Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / The development of analytical methods for multiresidue determination of pesticides in food is essential for the efficient monitoring of these compounds in products consumed by the population, enabling regulators to obtain faster and reliable results. This study aimed to the development and validation of a method based on techniques modified QuEChERS-citrate and gas chromatography-mass spectrometry (GC/MS) for the multiresidue determination of 45 pesticides in fruits of pineapple. The method was validated by determining the selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision and accuracy, being configured with detection based on electron impact ionization (EI) and selected ion monitoring (SIM). The method was satisfactory selectivity for all target compounds, except chloroneb. Limits of detection ranged from 0.005 mg/kg and 0.05 mg/kg and limits of quantification between 0.015 mg/kg and 0.09 mg/kg. The linearity was adequate for most analytes at a range of concentration of 0.01 to 0.75 mg/kg with correlation coefficients ranged from 0.9593 to 0.9996. Of pineapple samples analyzed, applying the developed method, were detected the pesticides fenpropathrin, pyraclostrobin, ametryn, triflumizole and trifluralin. / O desenvolvimento de mÃtodos analÃticos para a determinaÃÃo multirresÃduos de agrotÃxicos em alimentos à fundamental para o monitoramento eficiente desses compostos nos produtos consumidos pela populaÃÃo, possibilitando aos ÃrgÃos reguladores a obtenÃÃo de resultados mais rÃpidos e confiÃveis. Este trabalho teve como objetivo o desenvolvimento e validaÃÃo de um mÃtodo fundamentado nas tÃcnicas QuEChERS-citrato modificada e cromatografia gasosa acoplada a espectrometria de massas (CG/EM), para a determinaÃÃo multirresÃduo de 45 agrotÃxicos em frutos de abacaxi. O mÃtodo foi validado determinando-se a seletividade, a linearidade, limite de detecÃÃo (LD), limite de quantificaÃÃo (LQ), precisÃo e exatidÃo, sendo configurado com detecÃÃo baseada em ionizaÃÃo por impacto de elÃtrons (IE) e monitoramento de Ãons selecionados (MIS). O mÃtodo apresentou seletividade satisfatÃria para todos os compostos alvo, com exceÃÃo do cloroneb. Os limites de detecÃÃo variaram entre 0,005 mg/kg e 0,05 mg/kg e os limites de quantificaÃÃo entre 0,015 mg/kg e 0,09 mg/kg. A linearidade foi adequada para a maioria dos analitos na faixa de concentraÃÃo de 0,01 a 0,75 mg/kg, com coeficientes de correlaÃÃo variando entre 0,9593 a 0,9996. Das amostras de abacaxi analisadas, aplicando-se o mÃtodo desenvolvido, foram detectados os agrotÃxicos fenpropatrina, piraclostrobina, ametrina, triflumizol e trifluralina.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente trabalho estudou o uso de processo oxidativo avanÃado para a remoÃÃo do agrotÃxico organofosforado clorpirifÃs. Para tanto, sistema de reator em escala laboratorial e escala piloto foram estudados. Na primeira etapa, em escala laboratorial, foram realizados estudos dos parÃmetros temperatura, pH e dosagem do perÃxido de hidrogÃnio, concentraÃÃo do agrotÃxico e efeito inibitÃrio de Ãnions. Os resultados indicaram que uma temperatura de 45 oC propicia melhor remoÃÃo do agrotÃxico usando apenas a radiaÃÃo UV, contudo, para o sistema combinado UV/H2O2, a temperatura nÃo afetou o rendimento do processo. A influÃncia do pH foi estudada para os sistemas H2O2 e UV/H2O2 e foi verificado que o pH nÃo influenciou na eficiÃncia do sistema UV/H2O2, entretanto, em pH 10 ocorreu um melhor rendimento para o sistema H2O2 na remoÃÃo do agrotÃxico. Entre as dosagens de perÃxido de hidrogÃnio estudadas, a de 1,5g/L foi a mais eficiente na remoÃÃo do agrotÃxico. O efeito inibitÃrio dos Ãnions, cloreto, nitrato, sulfato e carbonato nÃo se mostrou efetivo na remoÃÃo do agrotÃxico durante 480 minutos, contudo, o Ãnion bicarbonato provocou em 60 minutos a total conversÃo do clorpirifÃs em um composto desconhecido. A segunda etapa foi realizada no reator de escala piloto e foram estudados trÃs vazÃes, 1,5; 2,0 e 3,0 L/min. As concentraÃÃes residuais do agrotÃxico ao final de 480 minutos de experimento para os trÃs vazÃes foram 0,30; 0,43 e 0,5 mg/L, respectivamente. A remoÃÃo de turbidez e cor foram eficientes para as vazÃes estudadas, em contraste com a remoÃÃo de DQO. / This study investigated to advanced oxidation process (POA) for removal of organophosphorus pesticide chlorpyrifos. Reactor system, in laboratory and pilot scale, have been studied. In the first stage, in laboratory scale, were performed studies