Histopathological and Haematological Effects of Mosquito Coil Smoke on Lungs - An Experimental Study on Albino Rats

Introduction: Mosquito coils are the most preferred anti-mosquito products in many households of Asian countries like India. Short-term exposure to allethrin has been reported to cause toxic effects on respiratory system. Subjects and Methods: Thirty albino rats were divided into five groups (A, B, C, D, and E) of six animals each. Except group A (Control) rest (Group B-E) were exposed to mosquito coil smoke for 4, 6, 8 and 10 weeks respectively. Blood from all the animals was processed to estimate TLC (Total leucocyte count) and results thus attained were analysed using one-way ANOVA test. Rats were sacrificed to procure lung tissue, which was processed by paraffin embedding to obtain haematoxylin and Eosin stained sections. Results: There was significant increase (p value, 0.001) in TLC in all experimental groups compared to control ones. Conclusion: Degenerative changes were obtained in lung tissue of all experimental rats with maximum effect in group Adequate measures should be taken to ensure minimal exposure to coil smoke during domestic use.

Haematological and Histopathological Effects of Mosquito Coil Smoke on Kidney-An Experimental study on Albino Rat

Introduction: Mosquitoes have long been identified as the main vectors of many human and animal diseases like West Nile fever, malaria, dengue, etc. Mosquito coils are the most preferred mosquito repellent products used especially in low-income communities, due to cheap price. The most common active ingredients in mosquito coils pyrethroids, are known to cause nephrotoxicity and,haematoxicity. However substantial data is lacking on the effects of mosquito coils containing d-trans allethrin. Subjects and Methods: In this study we report the histological and haematological effects of smoke from such coil on albino rat (Wistar). The study was performed on Thirty albino rats divided into five groups (A, B, C, D, E) of six animals each. Control group A we left unexposed to coil smoke while rest (B-E) were exposed for 4, 6,8,10 weeks respectively. Results: We observed a statistically significant increase in the levels of serum urea and creatinine in experimental groups C, D and E. Levels of serum sodium and potassium remained unaffected in the experimental animals. Histopathological studies on kidneys revealed generalised degenerative changes proportional to quantity of coil smoke exposure. Conclusion: General human masses should be made aware about such possible hazards and adequate measures should be taken to ensure minimal exposure to coil smoke during domestic use

Toxicological effects of prolonged and intense use of mosquito coil emission in rats and its implications on malaria control / Efectos toxicológicos del uso prolongado e intenso de emisiones de espirales contra mosquitos en ratas y sus implicaciones sobre el control de la malaria

Efectos toxicológicos del uso prolongado e intenso de emisiones de espirales contra mosquitos en ratas y sus implicaciones sobre el control de la malaria. Mosquito coil is a vector control option used to prevent malaria in low income counties, while some studies have addressed this issue, additional reseach is required to increase knowledge on the adverse health effects caused by the prolonged use of coils. In this study we investigated the toxicological effects of fumes from two locally manufactured mosquito coil insecticides (with pyrethroids: transfluthrin and d-allethrin as active ingredients) on male albino rats. For this, we recorded the haematological and biochemical indices, and made histopathology and mutagenicity evaluations in rats exposed to mosquito fumes during 2, 4, 8, 12 and 16 week periods. Haematological determination was performed using automated hematology analyzer to determine White Blood Cell (WBC), Packed Cell Volume (PCV), Red Blood Cell (RBC) and Platelet (PLT) counts, while biochemical evaluations were determined using available commercial kits. Gross histopathological changes were studied for the kidney, liver and lungs in sacrificed rats. The rat sperm head abnormalities assessment was used to evaluate mutagenicity. Mosquito coil fumes produced significant increase (P<0.05) in the levels of total protein, total albumin and bilirubin, when animals were exposed from two weeks to 16 weeks with transfluthrin. Similarly, elevation in the activities of aspartate amino transferase, alanine amino transferase and alanine phosphatase, increased significantly in both insecticides. Increase in WBC, RBC and PCV were recorded for all the exposure periods, however PLT count showed no significant increase (P>0.05). Mutagenicity assessment revealed sperm abnormality was statistically significant (P<0.05) compared with the control at 8, 12 and 16 weeks post exposure to transfluthrin. Histological studies revealed severe lung damage evidenced by interstitial accumulations, pulmonary oedema and emphysema in exposed rats. Intracellular accumulations and severe sinusoidal congestion of liver cells were observed from 12 weeks exposure, indicating liver damage. Our studies indicate that mosquito coil fumes do initiate gradual damage to the host. These pathological effects must be taken into consideration by the malaria control program, particularly when regulating their long term and indoor usage.

