Differences in Bifenthrin and Fipronil Susceptibility Among Invasive Latrodectus spp. (Araneae: Theridiidae) and Nontarget Spiders in Japan

2021 ◽  
Author(s):  
Daisuke Hayasaka ◽  
Tomoki Numa ◽  
Takuo Sawahata
Keyword(s):  
Ecological Impacts ◽  
Toxicity Tests ◽  
Effective Population ◽  
Pyrethroid Insecticides ◽  
Parasteatoda Tepidariorum ◽  
Residual Toxicity ◽  
Insecticide Concentration ◽  
Nontarget Species ◽  
Spider Communities ◽  
Ecological Importance

Abstract Prompt responses to invasive Latrodectus spiders introduced unintentionally are needed worldwide due to their medical and ecological importance. Latrodectus species are chemically controlled using pyrethroid insecticides despite concerns about the ecological impacts of these compounds on biodiversity/ecosystems. Here, the relative sensitivities (acute toxicity: 48-h LC50) of Latrodectus hasseltii Thorell and Latrodectus geometricus C.L. Koch from Japan to the conventional neurotoxic insecticide bifenthrin (pyrethroid) and a new candidate insecticide, fipronil (phenylpyrazole), were examined. Acute residual toxicity tests of these compounds in two nontarget spiders (Parasteatoda tepidariorum C.L. Koch (Araneae: Theridiidae), Badumna insignis L. Koch (Araneae: Desidae)) were conducted for comparison. To test whether bifenthrin and fipronil toxicities differed among the four spiders, corresponding species sensitivity distributions (SSDs) were compared, and hazardous concentrations were determined. Sensitivity (especially in the nontarget species) was two to four orders of magnitude higher for bifenthrin than for fipronil. The SSD patterns of the two insecticides differed significantly, with the spider communities being more sensitive to bifenthrin than to fipronil. The lethal bifenthrin concentration for Latrodectus may reduce spider populations by over 70–90%. If L. hasseltii (established throughout Japan) is targeted for effective population suppression rather than L. geometricus (with a limited distribution range) using the specified insecticide concentration (LC50 value) for fipronil, less than 20% of spider communities will be impacted. Chemical operations aimed at the effective population management and subsequent eradication of invasive Latrodectus spiders while supporting local biodiversity conservation would benefit from considerations of fipronil dosages and target species sensitivities.

scholarly journals A simple mooring modification reduces impacts on seagrass meadows

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Anna L. Luff ◽  
Emma V. Sheehan ◽  
Mark Parry ◽  
Nicholas D. Higgs
Keyword(s):  
Species Richness ◽  
Seagrass Meadow ◽  
Habitat Degradation ◽  
Ecological Impacts ◽  
Sediment Composition ◽  
Simple Modification ◽  
Seagrass Meadows ◽  
Ecological Importance ◽  
Detrimental Impact ◽  
Seagrass Density

AbstractMoorings can have a detrimental impact on seagrass, fragmenting the meadows, resulting in the habitat degradation. To reduce contact of the moorings with the seabed we attached small floats along the chain of a traditional swing mooring and monitored the ecological impacts of this modified mooring, with reference to a standard swing mooring, in a seagrass meadow under high tidal influence. After three years, seagrass density surrounding the modified mooring was over twice as high as that of the standard mooring, with blade length surrounding the modified mooring also found to exceed that of the standard mooring. Seagrass-associated epifaunal species richness was twice as high surrounding the modified mooring compared to the standard mooring. Sediment composition was considerably finer at the modified mooring, indicative of increased disturbance surrounding the standard mooring. A simple modification to existing swing moorings can mitigate some of the impacts of moorings on seagrass meadows, whilst accommodating for tidal fluctuations. The scale of the differences observed between the mooring types demonstrates the susceptibility of seagrass meadows to damage from swing moorings. Given the ecological importance of these habitats, it is crucial that action is taken to reduce further degradation, such as that demonstrated here.