of the parameters temperature, pH, dosage of hydrogen peroxide, pesticide concentration and inhibitory effects of anions. The results indicated that a temperature of 45 oC showed a better pesticide removal using only UV radiation, however, for the system UV/H2O2, the temperature did not affect the process. The pH effect was studied for H2O2 and UV/H2O2 systems and was observed that pH did not affect the efficiency of the system UV/H2O2. In addition, at pH 10 a better performance for the system H2O2 on the removal of pesticide was observed. Hydrogen peroxide dosage also was studied, and 1,5g/L dosage was most efficient in the pesticide removal. The inhibitory effect of the anions, such as chloride, nitrate, sulfate and bicarbonate was not significantive in the pesticide removal at a time of 480 minutes. In contrast, presence of carbonate anion at 60 minutes, there was a total transformation of chlorpyrifos in an unknown compound. The second stage was conducted on a pilot scale, and flow rate were studied (1.5; 2.0 and 3.0 L/min). The final concentration of pesticide at 480 minutes, for the three flow, were 0.30; 0.43 and 0.5 mg/L, respectively. The turbidity and color removal was efficient for all flows studied, in contrast with the DQO removal.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A regiÃo do Baixo Jaguaribe- CE consiste em uma das mais importantes Ãreas de fruticultura irrigada do Estado CearÃ. Nos Ãltimos anos tem sido crescente o nÃmero de casos de cÃncer nos municÃpios de Limoeiro do Norte e QuixerÃ, podendo està associado ao uso indiscriminado de agrotÃxicos. A pesquisa teve como objetivo principal estudar a influÃncia do uso de agrotÃxicos na contaminaÃÃo de Ãguas superficiais e subterrÃneas, utilizadas para irrigaÃÃo e consumo humano, situadas nas proximidades do perÃmetro Irrigado Jaguaribe- Apodi. Na primeira etapa, foi feito um levantamento de 37 princÃpios ativos aplicados pelos agricultores nas principais culturas da regiÃo. Na segunda etapa foram utilizados modelos para avaliar o potencial de contaminaÃÃo desses agrotÃxicos em Ãguas superficiais e subterrÃneas, com base em suas propriedades fÃsico-quÃmicas. Foram aplicados mÃtodo de Screening da EPA e Ãndice de GUS, para anÃlise de potencial de contaminaÃÃo em Ãguas subterrÃneas e MÃtodo de GOSS, para Ãguas superficiais. AtravÃs dos resultados, foram identificados os agrotÃxicos utilizados pelos agricultores da regiÃo do Baixo Jaguaribe com maior potencial de contaminaÃÃo, dentre os quais foram selecionados Atrazina, Metil Paration, ClorpirifÃs, Fenitrotion, TriazofÃs, Propiconazole, Difenoconazole e Azoxistrobina para monitoramento das Ãguas. AlÃm disso, os agrotÃxicos Bentazona, Molinato, Pendimentalina e Malation estabelecidos pelas legislaÃÃes, tambÃm foram monitorados. Na terceira etapa foi realizado o desenvolvimento de mÃtodos cromatogrÃficos para anÃlise dos agrotÃxicos selecionados, utilizando SPME/ GC-MS e SPE / HPLC-UV. ExtraÃÃo por SPME foi otimizada atravÃs seleÃÃo da fibra, estudo do efeito do pH, tempo de equilÃbrio e variaÃÃo do volume de amostra. Na quarta etapa foi realizado as coletas das amostras de Ãguas em 15 pontos mais suscetÃveis a contaminaÃÃo, sendo 7 pontos do canal do DIJA e de reservatÃrios, e 8 poÃos. De acordo com os resultados foram detectados os agrotÃxicos propiconazole, difenoconazole, azoxistrobina, clorpirifÃs, metil paration, atrazina e triazofÃs, os quais pertencem a uma variedade de grupos quÃmicos e diferentes tipos de uso. Os agrotÃxicos propiconazole e difenoconazole apresentando os maiores nÃveis de concentraÃÃo detectados (3,84 - 10,14 e 0,33 - 6,93 μg/L, respectivamente). Cerca de 80% das amostras apresentaram nÃveis acima do estabelecido pela comunidade europÃia, no entanto dentro dos padrÃes brasileiros. Apesar do nÃvel de concentraÃÃo dos agrotÃxicos detectados està dentro do consumo diÃrio aceitÃvel em Ãgua, isso nÃo deve ser tomado como uma justificativa para contaminaÃÃo descontrolada dos recursos hÃdricos. Efeitos de toxicidade aguda e crÃnica, causados pelo uso itensivo de agrotÃxico podem ser verificados ao homem e aos organismos do ecossistema. / The region of Baixo Jaguaribe-CE is considered one of the most important areas of irrigated orcharding in Ceara state. In recent years there has been a growing number of cancer cases in the cities of North Limoeiro and Quixerà and may associated with indiscriminate use of pesticides. The research aimed to study the influence of pesticide use in the contamination of surface and groundwater used for irrigation and