Orientador: Maria Aparecida Marin-Morales / Resumo: O crescente aumento das atividades antrópicas vem promovendo um aumento nos impactos causados ao meio ambiente. Dentre essas atividades humanas, a mineração, realizada no Brasil desde o século XVII e persistindo até os dias atuais, tem se destacado, quanto à sua potencialidade de causarem danos ambientais. O estado de Minas Gerais é um grande produtor de ouro e nele está localizado o município de Paracatu, onde se encontra a mina Morro do Ouro, que é considerada uma grande lavra a céu aberto, situada a poucos metros do perímetro urbano. Diante deste cenário, o presente estudo tem por objetivo avaliar a biodisponibilidade dos metais presentes nas amostras, as fontes poluidoras envolvidas com a contaminação desses metais e os riscos que esses metais promovem ao meio ambiente, por meio das análises químicas, extrações sequenciais e cálculos de Fator de Enriquecimento (EF), Índice de geoacumulução (Igeo) e Avaliação de Risco (RAC) e o potencial tóxico das amostras, por meio de bioensaios in vivo (Allium cepa e Lactuca sativa) e in vitro (cultura celular humana – HepG2/C3A). Para a avaliação do comprometimento dos rios que recebem influência da mineradora, foram coletadas amostras de água superficiais e de sedimentos de 3 regiões distintas: 1) jusante da mina Morro do Ouro, onde está localizado o município de Paracatu (P1, P2 e P3); 2) jusante da barragem de rejeitos da mina Morro do Ouro (P4, P5 e P6) e 3) rio de captação de água para abastecimento público de Paracatu (P7) e água... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increase of anthropic activities has been promoting an impact increase to the environment. Among these human activities, mining, conducted in Brazil since the XVII century, has stood out for its potential to cause environmental damage. The Morro do Ouro mine, located in Paracatu (state of Minas Gerais, considered a major gold producer) is a large open mining located a few meters from the urban perimeter. According to this scenario, the present study aims to evaluate the bioavailability of the metals present in the samples, the polluting sources involved with the contamination of these metals and the risks that these metals promote to the environment by chemical analysis, sequential extractions and calculations of Enrichment Factor (EF), Geoaccumulation Index (Igeo) and Risk Assessment (RAC) and the toxic potential of samples by in vivo (Allium cepa and Lactuca sativa) and in vitro bioassays (human cell culture - HepG2 / C3A).To evaluate the impact of rivers that receive influence from the mining company, surface water and sediment samples were collected from 3 different regions: 1) downstream of the Morro do Ouro mine, located in Paracatu (P1, P2 and P3); 2) downstream of the Morro do Ouro tailings dam (P4, P5 and P6) and 3) Paracatu water supply river (P7) and water supply provided by Paracatu WTS (Water Treatment Station) (P8). Afterwards, two extracts of eachcollected sediments (solubilized and leached) were prepared. The results demonstrated that this region is highly... (Complete abstract click electronic access below) / Doutor

Mutageniciteten för olika ämnen bestäms vanligtvis med hjälp av konventionella in vivo och in vitro metoder. Att övergå till in silico metoder vore både etiskt och miljö- mässigt gynnsamt. Flera olika parametrar kan användas för att förutse mutagenicitet. Bland dessa ingår energin för lägsta oockuperade molekylorbitalen (LUMO), aktiveringsenergin, lokala min/max i elektrostatiska potentialen (Vs,min/Vs,max), lokala min i ”electron attachment energy” (Es,min ), med flera. Aktiveringsenergin är en parameter som kan förutspå mutagenicitet med hög noggrannhet, förutsatt att reaktionsmekanismen antingen är känd eller kan antas. Däremot är beräkningskostnaden för aktiveringsenergin hög. Mutagen-X (MX) och dess analoger (föreningar med samma grundstruktur men olika funktionella grupper, totalt 29 olika föreningar), är föreningar vars mutagenicitet har bestämts med hjälp av traditionella metoder men har nyligen också kunnat bestämmas genom kvantkemiskmodellering. Kvantkemiskmodellering har med framgång implementerats i studien av Kari Tuppurainen [1]; där LUMO har bestämts för MX och dess analogier. Utöver detta visades även en statistiskt signifikant korrelation mellan LUMO för MX och dess analoger och den biologiska aktiviteten som bestämdes med hjälp av Ames test. Målet med detta arbete har varit att undersöka vare sig mutageniciteten för MX och dess analogier kan även bestämmas genom att beräkna Es,min, Vs,max och aktiveringsenergin. Reaktionen som undersöktes var en Michael additionsreaktion  mellan amingruppen på kvävebasen guanin och betapositionen på MX och dess analogier. Av den anledningen