Evaluación de la sensibilidad a organofosforados en poblaciones de Aedes aegypti (L. ) (Diptera: Culicidae) del departamento de La Guajira, Colombia / Evaluation of susceptibility to organophosphates in populations of Aedes aegypti (L. ) (Diptera: Culicidae) in La Guajira, Colombia

Introducción. El dengue es un problema de salud pública para el departamento de La Guajira. El control se ha enfocado en el vector con el uso de insecticidas, entre ellos los organofosforados. Objetivo. Evaluar el estado de la sensibilidad a insecticidas organofosforados de quince poblaciones de Aedes aegypti (L.) en el departamento de La Guajira, Colombia. Materiales y métodos. Se realizaron bioensayos para temefos, malatión y pirimifos- metil en larvas de tercer estadio y mosquitos adultos de Ae. aegypti en los municipios de Albania, Barrancas, Dibulla, Distracción, El Molino, Fonseca, Hatonuevo, La Jagua del Pilar, Maicao, Manaure, Riohacha, San Juan del Cesar, Uribia, Urumita y Villanueva, siguiendo la metodología de la Organización Mundial de la Salud (OMS) y la técnica de botellas usando la guía de los de los Centers for Disease Control and Prevention, respectivamente. Se determinó la sensibilidad por medio de la relación de resistencia a CL50 y CL95 (RRCL50, RRCL95) para temefos y a dosis y tiempo diagnóstico para temefos, malatión y pirimifos-metil en las poblaciones de campo evaluadas, usando como control la cepa sensible Rockefeller. Resultados. Las 15 poblaciones del departamento de La Guajira son sensibles a: temefos (relación de la resistencia a CL50<5,0; relación de resistencia a CL95<5,0; 98 a 100 % de mortalidad); pirimifos-metil (99 a 100 % de mortalidad) y malatión (100 % de mortalidad). Conclusión. Con base en los resultados obtenidos, es factible el uso de temefos, malatión y pirimifos-metil para el control de Ae. aegypti en las poblaciones evaluadas.

Introduction. Dengue is a public health problem in La Guajira region. Control has focused on the vector using insecticides, including organophosphates. Objective. To evaluate the state of susceptibility to organophosphates insecticides in fifteen Aedes aegypti (L.) populations in La Guajira, Colombia. Materials and methods. We collected samples of third-instar larvae and adult mosquitoes of Ae. aegypti in the municipalities of Albania, Barrancas, Dibulla, Distracción, El Molino, Fonseca, Hatonuevo, La Jagua del Pilar, Maicao, Manaure, Riohacha, San Juan del Cesar, Uribia, Urumita, Villanueva. Bioassays for temefos, malathion, and pirimiphos-methyl were carried out following the methodology of the World Health Organization, and the bottle technique using the guidance of the Centers for Disease Control and Prevention. Susceptibility to temefos was determined through the resistance ratio between lethal concentration 50 and lethal concentration 95; for the compounds temefos, malathion and pirimiphos-methyl, susceptibility was calculated using diagnostic dose and diagnostic time in the populations evaluated. Rockefeller susceptible strain was used as a control. Results. All evaluated populations of Ae. aegypti from La Guajira were found to be susceptible to temefos (ratio resistance to CL50<5.0; ratio resistance to CL95<5.0; 98 - 100 % mortality); pirimiphosmethyl (99 - 100 % mortality), and malathion (100 % mortality). Conclusion. Based on the results, the use of temefos, malathion, and pirimiphosmethyl is feasible for the control of Ae. aegypti in the evaluated populations.

Integrative analysis in toxicological assessment of the insecticide Malathion in Allium cepa L system / Análise integrativa na avaliação toxicológica do inseticida Malation no sistema Allium cepa L

For many centuries human populations have been suffering and trying to fight with disease-bearing mosquitoes. Emerging and reemerging diseases such as Dengue, Zika, and Chikungunya affect billions of people around the world and recently has been appealing to control with chemical pesticides. Malathion (MT) is one of the main pesticides used against mosquitoes, the vectors of these diseases. This study aimed to assess cytotoxicity and mutagenicity of the malathion for the bioindicator Allium cepa L. using a multivariate and integrative approach. Moreover, an appendix table was compiled with all available literature of insecticides assessed by the Allium cepa system to support our discussion. Exposures during 48h to 0.5 mg mL-¹ and 1.0 mg mL-¹ MT were compared to the negative control (distilled water) and positive control (MMS solution at 10 mg L-¹). The presence of chromosomal aberrations, micronuclei frequency, and mitotic index abnormalities was evaluated. Anaphase bridges were the alterations with higher incidence and presented a significantly elevated rate in the concentration of 0.5 mg mL-¹, including when compared to the positive control. The integrative discriminant analysis summarizes that MT in assessed concentrations presented effects like the positive control, corroborating its potential of toxicity to DNA. Therefore, it is concluded that MT in its pure composition and in realistic concentrations used, has genotoxic potential in the biological assessment of A. cepa cells. The multivariate integrative analysis was fundamental to show a whole response of all data, providing a global view of the effect of MT on DNA.

