Orientador: Adjair Antonio do Nascimento / Banca: Gilson Pereira de Oliveira / Banca: Júlio Mendes / Resumo: O presente trabalho procurou verificar a possível interferência do pH do diluidor na eficiência de ixodicidas comerciais. Para tanto, utilizou-se amitraz, clorpirifós, cipermetrina, mais um grupo controle, para verificar os possíveis efeitos de soluções tampão com pH 3, 4, 5, 6, 7, 8, 9, 10 e 11, como diluidores dos ixodicidas, sobre as variáveis: peso médio da oviposição (PMO), relação PMOxPT (peso das teleóginas), porcentagem de eclosão (PE), eficiência reprodutiva (ER) e eficácia da calda (EC). Teleóginas de R. (B.) microplus, obtidas de bovinos infestados com cepa de campo, foram submetidas à biocarrapaticidogramas, uma hora e 24 horas após preparo (HAP) das caldas. O pH do diluente pouco influenciou na eficácia do amitraz nos parâmetros avaliados, embora as linhas de tendência dos resultados para ER e EC tenham mostrado menor ação do ixodicida, à medida que o pH do diluidor aumentava, tanto para uma HAP como para 24 HAP. Para o clorpirifós, os resultados obtidos mostraram diferenças significativas no PMO, PMOxPT e PE nos resultados de uma hora. A ER (uma HAP) e EC (24 HAP) foram influenciadas negativamente pelo pH quando este se elevava. As linhas de tendência dos resultados para ER e EC mostraram diminuição da ação à medida que o pH do diluidor aumentava, tanto para uma hora como para 24 horas. A cipermetrina sofreu pouca influência do pH. Entretanto, a linha de tendência dos resultados para EC foi influenciada pela elevação do pH, quando usada 24 HAP. / Abstract: The objective of the present research is to check, with commercial ixodicides, the possible interference of the pH of the thinner. For this amitraz, chlorpyrifos, cypermethrin, plus a control group, was used to verify the possible effects of buffer solutions with pH 3, 4, 5, 6, 7, 8, 9, 10 and 11, as thinners of the ixodicides, on the following: medium weight of egg mass (PMO), relationship PMOxPT (weight of the teleogines), percentage of larvae hatch (PE), estimated reproduction (ER) and % control (EC). Teleogines of R. (B.) microplus, obtained from cattle infested with field's strains have been submitted to the in vitro immersion tests, one hour and 24 hours after the solution has been prepared (HAP). The pH of the thinners made little difference on the amitraz on the parameters assessed and, statistically, did not show any significant differences, although the tendency of the results for ER and EC showed less action of ixodicide, as the pH of the thinner increased, as much for one HAP as for 24 HAP. As for chlorpyrifos, the results obtained, statistically showed significant differences on the PMO, PMOxPT and PE in the results of one hour. The ER (one HAP) and EC (24 HAP), were negatively affected by pH when this was augmented. The tendency of the results for ER and EC showed a diminution from the action, as the pH from the thinner augmented, as much for one HAP as for 24 HAP. The cypermetrin suffered less influence from pH. However, the tendency of the results for EC were affected by the elevation of pH, when used 24 HAP. / Mestre

Chlorpyrifos (CPF) is a popular organophosphorus insecticide that is heavily used in the agriculture industry as a means of pest control. Chlorpyrifos is known for its toxic effect to inhibit the enzyme acetylcholinesterase (ACHE) in humans and is widely used in areas of California where the site of application is close to occupied areas, such that exposures to residents and bystanders can occur due to secondary drift. Secondary drift refers to the volatilization of a pesticide from the surface to which it was applied (e.g. soil or plant foliage) and subsequent off-site movement in ambient air. Secondary drift is different from spray drift, which occurs during and very shortly after application. The goal of this thesis is to evaluate existing measurements of secondary drift from ambient air measurements of CPF available from California’s Air Monitoring Network (AMN), in comparison to predictions using a state-of-the-art dispersion model. Pesticide use data were obtained from the California Department of Pesticide Regulation (CDPR) website and was compiled to form scenarios to be modeled and compared against measurements taken throughout the year. Probability distributions for the measured and predicted CPF concentrations resulted in correlations ranging from 3% to 91% depending on the year and modeled scenario. Overall the model overpredicted air concentrations for the modeled scenarios, providing conservative values for risk assessment purposes.

