Several chemical compounds are being studied for their capacities to cause imbalances in several biological systems. Some of those are able to affect the endocrine system and are known as endocrine disruptors. Many negative effects can be induced in the organisms by the action of these chemicals, highlighting the capacity to cause a decrease in the fertility rate, sex inversion, and problems in embryonic development and even cancer in humans. Those contaminants can be found in different environmental conditions, in groundwater, sediments, residual waters, sludges, and even in drinking water. The purpose of this review is to provide a general overview of the main estrogenic endocrine disruptors and their effects on living organisms, showing the most frequently used tools to detect these contaminants in environmental matrices. According to the data found, there is a need to develop more studies and improve the techniques, in order to effectively determine the mechanism of action of these contaminants and, thus, establish appropriate strategies for their removal from the environment and reduce their actions on living beings.

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The study evaluated the effects of brown flaxseed supplementation in natura on the prevention of DNA damage induced by 1,2-dimethylhydrazine (DMH) in vivo. The experimental groups were Negative and Positive Controls and the protocols of Pre-treatment, Simultaneous, Post-treatment, Pre+continuous in relation to the supplementation of brown flaxseed and administration with carcinogenic compound. The results showed that brown flaxseed supplementation does not cause genomic and genetic damage. In addition, brown flaxseed showed a chemopreventive food that reduced the damages assessed by the comet assay up to 94.07x and the damages assessed by the micronucleus assay up to 91.88x. Brown flaxseed supplementation also increased the frequency of monocytes and lymphocytes indicating immunological improvements. Thus, brown flaxseed supplementation is considered safe and reduces the frequency of DNA damage that can lead to tumors. Therefore, if these events are confirmed in humans, flaxseed will have reinforced its indication as a functional chemopreventive food in the prevention of cancer.

Among the bioremediation processes, biostimulation is an effective methodology for the decontamination of organic waste by the addition of agents that stimulate the indigenous microbiota development. Rice hull is a biostimulating agent that promotes the aeration of edaphic systems and stimulates the aerobiotic activity of soil microorganisms. The present study aimed to evaluate the efficacy of the bioremediation and biostimulation processes in reducing the toxicity of sewage sludge (SS) and to evaluate its possible application in agriculture using cytotoxic and genotoxic assays in human hepatoma cells (HepG2). SS of domestic origin was tested as both the pure product (PSS) and mixed with soil (S) and with a stimulating agent, such as rice hull (RH), in different proportions (SS + S and SS + S + RH); we also examined different remediation periods (3 months - T1 and 6 months - T2). For the PSS sample, a significant induction of micronucleus (MN) in T2 was observed with nuclear buds in all of the periods assessed, and we observed the presence of more than one alteration per cell (MN and nuclear bud) in T1 and T2. The PSS sample caused genotoxic effects in the HepG2 cells even after being bioremediated. For the samples containing soil and/or rice hull, no toxic effects were observed in the test system used. Therefore, the addition of SS to agricultural soils should be conducted with caution, and it is important that the SS undergoes a remediation process, such as bioremediation and biostimulation treatments.

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