Por muitos séculos, as populações humanas sofrem e tentam combater os mosquitos transmissores de doenças. Doenças emergentes e reemergentes como Dengue, Zika e Chikungunya afetam bilhões de pessoas em todo o mundo e, recentemente, vem apelando ao controle com pesticidas químicos. O Malation (MT) é um dos principais pesticidas usados contra mosquitos, vetores dessas doenças. O objetivo deste estudo foi avaliar a citotoxicidade e a mutagenicidade do MT para o bioindicador Allium cepa L. usando uma abordagem multivariada e integrativa. Além disso, uma tabela suplementar foi compilada com toda a literatura disponível de inseticidas avaliada pelo sistema Allium cepa para apoiar nossa discussão. Exposições ao MT durante 48h a 0,5 mg mL-¹ e 1,0 mg mL-¹ foram comparadas a um controle negativo (água destilada) e um controle positivo (10 mg L-¹ de MMS). Foram avaliadas a presença de aberrações cromossômicas, frequência de micronúcleos e anormalidades no índice mitótico. As pontes anafásicas foram as alterações com maior incidência e apresentaram uma taxa significativamente elevada na concentração de 0,5 mg mL-¹, inclusive quando comparadas ao controle positivo. A análise discriminante integrativa resume que o MT nas concentrações avaliadas apresentou efeitos semelhantes ao controle positivo, corroborando seu potencial de toxicidade para o DNA. Portanto, conclui-se que o MT, em sua composição pura e nas concentrações realistas utilizadas, possui potencial genotóxico na avaliação biológica de células de A. cepa. A análise integrativa multivariada foi fundamental para mostrar uma resposta completa de todos os dados, fornecendo uma visão global do efeito da MT no DNA.

Integrative analysis in toxicological assessment of the insecticide Malathion in Allium cepa L. system / Análise integrativa na avaliação toxicológica do inseticida Malation no sistema Allium cepa L

Abstract For many centuries human populations have been suffering and trying to fight with disease-bearing mosquitoes. Emerging and reemerging diseases such as Dengue, Zika, and Chikungunya affect billions of people around the world and recently has been appealing to control with chemical pesticides. Malathion (MT) is one of the main pesticides used against mosquitoes, the vectors of these diseases. This study aimed to assess cytotoxicity and mutagenicity of the malathion for the bioindicator Allium cepa L. using a multivariate and integrative approach. Moreover, an appendix table was compiled with all available literature of insecticides assessed by the Allium cepa system to support our discussion. Exposures during 48h to 0.5 mg mL-1 and 1.0 mg mL-1 MT were compared to the negative control (distilled water) and positive control (MMS solution at 10 mg L-1). The presence of chromosomal aberrations, micronuclei frequency, and mitotic index abnormalities was evaluated. Anaphase bridges were the alterations with higher incidence and presented a significantly elevated rate in the concentration of 0.5 mg mL-1, including when compared to the positive control. The integrative discriminant analysis summarizes that MT in assessed concentrations presented effects like the positive control, corroborating its potential of toxicity to DNA. Therefore, it is concluded that MT in its pure composition and in realistic concentrations used, has genotoxic potential in the biological assessment of A. cepa cells. The multivariate integrative analysis was fundamental to show a whole response of all data, providing a global view of the effect of MT on DNA.

Resumo Por muitos séculos, as populações humanas sofrem e tentam combater os mosquitos transmissores de doenças. Doenças emergentes e reemergentes como Dengue, Zika e Chikungunya afetam bilhões de pessoas em todo o mundo e, recentemente, vem apelando ao controle com pesticidas químicos. O Malation (MT) é um dos principais pesticidas usados ​​contra mosquitos, vetores dessas doenças. O objetivo deste estudo foi avaliar a citotoxicidade e a mutagenicidade do MT para o bioindicador Allium cepa L. usando uma abordagem multivariada e integrativa. Além disso, uma tabela suplementar foi compilada com toda a literatura disponível de inseticidas avaliada pelo sistema Allium cepa para apoiar nossa discussão. Exposições ao MT durante 48h a 0,5 mg mL-1 e 1,0 mg mL-1 foram comparadas a um controle negativo (água destilada) e um controle positivo (10 mg L-1 de MMS). Foram avaliadas a presença de aberrações cromossômicas, frequência de micronúcleos e anormalidades no índice mitótico. As pontes anafásicas foram as alterações com maior incidência e apresentaram uma taxa significativamente elevada na concentração de 0,5 mg mL-1, inclusive quando comparadas ao controle positivo. A análise discriminante integrativa resume que o MT nas concentrações avaliadas apresentou efeitos semelhantes ao controle positivo, corroborando seu potencial de toxicidade para o DNA. Portanto, conclui-se que o MT, em sua composição pura e nas concentrações realistas utilizadas, possui potencial genotóxico na avaliação biológica de células de A. cepa. A análise integrativa multivariada foi fundamental para mostrar uma resposta completa de todos os dados, fornecendo uma visão global do efeito da MT no DNA.

Carcinogenicidade e mutagenicidade do malathion e seus dois análogos: uma revisão sistemática / Carcinogenicity and mutagenicity of malathion and its two analogues: a systematic review

Resumo O agrotóxico malathion vem sendo amplamente utilizado no mundo em programas de controle de arboviroses e em 2015 foi classificado pela Agência Internacional para Pesquisas em Câncer (IARC) como provável agente carcinogênico para seres humanos. Este trabalho objetivou a sistematização das evidências dos efeitos carcinogênicos e mutagênicos associados à exposição do malathion e seus análogos, malaoxon e isomalathion. A busca foi realizada nas bases de dados TOXLINE, PUBMED e SCOPUS por artigos originais publicados de 1983 a 2015. Do total de 273 artigos elegíveis, foram selecionados 73. Os resultados dos estudos in vitro e in vivo evidenciaram danos genéticos e cromossômicos provocados pelo malathion; os estudos epidemiológicos evidenciaram associações significativamente positivas para cânceres de tireóide, de mama, e ovariano em mulheres na menopausa. Estas evidências do efeito carcinogênico do malathion devem ser considerados diante de sua utilização em programas de controle de arboviroses.

Abstract Malathion has been widely used worldwide in arbovirus control programs. In 2015, it was classified by the International Agency for Research on Cancer (IARC) as a probable carcinogen to humans. This work aimed to systematize the evidence of the carcinogenic and mutagenic effects associated with the exposure of malathion and its analogs, malaoxon and isomalathion. The search was carried out in Toxline, PubMed and Scopus databases for original papers published from 1983 to 2015. In all, 73 papers were selected from a total of 273 eligible papers. The results of in vitro and in vivo studies showed mainly genetic and chromosomal damages caused by malathion. The epidemiological studies evidenced significant positive associations for thyroid, breast, and ovarian cancers in menopausal women. This evidence of the carcinogenic effect of malathion should be considered before its use in arbovirus control programs.