scholarly journals Zebrafish Embryo Toxicity of a Binary Mixture of Pyrethroid Insecticides: d-Tetramethrin and Cyphenothrin

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Janthri C. Mendis ◽  
Thejani K. Tennakoon ◽  
Chanika D. Jayasinghe
Keyword(s):  
Binary Mixture ◽  
Zebrafish Embryo ◽  
Lethal Effect ◽  
Probit Analysis ◽  
Toxicity Tests ◽  
Time Interval ◽  
Synthetic Pyrethroids ◽  
Zebrafish Embryos ◽  
Pyrethroid Insecticides ◽  
Embryo Toxicity

Pesguard FG161™, a mixture of d-tetramethrin and cyphenothrin (1:3 ratio), is extensively used to achieve rapid control of adult dengue vector, Aedes aegypti, during the disease outbreaks. Both d-tetramethrin and cyphenothrin are synthetic pyrethroids that are known to have adverse effects on non-mammalian organisms such as fish. The present study intended to use zebrafish embryo toxicity model to investigate the toxic effect of the above binary mixture on fish. Particularly, zebrafish embryo toxicity model provides an alternative to acute fish toxicity tests in terms of animal welfare perspective as the embryos are not considered live until 5 days after fertilization. The zebrafish embryos (2 hrs after fertilization) were exposed to a binary mixture of pyrethroids at different concentrations (d-tetramethrin: 0.01 – 1.20 μmolL-1 and cyphenothrin: 0.03 – 3.20 μmolL-1) for 24, 48, and 72 hrs at room temperature (26°C) according to the OECD guideline no. 236. Percentage mortality of embryos were calculated by observing the lethal endpoints and LC50 values were calculated for each time interval employing the probit analysis. This binary mixture was highly toxic to zebrafish embryos and was found to be concentration and time dependent. LC50 values at 24 hrs (d-tet: 0.58 μmolL-1, cyp: 1.74 μmolL-1) were significantly reduced in 48 hrs (d-tet: 0.11 μmolL-1, cyp: 0.33 μmolL-1) and 72 hrs (d-tet: 0.03 μmolL-1, cyp: 0.09 μmolL-1). Coagulation of embryos was the most common lethal effect observed and lack of somite formation and lack of heartbeat were also observed. The present study revealed that the binary mixture is highly toxic to zebrafish embryos even when based on nominal concentrations. Hence, extensive use of these pesticides could be detrimental to fish population and integrated vector control methods which involve the minimum use of insecticides are recommended. Further, this study highlights the applicability of zebrafish embryo toxicity model as an alternative method to investigate the toxicity of pyrethroids to fish.

scholarly journals The use of respirometry for the evalutation of an industial wastewater toxicity over activated sludge

2007 ◽  
pp. 439-447
Author(s):  
Fabio Kaczala ◽  
Marcia Marques ◽  
William Hogland
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Complex Mixture ◽  
Metabolic Inhibition ◽  
Ecological Impacts ◽  
Toxic Effects ◽  
Toxicity Tests ◽  
Formaldehyde Concentration ◽  
Industrial Wastewaters

The discharge of industrial wastewaters with toxic substances in wastewater treatment plants may cause relevant inhibition of microbiological metabolism. A number of toxicity tests available mostly focus on ecological impacts on water recipients by using macro invertebrates as bio-indicators. However, toxic effects occurring in wastewater treatment plants cannot be properly addressed with this approach. A promising method that has been used to investigate microbiological inhibition caused by industrial wastewaters is,.the respirometric test. As part of a treatability study, the present investigation aimed to assess the toxic effects of an industrial wastewater generated in a wood-floor industry, located in Nybro, Sweden over activated sludge microorganisms. The wastewater results from washing/cleaning of machineries that continuously apply urea-formaldehyde resins on wood particle boards. The respirometric method was able in a short time to assess both the inhibition and the stimulation of microbial metabolism caused by this particular tested effluent. Metabolic inhibition was positively correlated with dilution factors and formaldehyde concentrations within the aqueous phase. Whereas 1,989.4 mg L"1 of formaldehyde caused 50% of metabolic inhibition, concentrations below 156 mg L"1 did stimulate it. High EC50 values suggest that in thepresence of other compounds, antagonistic processes are taking place, reducing toxic effects of formaldehyde. Finally it was concluded that toxicity tests carried out with single substances in synthetic waters have limited value if the ultimate goal is to develop real wastewater treatment systems. It is important to highlight that formaldehyde was here used as an indicator and the correlation between inhibition of respiration and formaldehyde concentration is actually reflecting the effect of not only this particular substance but the complex mixture of substances presented in the glue wastewater.

