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Previous issue date: 2011-10-14 / The Brazil is the third largest producer of cashew nuts in the world. Despite the social
and economic importance of the cashew nut, its production is still carried out
artisanally. One of the main problems encountered in the cashew production chain
are the conditions under which the roasting of the nut occurs to obtain the kernel
from the shell. In the present study was conducted a biomonitoring of the genotoxic
and cytotoxicity effects associated with the elements from the cashew nut roasting in
Jo?o C?mara - RN, semi-arid region of Brazil. To assess the genotoxic was used the
bioassay of micronucleus (MN) in Tradescantia pallida. In addition, it was performed
a comparative between the Tradescantia pallida and KU-20 and other biomarkers of
DNA damage, such as the nucleoplasmic bridges (NBP) and nuclear fragments (NF)
were quantified. The levels of particulate matter (PM1.0, PM2.5, PM10) and black
carbon (BC) were also measured and the inorganic chemical composition of the
PM2.5 collected was determined using X-ray fluorescence spectrometry analysis and
the assessment of the cytotoxicity by MTT assay and exclusion method by trypan
blue. . For this purpose, were chosen: the Amarel?o community where the roasting
occurs and the Santa Luzia farm an area without influence of this process. The
mean value of PM2.5 (Jan 2124.2 μg/m3; May 1022.2 μg/m3; Sep 1291.9 μg/m3) and
BC (Jan 363.6 μg/m3; May 70.0 μg/m3; Sep 69.4 μg/m3) as well as the concentration
of the elements Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br and Pb
obtained at Amarel?o was significantly higher than at Santa Luzia farm. The
genotoxicity tests with T. pallida indicated a significant increase in the number of MN,
NBP and NF and it was found a negative correlation between the frequency of these
biomarkers and the rainfall. The concentrations of 200 μg/mL and 400 μg/mL of PM2.5
were cytotoxic to MRC-5 cells. All together, the results indicated genotoxicity and
citotoxicity for the community of Amarel?o, and the high rates of PM2.5 considered a
potential contributor to this effect, mainly by the high presence of transition metals,
especially Fe, Ni, Cu, Cr and Zn, these elements have the potential to cause DNA
damage. Other nuclear alterations, such as the NPBs and NFs may be used as
effective biomarkers of DNA damage in tetrads of Tradescantia pallida. The results of
this study enabled the identification of a serious occupational problem. Accordingly,
preventative measures and better practices should be adopted to improve both the
activity and the quality of life of the population. These measures are of fundamental
importance for the sustainable development of this activity. / O Brasil ? o terceiro maior produtor mundial de castanha de caju e apesar da
import?ncia social e econ?mica, sua produ??o ainda ? realizada de forma artesanal.
Um dos maiores problemas da cadeia produtiva do caju s?o as condi??es nas quais
ocorre a queima artesanal da castanha para se obter a am?ndoa. No presente
estudo foi realizado um biomonitoramento do potencial genot?xico e avalia??o da
citotoxicidade associada aos elementos oriundos da queima artesanal da castanha
de caju no munic?pio de Jo?o C?mara - RN, semi-?rido brasileiro. Para a avalia??o
genot?xica foi utilizado o bioensaio de micron?cleo (MN) em Tradescantia pallida.
Al?m disso, foi realizado um comparativo quanto a sensibilidade da T. pallida frente
ao clone KU-20 e outros biomarcadores de danos no DNA, tais como as pontes
nucleoplasm?ticas (PNP) e fragmentos nucleares (FN) foram quantificados. A
avalia??o citot?xica se deu pelo ensaio MTT e m?todo de exclus?o por tripan blue.
As concentra??es de material particulado (MP1,0, MP2,5, MP10) e black carbon (BC)
foram determinadas e a composi??o inorg?nica do MP2.5 definida pela t?cnica de
fluoresc?ncia de raios-X. Foram definidos dois pontos testes: Comunidade do
Amarel?o (local de queima da castanha de caju) e Fazenda Santa Luzia (sem
influ?ncia da atividade). Os valores m?dios obtidos para o MP2,5 (Jan - 2124,2 μg/m3;
Mai 1022,2 μg/m3; Set 1291,9 μg/m3) e BC (Jan 363,6 μg/m3; Mai 70 μg/m3; Set
69,4 μg/m3), bem como a concentra??o dos elementos Al, Si, P, S, Cl, K, Ca, Ti, Cr,
Mn, Fe, Ni, Cu, Zn, Se, Br e Pb obtidos no Amarel?o foram significativamente
maiores que na Fazenda Sta. Luzia. Os testes de genotoxicidade com T. pallida
indicaram um aumento de 2-7 vezes maior na frequ?ncia de MN para o Amarel?o.
Os outros biomarcadores tamb?m apresentaram sua frequ?ncia aumentada. Al?m
disso, verificou-se uma correla??o negativa entre a freq??ncia de MN, PNP e FN
com a precipita??o pluviom?trica. As concentra??es de 200 μg/mL e 400 μg/mL do
MP2,5 em suspens?o foram citot?xicas para as c?lulas MRC-5. O conjunto dos
resultados indicaram genotoxicidade e citotoxicidade para a comunidade do
Amarel?o, sendo as altas concentra??es de MP2,5 um dos prov?veis contribuintes
para esse efeito, principalmente pela elevada presen?a de metais de transi??o,
sobretudo Fe, Ni, Cu, Cr e Zn, que potencialmente causam les?es no DNA. Outras
altera??es nucleares, como PNP e FN podem ser utilizadas como biomarcadores
efetivos de danos no DNA em t?trades de T. pallida. Os conjunto dos resultados
possibilitaram a identifica??o de um problema ocupacional grave, com s?rios riscos
aos trabalhadores que exercem a atividade. Diante disto, a ado??o de medidas
preventivas e de melhores pr?ticas, s?o de fundamental import?ncia para o
desenvolvimento sustent?vel da atividade e melhoria na qualidade de vida dos
trabalhadores.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12587 |
| Date | 14 October 2011 |
| Creators | Galv?o, Marcos Felipe de Oliveira |
| Contributors | CPF:32398336468, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781004Y8, Lanza, Daniel Carlos Ferreira, CPF:05372896663, http://lattes.cnpq.br/6851351991421755, Bressel, Tatiana Azevedo Bastian, CPF:69800421068, http://lattes.cnpq.br/6481010060472030, Medeiros, S?lvia Regina Batistuzzo de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Bioqu?mica, UFRN, BR, Bioqu?mica; Biologia Molecular |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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