Concentration Of Alpha-cypermethrin Research Articles

Proteomics Reveals Damaging Effect of Alpha-Cypermethrin Exposure in a Non-Target Freshwater Microalga Chlorella sp. NC-MKM

Alpha-cypermethrin, a pyrethroid pesticide, is frequently used on crops to prevent insect attacks. However, occasionally, due to drift, leaching, or with rainwater, it enters the aquatic environment and poses a serious threat to the growth of non-target aquatic organisms. In the current study, we were interested in investigating the damaging effect of alpha-cypermethrin on a local freshwater non-target green alga Chlorella sp. NC-MKM in terms of its protein levels. This was achieved by exposing Chlorella sp. NC-MKM to an EC50 concentration of alpha-cypermethrin for 1day, followed by the two-dimensional (2-D) gel electrophoresis and MALDI-TOF MS. Fifty-three proteins, which had showed significant differential accumulation (> 1.5 fold, P < 0.05) after exposure to alpha-cypermethrin, were considered as differentially accumulated proteins (DAPs). These DAPs were further divided into several functional categories, and the expressions of each in control and treatment samples were compared. Comparison revealed that alpha-cypermethrin exposure affects the accumulation of proteins related with photosynthesis, stress response, carbohydrate metabolism, signal transduction and transporters, translation, transcription, cell division, lipid metabolism, amino acid and nucleotide biosynthesis, secondary metabolites production, and post-translational modification, and thus rendered the tested algal isolate sensitive toward this pesticide. The overall findings of this research thus offer a fundamental understanding of the possible mechanism of action of the insecticide alpha-cypermethrin on the microalga Chlorella sp. NC-MKM and also suggest potential biomarkers for the investigation of pesticide exposed microalgae.

Nghiên cứu sử dụng chế phẩm Altach 5EC xử lý rễ hành Allium fistulosum L góp phần nâng cao hiệu quả bài thực hành “đột biến cấu trúc nhiễm sắc thể” môn Di truyền - Tiến hóa tại Khoa Sinh học Trường Đại học Vinh

In this study, a commercial insecticide, Altach 5EC, has been used to investigate its cytotoxic effects on chromosomes and mitosis of cells in the root tip of Allium fistulosum L. The result indicated that Altach 5EC which contaning two different concentrations of alphacypermethrin (0,047 mg/ml and 0,062 mg/ml) were used to treat the root tips for 8 hours led to a decrease in the mitosis index compared to the negative control. Especially, various types of chromosomal mutations were observed such as broken chromosomes, chromosomal bridges, and slow-moving chromosomes. At the same time, numerous disturbances of mitosis were observed, which added the data for the practice lesson of Mitosis. These disturbances included sticky chromosomes, metaphase disturbance, fault polarization in anaphase and telophase, and sticky metaphase. The study revealed that Altach 5EC is a suitable commercial insecticide for effectively treating the roots of Allium fistulosum L. in both the “Chromosomal Structural Mutations” and “Mitosis” lessons within Genetics - Evolution subject at Biology Department, Vinh University.

Efficacy of Nets Coated with Different Concentrations of Alpha-Cypermethrin against Two Major Pests of Stored Tobacco