scholarly journals Biodegradation of a mixture of benzophenone, benzophenone-3, caffeine and carbamazepine in a laboratory test filter

2017 ◽  
Vol 82 (12) ◽  
pp. 1445-1459 ◽  
Author(s):  
Minja Bogunovic ◽  
Varja Knezevic ◽  
Jelica Simeunovic ◽  
Ivana Teodorovic ◽  
Ivana Ivancev-Tumbas
Keyword(s):  
Laboratory Test ◽  
Substantial Reduction ◽  
Mixture Toxicity ◽  
Initial Mixture ◽  
Transformation Products ◽  
Toxicity Tests ◽  
Inert Material ◽  
Residual Toxicity ◽  
Test Filter ◽  
Adsorption Processes

The biodegradation of a mixture of four pharmaceutical and personal care products (PPCPs) (benzophenone (BP), benzophenone-3 (BP-3), caffeine (CF) and carbamazepine (CBZ)) was studied in a laboratory test filter. The column was filled with inert material to exclude the adsorption processes and to enable the development of the biofilm, while river water was recirculated. High removal for BP, BP-3 and CF was observed from the beginning of the experiment at the initial concentration of 20 ?g L-1 (90?99 %). In the case of CBZ analytical difficulties were experienced. The efficacy of biodegradation reflected as a change of the overall toxicity of initial mixture of selected PPCPs vs. toxicity of samples which were undergone different biodegradation phases was assessed with two standard laboratory tests with apical endpoint ? acute toxicity test with Daphnia magna (immobilisation) and bioluminescence inhibition with Vibrio fisheri. Toxicity tests showed the substantial reduction of the overall mixture toxicity in a laboratory test filter. The residual toxicity to D. magna might be attributed to undetected transformation products.

scholarly journals Synergistic effects of binary mixtures of linalool with pyrethroids against fall armyworm

2020 ◽  
Vol 36 ◽  
Author(s):  
Sérgio Macedo Silva ◽  
João Paulo Arantes Rodrigues da Cunha ◽  
César Henrique Souza Zandonadi ◽  
Heli Heros Teodoro de Assunção ◽  
Matheus Gregorio Marques
Keyword(s):  
Essential Oil ◽  
Binary Mixtures ◽  
Spodoptera Frugiperda ◽  
Synergistic Effects ◽  
Larval Mortality ◽  
Lethal Dose ◽  
Fall Armyworm ◽  
Toxicity Tests ◽  
Pyrethroid Insecticides ◽  
Corn Plants

