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The high susceptibility of harvested fresh fish to immediate deterioration has resulted in the fundamental need for fish preservation to maintain its nutritional quality, minimize changes in its physical appearance, taste and lengthen shelf life. The insecticide, pirimiphos methyl (actellic dust) has been utilized in the storage of dried products against insect infestation, thereby increasing their shelf life. This study investigated the effect of pirimiphos methyl on the proximate and mineral composition of Synodontis nigrita and Tilapia mariae in Jamieson River which were purchased from the fish landing site in Sapele Delta State, Nigeria. The fish samples were divided into three batches of fresh samples (batch I), oven – dried samples (batch II) and actellic dust treated samples (batch III). The proximate composition (moisture, protein, fat, ash, crude fibre, and carbohydrate) and mineral content (sodium, potassium, calcium, and magnesium) of the samples were determined using the AOAC standard methods. Results showed that actellic dust treatment greatly increased the protein (19.35 to 23.31%), fat (8.12% to 22.31%), and raw fibre content (0.69 to 8.03%) in S. nigrita and protein (7.09 to 25.46%), fat (5.13 to 11.70%), and raw fibre content (3.40 to 14.23%) in T. mariae. The mineral elements analyzed showed no well-defined order across the treatment levels with potassium being the most abundant mineral element in all fish samples. Actellic dust has been shown to improve the proximate composition and shelf life of both fish species studied, and its use as a fish preservative is therefore recommended.

The presence of pesticide residues in wheat grains and its products produced and imported in Algeria was determined using QuEchERS extraction method and multi-residue analysis by gas chromatography–mass spectrometry. Among the 80 wheat samples analysed, detectable residues were found in 62.5% of samples. The most often pesticide found was pirimiphos methyl in 46 samples (57.5%). A percentage of 5% of samples contained pesticide residues above Maximum Residue Limits (MRLs) due to benalaxyl, chlorpyrifos and metalaxyl residues. Risk assessment for long-term exposure was done for all pesticides detected in wheat grains, the risk of exposure of Algerian consumers to pirimiphos methyl residues through wheat consumption was potentially high (EDI = 78%ADI). This risk was less important in the case of chlorpyrifos (EDI<9% ADI). For the others residues, EDIs were less than 1.5% of ADIs. [ABSTRACT FROM AUTHOR]

The high susceptibility of harvested fresh fish to immediate deterioration has resulted in the fundamental need for fish preservation to maintain its nutritional quality, minimize changes in its physical appearance, taste and lengthen shelf life. The insecticide, pirimiphos methyl (actellic dust) has been utilized in the storage of dried products against insect infestation, thereby increasing their shelf life. This study investigated the effect of pirimiphos methyl on the proximate and mineral composition of Synodontis nigrita and Tilapia mariae in Jamieson River which were purchased from the fish landing site in Sapele Delta State, Nigeria. The fish samples were divided into three batches of fresh samples (batch I), oven - dried samples (batch II) and actellic dust treated samples (batch III). The proximate composition (moisture, protein, fat, ash, crude fibre, and carbohydrate) and mineral content (sodium, potassium, calcium, and magnesium) of the samples were determined using the AOAC standard methods. Results showed that actellic dust treatment greatly increased the protein (19.35 to 23.31%), fat (8.12% to 22.31%), and raw fibre content (0.69 to 8.03%) in S. nigrita and protein (7.09 to 25.46%), fat (5.13 to 11.70%), and raw fibre content (3.40 to 14.23%) in T. mariae. The mineral elements analyzed showed no well-defined order across the treatment levels with potassium being the most abundant mineral element in all fish samples. Actellic dust has been shown to improve the proximate composition and shelf life of both fish species studied, and its use as a fish preservative is therefore recommended. [ABSTRACT FROM AUTHOR]