Determination of insecticides' lethal concentrations and metabolic enzyme levels in Triatoma dimidiata / Determinación de concentraciones letales y niveles de enzimas metabólicas de insecticidas en Triatoma dimidiata

Abstract: Objective: The feasibility of the use of WHO impregnated paper and biochemical assays to determine lethal concentrations (LC50 and LC99) and insecticide metabolic enzyme levels of Triatoma dimidiata. Materials and methods: LC50 and LC99 were calculated with WHO papers impregnated at different concentrations of malathion, propoxur and deltamethrin; the percentage of insensitive acetylcholinesterase (iAChE); and the levels of esterases, glutathione S-transferases, and monooxygenases in laboratory nymphs of the first stage (5 to 7 days), were undertaken using the WHO biochemical assays. Results: Respectively the LC50 and LC99 µg/cm2 obtained for malathion were 43.83 and 114.38, propoxur 4.71 and 19.29, and deltamethrin 5.80 and 40.46. A 30% of the population had an iAChE, and only a few individuals had high P450 and β-eterase levels. Conclusion: Impregnated papers and biochemical tests developed by WHO for other insects, proved to be feasible methods in monitoring insecticide resistance and metabolic enzymes involved in T. dimidiata.

Resumen: Objetivo: La factibilidad de usar los papeles impregnados y ensayos bioquímicos según la OMS para determinar concentraciones letales (CL50 y CL99) y niveles enzimáticos en la resistencia a insecticidas en Triatoma dimidiata. Material y métodos: Se calcularon la CL50 y CL99 con papeles impregnados según la OMS a diferentes concentraciones de malatión, propoxur y deltametrina; el porcentaje de acetilcolinesterasa insensible (iAChE); y los niveles de esterasas, glutatión S-transferasas, y monooxigenasas en ninfas de laboratorio del estadio I (5-7 días) se determinaron usando los ensayos bioquímicos según la OMS. Resultados: Se obtuvieron las CL50 y CL99 µg / cm2 respectivamente para malatión 43.83 y 114.38, propoxur 4.71 y 19.29, y deltametrina 5.80 y 40.46. Un 30% de las chinches tuvo iAChE, y sólo pocos individuos tuvieron niveles superiores de P450 y β-eterasas. Conclusión: Los papeles impregnados y ensayos bioquímicos que describe la OMS para otros insectos demostraron ser métodos factibles para monitorear la resistencia a insecticidas y las enzimas metabólicas involucradas en T. dimidiata.

Avaliação do efeito da seleção de populações de campo de Aedes aegypti Linnaeus (1762) com o inseticida organofosforado malathion / Evaluation of the effect of the selection of field populations of Aedes aegypti Linnaeus (1762) with the organophosphate insecticide malathion

No Brasil, organofosforados (OP) e piretróides (PI) foram usados para o controle de larvas e adultos de A. aegypti, respectivamente, desde 1967 e 2000. O uso frequente destes produtos selecionou populações resistentes do vetor. Optou-se então por usar o OP fosforoditioato malathion no controle dos adultos, composto molecularmente diferente do larvicida OP fosforotionato temephos, empregado há mais de 40 anos no país. Acredita-se que a resistência seja principalmente derivada de fatores metabólicos (enzimas que detoxificam o inseticida) ou de mutações nos sítios-alvo dos inseticidas, no Sistema Nervoso Central. Bioensaios com larvas confirmaram a resistência de várias populações ao OP temephos. Inicialmente, bioensaios com mosquitos adultos demonstraram não haver populações naturais brasileiras de A. aegypti classificadas como resistentes ao malathion (dados Laficave), corroborando a viabilidade de seu uso no controle de adultos. Uma vez que o malathion, ainda hoje, é o único composto não-PI aprovado pela OMS para uso em aplicações espaciais, a antecipação de um potencial evento de resistência nas populações naturais do vetor é relevante para subsidiar a continuidade de seu uso. No estudo foram usados bioensaios para avaliar a resistência das amostras do vetor, além de metodologias clássicas e modernas - como a análise dos índices de expressão gênica (RNA-seq) - para investigação dos mecanismos associados à resistência. Foram detectados níveis de resistência elevados contra PI e o OP temephos nas amostras originais das populações de Aracaju/SE e Crato/CE

O mesmo não ocorreu para diflubenzuron e malathion, mais recentemente usados no controle do vetor em campo. Quando ambas as populações iniciais são comparadas, os mosquitos de Aracaju tenderam a apresentar menores níveis de resistência a PI e OP e, simultaneamente, maior atividade de enzimas detoxificadoras e maiores custos evolutivos. Neste estudo também foi realizada seleção com malathion: houve aumento nos índices de RR (razão de resistência) para malathion em todas as réplicas biológicas das duas populações. Os dados sugerem ainda, a inexistência de resistência cruzada entre temephos e malathion. De fato, a seleção com malathion parece ter impactado negativamente sobre a RR frente ao temephos, e também a PI. Inusitadamente, foram observados, nos ensaios com PI, aumentos marcados no status de resistência dos grupos controle das duas populações, sem correlação com as frequências kdr - estas tenderam, inclusive, a diminuir. A avaliação bioquímica dos mecanismos de resistência revelou a possibilidade de GST ter tido papel importante na resposta frente aos PI nos grupos controle de Aracaju, mas não nos de Crato. Além disso, a análise RNA-seq identificou 374 transcritos (~2,6%) considerados diferencialmente expressos (DE) em Aracaju (classificados em oito clusters), e um total de 143 transcritos (~1%) considerados DE em Crato (divididos em cinco clusters). Foram detectadas, em pelo menos uma das populações avaliadas, alterações em genes potencialmente relacionados com a resistência por redução da penetração do inseticida através da cutícula ­ mecanismo que recebe pouca atenção nas avaliações sobre resistência. A possibilidade de enzimas OBP atuarem como 'apresentadoras de moléculas inseticidas', direcionando sua degradação para enzimas MFO, é discutida, assim como de profenoloxidases agirem na formação da cutícula dos espécimes de Aracaju e Crato. (AU)