The present work aimed to determine the toxicity of linalool and evaluate the lethal and toxic effects of linalool associated with pyrethroids in binary mixtures to fall armyworm (Spodoptera frugiperda). The insects used in the experiment were obtained from stock breeding initiated from larvae collected from conventional corn plants, grown in an experimental area, in the city of Uberlândia, Minas Gerais. Also, it was obtained essential oil from a variety of Ocimum basilicum, with a high content of linalool (80%), found naturally, as a measure of comparison of different linalool (97.5%) assays. Dose-response bioassays with 3rd instar larvae were performed to determine lethal dose for 50% mortality (LD50) of linalool. Toxicity tests were also performed with O. basilicum essential oil and with pyrethroid insecticides: deltamethrin and its commercial product (Decis 25 EC, Bayer®). After this, combinations between different doses of these products were made and applied on 3rd instar larvae of Spodoptera frugiperda (Smith). Linalool presented high toxicity to S. frugiperda (LD50 = 0.177 μL a.i. μL-1). It was observed neurotoxic effects after the linalool application since the insects presented an aspect of confusion, followed by extreme agitation and finally death. All binary mixtures caused mortality higher than the products applied alone (deltamethrin and linalool) used at 100% LD50, except to 75% LD50 deltamethrin added to 25% LD50 linalool, whose mortality did not differ the products alone, in 24 hours. It was obtained over 90% larval mortality when linalool was combined with 25% LD50 of deltamethrin, in 24 and 48 hours after application, and over 80% of mortality when linalool was combined with 25% LD50 of Decis, only in 48 hours after application. We conclude that linalool is a potential insecticidal and can be associated with pyrethroids to control of S. frugiperda. Further studies are required in order to evaluate the synergistic combinations against field populations of S. frugiperda.

Energy and nutrient fluxes from rivers and streams into terrestrial food webs

2006 ◽  
Vol 57 (1) ◽  
pp. 15 ◽  
Author(s):  
Andrea Ballinger ◽  
P. S. Lake
Keyword(s):  
Food Webs ◽  
River Regulation ◽  
Ecological Impacts ◽  
Allochthonous Inputs ◽  
Productivity Gradients ◽  
Research Questions ◽  
Ecological Importance ◽  
Landscape Scales ◽  
Riverine Systems ◽  
Exchange Surface

Ecologists long have been aware that there is flux of energy and nutrients from riverine systems to the surrounding terrestrial landscape and vice versa. Riparian ecotones are diverse and ecologically important. Consequently, there is substantial literature examining faunal-mediated transfers of energy and nutrients from rivers into terrestrial food webs. A wide variety of taxa has been shown to utilise riparian resources, from species specialised for existence at the aquatic–terrestrial interface to opportunistic predators and scavengers. Outputs from rivers may be influenced by productivity gradients, channel geometry and the condition of the exchange surface. Until recently, consideration of faunal-transferred, allochthonous inputs has been peripheral to other research questions. The development of general models of inter-habitat transfers, together with advances in technology, has placed questions about the ecological importance of riverine outputs squarely on the research agenda. Researchers now are investigating how aquatic subsidies influence food-web dynamics at landscape scales. However, ecologists continue to largely ignore subsidisation of terrestrial food webs by energy and nutrients from floodwaters in lowland river–floodplain systems. The dearth of information about the benefits of flooding to terrestrial consumers appears to have resulted in underestimation of the gross ecological impacts of river regulation.

LABORATORY STUDIES ON THE PERSISTENCE AND BEHAVIOUR IN SOIL OF FOUR PYRETHROID INSECTICIDES

1981 ◽  
Vol 113 (8) ◽  
pp. 685-694 ◽  
Author(s):  
C. R. Harris ◽  
R. A. Chapman ◽  
Carol Harris
Keyword(s):  
Soil Type ◽  
Negative Temperature Coefficient ◽  
Negative Temperature ◽  
Toxicity Tests ◽  
Contact Toxicity ◽  
Laboratory Studies ◽  
Pyrethroid Insecticides ◽  
Muck Soil ◽  
Soil Insecticides ◽  
Test Insect