The purpose of this work was to determine if environmentally-relevant concentrations of chlorpyrifos and copper, two commonly detected chemicals in Western surface waters, can negatively impact the biological health of salmonids. Both compounds are highly neurotoxic to fish, but each with distinct biological target sites and mechanisms of action. We used common biochemical and physiological indicators of toxicity, and correlated these effects with potentially significant behavioral alterations. For chlorpyrifos, the mechanism of toxic action is the inhibition of acetylcholinesterase (AChE) throughout the peripheral and central nervous system. Here, we conducted biochemical assays of AChE activity in brain and muscle tissues after exposing steelhead trout (Oncorhynchus mykiss) and coho salmon (0. kisutch) to chlorpyrifos for 96 hours. We then correlated the AChE inhibition with behavioral impairment in swimming and feeding activities. In juvenile steelhead and coho exposed to 0.6-2.5 ��g/L chlorpyrifos, AChE activity was inhibited between ~10-65%. This biochemical indicator was significantly correlated with changes in behavioral patterns. Spontaneous swimming rates were reduced ~30-80% in the exposed fish, and strikes at food items (brine shrimp) were reduced ~10-70%. For copper and some other neurotoxicants, the olfactory nervous system is a sensitive target site in fish. The highly-developed olfactory system in salmonids is particularly susceptible to toxic insult by dissolved chemicals since receptor neurons are in direct contact with the aquatic environment. Here, we used electrophysiological techniques to record odor-evoked responses from the sensory epithelium and the olfactory bulb as direct measures of olfactory function in juvenile coho salmon. In fish exposed to copper, chlorpyrifos, or esfenvalerate for 7 days, field potentials recorded from the sensory epithelium and the olfactory bulb showed reduced or obscured olfactory responses to two classes of odorants, which activate non-overlapping populations of receptor neurons. To determine if this reduced sensory input can subsequently alter or diminish olfactory-mediated predator avoidance behaviors, paired physiological and behavioral tests were conducted on juvenile coho exposed to copper. In fish exposed to 2-20 ��g/L copper for 3 hours, olfactory sensitivity was reduced by ~50-9O%. When these fish were presented with a predatory alarm cue (conspecific skin extract), fish with reduced olfactory function increasingly failed to exhibit antipredator behavior. In the following experiments, we show that chlorpyrifos and copper can impair the biochemical and physiological biology of salmonids at environmentally-relevant concentrations, and that these sublethal effects can alter potentially important behavioral patterns. / Graduation date: 2004

Le chlorpyrifos (CPF) est un insecticide organophosphoré qui est capable de produire des effets développementaux chez les rongeurs, tels que des perturbations de la mémoire spatiale, des altérations du niveau de lactivité, des modifications du niveau danxiété et de la dépression. Cependant, ces troubles comportementaux persistants ont été décrits à partir de différentes périodes dexposition courtes (4 jours), et à des doses juste sous le seuil de toxicité de ce produit, et ne peuvent donc pas renseigner directement sur le type de perturbations comportementales que pourrait produire une exposition à des doses plus basses de CPF administrées durant une plus grande partie du développement du cerveau. Pour répondre à cette question, nous avons exposé des souris CD1 au CPF (in utero et via le lait ; par lintermédiaire du gavage de la mère ; 5 mg/kg) durant la fin de la gestation et pendant les deux semaines postnatales. Ensuite, des tests comportementaux ont été réalisés avec les animaux adultes. Nous avons également étudié dans les mêmes conditions la phosalone (PHO), un insecticide organophosphoré dont la toxicité est similaire à celle du CPF, mais qui, contrairement à celui-ci, na pas encore donné lieu à des études de toxicité développementale. Nous avons déterminé que le CPF et la PHO sont capables de produire une altération de la mémoire spatiale à long terme (dans un labyrinthe de Lashley), avec un effet plus marqué chez les souris femelles que chez les mâles et pour la PHO. Par contre, seul le CPF altère la mémoire spatiale à court terme des souris mâles (test dalternance spontanée dans un labyrinthe en T). Le CPF et la PHO produisent également une augmentation du niveau danxiété (« elevated plus maze » et « light and dark box ») et donnent des signes de dépression (« forced swimming test ») chez les souris femelles uniquement. Par contre, le CPF et la PHO diminuent lactivité locomotrice spontanée (test dactométrie et vidéotracking) des