utvärderades parametrarna (Es,min, Vs,max och aktiveringsenergin) vid betapositionen. De beräknade värdena för Es,min var korrelerade med biologiska aktiviteten. Även aktiveringsenergierna för MX och dess analogier beräknades vid betapositionen och korrelerades sedan med biologiska aktiviteten och Es,min värdena. Om en statistiskt signifikant korrelation observerades mellan aktiveringsenergin och Es,min värdena, hade detta varit en indikation att Es,min värden kan användas för att ersätta aktiveringsenergin. Es,min värden har en jämförelsevis låg beräkningskostnad. Dock observerades ingen statistiskt signifikant korrelation mellan Es,min värdena och biologiska aktiviteten. Vidare observerades ingen statistiskt signifikant korrelation mellan aktiveringsenergin och biologiska aktiviteten och/eller Es,min värdena. Därmed fanns flera indikationer att den tänkta reaktionsmekanismen var felaktig. Under efterforskningen hittades en studie som visade att en-elektronreduktionsmekanismen var den mest troliga reaktionsmekanismen för den undersökta reaktionen. Detta kan vara en förklaring till varför en statistiskt signifikant korrelation kunde observeras mellan LUMO och biologiska aktiviteten, medan ingen korrelation observerades för Es,min, Vs,max och aktiveringsenergin mot biologiska aktiviteten. Avsaknaden av en korrelation för dessa parametrar anses bero på att den föreslagna reaktionsmekanismen var felaktig. Vidare studier hade behövts för att undersöka dessa parametrars förmåga att kunna förutse mutagenicitet. / Mutagenicity of various compounds is traditionally predicted by conventional in vivo and in vitro methods. However, transitioning to in silico methods would be beneficial both ethically and environmentally. The descriptors that can be used to predict mutagenicity are the lowest unoccupied molecular orbital (LUMO) energy, activation energy, the local minimum / maximum electrostatic potential energy (Vs,min/Vs,max), the minimum local electron attachment energy (Es,min), etc. The activation energy is a descriptor that can predict mutagenicity accurately provided that the reaction mechanism is known or can be assumed. However, determining the activation energy is computationally costly. Mutagen-X (MX) and its analogues (compounds with the same backbone but different functional groups, 29 compounds in total), are compounds of which the mutagenicity had been characterized by traditional means but recently also using an in silico method – molecular modeling. Molecular modeling had been successively employed in the study by Kari Tuppurainen [Source]; the LUMO of MX and its analogues had been computed and, importantly, the obtained values demonstrated a statistically significant correlation with the biological activity determined using Ames test. The aim of this thesis was to investigate whether the mutagenicity of MX and its analogues could also be determined by computing Es,min, Vs,max and the activation energy. The studied reaction was a Michael addition reaction between an amine group on the guanine nucleobase and the beta position of MX and its analogues. Therefore, the studied parameters (Es,min, Vs,max and the activation energy) were evaluated at the beta position. The computed Es,min values were correlated with the biological activity. Activation energies for MX and its analogues were also computed at the beta position and then correlated with the biological activity and Es,min values.  If a highly statistically significant correlation between the activation energy and Es,min values at the beta position would have been observed, that would indicate that Es,min values  could be used as a substitute for the activation energy. Es,min values have comparatively low computational cost. However, no statistically significant correlation between Es,min values and the biological activity was observed. Furthermore, no statistically significant correlation was observed between the activation energy and biological activity and/or Es,min values, respectively. Thus, there were several indications that the proposed reaction mechanism was incorrect. After consulting literature, we learned that the one electron reduction mechanism would be a more probable reaction mechanism. This could be an explanation as to why a highly statistically significant correlation could be observed for LUMO vs. the biological activity, whereas no correlation was observed for Es,min, Vs,max, the activation energy versus the biological activity. The absence of a correlation for these parameters is thought to be due to the proposed reaction mechanism being inaccurate. Additional studies would have to be performed to further investigate the predictive abilities for mutagenicity of the studied parameters.

No description available.