In the present study, we examined the insecticidal effect of Carifend® (BASF AG, Ludwigshafen, Germany; 163.2 mg m−2), an alpha-cypermethrin-coated polyester net, as well as Carifend-like nets containing different rates of alpha-cypermethrin, specifically 10, 30, 80, and 325 mg m−2, against two major stored tobacco insect pests, i.e., Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae) and Ephestia elutella (Hübner) (Lepidoptera: Pyralidae). The nets were glued at the bottom of plastic Petri dishes, and adults of L. serricorne and E. elutella were exposed to the nets for different exposure times (e.g., 1, 5, 15, 30, 60, 90, and 120 min, as well as 12 and 24 h). After each exposure interval, insect mortality was recorded, whereas after the final evaluation, alive individuals were transferred to untreated dishes, and delayed mortality was recorded after an additional period of 1, 3, 5, and 7 d. Based on our results, efficient control of both insect species was achieved with all nets, even the one containing a lower concentration of alpha-cypermethrin (10 mg m−2). High mortality rates were recorded for all treatments, indicating that even short exposure of adults of both tested species to the alpha-cypermethrin-coated nets tested can lead to mortality. For instance, at 30 mg m−2, mortality of E. elutella reached 40% 1 d after exposure for 30 min. Moreover, at the highest concentration (325 mg m−2), mortality reached 70% and 99% 7 d post exposure for 24 h of L. serricorne and E. elutella, respectively. Based on these data, Carifend®, as well as the rest of the Carifend-like nets tested, can be used as an alternative insecticide method for the control of two major stored tobacco insect species, i.e., L. serricorne and E. elutella. Insecticide treated nets can be used in areas in which fumigants and contact insecticides are not accessible.

Entomopathogenic nematodes for control of potato tuber moth (Phthorimaea operculella [Zeller], (Lepidoptera: Gelechiidae) in infested tubers

The potato tuber moth (PTM), Phthorimaea operculella, is one of the most economically important potato pests worldwide. In the present study, the potential of Steinernema carpocapsae for controlling PTM in infested potato tubers was evaluated and compared with S. feltiae and the pyrethroid alpha-cypermethrin. The results for efficacy percentage showed that S.carpocapsae [72.52 and 65.49% for 12.6 × 106 and 6.2 × 106 infective juveniles (IJs), respectively] and S. feltiae (69.56% for 12.6 × 106 IJs) were as efficient as alpha-cypermethrin (66.76% for10 mg ai L−1). Both concentrations of alpha-cypermethrin and S. carpocapsae showed the least tuber damage with no significant differences (33.5–39.33%), while it was as high as the control (59.26%) in both concentrations of S. feltiae. The median lethal concentration (LC50) value for S. carpocapsae [5.46 (4.41–6.55) IJs per prepupa] was significantly lower than S. feltiae [8.52 (7.12-10.20) IJs per prepupa] which confirms the superiority of S. carpocapsae. These promising findings introduce S. carpocapsae as a part of the potato tuber protection programs for treating the tubers. Accordingly, EPNs can be considered as an appropriate alternative to synthetic chemicals for PTM control.

Assessment of biochemical, hematological and behavioral biomarkers of Cyprinus carpio on exposure to a type-II pyrethroid insecticide Alpha-cypermethrin

This study assessed some important physiological biomarkers of freshwater edible fish Cyprinus carpio following exposure to 10 % (T1) and 20 % (T2) sublethal concentrations of Alpha-cypermethrin (A-cyp) over a total period of 45 days. Behavioral responses were noticed and Kaplan-Meier survival curves were prepared during acute toxicity study. Total serum protein concentration, total erythrocyte count, hemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and total leukocytes count were decreased significantly (p < 0.05), while the blood glucose, total serum lipid concentration, and clotting time were increased significantly (p < 0.05) over control. The most affected fish group and most significantly altered biomarker under toxic stress of A-cyp were identified using integrated biomarker response (IBR). The biomarker response index (BRI) values measured the overall health status of the treated fish and indicated that moderate adverse effects were exerted on the fish group exposed to T2 for 45 days.

Susceptibility of phlebotomine sandflies (Diptera: Psychodidae) collected in the field, to alpha-cypermethrin in four municipalities endemic to leishmaniasis.