human consumption, located in the vicinity of irrigation projects in the region of Baixo Jaguaribe. The first step was a survey of 37 active ingredients applied by farmers in major crop in the region. In the second stage models were used to evaluate the potential for contamination of pesticides in surface water and groundwater, based on their physicochemical properties. Screening method of EPA and GUS index were applied for analysis of potential contamination to groundwater and Goss method for surface waters. Through the results, we identified the pesticides used by farmers in the Baixo Jaguaribe with greater potential for contamination, among which were selected atrazine, methyl parathion, chlorpyrifos, fenitrothion, triazophos, propiconazole, difenoconazol and azoxystrobin for water monitoring. In addition, pesticides bentazone, molinate, malathion and pendimentalina established by legislation, were also monitored. The third step was conducted to develop methods for chromatographic analysis of selected pesticides using SPME / GC-MS and SPE / HPLC-UV. SPME procedure was optimized by selection of fiber, studied the effect of pH, equilibrium time and variation of sample volume. The fourth stage was carried to the sampling of water samples in 15 points more susceptible to contamination (7 points Dija canal and reservoirs, and 8 wells) According to the results detected the pesticide propiconazole, difenoconazole, azoxystrobin, chlorpyrifos, methyl parathion, atrazine and triazophos, which belong to a variety of chemical groups and different types of use. Pesticides propiconazole and difenoconazole showed the highest concentration levels detected (3.84 to 10.14 and 0.33 to 6.93 μg/L, respectively). About 80% of the samples had levels above the established by the European community, however within the Brazilian standards. Despite the concentration level of pesticides detected is within the acceptable daily intake of water, this should not be taken as an excuse for uncontrolled contamination of water resources. Effects of acute and chronic toxicity caused by pesticide use can be observed in humans and organisms in the ecosystem.

The thesis presents the evaluation of polysulfone sorbents for solid phase extraction (SPE) and the development of colorimetric probes for pesticides analysis in water. Through electrospraying and electrospinning techniques, different morphologies of sorbents (particles, beaded fibers and bead-free fibers) were fabricated. The sorbents were morphologically characterized by scanning electron microscopy. Adsorption capacities of sorbents were evaluated by conducting recoveries studies for model pesticides; atrazine, chlorpyrifos and DDT using batch and column SPE modes. Better recovery results were achieved by employing the batch mode of fibers, as values ranged from 98 to 105percent. Further sorbent evaluation was conducted using breakthrough experiments and static experiments. The breakthrough studies indicated that 1700 μL was the sample volume that could be percolated with no breakthrough of the analyte that correspond to a concentration of 150 mg/g of sorbent that can be extracted without any loss of analyte. From static studies, quantities of each model compound adsorbed into the fiber at the equilibrium time were evaluated. The adsorbed atrazine was 65, chlorpyrifos 250 and DDT 400 mg/g of sorbent. Kinetic studies suggested retention mechanism following pseudo first and second order model observed by high correlation coefficients (> 0. 96), demonstrating the fiber affinity to retain both polar and non-polar compounds opening a possibility to be used as sorbent for sample preparation of different classes of pesticides in water. For the second part of the study simple strategies for colorimetric sensing based on silver nanoparticles and polivinylpyrrolidone capped nanoparticles were developed, respectively for atrazine and chlorpyrifos detection. The limits of detection of the methods were 3.32 and 0.88 mg/L for atrazine and chlorpyrifos respectively. The applicability of the probe in real samples was demonstrated by the recoveries studies of tap water varying from 94 to 104 percent. The versatility of the probe was demonstrated by affording a simple, rapid and selective detection of atrazine and chlorpyrifos in the presence of other pesticides by direct analysis without employing any sample handling steps. Attempt to incorporate the probes in a solid support was achieved by using nylon 6 as solid support polymer proving to be fast and useful for on-site detection.

