Using ultraviolet irradiation for removal of malathion pesticide in water

Organophosphorus pesticides are one of the most consumable poisons. Such poisons can enter water sources by different routes. Since consuming some drinking water containing an amount of poison higher than the standard level, causes undesirable effects on human health. This research aimed to study the effectiveness of eliminating malathion from water by ultraviolet irradiation [UV] mercury lamp with a medium pressure. In this experimental- applied study, variants of initial pHs and initial concentrations and exposure times were investigated. Initial concentrations of malathion were 0.5, 1 and 2 mg/l. The samples were then exposed to UV irradiation interruptedly the time periods of 10, 20, 30, 40, 50 and 60 minutes. The UV lamp used in the reactor was medium pressure [irradiation intensity= 200 W/m[2]]. The amounts of malathion were determined before and after the irradiation by HPLC instrument. Moreover, the results obtained from the study were analyzed using SPSS software and ANOVA and t-test statistical trials. The minimum reduction occurs at 10 min [%46] and the maximum reduction in 60 min [% 87.25] [P < 0.05]. In addition, the effectiveness of irradiation process decreases with increasing the poison concentration [P < 0.001]. However, the efficiency of the process increases with pH increase. The results show the most effectiveness were achieved at 60 min and 0.5 mg/l and pH= 9. Therefore, the application of UV reactors could be considered as an appropriate method

Removal of malathion insecticide from water by employing acoustical wave technology

Organophosphorus pesticides are one of the most prevalent usages for pest control in the country. Such pesticides enter into water sources by different routes. Since drinking of contaminated water at the higher doses than the standard level, may causes undesirable effects to human health and ecosystem. The object of this research was to investigate the effect of various parameters including time, power and concentration on sonodecomposition of malathion insecticide in the water. The sonochemical degradation of malathion was investigated using acoustic wave technology [AWT]. AWT with 130 kHz was used to study the decomposition of insecticide solution. Samples were analyzed using HPLC at different intervals times. Effectiveness of AWT at different times [20, 40, 60, 80, 100, and 120 minutes], concentrations of malathion at 2, 4 and 8 mg/L as well as powers of device [300W, 400W, 500W] are compared. These findings showed that the degradation of the malathion insecticide at lower concentrations was greater in comparison to higher concentrations. Also, there was positive correlation between power increasing and the ability to malathion degradation. The sonodegradation of malathion at different concentrations and powers was successfully achieved. It has been shown that acoustical wave technology can be used to reduce the concentration of dissolved insecticide using high frequency

Repellency effects of essential oils of myrtle [myrtus communis], marigold [Calendula officinalis] compared with DEET against anopheles stephensi on human volunteers

Malaria and leishmaniasis are two most significant parasitic diseases which are endemic in Iran. Over the past decades, interest in botanical repellents has increased as a result of safety to human. The comparative efficacy of essential oils of two native plants, myrtle [Myrtus communis] and marigold [Calendula officinalis] collected from natural habitats at southern Iran was compared with DEET as synthetic repellent against Anopheles stephensi on human subjects under laboratory condition. Essential oils from two species of native plants were obtained by Clevenger-type water distillation. The protection time of DEET, marigold and myrtle was assessed on human subject using screened cage method against An. stephensi. The effective dose of 50% essential oils of two latter species and DEET were determined by modified ASTM method. ED[50] and ED[90] values and related statistical parameters were calculated by probit analysis. The protection time of 50% essential oils of marigold and myrtle were respectively 2.15 and 4.36 hours compared to 6.23 hours for DEET 25%. The median effective dose [ED[50]] of 50% essential oils was 0.1105 and 0.6034 mg/cm[2] respectively in myrtle and marigold. The figure for DEET was 0.0023 mg/cm[2]. This study exhibited that the repellency of both botanical repellents was generally lower than DEET as a synthetic repellent. However the 50% essential oil of myrtle showed a moderate repellency effects compared to marigold against An. stephensi

Application of acoustical processor reactors for degradation of diazinon from surface water

Since organophosphorus pesticides are widely used for industry and insect control in agricultural crops, their fate in the environment is very important. Pesticide contamination of surface water has been recognized as a major contaminant in world because of their potential toxicity towards human and animals. The objective of this research was to investigate the influence of various parameters including the iniluence oftime. power, and initial concentration on degradation of diazinon pesticide. The sonochemical degradation of diazinon was investigated using acoustical processor reactor. Acoustical processor reactor with 130 kHz was used to study the degradation of pesticide solution. Samples were analyzed using HPLC at different time intervals. Effectiveness of APR at different times [20, 40, 60, 80, 100, and 120 min], concentrations [2. 4 and 8 mg/L] and powers [300W, 400W, 500W] were compared. The degradation of the diazinon at lower concentrations was greater in comparison to higher concentrations. There was also direct correlation between power and diazinon degradation. In addition, when the power increased, the ability to degraded diazinon increased. The sonodegradation of diazinon pesticide at different concentrations and powers was successfully provided. It has been shown that APR can be used to reduce the concentration of dissolved pesticide using high frequency