AbstractIn direct contact toxicity tests with four pyrethroid and three standard insecticides, using 24–48 h old crickets, Acheta pennsylvanicus (Burmeister), as test insects, carbofuran was most toxic > cypermethrin > fensulfothion > chlorpyrifos > fenvalerate > fenpropanate > permethrin. In moist (5% water) Plainfield sand, using the same test insect, chlorpyrifos was most toxic > carbofuran > fenpropanate > cypermethrin > permethrin > fenvalerate > fensulfothion, i.e. the pyrethroids, although quite strongly adsorbed by soil, were still moderately active as soil insecticides. All pyrethroids were less toxic in muck soil as compared with Plainfield sand, and in air-dry (0.5% water) as compared with moist (5% water) Plainfield sand, with the effects being less on cypermethrin and fenvalerate and greater on permethrin and fenpropanate. None of the pyrethroids was affected by soil type and moisture to the same extent as was carbofuran. Permethrin, fenvalerate, and cypermethrin showed a negative temperature coefficient of toxicity in moist Plainfield sand, being from 1.4 to 1.9× more toxic at 15° than at 32°C. Fenpropanate, like carbofuran, was slightly more toxic at 32° than at 15°C. Generally, soil type, moisture, and temperature had minimal effects on the toxicity of the four pyrethroid insecticides. In persistence studies over 48 weeks, using Plainfield sand, the pyrethroids were more persistent than chlorpyrifos, but less persistent than dieldrin. Under these laboratory conditions, permethrin and fenvalerate were slightly more persistent, while fenpropanate and cypermethrin were as persistent as carbofuran. Trans-isomers of permethrin and cypermethrin declined more quickly in the sand than did the cis-isomers and of the trans-isomers the 1S,trans declined much faster than the 1R,trans while little difference was observed for the corresponding 1S- and 1R,cis-isomers.

Non-Oxidative Destruction of TNT, RDX, and HMX on Contaminated Soil Using Subcritical (Hot/Liquid) Water

2003 ◽  
Author(s):  
Steven B. Hawthorne ◽  
Arnaud J. M. Lagadec ◽  
David J. Miller ◽  
Peter J. Hammond
Keyword(s):  
Liquid Water ◽  
Vibrio Fischeri ◽  
Degradation Products ◽  
Pilot Scale ◽  
Toxicity Tests ◽  
Residual Toxicity ◽  
Initial Cost ◽  
Scale Unit ◽  
Acute Toxicity Tests ◽  
Derivatives Of

Subcritical (hot/liquid) water was used in a simple static (non-flowing) vessel to treat three soils from former defense sites which were contaminated with the explosives TNT (12 wt.%), or RDX (0.62 wt.%) and HMX (0.16 wt. %). Significant degradation of RDX began at 100 C, and at 125 C for TNT and HMX, with the bulk of the undergraded explosives remaining in the soil rather than in the water phase. Based on HPLC/UV analysis, intermediate degradation products formed, but quickly degraded at < 250 C. Remediations performed using a generator-powered mobile pilot-scale unit (4 to 6 kg soil) with 4-L of water at 275 C for 1 h of real soils resulted in > 99.9% destrcution of TNT and HMX, and > 99.5% desstruction of RDX. None of the mutagenic nitroso derivatives of RDX and HMX were formed. “Microtox” acute toxicity tests with Vibrio fischeri showed no significant (compared to background) residual toxicity in either the process wastewaters or leachates from the treated soils. The operation is closed-loop (no air or water emissions), and process water can be recycled without treatment. Initial cost analysis indicates that the process should be competitive with other approaches such as bioremediation.

scholarly journals Retrospective evaluation of the effectiveness of indoor residual spray with pirimiphos‐methyl (Actellic) on malaria transmission in Zambia

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Joseph Keating ◽  
Joshua O. Yukich ◽  
John M. Miller ◽  
Sara Scates ◽  
Busiku Hamainza ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Health Facility ◽  
Malaria Case ◽  
Malaria Incidence ◽  
Population Level ◽  
World Health ◽  
Effective Population ◽  
Cross Sectional ◽  
Pyrethroid Insecticides ◽  
Catchment Areas