souris mâles et non des souris femelles. Nous avons ensuite approfondi létude de lanxiété développementale produite dans les mêmes conditions expérimentales mais par différentes doses subtoxiques. Cela nous a permis de préciser quune dose de CPF plus faible, soit 1 mg/kg, produisait une augmentation du niveau danxiété plus importante que 5 mg/kg chez la souris femelle. Nous nous sommes intéressés ensuite à une exposition au CPF directement chez le jeune, afin de déterminer les troubles de lanxiété conséquents à quatre périodes néonatales différentes de 4 jours. Dans ce contexte, 1 mg/kg de CPF durant 4 jours dexposition par voie sous-cutanée suffirait à produire une augmentation du niveau danxiété chez les souris femelles, sauf pour une période dexposition située en fin de la seconde semaine après la naissance. La dose et la période dexposition jouent donc un rôle sur le type deffet produit. Ces expériences confirment également que plusieurs mécanismes daltération du développement sont mis en route par le CPF. Toujours dans le cadre de lanxiété développée chez les souris femelles adultes et liée à une exposition périnatale au CPF en doses subtoxiques (1 mg/kg, via gavage de la mère), lutilisation danxiolytiques spécifiques a révélé que les troubles de lanxiété seraient en relation avec une modification du fonctionnement des récepteurs sérotoninergique 5HT1A. Une des implications de ces résultats est que lexposition au CPF durant le développement du cerveau serait susceptible de produire des troubles comportementaux persistants apparaissant chez ladulte, à partir de doses bien inférieures à celles décrites jusquici dans la littérature. Il en va de même pour la PHO qui pourtant nétait pas encore renseignée comme représentant un danger pour le développement du cerveau des mammifères./Perinatal exposure to apparently subtoxic doses of the organophosphorus insecticide chlorpyrifos (CPF) elicits some form of developmental effects in adult rodents, like alteration of spatial memory, locomotor activity, anxiety and depression disorders. However, these persistent neurobehavioral effects are described in adults exposed during 4 days of perinatal treatment with doses close to the toxicity threshold, and do not indicate the consequences of a prolonged perinatal exposure to lower doses of CPF. Therefore, we orally treated CD1 pregnant and lactating mice with subtoxic doses of CPF (5 mg/kg, daily) during the 4 last days of gestation and the following 2 weeks after delivery and assessed the behaviour of adult offspring. We also studied the phosalone (PHO), another organophosphorus insecticide, which has the same toxicity as CPF but whose developmental toxicity in mammals has not been examined yet. We have found that CPF and PHO produced an alteration of long-term spatial memory (in the Lashley maze). This effect was more pronounced in female mice and in PHO-treated mice. On the other hand, only CPF (and not PHO) produced a decrease in short-term spatial memory of male mice (spontaneous alternation in a transparent T-maze). Both insecticides increased the anxiety level (in the elevated plus maze and in the light and dark box) and induced signs of depression disorder (forced swimming test) in female mice. We showed that CPF and PHO also decreased the level of locomotor activity only in male mice. Then we further studied the anxiety disorder developed by CPF using several different subtoxic doses of CPF. 1 mg/kg CPF daily treated female mice showed greater increase of anxiety level compared to 5 mg/kg. To determine the developmental effects of short exposure to low subtoxic CPF doses on anxiety levels, we directly (subcutaneously) administrated 1 mg/kg (daily) during 4 different postnatal periods of 4 days to CD1 offspring and evaluated their anxiety level once adults. Exposed female mice presented a general increase of anxiety level except when administration occurred during the end of the second postnatal week. The level and the time of the subtoxic exposure to CPF would influence anxiety. We concluded that CPF induced several mechanisms of developmental toxicity. We used specific anxiolytic drugs to show that 5HT1A serotoninergic receptors are one of the mechanisms altered by a long perinatal period of subtoxic CPF exposure that produces an increase of anxiety level in adult female mice. These results imply that exposure to CPF during brain development may represent a risk to produce persistent behavioural troubles, even at doses lower than previously described in the literature. Exposure to PHO for which no developmental effect has been described in mammals, may produce similar behavioural troubles.

Thesis (Ph.D)--Mississippi State University. College of Veterinary Medicine. / Title from title screen. Includes bibliographical references.