Biomonitoring of Toxic Effects of Pesticides in Occupationally Exposed Individuals

BACKGROUND: Workers in pesticide manufacturing industries are constantly exposed to pesticides. Genetic biomonitoring provides an early identification of potential cancer and genetic diseases in exposed populations. The objectives of this biomonitoring study were to assess DNA damage through comet assay in blood samples collected from industry workers and compare these results with those of classical analytical techniques used for complete blood count analysis. METHODS: Samples from controls (n = 20) and exposed workers (n = 38) from an industrial area in Multan, Pakistan, were subjected to various tests. Malathion residues in blood samples were measured by gas chromatography. RESULTS: The exposed workers who were employed in the pesticide manufacturing industry for a longer period (i.e., 13-25 years) had significantly higher DNA tail length (7.04 μm) than the controls (0.94 μm). Workers in the exposed group also had higher white blood cell and red blood cell counts, and lower levels of mean corpuscular hemoglobin (MCH), MCH concentration, and mean corpuscular volume in comparison with normal levels for these parameters. Malathion was not detected in the control group. However, in the exposed group, 72% of whole blood samples had malathion with a mean value of 0.14 mg/L (range 0.01-0.31 mg/L). CONCLUSION: We found a strong correlation (R2 = 0.91) between DNA damage in terms of tail length and malathion concentration in blood. Intensive efforts and trainings are thus required to build awareness about safety practices and to change industrial workers' attitude to prevent harmful environmental and anthropogenic effects.

Serie parasitosis en dermatología: pediculosis / Parasitosis in dermatology: pediculosis

La enfermedad producida por Pediculus humanus capitis, conocida como pediculosis, es una parasitosis específica del ser humano de distribución mundial. El contagio puede ser directo por contacto con el cuero cabelludo de una persona afectada, o por fómites contaminados con parásitos, por lo que no distingue raza, sexo, edad ni nivel socioeconómico. Presentamos el caso de una paciente de 80 años con una forma típica de pediculosis. (AU)

The disease caused by Pediculus humanus capitis, known as pediculosis, is a human specific parasitosis. It has a worldwide distribution. Transmission can be by direct contact with the scalp of an affected person or by contaminated fomites with parasites. This infestation makes no distinction of race, sex, age, or socioeconomic status. We present a case of an 80 years old patient with a typical case of pediculosis. (AU)

Effects of malathion on testicular spermatogenic function in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of malathion on the testicular spermatogenic function of male rats and its working mechanism.</p><p><b>METHODS</b>Forty specific pathogen-free male Wistar rats were randomly and equally divided into four groups: three exposure groups and a control group. Malathion was administered orally to male rats in the exposure groups at 33.75, 54, and 108 mg/kg (1/32 LD₅₀, 1/20 LD₅₀, and 1/10 LD₅₀) for 60 days. Rats in the control group received an equal volume of water. The body weights of rats were measured after exposure. The organ weights and coefficients of the testes and epididymes were determined as soon as rats were sacrificed. The sperm motility, counts, and malformation rates were measured in the left epididymis. Histopathological changes, cell apoptosis, and the expression levels of Bcl-2/Bax in the testes of rats were observed using HE staining, terminal deoxynucleotidyl transferase-mediated dUPT-biotin nick end labeling, and immunohistochemistry SABC method.</p><p><b>RESULTS</b>The body weights and the testis weights in the exposure groups were significantly lower than those in the control group (P < 0.01). The exposure groups had significantly lower sperm motility and significantly higher sperm malformation rates than the control group (P < 0.01). The sperm counts were significantly lower in the exposure groups than in the control group (P<0.01). The sperm counts and motility were negatively correlated with exposure dose (r = -0.81, P < 0.01; r = -0.51, P < 0.01), while the sperm malformation rate was positively correlated with exposure dose (r = 0.85, P 0.01). The exposure groups had significantly higher spermatogenic cell apoptosis rates than the control group (P<0.01). The expression level of Bax was significantly higher in the exposure groups than in the control group (P<0.01), while the expression level of Bcl-2 was significantly lower in the exposure groups than in the control group (P < 0.01). Histopathological examination of the testes showed degenerative changes in the seminiferous tubules at various doses along with the increase in malathion exposure dose.</p><p><b>CONCLUSION</b>Malathion affects the testicular spermatogenic function of male rats and its working mechanism may involve cell apoptosis induced by down-regulation of Bcl-2 and up-regulation of Bax.</p>

Avaliação da vestimenta utilizada como equipamento de proteção individual pelos aplicadores de malationa no controle da dengue em São Paulo, Brasil / Evaluation of personal protective equipment used by malathion sprayers in dengue control in São Paulo, Brazil / Evaluación de la vestimenta utilizada como equipo de protección personal por los fumigadores de malathion en el control del dengue en São Paulo, Brasil

O inseticida malationa em calda oleosa é utilizado no controle do Aedes aegypti e a sua aplicação é feita por meio de nebulização. Essa atividade exige o uso de equipamento de proteção individual (EPI) pelos aplicadores. Este trabalho avaliou a capacidade de retenção do inseticida malationa nas vestimentas do EPI após nebulização em campo. Foram acompanhadas nebulizações em campo, realizadas pelos agentes de zoonoses, na cidade de São Paulo, Brasil. Antes de cada nebulização eram colocados absorventes sob e sobre a vestimenta do EPI no tórax, na face superior da parede torácica (costas) e nos antebraços. Após cada aplicação, os absorventes eram retirados, identificados e submetidos à extração sob agitação mecânica. Os extratos foram analisados por cromatografia a gás com detector de ionização de chama. Observou-se a presença de malationa nos absorventes sob as vestimentas do EPI já na primeira aplicação, antes da lavagem. Os resultados indicam que os agentes, nas condições avaliadas, estão expostos ao malationa, mesmo com uso de vestimentas de EPI novos.