Objective: There is an urgent need to test and incorporate new molecules with promising efficacy and novel mode of action to control insecticide-resistant mosquito vectors for disease control. We tested a new compound, clothianidin (SumiShield 50 WG), for its efficacy as an indoor residual spray (IRS) for the control of pyrethroid-resistant Anopheles culicifacies (Diptera: Culicidae) in comparison with pirimiphos methyl (Actellic CS) as a positive control.Methods: Ten villages were selected, five each for IRS with clothianidin (300 mg AI/m2 ) and pirimiphos methyl (1000 mg AI/m2 ) in Almatti Dam catchment area in Karnataka state, India. Entomological parameters were monitored in these sprayed villages using standard methods. Assessment of quality of spray was performed by analysing the insecticide content in the filter paper samples collected from sprayed houses. Perceptions of spray men and inhabitants were recorded post-spray on safety of these molecules.Results: The mean applied to target ratio of content was 1.7 (n = 29) for clothianidin and 1.8 (n = 50) for pirimiphos methyl on filter paper samples analysed. Residual activity (≥80% mortality in exposed mosquitoes) after 24 h post-exposure of SumiShield WG was 5 months and increased to 6 months when the holding period was extended to 120 h and that of Actellic CS was 3 months at 24-h holding period and extended to 4 months at 120-h extended holding period. The mean densities of An. culicifacies in both arms fell drastically post-spray. In light trap collections, density of mosquitoes collected indoors was lower than outdoors in both arms indicating effectiveness of IRS. SumiShield WG was more efficacious in reducing the per-structure density than Actellic CS. The proportion of nulliparous mosquitoes was higher than that of parous mosquitoes during post-spray collections in both arms. The majority of adverse events reported were transitory and subsided without medication.Conclusion: Indoor residual spraying with SumiShield WG was found effective, operationally feasible and safe, and it is effective for up to 6 months. [ABSTRACT FROM AUTHOR]

Abstract Background The National Malaria Control Program (NMCP) has been using pirimiphos methyl for the first time for indoor residual spraying (IRS) in Benin. The first round was a success with a significant decrease of entomological indicators of malaria transmission in the treated districts. We present the results of the entomological impact on malaria transmission. Entomologic parameters in the control area were compared with those in intervention sites. Methods Mosquito collections were carried out in three districts in the Atacora-Dongo region of which two were treated with pirimiphos methyl (Actellic 50EC) (Tanguiéta and Kouandé) and the untreated (Copargo) served as control. Anopheles gambiae s.l. populations were sampled monthly by human landing catch. In addition, window exit traps and pyrethrum spray catches were performed to assess exophagic behavior of Anopheles vectors. In the three districts, mosquito collections were organized to follow the impact of pirimiphos methyl IRS on malaria transmission and possible changes in the behavior of mosquitoes. The residual activity of pirimiphos methyl in the treated walls was also assessed using WHO bioassay test. Results A significant reduction (94.25%) in human biting rate was recorded in treated districts where an inhabitant received less than 1 bite of An. gambiae per night. During this same time, the entomological inoculation rate (EIR) dramatically declined in the treated area (99.24% reduction). We also noted a significant reduction in longevity of the vectors and an increase in exophily induced by pirimiphos methyl on An. gambiae. However, no significant impact was found on the blood feeding rate. Otherwise, the low residual activity of Actellic 50 EC, which is three months, is a disadvantage. Conclusion Pirimiphos methyl was found to be effective for IRS in Benin. However, because of the low persistence of Actellic 50EC used in this study on the treated walls, the recourse to another more residual formulation of pirimiphos methyl is required.