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Bitki Koruma Anabilim Dalı, 2008. / Bibliyografya var.

My thesis is devoted to the resistance of pollen beetle (Meligethes aeneus, son. Brassicogethes aeneus Fabricius, 1775) to pesticides in selected localities in southern Moravia. Collecting adults was performed in the spring of 2013 by tapped into polyethylene bags. Adults are collected from the stands of oilseed rape, mustard and poppy. Tests were performed on the basis of the methodology of Insecticide Resistance Action Committee number 011, 021, 025. In total, we tested the pollen population from 18 locations. For testing, we used the following chemical substances: Biscaya 240 OD, cypermethrin, lambda-cyhalothrin, tau-fluvalinate, etofenprox, chlorpyrifos(ethyl). We evaluated 100% of the registered dose of pesticides after 24 hours. From the results of the individual populations, we found large differences in resistance to chemicals.

Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-26Bitstream added on 2014-06-13T20:35:32Z : No. of bitstreams: 1 fernandesgarcia_nl_me_jabo.pdf: 541165 bytes, checksum: c8e23f4d551cb84693238f6efb27a6b3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho procurou verificar a possível interferência do pH do diluidor na eficiência de ixodicidas comerciais. Para tanto, utilizou-se amitraz, clorpirifós, cipermetrina, mais um grupo controle, para verificar os possíveis efeitos de soluções tampão com pH 3, 4, 5, 6, 7, 8, 9, 10 e 11, como diluidores dos ixodicidas, sobre as variáveis: peso médio da oviposição (PMO), relação PMOxPT (peso das teleóginas), porcentagem de eclosão (PE), eficiência reprodutiva (ER) e eficácia da calda (EC). Teleóginas de R. (B.) microplus, obtidas de bovinos infestados com cepa de campo, foram submetidas à biocarrapaticidogramas, uma hora e 24 horas após preparo (HAP) das caldas. O pH do diluente pouco influenciou na eficácia do amitraz nos parâmetros avaliados, embora as linhas de tendência dos resultados para ER e EC tenham mostrado menor ação do ixodicida, à medida que o pH do diluidor aumentava, tanto para uma HAP como para 24 HAP. Para o clorpirifós, os resultados obtidos mostraram diferenças significativas no PMO, PMOxPT e PE nos resultados de uma hora. A ER (uma HAP) e EC (24 HAP) foram influenciadas negativamente pelo pH quando este se elevava. As linhas de tendência dos resultados para ER e EC mostraram diminuição da ação à medida que o pH do diluidor aumentava, tanto para uma hora como para 24 horas. A cipermetrina sofreu pouca influência do pH. Entretanto, a linha de tendência dos resultados para EC foi influenciada pela elevação do pH, quando usada 24 HAP. / The objective of the present research is to check, with commercial ixodicides, the possible interference of the pH of the thinner. For this amitraz, chlorpyrifos, cypermethrin, plus a control group, was used to verify the possible effects of buffer solutions with pH 3, 4, 5, 6, 7, 8, 9, 10 and 11, as thinners of the ixodicides, on the following: medium weight of egg mass (PMO), relationship PMOxPT (weight of the teleogines), percentage of larvae hatch (PE), estimated reproduction (ER) and % control (EC). Teleogines of R. (B.) microplus, obtained from cattle infested with field's strains have been submitted to the in vitro immersion tests, one hour and 24 hours after the solution has been prepared (HAP). The pH of the thinners made little difference on the amitraz on the parameters assessed and, statistically, did not show any significant differences, although the tendency of the results for ER and EC showed less action of ixodicide, as the pH of the thinner increased, as much for one HAP as for 24 HAP. As for chlorpyrifos, the results obtained, statistically showed significant differences on the PMO, PMOxPT and PE in the results of one hour. The ER (one HAP) and EC (24 HAP), were negatively affected by pH when this was augmented. The tendency of the results for ER and EC showed a diminution from the action, as the pH from the thinner augmented, as much for one HAP as for 24 HAP. The cypermetrin suffered less influence from pH. However, the tendency of the results for EC were affected by the elevation of pH, when used 24 HAP.