Malathion insecticide in vegetable oil is used to control Aedes aegypti and is applied by spraying, which requires the use of personal protective equipment (PPE). The current study assessed the capacity of PPE suits to retain malathion. The study monitored field spraying in São Paulo, Brazil. Before each spraying, feminine sanitary napkins were placed under and upon the PPE suit in the chest, back, and forearms. After spraying, the sanitary napkins were removed, labeled, and submitted to extraction under mechanical agitation. The extracts were analyzed by gas chromatography with a flame ionization detector. Presence of malathion in sanitary napkins under PPE suits was observed after spraying and before washing the suits. The findings indicate that sprayers are exposed to malathion, even when they use new PPE suits.

El insecticida malathion en jarabe aceitoso se utiliza en el control del Aedes aegypti y su aplicación se realiza través de un nebulizador. Esta actividad requiere el uso de un equipo de protección personal (PPE) para los fumigadores. Este estudio evaluó la capacidad de retención del insecticida malathion en la vestimenta del PPE. Se acompañó durante el proceso de nebulización en el campo a los agentes responsables de zoonosis en la ciudad de São Paulo, Brasil. Antes de cada nebulización se colocaron absorbentes debajo y encima de la ropa del PPE en el pecho, en la espalda y antebrazos. Después de cada aplicación, los absorbentes fueron identificados y sometidos a una extracción con agitación mecánica. Los extractos se analizaron por cromatografía de gases con detector de ionización de llama. Se observó la presencia de malathion en los absorbentes internos del PPE de la primera fumigación, antes de ser lavados. Los resultados indican que los agentes, en las condiciones evaluadas, están expuestos al malathion, incluso tras el uso de un PPE nuevo.

Effects of malathion on cellularity and sperm differentiation in testis and epididymis of adult rats / Efectos del malatión en la celularidad y diferenciación de espermatozoides en testículo y epidídimo de ratas adultas

Malathion is an organophosphorous insecticide, used worldwide for pest and disease control; however, it could also affect the reproductive patterns of several species. The aim of this study was to determine the effects of malathion in the cellularity and sperm differentiation in testis and epididymis of rats. Twenty adult male Sprague Dawley rats were divided into a malathion-treated group (n=10, dose of 170 mg/kg via subcutaneous injection for a period of 13 days) and control group (n=10, injected only with normal saline). After treatments, the rats were sacrificed by regulated euthanasia and assessed for sperm count in testis and epididymis and epididymal teratospermia degree. The results showed a significant decrease in body, testicular and epididymal weight in animals treated with malathion. Testicular sperm counts in treated rats exhibited a significant decrease in the number of sperm compared to controls (42.56x106 vs. 95.99x106), as well as in epididymis (77.55x106 vs. 106.54x106). Concerning the degree of teratospermia, a significant increase of abnormal sperm in the epididymis of treated rats versus controls (42.1% vs. 21%, respectively) was observed. We conclude that malathion has a cytotoxic effect in rats, significantly reducing the number of sperm produced by the seminiferous tubules and affecting their quality and number during the process of maturation and capacitation in their transit through the epididymis, thus increasing the level of teratospermia.

El malatión es un insecticida organofosforado, ampliamente usado en el control de plagas y pestes, sin embargo también puede afectar a los patrones reproductivos de las especies. El objetivo de este trabajo fue determinar los efectos de malatión en la celularidad y diferenciación de espermatozoides en testículo y en epidídimo de ratas. Veinte ratas macho adultas de la cepa Sprague Dawley, fueron divididos en grupo tratado con malatión (n=10) en dosis de 170 mg/kg de peso, inyección sub cutánea (s.c.), por un período de 13 días (duración del ciclo del epitelio seminífero) y grupo control (n=10), los cuales solo fueron inyectados con suero fisiológico. Finalizado el tratamiento las ratas fueron sacrificadas por eutanasia normada y se procedió a medir el recuento espermático en testículo y epidídimo y el grado de teratospermia en epidídimo. Los resultados obtenidos muestran una disminución significativa en el peso corporal, testicular y del epidídimo de ratas machos tratados con malatión. El recuento espermático en testículo de ratas tratadas, al compararlos con ratas controles, muestra una disminución significativa en el número de espermatozoides (42,56x106 / 95,99x106), igual comportamiento se observó en epidídimo (77,55 x106 / 106,54 x106). Al determinar el grado de teratospermia se observó un aumento significativo de espermatozoides anormales, en el epidídimo de las ratas tratadas versus los controles (42,1% y 21%, respectivamente). Se concluye que malatión tiene un efecto citotóxico en ratas, disminuyendo significativamente el número de espermatozoides producidos por los túbulos seminíferos y afectando la calidad y el número de ellos durante el proceso de maduración y capacitación, en su tránsito por el epidídimo, aumentando el nivel de teratospermia.