Polycyclic (or polynuclear) aromatic hydrocarbons (PAHs) are environmental pollutants produced during the incomplete combustion of organic matter. Since many of these compounds have been shown to be mutagenic and/or carcinogenic, an investigation was initiated into determining the PAH content and mutagenicity of the ash that remains after sugar cane crop burning, and the soot deposited on toll booths by vehicle exhaust emissions. Due to the large amount of sugar cane farming in the Natal coastal region and that the favoured method of disposing unwanted leafy trash is crop burning, concern was expressed as to the nature of the residue that is formed. PAHs have been identified in the residues from combusted wood and straw and, due to their intrinsic similarity to sugar cane, it was considered that the burning of sugar cane could generate PAHs. It is well documented that vehicle exhaust emissions exhibit mutagenic properties and PAHs have been identified as the major contributors of this observed mutagenicity. Since a toll plaza is an area of high traffic density, it was considered to be an ideal location for an investigation into the build-up of particles emitted by the passing vehicles, and to study to what extent the operators are exposed to harmful compounds. In addition, this sample acted as a control, since the detection of PAHs and mutagenic activity in the soot would be an indication that the correct experimental techniques were being employed. Samples were collected on site. The sugar cane ash was collected off a field immediately after burning had taken place, and the soot was collected either by scraping the toll booth walls and surrounding areas or by wiping the surfaces with cotton wool swabs. The organic portion of the samples was separated from the inorganic and carbonaceous substances by extraction into a suitable solvent; the use of both acetone and dichloromethane was investigated. The extracts were divided into two portions - one was used for the analysis of PAHs and the other for determining mutagenic activity. Analysis for PAHs involved subjecting the extracts to a sample clean-up routine and the use of a number of analytical techniques to characterise the components. The mutagenic properties of the samples were investigated by means of two bacterial mutagenicity tests: the Salmonella typhimurium assay (the Ames test) and a new commercially available test kit, the SOS Chromotest. A number of PARs were identified in the extracts by means of reverse phase high performance liquid chromatography (HPLC) with both ultraviolet and fluorescence detection, the latter being the more sensitive method. Mutagenic activity was detected for both samples in the Ames test and for the toll booth soot in the SOS Chromotest, and this observed mutagenicity was attributed to the presence of the PAHs. / Thesis (M.Sc.)-University of Natal, Durban, 1992.

Os corantes são amplamente utilizados nas indústrias têxteis, farmacêuticas, alimentícias, cosméticas, fotográficas, entre outras. Contudo, essas substâncias podem ser tóxicas, mutagênicas e resistentes a muitos processos de degradação utilizados em estações de tratamento. Estima-se que cerca de 15% dos corantes utilizados no mundo sejam perdidos durante o processo de tingimento e lançados no ambiente, atingindo principalmente os corpos d\'água. No entanto, apesar da grande quantidade de corantes comerciais disponíveis e da alta quantidade lançada no ecossistema aquático, os estudos sobre a toxicidade dessas substâncias são escassos e pouco se conhece sobre seus efeitos mutagênicos e principalmente ecotoxicológicos. Dentro deste contexto, o objetivo do trabalho foi avaliar a ecotoxicidade, bem como a capacidade dos corantes têxteis Reactive Blue 4 (RB 4) e Reactive Blue 15 (RB 15) de lesar o material genético, empregando ensaios de toxicidade aguda com Daphnia similis e Vibrio fischeri, toxicidade crônica com Ceriodaphnia dubia, genotoxicidade (Teste do Cometa) com fibroblastos de derme humana e mutagenicidade com Salmonella typhimurium. Adicionalmente, avaliou-se a concentração de cobre em Ceriodaphnia dubia expostas ao corante Reactive Blue 15, que possui esse metal na sua estrutura química. O corante RB 4 foi moderadamente tóxico e o corante RB 15 foi relativamente não tóxico para Daphnia similis. Ambos corantes reduziram a luminescência de Vibrio fischeri em elevadas concentrações, sendo o corante RB 4 mais tóxico para a bactéria quando comparado ao corante RB 15. O corante RB 4 induziu efeito hormesis nos ensaios com C. dubia, ou seja, houve um estímulo na reprodução nas menores concentrações, seguido por um decréscimo em concentrações mais elevadas, ao passo que, o corante RB 15 reduziu a fecundidade de C. dubia. Não houve acúmulo de cobre nos organismos expostos ao corante RB 15. Nenhum dos corantes foram genotóxicos para fibroblastos de derme humana e apenas o corante RB 4 induziu mutagenicidade, por substituição de pares de base. Os resultados obtidos mostram que os corantes podem causar efeitos adversos nos organismos mesmo em baixas concentrações e que o lançamento contínuo dessas substâncias nos corpos d\'água é preocupante. / Dyes