Abstract Background Widespread insecticide resistance to pyrethroids could thwart progress towards elimination. Recently, the World Health Organization has encouraged the use of non-pyrethroid insecticides to reduce the spread of insecticide resistance. An electronic tool for implementing and tracking coverage of IRS campaigns has recently been tested (mSpray), using satellite imagery to improve the accuracy and efficiency of the enumeration process. The purpose of this paper is to retrospectively analyse cross-sectional observational data to provide evidence of the epidemiological effectiveness of having introduced Actellic 300CS and the mSpray platform into IRS programmes across Zambia. Methods Health facility catchment areas in 40 high burden districts in 5 selected provinces were initially targeted for spraying. The mSpray platform was used in 7 districts in Luapula Province. An observational study design was used to assess the relationship between IRS exposure and confirmed malaria case incidence. A random effects Poisson model was used to quantify the effect of IRS (with and without use of the mSpray platform) on confirmed malaria case incidence over the period 2013–2017; analysis was restricted to the 4 provinces where IRS was conducted in each year 2014–2016. Results IRS was conducted in 283 health facility catchment areas from 2014 to 2016; 198 health facilities from the same provinces, that received no IRS during this period, served as a comparison. IRS appears to be associated with reduced confirmed malaria incidence; the incidence rate ratio (IRR) was lower in areas with IRS but without mSpray, compared to areas with no IRS (IRR = 0.91, 95% CI 0.84–0.98). Receiving IRS with mSpray significantly lowered confirmed case incidence (IRR = 0.75, 95% CI 0.66–0.86) compared to no IRS. IRS with mSpray resulted in lower incidence compared to IRS without mSpray (IRR = 0.83, 95% CI 0.72–0.95). Conclusions IRS using Actellic-CS appears to substantially reduce malaria incidence in Zambia. The use of the mSpray tool appears to improve the effectiveness of the IRS programme, possibly through improved population level coverage. The results of this study lend credence to the anecdotal evidence of the effectiveness of 3GIRS using Actellic, and the importance of exploring new platforms for improving effective population coverage of areas targeted for spraying.

scholarly journals Evaluation of the Effect of Fungatol and Gamma-T-ol on the Emergence and Adult Parasitoid Survival of Mummies of Cotton Aphids Parasitized by Aphidius colemani

Insects ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 38
Author(s):  
Errol Hassan ◽  
Md Munir Mostafiz ◽  
Ellen Talairamo Iramu ◽  
Doug George ◽  
Kyeong-Yeoll Lee
Keyword(s):  
Production Systems ◽  
Aphis Gossypii ◽  
Adult Emergence ◽  
Toxicity Tests ◽  
Adult Longevity ◽  
Cotton Aphid ◽  
Safe Alternative ◽  
Aphidius Colemani ◽  
Botanical Pesticide ◽  
Residual Toxicity

Beneficial insects play a major role in controlling pest populations. In sustainable agricultural production systems, control methods compatible with integrated pest management (IPM) are preferred over broad-spectrum pesticides. EOs from aromatic plants may provide a new and safe alternative to synthetic chemicals. In this research, the efficacy of Fungatol, Gamma-T-ol, Fungatol plus neem, and Gamma-T-ol plus neem was evaluated against Aphidius colemani Viereck (Hymenoptera: Braconidae; Aphidiidae), the parasitoid of the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae). Under laboratory and greenhouse conditions, five different concentrations of each formulation were applied to parasitized mummies and adult parasitoids. Results for parasitoid emergence from aphid mummies sprayed with different concentrations of Fungatol, Gamma-T-ol, Fungatol plus neem, and Gamma-T-ol plus neem in the laboratory and glasshouse showed that the formulations did not adversely affect adult emergence as rates above 60% were observed. For residual toxicity tests done by exposing adult parasitoids to a fresh, dry biopesticide film sprayed on glass plates, less than 20% mortality was observed after 48 h of exposure. Adult longevity tests revealed that the highest concentrations of some of the formulations evaluated were slightly toxic to A. colemani. According to the IOBC rating, our results indicated that most of the tested concentrations for each formulation were harmless to A. colemani. Based on the above results, it may be proposed that the formulations evaluated in this study are potential botanical pesticide candidates for incorporation into an IPM program.

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