Degradation of pirimiphos methyl (1) as an active ingredient in Minawet insecticide 250 EC formulation in aqueous solution was studied. The absorbance, pH, COD (Chemical Oxygen Demand) in aerated solution, and the analyses of degradation products at various irradiation doses with dose rate of 5 kGy/h were observed. The absorbance decreased rapidly at low doses (£ 10 kGy), while at high doses (> 10 kGy) decreased slowly. The optimum irradiation dose for pirimiphos methyl degradation in aerated solution was found to be 15 kGy at pH 3.6. At that condition, more than 99% of pirimiphos methyl has been degraded and the COD of solution decreased about 82%. The analysis of irradiated samples by GC-MS and HPLC showed that 2-diethylamino-6-methyl-4-oxo-3,4-dihydropyrimidine (3) and oxalic acid were clarified as degraded products

Background: Alternative long-lasting, practical and effective tools for applying insecticides on home walls against malaria vectors need to be developed. The use of wall hangings made from netting on interior walls for aesthetic purposes is a common practice in rural communities. Insecticide-treated net wall hangings can be produced in a long-lasting format and used in an approach that simulates indoor residual spraying (IRS). Methods: The efficacy of net wall hangings (NWH) treated with the residual organophosphate insecticide, pirimiphos methyl (1 g/sq m), was evaluated in experimental huts against malaria vectors in Muheza, Tanzania. To determine the optimum level of wall coverage required, NWH were tested on ceiling only, two walls, four walls, or four walls plus ceiling. Comparison was made with deltamethrin-treated NWH on two walls. Results: Pirimiphos methyl (p-methyl)-treated NWH (on two walls) killed significantly higher proportions of anophelines (92% of Anopheles gambiae and 79% of Anopheles funestus) than the deltamethrin-treated NWH (15% of An. gambiae and 17% of An. funestus) (P < 0.001). WHO susceptibility tests showed that the local vector population was susceptible to the organophosphates but resistant to pyrethroids. Mortality rates were significantly higher in huts with p-methyl NWH on two walls (92% for An. gambiae and 79% for An. funestus) than on ceiling only (61% for An. gambiae and 62% for An. funestus, P < 0.05). There was no improvement in mortality when wall coverage with p-methyl NWH increased beyond two walls. Blood-feeding rates with p-methyl NWH were generally high across all the treatments (52-77%) and did not differ significantly from the control (64-67%). There was no evidence of reduced blood-feeding or increased exiting with increase in wall coverage with p-methyl NWH. Conclusions: Net wall hangings are an effective means of delivering insecticides in the domestic environment against malaria vectors. They could be more practical and acceptable than IRS thus showing enormous potential for malaria vector control. Appropriate binding or incorporation technology needs to be developed to enable the production of p-methyl NWH with residual activity lasting over a number of years. [ABSTRACT FROM AUTHOR]

Background The National Malaria Control Program (NMCP) has been using pirimiphos methyl for the first time for indoor residual spraying (IRS) in Benin. The first round was a success with a significant decrease of entomological indicators of malaria transmission in the treated districts. We present the results of the entomological impact on malaria transmission. Entomologic parameters in the control area were compared with those in intervention sites. Methods Mosquito collections were carried out in three districts in the Atacora-Dongo region of which two were treated with pirimiphos methyl (Actellic 50EC) (Tanguiéta and Kouandé) and the untreated (Copargo) served as control. Anopheles gambiae s.l. populations were sampled monthly by human landing catch. In addition, window exit traps and pyrethrum spray catches were performed to assess exophagic behavior of Anopheles vectors. In the three districts, mosquito collections were organized to follow the impact of pirimiphos methyl IRS on malaria transmission and possible changes in the behavior of mosquitoes. The residual activity of pirimiphos methyl in the treated walls was also assessed using WHO bioassay test. Results A significant reduction (94.25%) in human biting rate was recorded in treated districts where an inhabitant received less than 1 bite of An. gambiae per night. During this same time, the entomological inoculation rate (EIR) dramatically declined in the treated area (99.24% reduction). We also noted a significant reduction in longevity of the vectors and an increase in exophily induced by pirimiphos methyl on An. gambiae. However, no significant impact was found on the blood feeding rate. Otherwise, the low residual activity of Actellic 50 EC, which is three months, is a disadvantage. Conclusion Pirimiphos methyl was found to be effective for IRS in Benin. However, because of the low persistence of Actellic 50EC used in this study on the treated walls, the recourse to another more residual formulation of pirimiphos methyl is required. [ABSTRACT FROM AUTHOR]

