Humans; Incidence; Iowa; Logistic Models; Macular Degeneration; Male; Middle Aged; North Carolina; Occupational Exposure; Pesticides; Prospective Studies; Risk Factors
PubMed: 28886597
DOI: 10.1289/EHP793 -
Food Chemistry Dec 2017Due the negative effects of pesticides on environment and human health, more efficient and environmentally friendly methods are needed. In this sense, a simple, fast,...
Due the negative effects of pesticides on environment and human health, more efficient and environmentally friendly methods are needed. In this sense, a simple, fast, free from memory effects and economical direct-immersion single drop micro-extraction (SDME) method and GC-MS for multi-class pesticides determination in mango samples was developed. Sample pre-treatment using ultrasound-assisted solvent extraction and factors affecting the SDME procedure (extractant solvent, drop volume, stirring rate, ionic strength, time, pH and temperature) were optimized using factorial experimental design. This method presented high sensitive (LOD: 0.14-169.20μgkg), acceptable precision (RSD: 0.7-19.1%), satisfactory recovery (69-119%) and high enrichment factors (20-722). Several obtained LOQs are below the MRLs established by the European Commission; therefore, the method could be applied for pesticides determination in routing analysis and custom laboratories. Moreover, this method has shown to be suitable for determination of some of the studied pesticides in lime, melon, papaya, banana, tomato, and lettuce.
Topics: Gas Chromatography-Mass Spectrometry; Lactuca; Mangifera; Pesticides
PubMed: 28764000
DOI: 10.1016/j.foodchem.2017.05.030 -
Environment International Sep 2017Organophosphate insecticides (OPs) are used worldwide, yet despite nearly ubiquitous exposure in the general population, few have been studied outside the laboratory....
BACKGROUND
Organophosphate insecticides (OPs) are used worldwide, yet despite nearly ubiquitous exposure in the general population, few have been studied outside the laboratory. Fetal brains undergo rapid growth and development, leaving them susceptible to long-term effects of neurotoxic OPs. The objective here was to investigate the extent to which prenatal exposure to OPs affects infant motor development.
METHODS
30 OPs were measured in umbilical cord blood using gas chromatography tandem mass spectrometry in a cohort of Chinese infants. Motor function was assessed at 6-weeks and 9-months using Peabody Developmental Motor Scales 2nd edition (PDMS-2) (n=199). Outcomes included subtest scores: reflexes, stationary, locomotion, grasping, visual-motor integration (V-M), composite scores: gross (GM), fine (FM), total motor (TM), and standardized motor quotients: gross (GMQ), fine (FMQ), total motor (TMQ).
RESULTS
Naled, methamidophos, trichlorfon, chlorpyrifos, and phorate were detected in ≥10% of samples. Prenatal naled and chlorpyrifos were associated with decreased 9-month motor function. Scores were 0.55, 0.85, and 0.90 points lower per 1ng/mL increase in log-naled, for V-M (p=0.04), FM (p=0.04), and FMQ (p=0.08), respectively. For chlorpyrifos, scores were 0.50, 1.98, 0.80, 1.91, 3.49, 2.71, 6.29, 2.56, 2.04, and 2.59 points lower for exposed versus unexposed infants, for reflexes (p=0.04), locomotion (p=0.02), grasping (p=0.05), V-M (p<0.001), GM (p=0.007), FM (p=0.002), TM (p<0.001), GMQ (p=0.01), FMQ (p=0.07), and TMQ (p=0.008), respectively. Girls appeared to be more sensitive to the negative effects of OPs on 9-month motor function than boys.
CONCLUSIONS
We found deficits in 9-month motor function in infants with prenatal exposure to naled and chlorpyrifos. Naled is being aerially sprayed to combat mosquitoes carrying Zika virus, yet this is the first non-occupational human study of its health effects. Delays in early-motor skill acquisition may be detrimental for downstream development and cognition.
Topics: China; Chlorpyrifos; Cohort Studies; Developmental Disabilities; Female; Fetal Blood; Humans; Infant; Infant, Newborn; Insecticides; Male; Motor Skills; Naled; Pregnancy; Prenatal Exposure Delayed Effects
PubMed: 28602489
DOI: 10.1016/j.envint.2017.05.015 -
Chemosphere Sep 2017The present study was conducted to assess the in-vivo activities of certain molecular biomarkers under the impact of phorate exposure. Fish, Channa punctatus...
The present study was conducted to assess the in-vivo activities of certain molecular biomarkers under the impact of phorate exposure. Fish, Channa punctatus (35 ± 3.0 g; 14.5 ± 1.0 cm; Actinopterygii) were subjected to semi-static conditions having 5% (0.0375 mg/L for T1 group) and 10% of 96 h-LC (0.075 mg/L for T2 group) of phorate exposure for 15 and 30 d. The oxidative stress was assessed in terms of superoxide dismutase (SOD) and catalase (CAT) activities. DNA damage was measured as induction of micronuclei (MN) and consequent differential expression of apoptotic genes-tumor suppressor (p53), apoptotic peptidase activating factor-1 (apaf-1) and catalase (cat) in liver and kidney, two major sites of biotransformation in fish, were quantified. Our findings reveal significant (p < 0.001) augmentations in SOD and CAT activities of liver and kidney tissues. MN frequency in erythrocytes of fish also increases significantly (p < 0.05) in a dose- and time-dependent manner. The mRNA level of p53 increased significantly (p < 0.05) in liver at 10% of 96 h-LC of phorate exposure after 30 d suggesting generation of stress due to accumulation of reactive oxygen species (ROS). Eventually, these findings decipher the dual role of ROS in generating genotoxicity as is evident by micronuclei induction and differential regulation of p53, apaf-1 and cat genes during the phorate induced DNA damage and apoptosis in test fish. The experimental inferences drawn on the basis of activities of aforesaid biomarkers shall be helpful in elucidating the possible causes of apoptosis under stressful conditions. Further, this study finds ample application in biomonitoring of phorate polluted aquatic ecosystem.
Topics: Animals; Apoptotic Protease-Activating Factor 1; Catalase; Cholinesterase Inhibitors; DNA Damage; Fishes; Gene Expression Profiling; Kidney; Liver; Oxidative Stress; Perciformes; Phorate; Superoxide Dismutase; Tumor Suppressor Protein p53
PubMed: 28511133
DOI: 10.1016/j.chemosphere.2017.05.008 -
Food Chemistry Oct 2017This work presents the effects of pan cooking on PCBs, PCDD/Fs, pesticides and trace elements in meat from a risk assessment perspective. Three different realistic...
This work presents the effects of pan cooking on PCBs, PCDD/Fs, pesticides and trace elements in meat from a risk assessment perspective. Three different realistic cooking intensities were studied. A GC×GC-TOF/MS method was set up for the multiresidue analysis of 189 PCBs, 17 PCDD/Fs and 16 pesticides whereas Cd, As, Pb and Hg were assayed by ICP-MS. In terms of quantity, average PCB losses after cooking were 18±5% for rare, 30±3% for medium, and 48±2% for well-done meat. In contrast, average PCDD/F losses were not significant. For pesticides, no loss occurred for aldrin, lindane, DDE or DDD, whereas losses exceeding 80% were found for dieldrin, sulfotep or phorate. Losses close to the margin of error were observed for trace elements. These results are discussed in light of the physicochemical properties of the micropollutants as well as of water and fat losses into cooking juice.
Topics: Cooking; Food Handling; Hot Temperature; Meat; Polychlorinated Biphenyls
PubMed: 28490090
DOI: 10.1016/j.foodchem.2017.03.049