ABSTRACTAlthough the chemical control against leishmaniasis began in 1953 in Brazil, little information is available on how this strategy has affected populations of phlebotomine sandflies in the field. The objective of this study was to analyze the susceptibility profile of four populations of phlebotomine sandflies to the insecticide alpha-cypermethrin. Sandflies collected in field in four Brazilian municipalities were evaluated using CDC bottles in different concentrations of alpha-cypermethrin. A total of 1,186 phlebotomine sandflies were used in the bioassays. The LD50 ranged from 1.48 to 2.57 ug/mL in the field populations. For a dose of 5 ug/mL of alpha-cypermethrin, the LT50 and LT95 ranged from 17.9 to 27.5 minutes, and LT95 from 39.7 to 61.5 minutes, respectively. All the populations studied were highly susceptible to the insecticide alpha-cypermethrin. Routine studies are needed to detect changes in sandflies susceptibility to insecticides.

Insecticidal activity of alpha-cypermethrin against small banded pine weevil Pissodes castaneus (Coleoptera: Curculionidae) in forest plantations and thickets

Abstract Scots pine (Pinus sylvestris) plantations and thickets damaged by biotic and abiotic factors are particularly attractive to small-banded pine weevil Pissodes castaneus, whose larvae excavate feeding tunnels in the stems of young trees, causing their death. There are no chemical methods that can be applied to protect forest plantations and thickets against this pest. Therefore, the studies were undertaken aimed at the assessment of the efficacy of alpha-cypermethrin used to reduce the numbers of this pest within restock areas. The scope of work included laboratory and field estimation of insecticidal activity of alpha-cypermethrin. In laboratory, the beetles of P. castaneus were reared on P. sylvestris twigs treated with five concentrations of alpha-cypermethrin (0.0001–1%) formulated as Fastac Forest 15 SC. Insect mortality was calculated during 7-day rearing and median lethal concentration LC50 was calculated. The field treatments consisted of spraying of four-year old Scots pines with the insecticide in concentrations of 2% and 4%. In laboratory conditions, the insecticide used at five different concentrations caused a 7–95% mortality of the beetles (LC50 = 0.266%), while field sprays resulted in a 1.5–3.5-fold reduction in the colonization of trees and in higher pest mortality rates. The results indicate the possibility of using of alpha-cypermethrin in protecting the forest against P. castaneus and can be the basis for the development of chemical method used in the forestry practice.

Microbial degradation of alpha-cypermethrin in soil by compound-specific stable isotope analysis

To assess microbial degradation of alpha-cypermethrin in soil, attenuation of alpha-cypermethrin was investigated by compound-specific stable isotope analysis. The variations of the residual concentrations and stable carbon isotope ratios of alpha-cypermethrin were detected in unsterilized and sterilized soils spiked with alpha-cypermethrin. After an 80 days’ incubation, the concentrations of alpha-cypermethrin decreased to 0.47 and 3.41mg/kg in the unsterilized soils spiked with 2 and 10mg/kg, while those decreased to 1.43 and 6.61mg/kg in the sterilized soils. Meanwhile, the carbon isotope ratios shifted to −29.14±0.22‰ and −29.86±0.33‰ in the unsterilized soils spiked with 2 and 10mg/kg, respectively. The results revealed that microbial degradation contributed to the attenuation of alpha-cypermethrin and induced the carbon isotope fractionation. In order to quantitatively assess microbial degradation, a relationship between carbon isotope ratios and residual concentrations of alpha-cypermethrin was established according to Rayleigh equation. An enrichment factor, ϵ=−1.87‰ was obtained, which can be employed to assess microbial degradation of alpha-cypermethrin. The significant carbon isotope fractionation during microbial degradation suggests that CSIA is a proper approach to qualitatively detect and quantitatively assess the biodegradation during attenuation process of alpha-cypermethrin in the field.

Effectiveness and durability of Interceptor® long-lasting insecticidal nets in a malaria endemic area of central India.