are widely used in different types of industries, such as textile, pharmaceutical, food, cosmetics, photographic, among others. However, these substances can be toxic, mutagenic and resistant to many degradation processes used in wastewater treatment. It is estimated that about 15% of the dyes used in the world is lost during the dyeing process and released into the environment, affecting mainly water bodies. However, despite the large amount of commercial dyes available and high quantity released in the aquatic ecosystem, studies on the toxicity of these substances are scarce and little is known about their mutagenic and ecotoxicological effects. Considering that, the aim of this study was to evaluate the ecotoxicity, and the ability of the Reactive Blue 4 (RB 4) and Reactive Blue 15 (RB 15) textile dyes to damage the genetic material, using acute toxicity tests with Daphnia similis and Vibrio fischeri, Ceriodaphnia dubia chronic toxicity, genotoxicity (Comet assay) in human dermal fibroblasts and mutagenicity with Salmonella typhimurium. Additionally, we assessed the concentration of copper in Ceriodaphnia dubia exposed to the Reactive Blue 15 dye, which has this metal in its chemical structure. The RB 4 dye was moderately toxic and RB 15 dye was relatively non-toxic to Daphnia similis. Both dyes reduced the Vibrio fischeri luminescence in high concentrations, and the RB 4 was more toxic to bacteria when compared to dye RB 15. The RB 4 dye induced hormesis effect in the C. dubia tests. We observed that the reproduction was stimulated at lower concentrations followed by a decrease at higher concentrations. While the RB 15 dye reduced fecundity of Ceriodaphnia dubia. There was no accumulation of copper in organisms exposed to the RB 15 dye. None of the dyes were genotoxic to human dermal fibroblasts, and only the RB 4 dye induced mutagenicity, by base-pair substitution. The results show that the dyes can cause adverse effects on organisms even at low concentrations and that the continuous release of these substances in water bodies is worrying.

Compostos mutagênicos/genotóxicos podem não ser removidos durante os processos convencionais de tratamento de água para consumo humano e podem provocar mutações em células somáticas e/ou germinativas, o que pode trazer agravos à saúde humana. O objetivo deste trabalho foi avaliar a atividade genotóxica em águas brutas coletadas em seis locais (Itatiba, Valinhos, Sumaré, Indaiatuba, Jundiaí e Artur Nogueira) onde ocorre captação para abastecimento público, na bacia dos rios Piracicaba, Capivari e Jundiaí (Estado de São Paulo), que não têm sua mutagenicidade caracterizada. Foi empregado o teste de Salmonella/microssoma, combinado a processos de extração orgânica (resina XAD), com as linhagens TA98, TA100 e YG1042. A linhagem YG1041 teve seu uso avaliado no monitoramento de águas superficiais. Foram avaliados também diferentes critérios de positividade para o teste e emprego de diferentes doses máximas testadas. Quatro captações avaliadas apresentaram resultados negativos enquanto as captações de Sumaré e Valinhos apresentaram atividade mutagênica. O ribeirão Jacaré foi identificado como uma das fontes da mutagenicidade impactando na captação de Valinhos. A potência máxima detectada, na captação de Sumaré, atingiu 1020 rev/L para a linhagem TA98 na ausência de ativação metabólica e 2600 rev/L para a TA100 com ativação metabólica, potências consideradas moderada e alta, respectivamente. Estes resultados levaram à inclusão do teste de Salmonella/microssoma no monitoramento realizado pela CETESB nas captações de Valinhos e Sumaré a partir de 2006. / Mutagenic/genotoxic compounds may persist after conventional treatment for drinking water production and may induce mutations on somatic or germinative cells which can lead to human health damage. The objetive of this study was to evaluate the genotoxic activity in surface water samples at 6 sites (Itatiba, Valinhos, Sumaré, Indaiatuba, Jundiaí and Artur Nogueira) located at Piracicaba, Capivari and Jundiaí river systems (São Paulo state). These sites are used as source for drinking water and were not previously screened for mutagenic activity. The organic extract (XAD resin) was tested for mutagenicity with the Salmonella assay using TA98, TA100 and YG1042 strains and YG1041 strain had its use in surface water evaluated. Different criteria for analyzing Salmonella/microsoma assay data were also evaluated as well as the use of different highest doses. Four evaluated sites elicited negative results while Sumaré and Valinhos samples presented mutagenic activity. Jacaré river was identififed as one of the mutagenic sources with impact on Valinhos drinking water source. Maximum mutagenic potency, detected at Sumaré water source, were 1020 rev/L for TA98 in the absence of S9 mix and 2600 rev/L for TA100 in the presence of S9 mix. These potency values are classified as moderate and high, respectively. These results lead to the inclusion of the Salmonella/microsoma assay into the monitoring program performed by CETESB (São Paulo State Environmental Protection Agency) at Valinhos and Sumaré from 2006 on.