Made available in DSpace on 2015-03-26T13:23:50Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1329919 bytes, checksum: 6b164935d25452c369af186b5fc11ade (MD5) Previous issue date: 2013-03-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Over the last decades, it has been found high levels of water contamination with substances derived from agricultural areas. In this context, we highlight the organophosphate insecticides, which offer high risk to public drinking, watering livestock and preservation of aquatic flora and fauna. Chlorpyrifos, included in this class, is a widely used insecticide in the world and is among the most used in Brazil. Given the damage caused by these substances when they reach water bodies, plus the difficulty of remediation of these environments, it is essential to know techniques to minimize this process. The constructed wetlands (CWs) are shown as an alternative, and some experiments have demonstrated their ability to remove recalcitrant contaminants such as pesticides. The objective of this research was to evaluate the ability of remediation of water contaminated with the insecticide chlorpyrifos through horizontal subsurface flow constructed wetlands planted with different macrophytes. It was measured the reduction of the chlorpyrifos concentration and the reduction of toxicity over hydraulic retention times of 24, 48, 96, 144 and 192 h. The experiment consisted in four pilot scale CWs: CWC without vegetation; CWT cultivated with Tifton 85 (Cynodon spp.); CWM cultivated with Mentha aquatic and CWE cultivated with dotted knotweed (Polygonum punctatum). The initial concentration of chlorpyrifos applied in all CWs was 1 mg.L-1. Before beginning the treatments, it was applied diluted sewage for biofilm insertion on the systems. For execution of quality ecotoxicological acute tests, it was used the specie Daphnia similis. The analysis of variance showed there was no statistical difference, at the 5% level of probability, in the removal of chlorpyrifos between the studied CWs and over the hydraulic retention times. There was a great efficiency in removing pesticide, with overall average of 98.6%, whereas in the first hydraulic retention time, 24 h, there was removal of chlorpyrifos to below the limit of detection, implying at efficiency greater than 99% for the CWC, CWM, CWE and CWT. This result is mainly attributed to adsorption and microbial degradation. For standard acute toxicity tests with Daphnia similis, in accordance with results from removal efficiency of chlorpyrifos, for most samples there was a reduction in toxicity above 80%. Ecotoxicological tests with effluents of constructed wetland systems studied are a good choice as an indicator of the effectiveness of treatments and a promising alternative to complement the physical and chemical analyzes. / Nas últimas décadas, tem-se constatado alto índice de contaminação dos recursos hídricos com substâncias oriundas de áreas agrícolas. Neste contexto, destacam-se os inseticidas organofosforados, que oferecem elevado risco para abastecimento público, dessedentação de animais e preservação da flora e fauna aquática. O clorpirifós, incluído nesta classe, é um inseticida amplamente utilizado no mundo e está entre os mais utilizados no Brasil. Face aos danos causados por estas substâncias quando alcançam corpos hídricos, somado à dificuldade de remediação destes ambientes, torna-se essencial o conhecimento de técnicas capazes de minimizar tal processo. Os Sistemas Alagados Construídos (SACs) mostram-se como uma alternativa, tendo sido evidenciado em alguns experimentos sua capacidade de remover contaminantes recalcitrantes, como os pesticidas. O objetivo desta pesquisa foi avaliar a capacidade de remediação de água contaminada com o inseticida clorpirifós, por meio de sistemas alagados construídos de escoamento horizontal subsuperficial, em que foram cultivados diferentes macrófitas. Mensurou-se a redução da concentração do clorpirifós bem como a redução da toxicidade nos tempos de retenção hidráulica de 24, 48, 96, 144 e 192 h. O experimento foi composto por quatro SACs construídos em escala piloto: SACC sem vegetação; SACT cultivado com capim tifton 85 (Cynodon spp.); SACM cultivado com Mentha aquatica e SACE cultivado com Erva de bicho (Polygonum punctatum). A concentração inicial de clorpirifós aplicada em todos os SACs foi de 1 mg L-1. Antes do início dos tratamentos, aplicou-se esgoto sanitário diluído para inserção do biofilme no sistema. Para realização do teste ecotoxicológico agudo qualitativo, utilizou-se a espécie Daphnia similis. A análise de variância demonstrou que não houve diferença estatística significativa, em nível de 5% de probabilidade, na remoção do clorpirifós entre os SACs estudados e ao longo dos tempos de retenção hidráulica. Observou-se pelas análises cromatográficas alta eficiência na remoção do inseticida, com média geral de 98,6%, sendo que já no primeiro tempo de retenção hidráulica, 24 h, houve remoção do clorpirifós para valores inferiores ao limite detecção do CG, implicando em uma eficiência maior que 99% para os sistemas SACc, SACM, SACE e SACT. Tal resultado é atribuído principalmente aos processos de adsorção e degradação microbiana. Para os ensaios padronizados qualitativos de toxicidade aguda com Daphnia similis, de forma semelhante aos resultados de eficiência de remoção do clorpirifós, observou-se para a maioria das amostras a redução de toxicidade acima de 80%. Constatou-se que os testes ecotoxicológicos com os efluentes dos sistemas alagados construídos estudados são uma boa opção como indicativo da eficiência dos tratamentos e uma promissora alternativa na complementação de análises físicas e químicas.