The ability of surfactants to form micelles and solubilise hydrophobic substances in aqueous environments has been widely exploited in formulation science. In spite of extensive studies over the past few decades by both experimental and theoretical methods, however, it remains difficult to predict key micellar parameters such as their size, shape and nanostructure which is essential for their successful implementation in the solubilisation of active ingredients. This is partly due to the vast number of surfactants commercially available but, in addition, the fragmentation of the field of surfactant science, over recent years, has made it more difficult to identify general trends and properties of surfactant systems. A further challenge is in characterising systems of heavily mixed surfactants since our knowledge on pure surfactant systems may not allow us to predict the behaviour of these systems. The broad aim of this thesis was to contribute to these aspects of surfactant science. The first part of the thesis reports a systematic study of the surfactant structure-micellar structure relationship of pure alkyl ethoxylate (CmEn) surfactants. This was done by independently varying the lengths of the alkyl chain and ethoxylate group and measuring the micellar structural properties. The next part of the thesis reports the effects of solubilisation of two model pesticides, Cyprodinil and Diuron, on the size, shape and internal structure of these surfactant micelles. These pesticides were chosen because they were structurally representative of different features of those widely used in agrochemicals. The final part of the thesis reports the work on binary surfactant mixtures that rationalise the general structural features of mixed micelles and their impact on pesticide solubilisation. Various experimental techniques were used including small angle neutron scattering (SANS), nuclear magnetic resonance (NMR), nuclear Overhauser effect spectroscopy (NOESY NMR), dynamic light scattering (DLS) and UV spectroscopy. The key findings of the thesis were that the micellar core volumes could be predicted with reasonable accuracy using the hydrophilic-lipophilic balance (HLB) of the surfactants in pure micelles. NOESY results revealed protrusions of the terminal methylene groups into the ethoxylate shell, thus providing evidence for the theoretically predicted phenomenon referred to as the-shell interface. SANS revealed that solubilisation of both pesticides caused micellar growth, with the long axial lengths of the micelles growing much longer. These structural changes were associated with the dehydration of the ethoxylate shells. Although a partitioning experiment predicted that the pesticides would be solubilised in the hydrated ethoxylate micellar shell, NOESY measurements revealed that the solubilisation occurred predominantly in the micellar cores. The discrepancy was caused by alkyl chain-ethoxylate mixing leading to the formation of dehydrated palisade regions that entrapped the pesticides towards the cores. The results from the binary mixed micelles showed some signs of synergistic behaviour but no enhancement of pesticide solubilisation.