Epidemiology of head lice infestation in primary school pupils, in Khajeh city, east Azerbaijan Province, Iran

Pediculus capitis [Anoplura: Pediculidae] or head louse is an obligate ectoparasite transmitted mainly through physical contact. This study was conducted to survey the prevalence of head lice infestation rate and some risk factors in Primary School pupils, in Khajeh City East Azerbaijan Province, Iran We selected 20 primary schools of Khajeh City during 2008 and 2009. Totally 500 pupils including 200 boys and 300 girls from all grade 1-5 were selected by multistage, systematic random sampling in rural areas of Khajeh City and were examined for lice. In addition, a standard questionnaire recorded information about demographic features of each pupil. Results were analyzed by SPSS software. The total prevalence of head lice infestation in this study was 4.8%. and the prevalence rate was significantly higher in girls [6.66%] than in boys [2%]. Epidemiological factors such as: sex, school grade, family size, parent's education, type of house, hair washing [per week], number of using comb per day, were evaluated and results showed significant difference in head lice infestation and sex, school grade, family size, father education, and type of house [P<0.05]. Pediculosis is a public health problem in many parts of the world, and due to the higher prevalence of pediculosis in crowded families, family by lower levels of father's education and socioeconomic status in our study and rural area, it is necessary to give health education for families to prevent of pediculosis in this area

Effectiveness of ultrasound and ultraviolet irradiation on degradation of carbaryl from aqueous solutions

Carbaryl [1-naphthyl-N-methyl carbamate] is a chemical in the carbamate family used chiefly as an insecticide. It is a cholinesterase inhibitor and is toxic to humans and classified as a likely human carcinogen. In the present study, the degradation of the carbaryl pesticide was investigated in the laboratory synthetic samples of tap water, in the effect of sonolysis and photolysis processes. This study was conducted during 2006-7 in Chemistry and Biochemistry of Pesticides Laboratory in Tehran University of Medical Sciences [TUMS] in Iran. The carbaryl [80%] was used for preparing samples. First concentration of all samples were 4 mg/l. Sonochemical examinations in ultrasound reactor was done in two 35, 130 Hz, and 100 w, and three time. Photolysis examinations has done in the effect of 400 w lamp and moderate pressure and 6 time, then the amount of pesticide in the samples has been measured by the High Performance Thin Layer Chromatography [HPTLC] method. The highest degradation in photolysis process after 1 hour in the 35 KHz was 35%, and in the 130 KHz was 63%. Degradation of carbaryl at 130 KHz is higher than 35 KHz at the same time. Carbaryl elimination was increased by arise frequency and exposure time. After 8 min in photolysis, 100% omitting has been showed. Degradation of carbaryl in high frequency ultrasound wavelength was more than low frequency. Degradation of carbaryl in water, combination of high frequency ultrasound wave length and UV irradiation was considerably more effective than ultrasound or ultraviolet irradiation alone

Determination of organophosphorus insecticide residues in the rice paddies

In most rice paddies in Mazandaran Province, diazinon is applied to control Chilo suppressalis. Due to the extensive application of insecticides in the rice paddies of the Caspian coasts of Iran, this investigation was carried out on the rice fields in order to obtain the necessary data and information on the concentration of insecticide residues. A total of 125 samples were taken from five areas of Amol township in 2007. Then, according to the analysis of variance procedures, the water samples were statistically analyzed after the spraying of diazinon. Results indicate that the insecticide was used frequently to control stem boring caterpillar of rice. The residuals of this toxic chemical were observed in the majority of stations from the day after the spraying until one to two months later. The greatest level of diazinon was observed in station 1 in amount of 1.14 ppm. This study revealed that the physical and chemical properties of the studied diazinon such as fumigation characteristic as well as the ecological conditions and soil type influence the reduction and eventual removal of the insecticides during the cultivation and harvest periods

High performance thin layer chromatography analysis of deltamethrin residue on the impregnated bed nets during a leishmaniasis control program in Iran