BackgroundIn the present study, Interceptor®, long-lasting polyester net, 75 denier and bursting strength of minimum 250 kPa coated with alpha-cypermethrin @ 200 mg/m2 was evaluated for its efficacy in reducing the mosquito density, blood feeding inhibition and malaria incidence in a tribal dominated malaria endemic area in Chhattisgarh state, central India. Its durability, washing practices and usage pattern by the community was also assessed up to a period of three years.MethodsThe study was carried out in two phases. In the first phase (September 2006 to August 2007), 16 malaria endemic villages in district Kanker were randomized into three groups, viz. Interceptor net (LN), untreated polyester net (100 denier) and without net. Malaria cases were detected by undertaking fortnightly surveillance by home visits and treated as per the national drug policy. Mosquito collections were made by hand catch and pyrethrum space spray methods from human dwellings once every month. Slide positivity rate (SPR) and malaria incidence per 1000 population (PI) were compared between the three study arms to assess the impact of use of Interceptor nets. Simultaneously, wash resistance studies were carried out in the laboratory by doing cone bioassays on Interceptor LNs washed up to 20 times. Activities undertaken in second Phase (April 2008 to October 2009) after an interval of about 18 months post-net distribution included questionnaire based surveys at every six months, i.e. 18, 24, 30 and 36 months to observe durability, usage pattern of LNs and washing practices by the community. After 36 months of field use, 30 nets were retrieved and sampled destructively for chemical analysis.ResultsInterceptor nets were found effective in reducing the density, parity rate and blood feeding success rate of main malaria vector Anopheles culicifacies as compared to that in untreated net and no net villages. SPR in LN villages was 3.7% as compared to 6.5% in untreated and 11% in no net villages. PI in LN villages was 16.4 in comparison to 24.8 and 44.2 in untreated polyester net and no net villages respectively. In surveys carried out after three years of initial distribution, 78.7% (737/936) nets were still in possession with the households, of which 68% were used every night. An. culicifacies mortality was >80% in cone bioassays done on LNs washed up to 20 times in laboratory. Mean alpha-cypermethrin content was 43.5 ± 31.7 mg/m2 on Interceptor LNs withdrawn after three years of household use against the baseline specification of 200 mg/m2. A gradual increase in the proportion of holed nets was observed with the increased period of usage.ConclusionInterceptor nets were highly effective in reducing vector densities as well as malaria incidence in the study villages. Availability of 78% nets with the households in usable condition clearly indicated durability of Interceptor LNs up to three years in the rural setting of India. The nets were found to contain an effective concentration of alpha-cypermethrin against malaria vector after three years of household use.

Evidence for a useful life of more than three years for a polyester-based long-lasting insecticidal mosquito net in Western Uganda

BackgroundLong-lasting insecticidal nets (LLIN) are now standard for the prevention of malaria. However, only products with recommendation for public use from the World Health Organization should be used and this evaluation includes the assessment of net effectiveness after three years of field use. Results for one of the polyester-based products, Interceptor® is presented.MethodsIn five villages, 190 LLIN and 90 nets conventionally treated with the insecticide alpha-cypermethrin at 25 mg/m2 were distributed randomly and used by the families. Following a baseline household survey a net survey was carried out every six months to capture use, washing habits and physical condition of the nets. Randomly selected nets were collected after 6, 12, 24, 36 and 42 months and tested for remaining insecticide content and ability to knock-down and kill malaria transmitting mosquitoes.ResultsDuring the three and a half years of observation only 16 nets were lost to follow-up resulting in an estimated attrition rate of 12% after three and 20/% after 3.5 years. Nets were used regularly and washed on average 1.5 times per year. After three and a half years 29% of the nets were still in good condition while 13% were seriously torn with no difference between the LLIN and control nets. The conventionally treated nets quickly lost insecticide and after 24 months only 7% of the original dose remained (1.6 mg/m2). Baseline median concentration of alpha-cypermethrin for LLIN was 194.5 mg/m2 or 97% of the target dose with between and within net variation of 11% and 4% respectively (relative standard deviation). On the LLIN 73.8 mg/m2 alpha-cypermethrin remained after three years of use and 56.2 mg/m2 after three and a half and 94% and 81% of the LLIN still had > 15 mg/m2 left respectively. Optimal effectiveness in bio-assays (≥95% 60 minute knock-down or ≥ 80% 24 hour mortality) was found in 83% of the sampled LLIN after three and 71% after three and a half years.ConclusionsUnder conditions in Western Uganda the tested long-lasting insecticidal net Interceptor® fulfilled the criteria for phase III of WHO evaluations and, based on preliminary criteria of the useful life, this product is estimated to last on average between three and four years.