The overuse of agrochemicals by arable crop farmers in Guyana is of increasing concern. But the literature reveals a paucity of information concerning the reasons for farmers‟ persistence of this inappropriate practice. No previous study has been conducted using a structured format to reveal the scope or reasons for farmers‟ sustained overuse of these chemicals. This research adopted an original structured-type approach, suitable for unearthing and explaining the reasons for this phenomenon. The study was theoretically and analytically guided by the theory of practices and critical realist theory respectively, to identify the prevalence, intensity and significant factors of farmer‟s pesticide and fertiliser overuse, but more importantly to elucidate reasons for overuse and formulate relevant recommendations. This investigation utilised a mixed methods strategy of complementary quantitative and qualitative techniques; comprising analysis of data from 229 farm unit surveys and 38 farmer and 19 key informant interviews, respectively. Quantitative analysis, conducted via SPSS software using tables and regression, revealed widespread prevalence of both pesticide and fertiliser overuse among farmers. The overuse consisted of high frequencies and concentrations of the chemicals. The study notes the factors which were significantly associated with overuse including farmers‟ age, education level, area cultivated, land tenure status and the „source-type‟ of information they accessed. However, qualitative analysis, utilising a grounded-theory approach with the aid of NVivo software, demonstrated that unlike the suggestions by other studies, the reasons for farmers‟ overuse were not the single factors which showed statistical significance for overuse practices. On the contrary, this study revealed original findings, which indicated that the reasons for farmers‟ overuse practices were embedded within an intricate network of contingent, support and contextual factors. These explained both the instigation and continuance of agrochemical overuse by farmers. Overall the findings emphasise the need for policy redress, especially regarding the mandate and conduct of farmer-training regarding chemical use, and the regulatory enforcement of appropriate agrochemical use. Understanding the reasons for farmers‟ inappropriate practices revealed new insight into the interpretation of these practices; as consequences of policy deficiency instead of farmer delinquency. Thus, the implications provided to address this problem of farmers‟ agrochemical overuse presented a new orientation to the type of suggestions previously suggested in other studies. The proposals indicated by this study for a targeted resolution of overuse in arable farmers of Guyana are more policy-oriented than farmer-targeted, since this study revealed that farmers‟ overuse behaviour is largely a response to policy-influenced support and contextual factors.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-14T13:14:37Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação FXavier FINAL (Biblioteca).pdf: 2342428 bytes, checksum: 365010253a4800691ade31f06bd296e3 (MD5) / Made available in DSpace on 2017-07-14T13:14:37Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação FXavier FINAL (Biblioteca).pdf: 2342428 bytes, checksum: 365010253a4800691ade31f06bd296e3 (MD5) Previous issue date: 2016-03-26 / CAPES / A agricultura moderna dispõe de muitas tecnologias para alcançar grandes produções com elevada produtividade. A cana-de-açúcar se constitui como uma das principais commodity agrícola do Brasil. Diante da problemática dos agrotóxicos no ambiente, objetivou-se estudar o herbicida Imazapic e entender o comportamento da molécula em um ARGISSOLO AMARELO Distrófico (AAd) e um LATOSSOLO VERMELHO AMARELO Distrófico (LVAd), cultivados com cana-de-açúcar da mata Norte do Estado de Pernambuco. Foram realizados ensaios de isotermas de adsorção nas camadas de 020, 20-40 e 40-60 cm. Observou-se que os modelos das isotermas de adsorção que melhor representaram os dados observados foram o ajuste direto de Freundlich e a isoterma Linear, a qual se adequou melhor ao estudo do Imazapic em todas as camadas dos dois solos estudados. A camada de 20-40 cm do LVAd apresentou um desvio de linearidade, com tendência de saturação. O modelo de Langmuir, ajustado na sua forma direta, foi o que melhor se adequou aos dados experimentais para a camada de 0-20 cm do LVAd. O ARGISSOLO AMARELO Distrófico (AAd) e um LATOSSOLO VERMELHO AMARELO Distrófico (LVAd) mostram a presença predominantemente de minerais Cauliníticos nos dois solos estudados, conferindo homogeneidade mineralógica, no entanto, a mineralogia apresentou uma pequena diferença apenas no índice de cristalinidade da Caulinita (Ct). Ambos os solos resultaram em valores distintos de coeficientes de adsorção (Kd, Koc) e elevados índices GUS, conferindo aos dois solos um elevado potencial para a lixiviação do Imazapic, caracterizando-se como fator de risco à contaminação das camadas subsuperficiais. A diferença de adsorção entre os dois solos estudados teve relação direta com os teores de óxidos de Fe, o qual apresentou valores muito maiores no LVAd, resultando em maior interação entre o Imazapic e a fase sólida do solo. / Modern agriculture disposes of many technologies to reach great production with high productivity. The sugar cane constitutes one of the main agricultural commodities of Brazil. In face of the pesticides problem in the environment, it was purposed a study of the herbicide Imazapic to understand the molecule behavior in a Distrophic Yellow Ultisol (AAd) and in a Distrophic Red Yellow Udox (LVAd), cultivated with sugar cane from the North woods of the State of Pernambuco. Adsorption isotherm tests were conducted at 020, 20-40 and 40-60 cm layers. It was observed that the isotherm adsorption models that best represent the examined data were the direct adjustment of Freundlich and the Linear isotherms, which suited better the Imazapic study in all layers of both examined soils. The 20-40 cm layer of the LVAd presented a linearity deviation, with a saturation tendency. Langmuir’s model, adjusted in its direct form, was the one that best adapted to the experimental data for the 0-20 cm layer of the LVAd. The Distrophic Yellow Ultisol (AAd) and the Distrophic Red Yellow Udox (LVAd) reveal a predominant presence of kaolinitic minerals in both soils studied, conferring mineralogical homogeneity, however, the mineralogy presented a slight difference only in the crystallinity of the kaolinite (Ct) ratio. Both soils resulted in distinct values of coefficients of adsorption (Kd, Koc) and elevated levels of GUS, giving both soils a high potential for the leaching of the Imazapic, characterizing it as risk factor to the contamination of the subsurface layers. The different adsorption between the two studied soils had direct relationship with the levels of iron oxides, which presented much higher values in the LVAd, resulting in a higher interaction between the Imazapic and the solid phase of the soil.