The control of leishmaniasis, a tropical neglected disease, has been concern of Iranian health authorities due to the increasing number of cases during the last two decades. The objective of this study was to determine deltamethrine residue on the impregnated bed nets using HPTLC technique in a leishmaniasis control program in Iran. During this experimental study, a total of 130 small pieces of polyester netting were sewn to top, upper, and lower sides of some bed nets and then were impregnated with deltamethrin .The treated bed nets were distributed in Isfahan and Mashhad areas in April 2003. The samples were cut randomly after impregnation intervals. Deltamethrin was extracted using acetone from samples and the extract was applied for spotting onto plates. The plates were developed with n-hexane: ethyl acetate, 90+10[v/v], as a mobile phase in a Camage chamber. The qualifying of residue was observed in UV cabinet with lambda =254 nm wavelength. Data were analyzed using SPSS version 11.5. and Stata Version 8. A three way ANOVA was used to compare the means of deltamethrin residue in each area, group and measuring time. The Kruskal-Wallis test was used to compare the means of residue for each of these factors with the control separately. The retardation factor of deltamethrin was calculated 0.50 +/- 0.02. The residues of deltamethrin persisted well on impregnated nets at least for 15 weeks after impregnation. No significant difference could be detected in the loss of residue of insecticide in comparison to measuring times and positions of sampling pieces on the bed nets in these areas. Based on the results of the present study the use of HPTLC technique is recommended instead of other chromatographic methods for analysis of insecticide residue on the impregnated bed nets

study on rodent ectoparasities in Bandar Abbas: the main economic southern seaport of Iran

Rodents are one of the main health problems in the cities, especially in coastal area. These animals make economic damages and are potential health dangers in Bandar Abbas, the main economic southern port of Iran. In this study, rodents were captured from different parts of the city, before and after a control program during 2003-2004, transferred to the laboratory, identified and examine for ecto-parasites. Totally 105 rodents demonstrating four species: Rattus rattus [3%], R. norvegicus [78%], Mus musculus [3%] and Tatera indica [16%], were captured before the control program. The most frequency was observed in Ayatollah Ghafari quarter, 10 rodents per 24 traps. After 12 months, the duration of control program, rodents were re-captured to assessment the success of control activity. In this stage 35 small mammals demonstrated four species were obtained: R. norvegicus [51.4%], R. rattus [37.1%], T.indica [8.6%] and one weasel [2.9%]. We found the most frequency in Khoon-sorkh quarter with 6 rodents per 24 traps. The identified ectoparasites were Xenopsylla buxtoni, Rhipicephalus sp,. Polyplax gerbilli, Haplopleura captiosa, Ornithonyssus bacoti, Laelaps nuttalli, Dermanyssus americanus, Dermanyssus sanguineus, Haemolaelaps glasgowi and Echinolaelaps echidninus. The number of rodents reduced to one third after control program, shows the relative success of this program [p<0.05]

Comparison of Permethrin and Fipronil toxicity against German cockroach [Dictyoptera: Blattellidae] strains

Control of insect pests of agriculture, economic, and medical importance usually focuses on the use of insecticides. The susceptibility levels of eleven strains of German cockroaches, Blattella germanica [L.], were compared with a standard susceptible strain against permethrin and fipronil. The strains were collected from nine infested students' dormitories and two infested hospitals in Tehran, capital of Iran. The susceptible strain showed LD50 of 0.43 micro g and 0.96 ng for permethrin and fipronil respectively. Comparison of the resistance ratio of collected strain with susceptible strain showed resistance ratios of 8.6 to 17.7-folds for permethrin and 1.5 to 2.6-folds for fipronil, respectively. The result of this investigation indicated that the all strains were resistant to permethrin. Resistance spectrum of fipronil to permethrin showed different pattern of susceptibility to fipronil, indicating that there was no relationship between resistance to permethrin and fipronil

Effect of fipronil on permethrin sensitive and permethrin resistant strains of blattella germanica

Strategies to manage resistance to insecticides have usually been designed when resistance has already been developed. However, if the likelihood of resistance development to novel insecticides can be predicted before their use, it should be possible to establish an effective resistance management program. The current study was designed to investigate the effect of fipronil against permethrin sensitive and permethrin resistant strains of Blattella germanica [L.] for effective control of this pest in Iran in the future. In order to conduct this study eleven feral German cockroach strains were collected from infested student dormitories of Tehran University of Medical Sciences, Sanatee Sharif, Tarbiat Modares and Tehran Universities and also residential Saman Apartments, and two infested hospitals in Tehran. Their sensitivity to permethrin and fipronil were compared with that of a standard susceptible strain. Tests were conducted on newly emerged adult males [ultimately 21 years old] by topical application. LD[50]'s of permethrin and fipronil for the susceptible strain were 0.43/micro g and 0.96 ng respectively. The resistance of feral strains to permethrin was 8.6 to 17.7 times as much as that of the susceptible strain. According to this investigation all strains are resistant to permethrin, whereas resistance rates of the strains from Bustan-10, Zanjan Fatemiyeh dormitories and residential Saman Apartments were 2 to 2.6 times more than that of the susceptible strain. Other strains were completely susceptible to fipronil. According to the results of this study and considering ever-increasing infestation of human habitations by German cockroach and the resistance to insecticides; fipronil especially its toxic bait formulations can be regarded as the appropriate candidate to control this pest in Iran

efficacy of permethrin-treated military uniforms as a personal protection against culex pipiens [diptera: culicidae] and its environmental consequences

