The present study is the first assessment of occupational risk associated with artisanal cashew nut roasting using exposure and effect biomarkers, as well as a characterization and dispersion analysis of the released particulate matter... more
The present study is the first assessment of occupational risk associated with artisanal cashew nut roasting using exposure and effect biomarkers, as well as a characterization and dispersion analysis of the released particulate matter (PM). A real-time particle monitor was used to quantify PM1.0, PM2.5 and PM10. Furthermore, the PM was sampled using a Handi-vol sampler, and the physicochemical characteristics were determined by SEM-EDS analysis. Trajectories, dispersion and deposition of the emitted material were calculated using the NOAA-HYSPLIT model. Urinary 1-hydroxypyrene (1-OHP) levels were analyzed by HPLC. DNA damage, chromosomal instability and cell death were measured by a buccal micronucleus cytome assay (BMCyt). The PM concentrations for all measurements in the exposed area were higher than in the non-exposed area. SEM-EDS analyses exhibited a wide variety of particles, and K, Cl, S and Ca biomass burning tracers were the major inorganic compounds. In addition, atmospheric modeling analysis suggested that these particles can reach regions farther away than 40 kilometers. Occupational polycyclic aromatic hydrocarbon exposure was confirmed by increases in 1-OHP levels in cashew nut workers. Frequencies of BMCyt biomarkers of genotoxicity (micronuclei and nuclear bud) and cytotoxicity (pyknosis, karyolysis, karyorrhexis and condensed chromatin) were higher in the exposed group compared with the controls. The influence of factors, such as age, on the micronuclei frequencies was demonstrated, and a correlation between 1-OHP and micronuclei was observed. To the best of our knowledge, no other study has demonstrated a correlation between these types of biomarkers. The use of exposure (1-OHP) and effect (BMCyt) biomarkers were therefore efficient in assessing the occupational risk associated with artisanal cashew nut roasting, and the high rates of PM2.5 are considered to be a potential contributor to this effect.
Supplied water in semiarid region was analyzed concerning heavy metals, cyanobacteria and radiation. Indoor radon and gamma emitters (U, K and Th) concentrations were measured. High radon levels are present inside urban residences. It was... more
Supplied water in semiarid region was analyzed concerning heavy metals, cyanobacteria and radiation. Indoor radon and gamma emitters (U, K and Th) concentrations were measured. High radon levels are present inside urban residences. It was found high frequencies of micronuclei and nuclear alterations in human oral mucosa. High background radioactivity could explain the observed mutagenic effect observed. a b s t r a c t Lucr ecia city, known to harbor a high cancer rate, is located in a semiarid region characterized by the presence of mineral reservoirs, facing a high exposure to metal and natural radioactivity. The present study aimed to assess the environmental scenario at a semiarid region located in Northeastern Brazil. Metal concentration, alpha and beta radiation, and cyanobacteria content in tap water along with indoor radon and gamma emitters (U, K and Th) concentrations were measured. In addition, mutagenic and nuclear instability effects were assessed using buccal micronucleus cytome assay. The study included five samplings corresponding to a period between 2007 and 2009. Drinking water from Lucr ecia city presented levels of Mn, Ni and Cr along with cyanobacteria in concentrations one to four times higher than regulatory guidelines considered. Furthermore, high levels of all the tested radionuclides were found. A high percentage of the houses included in this study presented indoor radon concentrations over 100 Bq m À3. The mean annual effective dose from Lucr ecia houses was six times higher than observed in a control region. The levels of exposure in most of the Lucr ecia houses were classified as middle to high. A significant mutagenic effect, represented as an increase of micronuclei (MN) frequency and nuclear abnormalities as nuclear buds (NB), binucleated cells (BN), and pyknotic cells (PYC) were found. The results obtained highlight the role of high background radioactivity on the observed mutagenic effect and could help to explain the exacerbated cancer rate reported in this locality.
The Buccal Micronucleus Cytome Assay (BMCyt) has become an important biomonitoring tool for assessing cytogenetic damage in many studied populations. Each laboratory applies protocols that vary according to the method of collecting and... more
The Buccal Micronucleus Cytome Assay (BMCyt) has become an important biomonitoring tool for assessing cytogenetic damage in many studied populations. Each laboratory applies protocols that vary according to the method of collecting and preparing samples. Besides, Brazil is a country of great territorial extensions that received immigrants from various parts of the world with different genetic backgrounds. Therefore, the present study aimed to evaluate the inter-laboratory variation in scoring the same set of slides using the more comprehensive scoring criteria, to standardize the BMCyt protocol, to observe the basal alterations in populations of different Brazilian regions and to compare it with other places around the world. Our results showed that a valuable number of laboratories participated, ten laboratories from different regions of the country, for the validation of the BMCyt in human biomonitoring studies, resulting in the 804 healthy individuals. This was possible because we observed: a range of measures needs to be considered, such as the baseline frequency of DNA damage and cell death in non-exposed individuals; age when grouped showed an influence on DNA damage, although when evaluated by group we did not see an influence; association between smoking habit and all endpoints of the BMCyt (except karyolytic cells) was evident; the basal MN frequency, in the majority of groups, follows those around the world; and the BMCyt was confirmed as a good health status biomarker. We emphasize the need for constant discussions on the parameters of cell death due to greater difficulty among the analyzers.
Smoking causes genetic damage associated with increased risk of oral cancer. Cigarette smoking induces genetic aberrations and micronucleus assay is a great biomarker to study the effect of smoking in human population. The present study... more
Smoking causes genetic damage associated with increased risk of oral cancer. Cigarette smoking induces genetic aberrations and micronucleus assay is a great biomarker to study the effect of smoking in human population. The present study was undertaken to detect incidence of nuclear anomalies in the exfoliated buccal epithelial cells of smokers using micronucleus assay. 100 healthy individuals (48 smokers and 52 non-smokers) were chosen randomly for the present study. A significantly high frequency of micronuclei was observed in the smokers (p<0.01) as compared to non-smokers. There was significant difference (p<0.05) in the frequency of binucleate cells and karyolysis depicting increased damage in the smokers. A dose-response relationship was observed between smoking and DNA damage.
Smoking causes genetic damage associated with increased risk of oral cancer. Cigarette smoking induces genetic aberrations and micronucleus assay is a great biomarker to study the effect of smoking in human population. The present study... more
Smoking causes genetic damage associated with increased risk of oral cancer. Cigarette smoking induces genetic aberrations and micronucleus assay is a great biomarker to study the effect of smoking in human population. The present study was undertaken to detect incidence of nuclear anomalies in the exfoliated buccal epithelial cells of smokers using micronucleus assay. 100 healthy individuals (48 smokers and 52 non-smokers) were chosen randomly for the present study. A significantly high frequency of micronuclei was observed in the smokers (p<0.01) as compared to non-smokers. There was significant difference (p<0.05) in the frequency of binucleate cells and karyolysis depicting increased damage in the smokers. A dose-response relationship was observed between smoking and DNA damage.