Surface-enhanced Raman spectroscopy (SERS) is an emerging and sensitive technique in food analysis providing advantages of rapid detection, simple sample preparation and on-site detection capability over GC and LC methods. Most SERS applications focus on detecting trace amount of analyte in liquid as an alternative approach to HPLC. Herein, we invented an innovative SERS-active needle which is composed with an injection needle and a gold-nanoparticles coated fiber inside the injection needle. The gold nanoparticles-coated fiber was fabricated by reducing gold (III) on a chemically etched stainless wire. The SERS needle can be used to insert into the headspace and liquid sample for simultaneous multiphase sample detection, or a soft tissue like a tomato fruit to detect the analyte inside of the tissue with minimum invasion. Using this needle, we can detect as low as 5 ppb of fonofos in the headspace of water and apple juice samples, compared with the dip method, which cannot detect lower than 10 ppb in water and 50 ppb in apple juice. The SERS needle was also applied in real time pesticide translocation study to monitor internalized thiabendazole in tomato fruit after root uptake. The SERS needle detected thiabendazole inside tomato fruits 30 days after the pesticide exposure in a hydroponic planting environment. Moreover, realizing the advantage of detecting volatile components in the headspace of food sample, we applied the SERS needle in a ground beef spoilage study to detect the spoilage biomarkers in the headspace of the raw beef. As a result, the SERS needle detected volatile spoilage compounds produced by bacteria Lactobacillus. Overall, this invention opens a new field of SERS strategy for broad analytical applications.

This study examines the risk of cancer in children of pesticide applicators from the Agricultural Health Study. The study includes 36,537 children of Iowa participants who were evaluated for cancer incidence during 1975 through 2013 from birth through the age of seventeen. Standard incidence rates for any cancer and specific groups of cancers classified using the International Classification of Childhood Cancer was calculated using rates from the general population of Iowa controlling for year of follow, age, sex, and race. Hazard ratios for Group I-III cancers and paternal exposure to specific pesticides were calculated using exposure information collected on 50 pesticides during phase 1 and 2 of the Agricultural Health Study. The exposure information allowed for calculation of intensity-weighted days of exposure to pesticides using the Agricultural Health Study exposure algorithm. Additionally, maternal ever exposure to specific pesticides was used to evaluate risk of childhood cancer. There were 118 cancers identified in children of Agricultural Health Study participants. The all-cancer standardized incidence ratio was significantly elevated (SIR = 1.27 95% CI: 1.04-1.50). The most common groups of cancers were Group I leukemia, myeloproliferative disease, and myelodysplastic disease (n=34) followed by Group III central nervous system (CNS) and miscellaneous intracranial and intraspinal neoplasms (n=25). For paternal intensity-weighted days of exposure, there were 31 of 50 specific pesticides that had sufficient cases of cancer to investigate using Cox proportional hazard models. The herbicide trifluralin significantly increased the risk for Group I childhood cancers for any parental pesticide exposure 2 years before birth through birth when compared to children with no paternal exposure (HR = 2.72 95% CI: 1.15, 6.44). This was consistent with results found from analyzing exposure split into two quantiles based on median exposure of exposed children with a Group I cancer. Parental use of the herbicide S-Ethyl-dipropylthiocarbamate (EPTC) did not result in a sufficient number of Group III cancer cases to look at levels of exposure to EPTC, but ever exposure showed an increased hazard ratio when compared to children with unexposed fathers (HR = 2.56 95% CI: 1.06, 6.20). Other pesticides (dicamba, cyanazine, and terbufos) showed mixed evidence of an association with specific childhood cancers, but were either under powered to evaluate with sensitivity analysis or showed inconsistent risk across exposure levels. Less extensive exposure information was available for mothers of children of the Agricultural