Naturally, there are different species of Culex mosquitoes in Iran. Culex pipiens complex is widespread in many parts of the country, specially in urban areas. In spite of this fact that Cx. pipiens species is the vector of some orboviruses and filariasis in many countries of the World, it does not have an important role in transmission of diseases in Iran. This species can easily reproduce in urban areas, due to the infection of surface waters and presence of sewage canals. The importance of Cx.pipiens for mankind is in fact, its biting and nuisance, specially at sleeping time. In this study, six types of current military uniforms of Iran's army were treated by permethrin [0.125 mg. permethrin [AI]/cm2] and examined against the biting of natural population of Cx.pipiens in urban areas in Tehran. Eight volunteer were selected for this study. Six of them put on the treated uniforms and the other two of them wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights July 2004. There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The average number of biting among who wore untreated uniforms [control] was 2.14 mosquito biting/min/person [128.2/hr], While it was 0.23 [13.8/hr] for who wore treated uniforms. The percent protection of treated uniforms, in comparison with untreated ones, was about 89%. The protection percent of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results of species identification among captured mosquitoes of a field study showed that about 95% of them are of Cx.pipiens species, and protection of treated uniforms against them, was estimated 87%. Moreover, as an accompaning environmental consequence a significant reduction in mosquito's density was seen

protection of permethrin-treated military uniforms against natural population of Culex bitaeniohynchus, Culex ritaeniorhynchus and Culex perexiguus [Diptera: Culicidae]

Personnel of military forces have close contact with the environment and can be bitten by insects and exposed to the related diseases, more than other people. The importance of Culex mosquitoes for mankind is in fact, its biting and nuisance, especially at sleeping time. In recent years, great progresses have occurred in protecting people, especially military personnel, against arthropod bites and vector-borne disease, using treated clothes with permethrin. In this study, the protection of permethrin-treated military uniforms against 3 species of Culex in a rural field of Iran has been examined. In this study, six types of current military uniforms of Iran were treated by permethrin [0.125mg permethrin [Al]/cm[2] and examined against the biting of natural population mosquitoes of rural areas of Kazeroon, Fars Province, south of Iran, namely Culex. Eight volunteers were selected for this study. Six of them put on the treated uniforms and the other two wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights of July 2004. There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The relative protection level of treated uniforms, in comparison with untreated ones, was about 88/2%. The protection percentage of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results showed that the relative protection percent of treated uniforms against species of Culex bitaeniohynchus, Cx. tritaeniorhynchus and Cx.perexiguus were 72.7, 87 and 89.8, respectively. The results of chemical analysis with High performance Thin Layer Chromatography [HPTLC] method, before and after field test, showed that in two weeks of study, there hasn't been any significant decrease in the amount of uniforms' permethrin. According to this study, using of permethrin-treated clothing is a useful technique, which makes a considerable protection against insects biting. Therefore using this technique is recommended for protecting military personnel or civilians, as an effective method against hematophagous insects

[ protection of permethrin-treated military uniforms against natural population of Culex bitaeniohynchus, Culex ritaeniorhynchus and Culex perexiguus [Diptera: Culicidae]]

Background: Personnel of military forces have close contact with the environment and can be bitten by insects and exposed to the related diseases, more than other people. The importance of Culex mosquitoes for mankind is in fact, its biting and nuisance, especially at sleeping time. In recent years, great progresses have been occurred in protecting people, especially military personnel, against arthropod bites and vector-borne disease, using treating clothes with permethrin. In this study, the protection of permethrin-treated military uniformsagainst 3 species of Culex in a rural field of Iran has been examined

Materials and Methods: In this study, six types of current military uniforms of Iran were treated by permethrin [0.125mg permethrin [Al]/cm[2]] and examined against the biting of natural population mosquitoes of rural areas of Kazeroon, Fars Province, south of Iran, namely Culex. Eight volunteers were selected for this study. Six of them put on the treated uniforms and the other two ones wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights of July 2004

Results: There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The relative protection level of treated uniforms, in comparison with untreated ones, was about 88/2%. The protection percentage of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results showed that the relative protection percent of treated uniforms against species of Culex bitaeniohynchus, Cx. tritaeniorhynchus and Cx. perexiguus were 72.7, 87 and 89.8, respectively .The results of chemical analysis with High performance Thin Layer Chromatography [HPTLC] method, before and after field test, showed that in two weeks of study, there hasn't been any significant decrease in the amount of uniforms' permethrin

Conclusions : According to this study, using of permethrin-treated clothing is a useful technique, which makes a considerable protection against insects biting. Therefor using this technique is recommended for protecting military personnel or civilian, as an effective method against hematophagous insects