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Chemosphere Sep 2016Insecticide resistance is usually associated with pests, but may also evolve in natural enemies. In this study, adult beetles of three distinct North American...
Insecticide resistance is usually associated with pests, but may also evolve in natural enemies. In this study, adult beetles of three distinct North American populations of Hippodamia convergens Guérin-Méneville, and the progeny of reciprocal crosses between the resistant and most susceptible population, were treated topically with varying concentrations of lambda-cyhalothrin and dicrotophos. In addition, the LD50s of both insecticides were applied in combination to resistant individuals. The developmental and reproductive performance of each population was assessed in the absence of insecticide exposure to compare baseline fitness. California and Kansas populations were susceptible to both materials, whereas Georgia (GA) beetles exhibited a resistance ratio (RR50) of 158 to lambda-cyhalothrin and 530 to dicrotophos. Inheritance of lambda-cyhalothrin resistance was X-linked, whereas inheritance of dicrotophos resistance was autosomal. Mortality of resistant beetles treated with a mixture of LD50s of both materials was twice that of those treated with lambda-cyhalothrin alone, but not significantly different from those receiving dicrotophos alone. Life history parameters were largely similar among populations, except that Georgia beetles had higher egg fertility relative to susceptible populations. We conclude that the high levels of resistance to lambda-cyhalothrin and dicrotophos in Georgia beetles reflect heavy loads of these insecticides in local environments, most likely the large acreage under intensive cotton cultivation.
Topics: Animals; California; Coleoptera; Female; Fertility; Georgia; Insecticide Resistance; Insecticides; Kansas; Male; Nitriles; Organophosphorus Compounds; Pyrethrins
PubMed: 27266835
DOI: 10.1016/j.chemosphere.2016.05.075 -
International Journal of Clinical and... 2015Organophosphorus compound poisoning (OPC) is a global issue. The problem is aggravated with the threats of terrorist use, unintentional use and irresponsible practice as...
Organophosphorus compound poisoning (OPC) is a global issue. The problem is aggravated with the threats of terrorist use, unintentional use and irresponsible practice as happened recently in turmoil countries. The purpose of the current study was to investigate the old-generation antihistamine promethazine (PROM), a drug with multi pharmacological actions, as an antidote to extremely and highly toxic (WHO's class IA and IB) OPC poisoning in experimental animal models conducted on adult male wistar rats. Experimental groups were treated intraperitoneal (i.p.) with LD70 of methyl paraoxon (MPOX), class IA and dicrotophos (DCP), class IB alone and a combination of simultaneously i.p. injection of PROM. Mortality was recorded at 30 minutes, 1, 2, 3, 4, 24, 48 hours post injections. RBC-AChE was measured in survivals. MPOX was chosen for further studies with atropine (ATR) and pralidoxime (PAM). In addition to Kaplan-Meir survival analysis, serum lactate dehydrogenase (LDH) and creatinine kinase (CK) from serum were measured in all experimental groups with MPOX. The results revealed significant protection by PROM in both MPOX and DCP intoxicated rats, though the inhibition of RBC-AChE was high. The observed results show that groups treated with a combination of MPOX and PROM or MPOX, PROM, and PAM were protected higher than those treated with MPOX and ATR or MPOX, ATR, and PAM though statistically not significantly different (P ≤ 0.05). No effect was observed on the activity of LDH and CK. The study concludes that PROM may be effectively used in OPC poisoning. However, risk/benefits trials and further studies with different doses and other OPC groups are warranted.
PubMed: 26770383
DOI: No ID Found -
Analytical Sciences : the International... 2017The overuse of organophosphorus pesticides on cotton production is a big concern in China today. Therefore, developing methods for the rapid screening and confirming of...
The overuse of organophosphorus pesticides on cotton production is a big concern in China today. Therefore, developing methods for the rapid screening and confirming of pesticide residues in textiles has become a top public health security priority. Here, a method was established for the rapid screening and quantifying of 11 kinds of organophosphorus pesticides (ethoprophos, coumaphos, profenofos, diazinon, ethion, parathion, phosalone, quinalphos, dicrotophos, azinphos methyl, and tribuphos) in textiles by high-performance liquid chromatography high-resolution mass spectrometry (HPLC-HRMS). Rapid screening and quantifying could be completed by using software of Peakview and MultiQuant. Samples were extracted by the method of modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and analyzed in the positive mode with MS detection. The results showed that the limits of detection were between 0.1 and 5.0 ng g, with correlation coefficients above 0.9990. The recoveries were in the range of 70.3 - 109.8%, with relative standard deviations from 5.1 to 16.4%. This method is accurate and simple, which can be used in the rapid screening and quantitative analysis of 11 kinds of organophosphorus pesticides in textiles.
PubMed: 28890486
DOI: 10.2116/analsci.33.1027 -
The Science of the Total Environment Nov 2020During water years (WY) 2013-2017, the U.S. Geological Survey, National Water-Quality Assessment (NAWQA) Project, sampled the National Water Quality Network - Rivers and...