Health Study, so analysis was restricted to ever or never exposure to pesticides during a mother’s lifetime. Additionally, there were a limited number of cases of cancer for which maternal exposure to specific pesticides was reported resulting in only 4 pesticides being evaluated for childhood cancer risk (glyphosate, 2,4-dichlorophenoxyacetic acid (2,4-D), carbaryl, and malathion). For these four pesticides, this study did not detect any increased risk of childhood cancer from maternal exposure. In summary, this study provides the first epidemiological evidence of an increased risk of childhood cancer for trifluralin and EPTC. Since this study provides the first evidence of this increased risk, additional analysis is needed to validate the results. This study demonstrates how pesticide exposure information from participants of the AHS can be used in the evaluation of their children’s cancer risk. Additional follow-up and analysis of this cohort beyond the age of 17 would provide further insight into cancer risk during early adulthood from early life pesticide exposure.

Bacillus-derived larvicides, which selectively target mosquito (Diptera: Nematocera: Culicidae) populations to reduce nuisance and health risks, were applied in the South March Highlands Conservation Forest near residential neighbourhoods in Ottawa, Ontario. The objective was to assess effects of application on the nontarget mosquito relative, Chironomidae (Diptera: Nematocera: Chironomidae), and other nontarget aquatic taxa captured using emergence traps. A secondary objective was to assess physicochemical variables that influence Chironomidae emergence. Study ponds received an application of Bacillus thuringiensis var. israeliensis, a subset also received an application of Bacillus sphaericus, and a group of control ponds were left untreated over 3 years (2016-2018). Weekly sampling included trap collections and measurements of water temperature, pH, water depth, conductivity, dissolved oxygen, ammonia, nitrate, and sulphate. Drought in 2016, high precipitation throughout 2017, and seasonal precipitation in 2018 influenced variable physicochemical conditions. Principal component analyses identified differences between sampling groups and between years. Redundancy analyses correlated insect emergence with pond pH, average water depth and water temperature and indicated a strong relationship between Chironomidae emergence and average water depth. Although significantly less Chironomidae annual emergence was observed at treated sites in 2017 and 2018, zero-inflated negative binomial generalized linear mixed modelling failed to detect a significant Bti treatment effect when controlling for within group variation. Rather, variations in pH, mean water depth and water temperature were identified as drivers of Chironomidae emergence. Culicidae emergence was reduced to zero briefly following treatment in 2017 and 2018. The model detected a marginal negative treatment effect on Culicidae in 2017 only, and a positive treatment effect in 2018 at the onset of a secondary hydroperiod, in the absence of treatment. Variations in pH and water temperature were also identified to be drivers of Culicidae emergence. Modelling failed to detect treatment effects on any of the nontarget taxa abundance, including Diptera, Lepidoptera, Ephemeroptera, Odonata, Coleoptera, Hymenoptera, and Arachnida. An inverse relationship between insectivore and prey taxa abundance was observed. In 2018, taxa richness increased between years and trended higher at treated sites and a positive relationship between insectivore and prey taxa richness was observed. In 2017, Shannon-Weiner index and Simpson’s index of diversity were higher at untreated sites, and in 2018 diversity indices were higher at treated sites, with taxa richness increasing between years and higher evenness trending at treated sites. Our data suggest that treatment effects were potentially shrouded by natural variability of physicochemical variables, especially due to the varying hydroperiod observed over the three years of sampling. Additional work is needed to capture average conditions and separate confounding variables from treatment effects. This study provides an inventory of the current wetland insect community in the South March Highlands Conservation Forest landscape that offers a reference for ongoing mosquito management.