Five field and greenhouse populations of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), were collected from five different districts across the island of Cyprus, both in field and greenhouse crops, and tested to determine levels of resistance. Standard leaf-disk spray application bioassay procedures were used to determine the LC50s for five chemicals: abamectin, acrinathrin, fenazaquin, pirimiphos methyl, and bifenazate. Selection of these compounds was based on the widespread use by farmers as well as on the frequent control failures against T urticae reported in the past. Resistance of T. urlicae was detected to abamectin, acrinathrin, fenazaquin, and pirimiphos methyl. The resistance ratios were calculated relative to the German susceptible reference strain. The highest resistance ratios at LC50 value were recorded for abamectin in a greenhouse rose population (RR = 3822), followed by a field bean (RR = 1356) and field tomato population (RR = 1320). Significantly high resistance levels were also found for acrinathrin where the highest resistance ratios at LC50 were recorded in a field bean T. urticae population (RR = 903). For fenazaquin, the highest resistance levels were recorded in a field tomato population (RR = 310). Lower resistance levels were found for pirimiphos methyl (13.3 < RR < 77.4) in all populations. Low susceptibility of T. urticae was observed for bifenazate (2.7 < RR < 24.4) in all populations. These results suggest that at least the use of abamectin and acrinathrin should be avoided or minimized for the control of T. urticae populations in indoor and outdoor environments. [ABSTRACT FROM AUTHOR]

The article discusses the study regarding the status of insecticide resistance in Q biotype Bemisia tabaci populations in Crete, Greece. A major problem in the area is the control of Bemisia with chemical insecticides owing to the rapid development of resistance. Application history records showed extensive use of neonicotinoids, organophosphates, and carbamates. High resistance levels were identified in the majority of populations for imidacloprid and cypermethrin. A strong correlation between resistance to imidacloprid and the number of applications with neonicotinoids was observed.

Abstract: For investigating the carryover of some organophosphorus pesticide residues in the cereal food chain from grain to consumer, a study was set up on durum wheat, semolina and pasta. Pesticide-free durum wheat was placed into a small-scale model of a commercial storage vessel and treated with pesticides (malathion, fenitrothion, chlorpyrifos methyl, and pirimiphos methyl) according to the raw material legislation of Turkey. The residue levels of insecticides were determined in wheat, semolina, and spaghetti produced from stored wheat at various time intervals during five months of storage. A multiresidue analysis was performed using GC equipped with an NPD. The confirmation was performed by GC–MS. The residue levels of insecticides in wheat exceeded the maximum residue limits (MRLs) for wheat. The storage period was generally not effective enough to reduce the residues in wheat to levels below the MRLs. Although a considerable amount of the insecticides remained in the semolina, spaghetti processing significantly reduced residue concentrations in general. Pirimiphos methyl was the most persistent of the insecticides and comparatively less substantial loss occurred during milling and spaghetti processing due to its physicochemical properties. [Copyright &y& Elsevier]

Three plant products with known insecticidal properties, a dry extract of flowers of Chrysanthemum cinerariaefolium (Trevir.) Vis. produced in Rwanda, an ethanol extract of seeds of neem, Azadirachta indica A. Juss, and crushed leaves of Tetradenia riparia Hochst Codd, a traditional Rwandan medicine, were mixed with beans, Phaseolus vulgaris L., for storage protection. These plant-protected beans were compared with "off the shelf' beans that were being sold to consumers by the Rwandan National Agricultural Products Marketing Organization (OPROVIA). A trained sensory panel determined that beans treated with neem and C. cinerariaefolium were as acceptable after 8 months storage as those being sold throughout Rwanda by the marketing organization. Beans marketed by this organization were all treated with the standard insecticide application in Rwanda, 0.01% weight/weight pirimiphos methyl in a powder formulation. Instrumental hardness (% hard-to-cook/mean gram force) after 20 months of storage was acceptable for beans stored with neem or with C. cinerariaefolium or with the conventional government application of pirimiphos methyl. Use of either neem or C. cinerariaefolium for storage protection should not affect consumer acceptance of dry beans. [ABSTRACT FROM AUTHOR]