Locomotor Behavioral Responses of Anopheles minimus and Anopheles harrisoni to Alpha-Cypermethrin in Thailand

Excito-repellency responses of 3 test populations, representing 2 sibling species within the Minimus Complex, Anopheles minimus and An. harrisoni, were characterized for contact irritant and noncontact repellent actions of chemicals during and after exposure to alpha-cypermethrin at half the recommended field (0.010 g/m2), the recommended field (0.020 g/m2), and double the recommended field concentration (0.040 g/m2), using an excito-repellency escape chamber system. Two field populations of An. minimus and An. harrisoni collected from the malaria-endemic areas in Tak and Kanchanuburi provinces in western Thailand, respectively, were tested along with a laboratory population of An. minimus maintained since 1993. Females of all 3 test populations rapidly escaped after direct contact with treated surfaces for each concentration. In general, increased escape responses in the An. minimus test populations were proportionate to increased insecticide dosages. The greatest escape response for An. harrisoni was observed at the operational field concentration of alpha-cypermethrin. The noncontact repellency response to alpha-cypermethrin was comparatively weak for all 3 test populations, but significantly different from each paired contact test and respective noncontact controls. We conclude that strong contact irritancy is a major action of alpha-cypermethrin, whereas noncontact repellency plays no role in the escape responses of 2 species in the Minimus Complex in Thailand.

The in vitro genotoxic effects of a commercial formulation of α‐cypermethrin in human peripheral blood lymphocytes

alpha-Cypermethrin, a highly active pyrethroid insecticide, is effective against a wide range of insects encountered in agriculture and animal husbandry. The potential genotoxicity of a commercial formulation of alpha-cypermethrin (Fastac 100 EC, containing 10% alpha-cypermethrin as the active ingredient) on human peripheral lymphocytes was examined in vitro by sister chromatid exchange (SCE), chromosomal aberrations (CAs), and micronucleus (MN) tests. The human lymphocytes were treated with 5, 10, 15, and 20 microg/ml of alpha-cypermethrin for 24- and 48-hr. alpha-Cypermethrin induced SCEs and CAs significantly at all concentrations and treatment times and MN formation was significantly induced at 5 and 10 microg/ml of alpha-cypermethrin when compared with both the control and solvent control. Binuclear cells could not be detected sufficiently in the highest two concentration of alpha-cypermethrin (15 and 20 microg/ml) for both the 24- and 48-hr treatment times. alpha-Cypermethrin decreased the proliferation index (PI) at three high concentrations (10, 15, and 20 microg/ml) for both treatment periods as compared with the control groups. In addition, alpha-cypermethrin reduced both the mitotic index (MI) and nuclear division index (NDI) significantly at all concentrations for two treatment periods. The PI and MI were reduced by alpha-cypermethrin in a concentration-dependent manner during both treatment times. In general, alpha-cypermethrin showed higher cytotoxic and cytostatic effects than positive control (MMC) at the two highest concentrations for the 24- and 48-hr treatment periods. The present study is the first to report the genotoxic and cytotoxic effects of commercial formulation of alpha-cypermethrin in peripheral blood lymphocytes.