During water years (WY) 2013-2017, the U.S. Geological Survey, National Water-Quality Assessment (NAWQA) Project, sampled the National Water Quality Network - Rivers and Streams (NWQN) year-round and reported on 221 pesticides at 72 sites across the United States in agricultural, developed, and mixed land use watersheds. The Pesticide Toxicity Index (PTI) was used to estimate the potential chronic and acute toxicity to three taxonomic groups - fish, cladocerans, and benthic invertebrates. For invertebrates (either cladocerans, benthic invertebrates, or both), the maximum PTI score exceeded the predicted acute toxicity screening level at 18 of the 72 sites (25%) at some point during WY 2013-2017. The predicted toxicity of a single pesticide compound was found to overwhelm the toxicity of other pesticides in the mixtures after concentrations were toxicity weighted. For this study, about 71%, 72%, and 92% of the Fish-, Cladoceran-, and Benthic Invertebrate-PTI scores, respectively, had one pesticide compound primarily contributing to sample potential toxicity (>50%). There were 17 (13 insecticides, 2 herbicides, 1 fungicide, and 1 synergist) of the 221 pesticide compounds analyzed that were the primary drivers of potential toxicity in each water sample in which the PTI and TUmax (toxic unit score for the pesticide that makes the single largest contribution to the PTI) scores were above predicted chronic (>0.1) or acute (>1) toxicity levels for one of the three taxa. For cladocerans and benthic invertebrates, the drivers of predicted chronic (>0.1) and acute (>1) PTIs were mostly insecticides. For cladocerans, the pesticide compounds driving the PTI scores were bifenthrin, carbaryl, chlorpyrifos, diazinon, dichlorvos, dicrotophos, diflubenzuron, flubendiamide, and tebupirimfos. For benthic invertebrates, atrazine (an herbicide), as well as the insecticides - bifenthrin, carbaryl, carbofuran, chlorpyrifos, diazinon, dichlorvos, fipronil, imidacloprid, and methamidophos - were the drivers of predicted toxicity. For fish, there were three pesticide types that contributed the most to predicted chronic (>0.1) PTIs - acetochlor, an herbicide; carbendazim, a fungicide degradate; and piperonylbutoxide, a synergist.
Topics: Animals; Environmental Monitoring; Pesticides; Rivers; United States; Water; Water Pollutants, Chemical
PubMed: 32943215
DOI: 10.1016/j.scitotenv.2020.141285 -
Journal of Economic Entomology Oct 2022Foliar-applied insecticide treatments may be necessary to manage thrips in cotton (Gossypium hirsutum L.) under severe infestations or when at-planting insecticide seed...
Foliar-applied insecticide treatments may be necessary to manage thrips in cotton (Gossypium hirsutum L.) under severe infestations or when at-planting insecticide seed treatments do not provide satisfactory protection. The most common foliar-applied insecticide is acephate. Field observations in Tennessee suggest that the performance of acephate has declined. Thus, the first objective was to perform leaf-dip bioassays to assess if tobacco thrips, Frankliniella fusca (Hinds) (Thysanoptera: Thripidae), in cotton production regions have evolved resistance to foliar-applied insecticides. A second objective was to assess the performance of commonly applied foliar insecticides for managing thrips in standardized field trials in Arkansas, Tennessee, Mississippi, and Texas. For both objectives, several insecticides were evaluated including acephate, dicrotophos, dimethoate, lambda-cyhalothrin, imidacloprid, and spinetoram. Field trials and bioassays were completed from 2018 to 2021. Dose-response bioassays with acephate were performed on tobacco thrips field populations and a susceptible laboratory population. Bioassay results suggest that tobacco thrips have developed resistance to acephate and other organophosphate insecticides; however, this resistance seems to be most severe in Arkansas, Tennessee, and the Delta region of Mississippi. Resistance to other classes of insecticides were perhaps even more evident in these bioassays. The performance of these insecticides in field trials was variable, with tobacco thrips only showing consistent signs of resistance to lambda-cyhalothrin. However, it is evident that many populations of tobacco thrips are resistant to multiple classes of insecticides. Further research is needed to determine heritability and resistance mechanism(s).
Topics: Animals; Biological Assay; Dimethoate; Gossypium; Insecticides; Nitriles; Organothiophosphorus Compounds; Phosphoramides; Pyrethrins; Thysanoptera; Nicotiana; United States
PubMed: 36099406
DOI: 10.1093/jee/toac136 -
Canadian Journal of Comparative... Jan 1978Ten day old chick sympathetic ganglia cultured in a microslide assembly were treated with a selected group of organophosphate pesticides to evaluate their cytotoxicity...