Objective: There is an urgent need to test and incorporate new molecules with promising efficacy and novel mode of action to control insecticide-resistant mosquito vectors for disease control. We tested a new compound, clothianidin (SumiShield 50 WG), for its efficacy as an indoor residual spray (IRS) for the control of pyrethroid-resistant Anopheles culicifacies (Diptera: Culicidae) in comparison with pirimiphos methyl (Actellic CS) as a positive control., Methods: Ten villages were selected, five each for IRS with clothianidin (300 mg AI/m 2 ) and pirimiphos methyl (1000 mg AI/m 2 ) in Almatti Dam catchment area in Karnataka state, India. Entomological parameters were monitored in these sprayed villages using standard methods. Assessment of quality of spray was performed by analysing the insecticide content in the filter paper samples collected from sprayed houses. Perceptions of spray men and inhabitants were recorded post-spray on safety of these molecules., Results: The mean applied to target ratio of content was 1.7 (n = 29) for clothianidin and 1.8 (n = 50) for pirimiphos methyl on filter paper samples analysed. Residual activity (≥80% mortality in exposed mosquitoes) after 24 h post-exposure of SumiShield WG was 5 months and increased to 6 months when the holding period was extended to 120 h and that of Actellic CS was 3 months at 24-h holding period and extended to 4 months at 120-h extended holding period. The mean densities of An. culicifacies in both arms fell drastically post-spray. In light trap collections, density of mosquitoes collected indoors was lower than outdoors in both arms indicating effectiveness of IRS. SumiShield WG was more efficacious in reducing the per-structure density than Actellic CS. The proportion of nulliparous mosquitoes was higher than that of parous mosquitoes during post-spray collections in both arms. The majority of adverse events reported were transitory and subsided without medication., Conclusion: Indoor residual spraying with SumiShield WG was found effective, operationally feasible and safe, and it is effective for up to 6 months., (© 2018 John Wiley & Sons Ltd.)

We measured the concentrations of organophosphorus pesticide （chlorpyrifos-methyl, pirimiphos-methyl and fenitrothion） residues in domestic and imported commercial wheat products （flour, noodles, cookies） collected from 2008 to 2016. Chlorpyrifos-methyl and fenitrothion in domestic flour samples were detected in 16 out of 34 samples at levels of ＜0.001 to 0.016 ppm, and in 14 out of 34 samples at levels of ＜0.001 to 0.004 ppm. Chlorpyrifos-methyl was detected in 22 out of 38 domestic cookies at levels of ＜0.001 to 0.054 ppm （median: 0.001 ppm）. Relatively high concentrations of chlorpyrifos-methyl （0.005 to 0.054 ppm） were found in six domestic cookies containing wheat bran. Pirimiphos-methyl was detected in 32 out of 68 cookies from foreign countries at levels of ＜0.001 to 0.11 ppm. Pirimiphos-methyl was detected frequently in products imported from Europe.

Insecticides must be tested to determine their nontarget toxicity when released into the environment. Currently, new insecticides registered in Europe are likely to be tested, at the highest tier, in microcosms or mesocosms, although the cost-effectiveness of these systems has yet to be established. This study investigated the effects of the organophosphorus insecticide pirimiphos methyl on the amphipod Gammarus pulex L. in 250-ml laboratory beakers and 50,000-L pond mesocosms.Acetylcholinesterase activity and survival were used as indicators of the insecticide's bioavailability and toxicity. The results from beakers and mesocosms were indistinguishable, indicating that the former are efficient tools for predicting the bioavailability of chemicalssuch as pirimiphos methyl that have high toxicity but low persistence in the environment. [ABSTRACT FROM AUTHOR]