Os efeitos clastogênicos de campos magnéticos de freqüência extremamente baixa (ELF) foram investigados usando o bioensaio Tradescantia pallida (Trad-MCN). Inflorescências expostas durante 8 horas a doses de ELF-416mG, 833mG, e 4160mG, prescritas para exposição do público e ocupacional, apresentaram freqüência de micronúcleos aumentada no grupo que recebeu a maior dose (10.32±7.31), comparado com os demais (p=0.00, Kruskal-Wallis). Foi demonstrado que a exposição à ELF, induz danos ao DNA de Tradecantia. Estes resultados encorajam o uso deste bioensaio para avaliar a utilidade do monitor em estudos de campo, auxiliando na caracterização da função do ELF como causa de neoplasmas / The clastogenic effects of the extremely low frequency magnetic fields (ELF) were investigated using Tradescantia pallida micronucleus assay (Trad-MCN). Inflorescences exposed during 8 hours to doses of ELF-416mG, 833mG, e 4160mG, prescribed for public and occupational exposures, showed increased frequency of micronuclei in the group receiving the highest dose (10.32±7.31), compared with others (p=0.00, Kruskal-Wallis). We demonstrated that an ELF exposure induces DNA damage in Tradescantia. This results encourages the use of this assay to evaluate the usefulness of this monitor in field studies, helping to characterize the role of ELF in causing neoplasm

A rápida oxidação da matéria orgânica dos solos tropicais é mais uma evidência da grande vantagem do uso de biossólidos como condicionadores, capazes de melhorar as características físicas, químicas e biológicas do solo com grandes reflexos na produtividade agrícola. Portanto, o presente projeto objetivou averiguar o potencial genotóxico e cancerígeno dos lotes do Lodo de Estação de Tratamento de Esgoto (LETE) gerado em uma ETE prédefinida na região da bacia hidrográfica Piracicaba, Capivari e Jundiaí (PCJ1). Estes dados poderão fornecer subsídios para a avaliação do risco das populações humanas e o meio ambiente expostas ao LETE. Foram utilizados 140 ratos Wistar machos com 8 semanas de idade, expostos, via ração, a concentrações de 10.000 e 50.000ppm de LETE, durante 6 e 8 semanas, com os iniciadores DEN (N-dietilnitrosamina) e DMH (1,2- dimetilhidrazina), conforme citado nos respectivos protocolos (Figuras 4 e 5). A avaliação toxicológica do lodo de esgoto desenvolvida pelo Núcleo de Avaliação do Impacto Ambiental Sobre a Saúde Humana (TOXICAM), enfocou os parâmetros toxicológicos, como seu potencial genotóxico, pelos testes do cometa e micronúcleo em sangue periférico e medula óssea e carcinogenicidade pelos ensaios de FCA e FHA. Os dois ensaios foram divididos em 4 grupos (FCA- GI=Controle Negativo, GII=Controle Positivo/DMH III=10.000ppmLETE e GIV=50.000ppmLETE); (FHAGI= Controle Negativo, GII=Controle Positivo/DEN, GIII=10.000ppmLETE e GIV=50.000ppmLETE). Entretanto, na 3ª semana foi realizada hepatectomia parcial em todos os animais dos respectivos grupos do ensaio de FHA. No teste do cometa foram utilizados 10 animais como controle positivo (controle interno - MNU-N-metil-N-nitrosourea), e 10 animais como controle negativo nos respectivos ensaios (FCA e FHA). Os testes em questão indicaram que o LETE não promove aumento do número de criptas aberrantes no cólon, número e área de focos de hepatócitos alterados no fígado, lesões no DNA (cometa), e também, não houve aumento de forma significativa a frequência de micronúcleo nas células, conforme as tabelas a seguir: 2.1(G=III e IV); 3.1(G=IV); 4(G=,III e IV); 5(G=III,IV e V); 6(G=III,IV e V); 7(G=IV e V). Em relação ao controle positivo. Estes dados poderão fornecer suporte na avaliação de risco da população humana e o meio ambiente, quando expostos ao lodo de estação de tratamento de esgoto. / Fast oxidation of organic matter on tropical soils is another evidence of the great advantage of using biosolids as conditioners once they are able to improve biological, chemical and physical characteristics of the soil with remarkable consequences on agricultural productivity. Therefore, the present project aimed at verifying genotoxic and carcinogenic potential plots of sludge from sewage treatment plants in a pre-defined watershed region at Piracicaba, Capivari and Jundiaí (PCJ1). These data may provide support to evaluate