Las espirales contra los mosquitos se utilizan en los países de bajos ingresos como una opción para prevenir la malaria controlando el vector de esta enfermedad. A pesar de que algunos estudios han abordado este tema, se requiere más investigación para incrementar el conocimiento sobre los efectos adversos en la salud, causados por el uso prolongado de las espirales. En este estudio se investigaron los efectos toxicológicos de los gases de las espirales a partir de dos insecticidas fabricados en el país (con piretroides: transflutrina y d-aletrina como ingredientes activos) en machos de ratas albinas. Para esto, se registraron los índices hematológicos y bioquímicos, y se hicieron evaluaciones histopatológicas y de mutagenicidad en ratas expuestas a los gases de las espirales durante períodos de 2, 4, 8, 12 y 16 semanas. La determinación hematológica se realizó mediante un analizador de hematología automatizado para determinar el conteo de los Glóbulos Blancos (WBC), el Hematocrito (PCV), Glóbulos Rojos (RBC) y las Plaquetas (PLT), mientras que las evaluaciones bioquímicas se determinaron utilizando kits comerciales disponibles. Los cambios histopatológicos fuertes se estudiaron en el riñón, el hígado y los pulmones de ratas sacrificadas. Las anormalidades en la cabeza de los espermatozoides de las ratas se utilizaron para evaluar la mutagenicidad. El humo de las espirales contra los mosquitos producen un aumento significativo (p<0.05) en los niveles de proteína total, albúmina total y bilirrubina, cuando los animales fueron expuestos de dos semanas a 16 semanas con transflutrina. Del mismo modo, la elevación en las actividades de aspartato amino transferasa, alanina amino transferasa y alanina fosfatasa, aumentó significativamente con ambos insecticidas. Se registro un aumento en los leucocitos, eritrocitos y el hematocrito para todos los períodos de exposición, sin embargo el recuento de las plaquetas no mostró un aumento significativo (p>0.05). Las pruebas de mutagenicidad revelaron que las anormalidades en el esperma de las ratas fue estadísticamente significativa (p>0.05) al comparar el control a las 8, 12 y 16 semanas post exposición a la transflutrina. Los estudios histológicos revelaron una serie de daños pulmonares graves en las ratas expuestas al humo de la espiral, evidenciados por la acumulación intersticial, edema pulmonar y enfisema. Las acumulaciones intracelulares y la congestión sinusoidal severa de las células del hígado se observaron a partir de las 12 semanas de exposición, lo que indica daño hepático. Nuestros estudios indican que los vapores de las espirales contra mosquitos inician el daño gradual al huésped. Estos efectos patológicos deben ser tomados en cuenta por el programa de control de la malaria, particularmente a la hora de regular su uso a largo plazo y bajo techo.

Assessment of anti mosquito measures in households and resistance status of Culex species in urban areas in southern Ghana: implications for the sustainability of ITN use

OBJECTIVE@#To determine resistance status of Culex species to different class of insecticides and assess the major anti-mosquito strategies employed by urban households and their possible effects on malaria acquisition.@*METHODS@#Structured questionnaires were randomly administered to obtain information on demographic characteristics, measures that people use to prevent mosquito bites and their perception of where mosquitoes breed in their communities. Adult susceptibility assays were also carried out using WHO discriminating dosages of four insecticides from different chemical classes against Culex species.@*RESULTS@#Majority of respondents (54.75%) preferred the use of domestic insecticides in the form of aerosols and coils. Among households that used domestic insecticides, the use of coil was most frequent (62.9%) with a mean (95% CI) of 9.18 (8.99, 9.37) coils per week. Strong level of pyrethroid-resistance and multiple insecticide resistance in Culex species were also detected in some of the study sites.@*CONCLUSIONS@#The excessive use of domestic insecticides and high level of resistance in Culex species observed in the study area has implications for the ITN component of the nation's malaria control program in more subtle ways. People will lose interest in the use of ITN when it fails to protect users from bites of resistant Culex species. Excessive use of domestic insecticides may also select resistance in both malaria vectors and Culex species. On this account we recommend that nuisance mosquitoes must be controlled as part of malaria control programs to improve acceptance and utilization of ITN.

Analysis of Pyrethroids in Mosquito Mats, Coils and Spray Canisters.

Use of mosquito mats, coils and spray are popular methods of avoiding mosquito bites. There are many commercially available mosquito mats, coils and spray canisters which contain pyrethroids, that can cause nervous system toxicity on substantial exposure. Prolonged use of these mosquito repellents can affect human health. When cases of pyrethroid poisoning are reported to a forensic toxicologist, it is very important to be able to extract, isolate, separate and detect the pyrethroid compound. Thin Layer Chromatography (TLC) is widely used today for the detection of pyrethroids. More sophisticated techniques such as Gas Chromatography-Mass Spectrometry (GC-MS) or High Pressure Liquid Chro-matography (HPLC) can be used for the confirmation of the compound. It is therefore important to create a laboratory database, which can be helpful in forensic examinations in future.