potential protective and therapeutic effects of aloe vera juice on malathion induced hepatotoxicity in rabbits

the potential protective and therapeutic effects of Aloe vera juice against malathion induced hepatotoxicity were evaluated in this study. one hundred twelve young male rabbits were used ; they were allocated into two sets of experiments included rabbits treated for short [7 days] and long [21 days] periods. Animals of the first set [short period of treatment] were divided into eight groups; each consisted of four treated groups and four control groups [each treated group had its own control]. The animals of the first group were orally dosed with Aloe vera juice [0.84 ml/kg b. wt]. Rabbits of the second group were orally dosed with malathion [5 mg/kg b. wt.]. The third group animals were dosed orally with malathion concomitant with Aloe vera juice [this group served as the protective group]. Animals of the fourth group were dosed orally with malathion; for 7 days followed by Aloe vera juice for the same period [this group served as the therapeutic group]. The design of the second set [long period of treatment] was exactly similar to that of the short period experiments [divided into eight groups; four treated and four control groups] except the duration of treatment which extended to 21 days. Animals of the control groups of Aloe vera treated rabbits were dosed with distilled water, and those of malathion treated animals were dosed with the solvent of the insecticide. All the animals were sacrificed, blood samples were collected and the serum was used to determine the levels of hepatic enzyme markers: lactate dehydrogenase [LDH], aspartate aminotransferase [ASAT], alanine aminotransferase [ALAT] and alkaline phosphatase [ALP] as well as the total bilirubin. the results revealed that treatment of rabbits with malathion caused marked increase in the serum activity of LDH, ASAT, ALAT and ALP in treated rabbits. Administration of Aloe vera juice [in the protective and therapeutic groups] was found to be effective in lowering the elevated activities of these enzymes to approximate near normal levels for both the short and long periods of treatment, especially in the activity of LDH, ASAT and ALP. The present results suggested that Aloe vera juice has ameliorative effects against hepatotoxicity produced by malathion in the treated rabbits

possible protective effect of vitamin C on the kidney cortex of adult female albino rat after chronic exposure to malathion: a light and electron microscopic study

Chronic exposure to malathion is still a major medical problem in occupational and environmental settings. The raised issue of the antioxidants effect on different tissues provides a new line of protection against the inevitable exposure to insecticide residues in food or through environmental contamination. The aim of the study was to determine the effects of vitamin C supplementation on renal cortical tissue after chronic exposure to malathion. Thirty female albino rats aged 3 months were divided into three equal groups: group I control adults were fed the basal diet; group II was given commercial malathion dissolved in distilled water orally by intragastric tube at a dose of 100 mg/kg/day for 2 months; and group III was given malathion in the previously described way at the same dose in addition to vitamin C [pure ascorbic acid powder] dissolved in distilled water and given orally by intragastric tube at a dose of 20 mg/100 g/day for 2 months. The specimens were obtained from the kidney and prepared for light and electron microscopic examinations. Morphometric and statistical studies were carried out in the three studied groups. It was observed that treatment with malathion disrupted the normal histological structure of the renal cortex. Thickened glomerular basement membrane was evident. There was widespread vacuolation of tubular lining epithelium and increased heterochromatin clumps in most of the nuclei. The mitochondria appeared disorganized with loss of cristae. The diameter of renal corpuscles and renal tubules increased, whereas tubular epithelium height decreased significantly compared with the control. Moderate improvement in the previous findings was detected on concomitant supplementation of vitamin C. Vitamin C supplementation played a protective role on the renal cortex exposed to chronic malathion toxicity at the subcellular level

Avaliação da dissipação do inseticida malation utilizado em nebulização a ultrabaixo volume no controle da dengue: avaliação ecotoxicológica e de risco ambiental / Evaluation of malathion insecticides dissipation used in ultra-low volume nebulization in dengue control ecotoxicological assessment and environmental risk

A dengue é um dos principais problemas de Saúde Pública da atualidade. É transmitida por mosquitos do gênero Aedes, sendo a espécie Aedes aegypti o vetor responsável pela transmissão no Brasil. O principal alvo de controle da doença é seu vetor, sendo o controle químico amplamente utilizado em todas as regiões atingidas. Como forma de prevenção ou em períodos de epidemia, torna-se necessária a eliminação dos mosquitos adultos, sendo indicada a nebulização a ultrabaixo volume (UBV) a frio do organofosforado malation por meio do uso de equipamentos pulverizadores acoplados a veículos. Este inseticida utilizado pode sofrer desvios durante e após a aplicação a UBV, caracterizando-se como um potencial agente de desequilíbrio ecológico, podendo atingir e gerar efeitos danosos em organismos não alvos aquáticos e terrestres. Este trabalho teve como objetivo desenvolver e validar um método de análise para o malation em cromatografia líquida de alta eficiência e obter recuperação do inseticida em níveis aceitáveis em água e solo, avaliar seu período de dissipação e tempo de meia vida (t1/2) nestas matrizes e classificá-lo quanto à toxicidade aguda e ao risco ambiental de acordo com diferentes autores, para o microcustáceo Daphnia magna, para a minhoca Eisenia foetida, para o peixe mato grosso (Hyphessobrycon eques) e para a macrófita Lemna minor. O método foi considerado adequado para análise do malation. A recuperação obtida para água foi de 97 por cento e para solo, 96 por cento...

Dengue is one of the major public health problems nowadays. It is transmitted by mosquitoes of the genus Aedes, and the Aedes aegypti specie is the vector responsible for transmission in Brazil. The main target to control the disease is its vector, and the chemical control is widely used in all affected regions. As a preventive measure or in epidemic periods, it becomes necessary to eliminate adult mosquitoes, being indicated the ultralow volume nebulization of malathion organophosphate in cold way through the use of sprinklers attached to vehicles. This used insecticide can suffer deviation during and after application ULV, characterizing itself as a potential agent of environmental imbalance, with the possibility of reach and generate harmful effects on aquatic and terrestrial non-target organisms. This work had the objective to develop and validate a method of analysis for malathion in high performance liquid chromatography and obtain recovery of insecticide in acceptable levels in water and soil, evaluate its dissipation period and half-life time in these matrices and classify it on acute toxicity and environmental risk according to different authors, to the microcrustacean Daphnia magna, to the earthworm Eisenia foetida, to the fish Hyphessobrycon eques and to the macrophyte Lemna minor. The method was considered appropriate for analysis of malathion. The obtained recovery for water was 97 per cent and for soil, 96 per cent . Toxic effects resulting from exposure to...