risks on human populations and the environment exposed to sludge from sewage treatment plants. In the study, 140 Wistar male rats, 8 weekold, were used. They were exposed, via chow, to a 10.000 and 50.000 ppm concentration of sludge from sewage treatment plants during 6 to 8 weeks with DEN initiators (diethylnitrosamine) and DMH (1,2-dimethylhydrazine) as mentioned in protocols (Figures 4 and 5). Toxicological evaluation of LETE developed by Center of Evaluation of Environmental Impact on Human Health (TOXICAM) focused toxicological parameters with its genotoxic potential by comet and micronucleus assays on peripheral blood and bone marrow in Wistar rats and carcinogenicity using ACF and AHF assays. Both assays were divided into 4 groups (ACF- GI=Negative Control, GII=Positive Control/DMH III=10.000ppmLETE and GIV=50.000ppmLETE); (AHF-GI=Negative Control, GII=Positive Positive/DEN, GIII=10.000ppmLETE and GIV=50.000ppmLETE). Therefore, on the 3rd week partial hepatectomy was performed in every animal from AHF assays respective groups. assays and to FCA comet test, using MNU (N-methyl-N-nitrosourea) as positive control. The tests in question indicated that the SS not promote increased number of aberrant crypts in the colon, number and area of foci of altered hepatocytes in the liver, lesions in DNA (comet), and also, significantly increased the frequency of micronucleus in cells, according to the following tables 2.1(G=III and IV); 3.1(G=IV); 4(G=,III and IV); 5(G=III,IV and V); 6(G=III,IV and V); 7(G=IV and V). For the positive control. These data may provide support to evaluate risks on human populations and the environment exposed to sludge from sewage treatment plants.

Made available in DSpace on 2016-03-22T17:26:40Z (GMT). No. of bitstreams: 1 juliana roth.pdf: 240395 bytes, checksum: 9b92834586cbce747f4f0d4faa4c67e9 (MD5) Previous issue date: 2005-06-30 / Patients with renal chronic disease have an increased incidence of cancer. It is well known that long periods of hemodialysis treatment are linked to DNA damage due to the oxidative stress. This genotoxic effect may cause loss of chromosome fragments, or even entire chromosomes, which form micronucleus (MN) after cell division, and can be detected by the micronucleus test. In the present case-control study we evaluated the genotoxic effect of hemodialysis treatment in 20 patients undergoing hemodialysis (HD), and 20 subjected to peritoneal dialysis (DP), matched for sex and age with 40 controls. Genetic damage was assessed by examining the frequency of micronuclei in 2,000 exfoliated buccal cells per individual. Our results revealed that patients undergoing hemodialysis treatment have a significantly higher frequency of micronucleated cells (5.60±5.31 MNC) compared to control subjects (1.50±2.01 MNC, p<0.01). Interestingly, the same was not observed for the peritoneal dialysis patients, who presented no significant differences in MNC (2.85±2.96) frequency compared to control individuals (3.25±3.85). In addition, we evaluated the possible association between creatine levels, smoking, alcoholic intake, age, time of treatment, incomes of the individuals (separately analyzed according to their gender) and the frequency of micronuclei. The results reported here indicate that the period of treatment is the only factor associated with increased MNC frequency among HD patients (Spearman coefficient 0.414, p=0.01). The number of MN cells found in individuals under six years or less of treatment was significantly lower (2.91±2.74 MN) compared to patients under seven or more years of treatment (8.89±5.96 MN, p<0.05). Overall, peritoneal dialysis may be a safer choice of treatment, but further studies need to be performed to investigate the risks and benefits of both treatments. / n