Efficacy and environmental fate of alphacypermethrin applied to rice fields for the control of chironomid midge larvae (Diptera: Chironomidae)

Chironomid midge larvae are the most important pests affecting the establishment of aerially sown rice crops in New South Wales (NSW). The pyrethroid insecticide alphacypermethrin was evaluated for the control of chironomid midge larvae in small plot field trials at Yanco Agricultural Institute during the 1997–1998 and 1998–1999 rice seasons. Treatments were applied at sowing (6 days after flooding) in both trials. In the 1997–1998 trial, alphacypermethrin applied as an emulsifiable concentrate formulation at 10, 20, and 30 g active ha −1 provided between 54 and 73% control of target Chironominae in the first 19 days after application (DAA), whilst a chlorpyrifos standard treatment (75 g active ha −1) also provided 73% control. Populations of Chironominae were very low during the 1997–1998 season (estimated control density 14 DAA approximately 485 larvae m −2), and control was not reflected in improved plant establishment. In the 1998–1999 season target Chironominae, predominantly Chironomus tepperi Skuse, were far more abundant (estimated control density 14 DAA approximately 13 100 larvae m −2). Alphacypermethrin provided >99% control of Chironominae for 19 DAA at all rates evaluated (6, 10 and 20 g active ha −1), whilst the chlorpyrifos standard (75 g active ha −1) gave 97% control over the same period. Plant establishment 30 DAA averaged 23 plants m −2 in the control bays, from 169 to 188 plants m −2 in the alphacypermethrin bays, and 204 plants m −2 in the bays containing the chlorpyrifos standard. Differences in plant establishment between the alphacypermethrin and chlorpyrifos treatments were not significant ( P>0.05). Results indicate that alphacypermethrin applied at between 6 and 10 g active ha −1 will be equal or superior to chlorpyrifos (75 g active ha −1) for the control of chironomid larvae during rice crop establishment. Concentrations of alphacypermethrin in the water column and sediment were monitored during each trial. Concentrations in water for the 20 g active ha −1 rate ranged from 0.23 to 0.41 μg l −1 1 DAA down to 0.008 μg l −1 at 18 DAA, whilst at the 6 g active ha −1 rate alphacypermethrin concentrations declined to below the detection limit (0.001 μg l −1) at 18 DAA. Surface sediments (top 2 cm) still contained measurable concentrations of alphacypermethrin at 25 DAA (e.g. 29 μg kg −1 for 20 g active ha −1 rate, 1997–1998 trial). No alphacypermethrin residues were detected in plant samples taken 42 days after treatment, or in grain or forage samples at harvest (1997–1998 trial, detection limit 20 μg kg −1).

Kinetic disposition of an aqueous formulation of alphacypermethrin applied to the dorsal mid-line of sheep with long wool and its effect on lice

A group of 5 adult Merino sheep with fleeces about 70 mm long (7-months growth of wool) was treated with a topical formulation of the synthetic pyrethroid insecticide, alphacypermethrin, applied to the dorsal mid-line. Insecticide concentrations at the tip, middle and base of wool staples collected from meridians along the back, upper and lower flanks were measured at intervals from 1 to 98 days after treatment. Some movement of the alphacypermethrin from the back to the lower body occurred within 24h after treatment, but despite careful application of the insecticide there was wide variation in the concentration between and within meridians. The majority of the alphacypermethrin remained close to the dorsal mid-line and near the tip of the staple. There were significant differences in the concentration between the tip, middle and base segments of the staples in the back and lower flank meridians ( P < 0.05). Despite exposure of the sheep to normal weathering, there was no significant difference in the concentration of alphacypermethrin between samples collected at day 1 or day 98 after treatment ( P > 0.05). Numbers of pyrethroid-susceptible lice surviving exposure in vitro for 20 h differed significantly between samples collected at different times after treatment ( P < 0.05). The numbers of lice surviving in samples collected within 28 days after treatment tended to be lower than in those collected from 28 to 98 days but, in some samples, regardless of time after treatment, lice survived for 20 h in wool taken from parts of the fleece that contained high concentrations of alphacypermethrin.