Perfil de suscetibilidade da população de Aedes aegypti (Diptera: Culicidae) da ilha de Santiago, Cabo Verde, a inseticidas / Susceptibility profile of Aedes aegypti from Santiago Island, Cape Verde, to insecticides

Em Cabo Verde, arquipélago situado na Costa Ocidental Africana, os primeiros casos de dengue ocorreram em 2009, com a notificação de mais de 21.000 casos, a maioria desses registrados na Ilha de Santiago. O mosquito Aedes aegypti foi identificado como vetor, e ações para seu controle, usando os inseticidas temephos (larvicida) e a deltametrina (adulticida), têm sido implementadas. Objetiva-se com esse trabalho avaliar o atual status de suscetibilidade a inseticidas e caracterizar os mecanismos de resistência nessa população. Amostras de A. aegypti da ilha de Santiago foram coletadas através de armadilhas de oviposição, para o estabelecimento de uma população a ser analisada. Foram realizados bioensaios do tipo dose diagnóstica, usando garrafas impregnadas com doses únicas dos adulticidas malathion (organofosforado), deltametrina (piretróide) e cipermetrina (piretróide), e bioensaios do tipo dose resposta, usando múltiplas concentrações dos inseticidas temephos (organofosforado), Bacillus thuringiensis sorovariedade israelensis (bactéria entomopatogênica) e diflubenzuron (inibidor de síntese de quitina). Para a investigação dos mecanismos de resistências, foram realizados testes bioquímicos com substratos específicos para quantificar a atividade das enzimas glutationa S-transferases, esterases (alfa, beta e PNPA) e oxidases de função mista, ligadas a detoxificação de xenobióticos, e a taxa de inibição da acetilcolinesterase ligada a insensibilidade do sítio alvo...

Cape Verde, an archipelago located on the West African Coast, recorded the first cases of dengue in 2009 in an epidemic with more than 21,000 reportedcases. The worst affected area was Santiago Island...

potential protective and therapeutic effects of aloe vera juice against malathion induced haematological changes in rabbits

The potential protective and therapeutic effects of Aloe vera juice against malathion induced haematological changes in young rabbits [Oryctolagus cuniculus] were evaluated in this study. Rabbits were allocated into two sets of experiments short [7 days] and long [21 days] periods. Animals of each set were divided into eight groups; four treated groups and each treated group had its own control. The animals of the first group were orally dosed with Aloe vera juice [0.84 ml/kg b. wt.]. Rabbits of the second group were orally dosed with malathion [5 mg/kg b. wt.]. In the third group [the protective group] animals were dosed orally with malathion concomitant with Aloe vera juice. Animals of the fourth group [the therapeutic group] were dosed orally with malathion; for 7 days followed by Aloe vera juice for the same period. All the animals were sacrificed, blood samples were collected and used to determine the levels of hematological indices: red blood cells [RBCs], white blood cells [WBCs], haemoglobin [Hb], haematocrit [Hct], mean corpuscular volume [MCV], mean corpuscular haemoglobin [MCH] and mean corpuscular haemoglobin concentration [MCHC]. Rabbits treated with Aloe vera juice [group 1] showed insignificant change in WBCs count, MCH and MCHC after treatment for both periods. On the other hand, other parameters exhibited significant [RBCs count] and highly significant [Hb and Hct values] change in rabbits treated for the short period. The rabbits of the second group [treated with malathion] exhibited a marked increase in WBCs count, MCV and MCH values, while, the values of RBCs, Haemoglobin and Hct were decreased. The protective group [Group3] showed that the values of all the tested haematological parameters [except MCHC, in both periods of treatment, and WBCs count in the short period of treatment] recorded a significant change in rabbits treated for short [7 days] or long [21 days] periods. A marked recovery in RBCs count and MCH value was observed in rabbits treated for 21 days. Regarding to group 4 [the therapeutic group], it was found that in both terms the rabbits exhibited insignificant changes in the values of all the tested haematological parameters compared to their corresponding controls, except three parameters in which they recorded significant [WBCs count, MCHC] and highly significant [Hct] increase compared to their control values after the long period only. These observations indicated the ability of Aloe vera juice to improve the deleterious effects caused by malathion administration

Relation of breast cancer and malathion aerial spraying in Arica, Chile / Relación entre cáncer mamario y aspersiones aéreas con malatión en Arica, Chile

Breast cancer mortality has been increasing in Arica Chile where it has surpassed the national rates 11 times between 1990 and 2010. The city of Arica was sprayed with the organophosphrous pesticide malathion in order to control the Mediterranean fly 33 years ago. Moreover we have demonstrated that a malathion treatment induces the formation of breast carcinomas in Sprague Dowley female rats. The objective of this work was to find a relationship between malathion aerial spraying and the increased mortality rate due to breast cancer that has been observed in Arica in recent years. We extracted city data bases with all breast cancer cases diagnosed from 1995 to 2005 from the Dr. Juan Noe Crevani Hospital of Arica city and Ernesto Torres Hospital of Iquique. The number of patients was 100 in Arica and 58 in Iquique, nearby city that has never been sprayed with malathion which had a similar population than Arica in those years. The statistical analysis of the characteristics of the sample related to breast cancer risk showed that there is no significant difference between women from Arica and from Iquique. Nevertheless the patients with more times of exposure to malathion were 5.7-times more likely to be diagnosed with breast cancer (OR= 5.7; p<0.02). In addition, metastases were found in 30.5 percent of the malathion-exposed group and only in 16 percent in the group never exposed (p<0.05). This study suggests that the increase in the mortality rate due to breast cancer occurring in Arica has a significant correlation with the exposure to malathion sprayed over the city more than 30 years ago.

