Publications by authors named "Joaquim Goncalves Machado Neto"

A collaborative approach, involving resources and expertise from several countries, was used to develop a test cell to measure cumulative permeation by a solid-state collection technique. The new technique was developed to measure the permeation of pesticide active ingredients and other chemicals with low vapor pressure that would otherwise be difficult to test via standard techniques. The development process is described and the results from the final chosen test method are reported.

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Protective clothing is used as a barrier against pesticides when working with agricultural sprays. The aim of this study was to evaluate the pesticide penetration, retention, and repellence of the material and seams of a whole-body protective garment used by applicators of pesticides. The efficiency of the material and seams of the whole-body garment were determined for its classification as proposed by ISO 27065 (ISO, 2011).

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Dengue transmitted by mosquitoes of the genus Aedes, species aegypti, is a major public health concern in Brazil. The chemical control of the mosquito larvae has been performed with the larvicide temephos since 1967. However, vector resistance was reported to temephos in several Brazilian states, and the Ministry of Health ordered the replacement of this larvicide by diflubenzuron (DFB), an inhibitor of chitin synthesis.

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The evaluation of the efficiency of whole-body protective clothing against pesticides has already been carried out through field tests and procedures defined by international standards, but there is a need to determine the useful life of these garments to ensure worker safety. The aim of this article is to compare the procedures for evaluating efficiency of two whole-body protective garments, both new and previously used by applicators of herbicides, using a laboratory test with a mannequin and in the field with the operator. The evaluation of the efficiency of protective clothing used both quantitative and qualitative methodologies, leading to a proposal for classification according to efficiency, and determination of the useful life of protective clothing for use against pesticides, based on a quantitative assessment.

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Pharmacochemicals usage in fish farming disease treatment can cause morphological and functional changes in absorption capacity, metabolism and excretion organs. The aim of this research was to evaluate the histopathological biomarkers in the gills, liver, kidney and skin of pacu (P. mesopotamicus), which have been infected with A.

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As in many aquatic environments, pollution is a widespread problem in Southern Brazil. In our previous work, we demonstrated that sublethal contamination with some agrichemicals impairs the capacity of fishes to elevate cortisol levels in response to an additional acute stressor. In earlier experiments, the experimental design did not allow us to conclude where this effect occurs.

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Exposure to agrichemicals can have deleterious effects on fish, such as disruption of the hypothalamus-pituitary-inter-renal axis (HPI) that could impair the ability of fish to respond to stressors. In this study, fingerlings of the teleost jundiá (Rhamdia quelen) were used to investigate the effects of the commonly used agrichemicals on the fish response to stress. Five common agrichemicals were tested: the fungicide - tebuconazole, the insecticide - methyl-parathion, and the herbicides - atrazine, atrazine+simazine, and glyphosate.

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