O processo de tratamento da madeira utiliza substâncias que geram compostos perigosos que podem contaminar os compartimentos ambientais. O presente estudo avaliou uma área sob influência da contaminação de solo proveniente das atividades de uma usina de tratamento de madeira desativada. A presença e o efeito de compostos mutagênicos em amostras ambientais foram utilizados como marcadores de exposição associada à avaliação de marcadores genéticos de efeito precoce em humanos, com foco em crianças como grupo sensível. Uma área 1750 m distante da usina, fora do quadrante dispersão preferencial atmosférica e em oposição à drenagem do local, foi utilizada como local de referência para a coleta de amostras e comparação. Extratos orgânicos de água de abastecimento, poeira de sótão e material particulado atmosférico fino (PM2,5) foram avaliados para mutagenicidade por meio do ensaio Salmonella/microssoma. Cobre (Cu), cromo (Cr), arsênio (As) e pentaclorofenol (PCP) foram quantificados em amostras de poeira do sótão. Os 16 Hidrocarbonetos Policíclicos Aromáticos (HPAs) prioritários foram avaliados nos extratos de PM2,5 e poeira do sótão. Crianças residentes no entorno da usina e na área de referência foram avaliadas quanto à presença de micronúcleos em amostras de sangue e mucosa oral, e danos primários no DNA, pelo ensaio cometa em linfócitos de sangue periférico. De acordo com a análise de metais, as residências perto da entrada da usina foram as mais afetadas. PCP foi identificado em amostras de poeira de sótão (0,49 mg/kg) e a concentração total de HPAs nesta matriz variou 0,40-13,31 mg/g, com maior dispersão. Todas as amostras de poeira do sótão em que a concentração total de HPAs estava acima de 2μg/g apresentaram resposta positiva para a atividade mutagênica. A contribuição dos HPAs para a mutagênese na poeira de sótão representou 10%, indicando que outros compostos podem contribuir para o efeito mutagênico. A atividade mutagênica e a concentração de HPAs nas amostras de PM2,5foram, de maneira geral, mais elevadas na área de risco, embora em alguns períodos de amostragem a área de referência atingiu valores semelhantes ou mesmo superiores. O efeito mutagênico e as concentrações de HPAs observados nas amostras de PM2,5 foram semelhantes aos valores encontrados em estudos que avaliaram áreas urbanas e com influência industrial. Extratos orgânicos de água de abastecimento não apresentaram mutagenicidade. As frequências de MN em linfócitos de sangue periférico e de células binucleadas na mucosa oral foram significativamente maiores no grupo de risco. Nos demais biomarcadores avaliados não foram observadas diferenças significativas entre os grupos. O conjunto de resultados indica a necessidade de novas avaliações utilizando grupo de referência menos suscetível às influências da área contaminada. O conjunto de dados coletados neste estudo indica a necessidade de uma avaliação mais cuidadosa dos biomarcadores individualmente e de um grupo de referência menos suscetível a influências da área contaminada. Apesar da ausência de diferenças significativas entre os grupos de risco e de referência em biomarcadores de danos no DNA avaliados em crianças, os resultados observados nas amostras de poeira de sótão e PM2,5 sugerem que a população esteve ou ainda está potencialmente exposta a substâncias capazes de causar efeitos adversos à saúde humana. / The mutagenic activity and the concentration of PAHs in PM2.5 samples were generally higher in the risk area, although in some periods the reference area has reached similar or even higher values. The mutagenic effect and the concentrations of PAHs recorded in the PM2.5 samples were similar to those found in studies that assessed areas of intense urban occupation and industrial influence. Organic extracts from supply water showed no mutagenicity. The MN frequencies in peripheral blood lymphocytes and binucleated cells of the oral mucosa were significantly higher in the risk group. No significant differences between children from the reference and risk area were observed in others genetic biomarkers assessed. The result set indicates the need for further evaluations using reference group less susceptible to the influences of the contaminated area. The set of data collected in this study indicates the need for a more cautious assessment of biomarkers individually, and a reference group less susceptible to influences from the contaminated area is necessary. Despite the absence of significant differences between the risk and reference groups in biomarkers of DNA damage assessed in children, the results in attic and PM2.5 samples suggest that the population was or is still potentially exposed to substances with strong negatives effects on human health.