La mortalidad por cáncer de mama ha ido aumentando en Arica Chile, donde ha sobrepasado las tasas nacionales 11 veces entre los años 1990 y 2010. La ciudad de Arica recibió aspersiones del pesticida organofosforado malatión, con el fin de controlar la mosca mediterránea, por primera vez hace 33 años. Por otra parte hemos demostrado que un tratamiento con malatión induce la formación de carcinomas mamarios en ratas hembras Sprague Dowley. El objetivo de este trabajo es encontrar una relación entre las aspersiones con malatión y el aumento en la tasa de mortalidad por cáncer de mama que se ha observado en Arica en los últimos años. Se extrajeron de bases de datos, los casos de cáncer mamario diagnosticados entre 1995 y 2005, en los Hospitales Dr. Juan Noé Crevani de Arica y Ernesto Torres de Iquique. El número de pacientes diagnosticados con cáncer de mama fue 100 en Arica y 58 en Iquique, ciudad que nunca fue fumigada con malatión y con una población similar a la de Arica durante esos años. El análisis estadístico de las características de la muestra, en relación a los factores de riesgo de cáncer mamario, mostró que no hay diferencia significativa entre las mujeres de Arica y de Iquique. Sin embargo, las mujeres con mayor tiempo de exposición al malatión fueron 5,7 veces más propensas a ser diagnosticadas con cáncer de mama (OR = 5,7, p <0.02). Además el 30,5 por ciento del grupo expuesto a malatión presentó metástasis y en el grupo no expuesto sólo el 16 por ciento (p <0.05). Este estudio sugiere que el aumento de la tasa de mortalidad por cáncer de mama que se ha producido en Arica tiene una correlación significativa con la exposición al malatión esparcido sobre la ciudad hace más de 30 años.

Malation vs. Aedes aegypti (Linnaeus) (Diptera: Culicidae) de diferentes regiones de Venezuela / Malathion vs. Aedes aegypti (Linnaeus, Diptera: Culicidae) from different regions of Venezuela

En Venezuela, el malation ha sido ampliamente usado en forma continua en programas de control de aedes aegypti. Por tal motivo se realizó un estudio en mosquitos provenientes de zonas urbanas con alta casuística de dengue de los estados: Amazonas, Aragua, Bolívar, Lara, Mérida y Zulia, para determinar el status de susceptibilidad en este vector al malatión, en comparación con la cepa susceptible referencial, Rockefeller (Rock). Se hicieron bioensayos en botellas tratadas con el insecticida malatión evaluando la dosis diagnóstica 100ug/mL en 30 minutos y ensayos bioquímicos en microplacas para determinar mecanismos metabólicos asociados al status frente al insecticida. Los resultados de los bioensayos mostraron que existe susceptibilidad a malatión, lo cual fue confirmado por pruebas bioquímicas. Sin embargo, se encontraron diferencias significativas entre todas las cepas evaluadas con valores de P<0,005 para esterasas alfa (α), esterasas beta (β) y acetilcolinesterasa normal (Ache) y acetilcolinesterasa inhibida (Achei). La prueba de comparación de medias de Bonferroni encontró similitud entre la cepa Rock, mazonas y Lara para esterasas α y β. Se encontró similitud de la cepa Rock con las cepas de Bolívar y Zulia para las pruebas con Ache y Achei. Este estudio concluye que el malatión mostró su potencial de uso en el control del vector del dengue de las localidades evaluadas.

In Venezuela, malathion has been widely used continuously in control programs for Aedes aegypti. Therefore, a study in mosquitoes from urban areas with high dengue casuistry in the states of Amazonas, Aragua, Bolivar, Lara, Merida and Zulia was conducted to determine the status of this vector susceptibility to malathion, compared with the reference susceptible strain, Rockefeller. Bioassays were done on bottles treated with the insecticide malathion, 100ug/mL evaluating the diagnostic doses in 30 minutes and biochemical assays in microplates were performed to determine metabolic mechanisms associated with status against insecticide. The bioassay results showed that there is malathion susceptibility, which was confirmed by biochemical tests. However, significant differences were found among all strains assessed values of P<0.005 for esterases alpha (α), beta esterases (β) and standard acetylcholinesterase (AChe) and inhibited acetylcholinesterase (Achei). The mean comparison test of Bonferroni showed similarity between the strains Rock, Amazon and Lara for esterases α and β. Similarity was found between the strains Rock, Bolivar and Zulia for the Ache and Achei tests. This study concludes that malathion showed its potential use in controlling the dengue vector in the locations evaluated.

[Toxicity evaluation of malathion, carbaryle and glyphosate in common carp fingerlings [Cyprinus carpio, linnaeus, 1758]]

Common carp [Cyprinus carpio] fishes during release into the rivers estuary of the Caspian southern basin are generally exposed to a broad spectrum of agricultural pesticides. The objective of this study was to investigate the effects of three agricultural pesticides including Malathion, Carbaryle and Glyphosate on C. carpio in lethal level by determining LC[50] 96h and sub-lethal levels via cholinesterase [ChE] activity. The median lethal concentration using a standard method which is called OECD No. 203 [1992], was measured. About 300 fingerlings with average weight of 2.0 +/- 0.4 g were randomly selected and were then exposed to each pesticide in three treatments [0.1, 0.2 LC[50] 96h and negative control] in three replications. 5, 10 and 15 days after the test period, sampling from the head and body of fishes was carried out. The ChE activity was assayed with biochemical method described by Ellman. The LC[50] 96h for three glyphosate, malathion and carbaryle pesticides were obtained as 6.75, 1.3 and 12.67 mg/L, respectively. The mean values of ChE for both head and body under control conditions were found 1241.356 and 723.103 mU/min/mg protein, respectively. Therefore, the ChE activity of head was 1.7 times more than the body. During the test period, inhibition activitiy of ChE was significantly observed in the fishes treated by any of three components in comparison with control [p<0.05]. The ChE inhibition potential by carbaryle and glyphosate was lower than malathion as compared with control. The exposure time concentration exhibited a significant effect compared to the fishes treated by the investigated pesticide types. The used pesticide concentrations for non-target species which were ineffective and permissible according to the lethality bioassay test can lead to their enzyme responses and bio-damages