Made available in DSpace on 2014-06-11T19:30:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-27Bitstream added on 2014-06-13T21:00:37Z : No. of bitstreams: 1 tofolo_vc_me_rcla.pdf: 520198 bytes, checksum: 81a305ec02da5170d24bfe930d1ea7be (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste trabalho foi procurar conhecer os efeitos de três substâncias químicas, sulfluramida, fipronil e clorpirifós, sobre a espécie de formiga não-alvo Ectatomma brunneum (Hymenoptera: Formicidae: Ectatomminae), respondendo às seguintes questões: as marcas comerciais de iscas formicidas granuladas utilizadas neste trabalho são atrativas a esta espécie de formiga não-alvo ou simplesmente repelentes? Sendo atrativas, qual o comportamento exercido pelas operárias? Elas ingerem as iscas no local ou carregam para o interior do ninho? Há devolução? Em condições de múltipla escolha alimentar, esta atratividade permanece ou ocorre somente na ausência do alimento convencional? No que acarreta o contato direto e indireto das formigas com as iscas? Ocorre mortalidade significativa? Qual dos ingredientes ativos é mais prejudicial? Os produtos são seletivos? Os resultados obtidos através dos testes em laboratório revelaram que, em condições normais de exposição, as operárias de E. brunneum não foram repelidas pelas iscas formicidas. No entanto, não houve atratividade suficiente para induzir o carregamento ou ingestão. Quando esse material foi umedecido, a atratividade aumentou significativamente, permitindo que porções das iscas fossem ingeridas na própria arena de forrageamento ou carregadas para o interior do ninho e distribuídas aos outros indivíduos, não sendo registrada, em nenhum dos tratamentos, a devolução total ou parcial das porções carregadas. Após 48 horas de exposição, os três ingredientes ativos foram tóxicos, de modo que a população foi reduzida em 35,56% no tratamento com clorpirifós, 31,11% com sulfluramida e 30% com fipronil ao final de 20 dias de observação. As iscas à base de fipronil foram mais atrativas que as de sulfluramida e clorpirifós... / This work aimed at contributing to a better knowledge on the effects of three chemical substances, sulfluramid, fipronil and chlorpyrifos, on the non-target species of ant Ectatomma brunneum (Hymenoptera: Formicidae: Ectatomminae), answering the following questions: are the brands of granulated insecticide baits employed in this work attractive to this species of non-target ant or are they just repellent? If attractive, what is the behavior exhibited by the workers? Do they ingest the baits in the spot or take them into the nest? Is there any devolution? Under conditions of multiple food choice, does this attractiveness remain or does it happen only in the lack of the conventional food? What is the outcome of direct or indirect contact between the ants and the baits? Is there significant mortality? Which of the active ingredients is the most harmful? Are the products selective? The results obtained from the tests in laboratory showed that, under conditions of normal exposure, the workers of E. brunneum were not repelled by the insecticide baits. Nevertheless, there was not enough attractiveness as to lead to transporting or ingesting. When the material was moistened, the attractiveness increased significantly, allowing portions of bait to be ingested at the very foraging arena or to be taken into the nest and distributed to the other individuals. Total or partial devolution of the portions carried was not observed in any of the treatments. After a 48 hour exposure the three active ingredients proved to be toxic, for the population was reduced in 35.56% in the treatment with chlorpyrifos, 31.11% with sulfluramid and 30% with fipronil at the end of 20 days of observation. The fipronil based baits were more attractive than the ones based on sulfluramid and chlorpyrifos...(Complete abstract click electronic access below)