Ten day old chick sympathetic ganglia cultured in a microslide assembly were treated with a selected group of organophosphate pesticides to evaluate their cytotoxicity ranges, and the usefulness of such a model for screening pesticides. Examination by phase contrast and light microscopy for chemically-induced morphological alteration of nerve fibers, glial cells and neurons provided the criteria for quantitation and assessment of the toxic effects. Concentrations that produced half-maximal effects ranged from 1 x 10(-6)M (severely toxic) for methylparathian, diazinon, paraoxon, mevinphos, diisopropylfluorophosphate, tri-o-tolyl phosphate and its mixed isomers to a 1 x 10(-3)M (intermediate) for malathion, leptophos, coumaphos, mono- and dicrotophos. Some or no effects were evident at 1 x 10(2-)M for O'ethyl-O-p-nitrophenyl phenyl phosphonothioate, tri-m-tolylphosphate, chlorpyriphos and triphenyl phosphate. In all instances, nerve fibers were more sensitive than neurons or glial cells to insecticides. All cellular growth was inhibited at 1 x 10(-2)M (except triphenyl phosphate). Below 1 x 10(-7)M, no inhibitory effects were evident. The secondary abnormalities included decreased cellular migration, diffuse cellular growth pattern, increased vacuolization, nerve fiber swelling and cellular degeneration. The cytotoxic effects of these chemicals do not appear to be related to in vivo toxicity or cholinesterase inhibition potential.
Topics: Animals; Chick Embryo; Dose-Response Relationship, Drug; Ganglia, Autonomic; Insecticides; Organophosphorus Compounds; Organothiophosphorus Compounds
PubMed: 565668
DOI: No ID Found -
Journal of Environmental and Public... 2009This study investigated inhalation exposure to organophosphate pesticides (OPPs) and evaluated the associated health risks to vegetable growers living in the Bang-Rieng...
This study investigated inhalation exposure to organophosphate pesticides (OPPs) and evaluated the associated health risks to vegetable growers living in the Bang-Rieng agricultural community. Air samples were collected by using personal sampling pumps with sorbent tubes placed in the vegetable growers' breathing zone. Samples were collected during both wet and dry seasons. Residues of organophosphate pesticides, that is, chlorpyrifos, dicrotofos, and profenofos, were analyzed from 33 vegetable growers and 17 reference subjects. Results showed that median concentrations of OPPs in air in farm areas were in the range of 0.022-0.056 mg/m(3) and air in nonfarm areas in the range of <0.0016-<0.005 mg/m(3). The concentration of the three pesticides in the vegetable growers was significantly higher than that of the references during both seasons. The results also indicate that the vegetable growers may be at risk for acute adverse effects via the inhalation of chlorpyrifos and dicrotofos during pesticide application, mixing, loading, and spraying. It is suggested that authorities and the community should implement appropriate strategies concerning risk reduction and risk management.
Topics: Adult; Agriculture; Air; Air Pollutants, Occupational; Chlorpyrifos; Cross-Sectional Studies; Female; Humans; Inhalation Exposure; Male; Occupational Exposure; Organophosphates; Organophosphorus Compounds; Organothiophosphates; Pesticides; Risk; Thailand; Vegetables
PubMed: 20168980
DOI: 10.1155/2009/452373 -
Quantitative studies of the effect of antagonists on the acute toxicity of organophosphates in rats.British Journal of Pharmacology Sep 19701. The subcutaneous acute toxicities of the vinyl phosphate pesticides monocrotophos, dicrotophos, chlorfenvinphos, crotoxyphos, dichlorvos, mevinphos, and of the...
1. The subcutaneous acute toxicities of the vinyl phosphate pesticides monocrotophos, dicrotophos, chlorfenvinphos, crotoxyphos, dichlorvos, mevinphos, and of the experimental compounds SD 4455 (cis-2-carboxy-1-methylvinyl dimethylphosphate) and SD 7779 (cis-2-(1-phenylethoxy) carbonyl-1-methylvinyl diethylphosphate) have been determined in female rats.2. The effects on the log dose-probit mortality curves to the vinylphosphates of the therapeutic subcutaneous administration of methylatropine, atropine, N-methylpyridinium-2-aldoxime methanesulphonate and obidoxime have been studied.3. Elevation of the LD50 values by the therapeutic regimens was shown to be an unsatisfactory measure of therapeutic efficiency, while reduction of the effect of a maximally lethal dose (LD90) to less than that of a minimally lethal dose (LD10) provided a better quantitative measure of therapeutic efficiency.4. The combination of atropine sulphate (50 mumol base/kg) with obidoxime (250 mumol/kg) was found to be generally the most effective of the antidotal regimens.
Topics: Alkenes; Animals; Antidotes; Atropine; Drug Synergism; Female; Oximes; Pesticides; Phosphoric Acids; Pyridinium Compounds; Rats; Sulfonic Acids
PubMed: 5487002
DOI: 10.1111/j.1476-5381.1970.tb10617.x