Frequencies of micronuclei in buccal cells and their spatial distribution in a population living in proximity to coal mining areas in southern Brazil

The extraction and burning of coal release genotoxic pollutants, and understanding the relationship between genetic damage and the spatial distribution of residences in coal-using regions is crucial. The study aimed to conduct a spatial analysis of genotoxic damage through the of micronuclei (MNs) number and their proximity to coal mining/burning in the largest coal exploration region in Brazil. In this study, the detection of genotoxic damage was performed using the MN assay in oral cells of residents exposed to coal mining activities. Spatial analysis was conducted using QGIS 3.28.10 based on information obtained from a questionnaire administered to the population. Multiple linear regression analysis was carried out to assess the influence of the distance from residential areas to polluting sources on the number of MNs found. Additionally, Spearman's correlation was performed to identify the strength and direction of the association between the frequency of MNs and each of the polluting sources. A total of 147 MNs were quantified among all participants in the coal mining region. Notably, residents living within 2 km and 10 km of pollution sources exhibited the highest prevalence of MNs. The analysis demonstrated a significant correlation between closer proximity to pollution sources and increased MN frequency, underscoring the spatial relationship between these sources and genotoxic damage. Environmental pollutants from anthropogenic sources present a major health risk, potentially leading to irreversible damage. The spatial analysis in this study highlights the importance of targeted public policies. These policies should aim for a sustainable balance between economic development and public health, promoting effective measures to mitigate environmental impacts and protect community health.

Human health risk assessment of air pollutants in the largest coal mining area in Brazil

The Candiota region, located in the extreme south of Brazil, has the largest mineral coal deposit in the country, and this activity is capable of releasing pollutants in which they are associated with the contamination of different matrices (soil, water, and air). The present study aimed to carry out a risk assessment to human health of atmospheric pollutants NO₂ and SO₂ and PM₁₀-bound metal(loid)s in the municipality of Candiota, in addition to evaluating the correlation of meteorological parameters for the dynamics and potential risk of these pollutants. Pollutants were sampled from stations located almost 4 km from coal exploration activities, and the trace elements As, Cd, Se, Pb, and Ni, in addition to NO₂ and SO₂, were evaluated. Risk assessment was conducted taking into account the risk to adults via the inhalation route. During the sampling period, all pollutants presented values lower than national legislation or internationally accepted values, and Pb was the element that presented the highest values throughout the sampled period. The risk assessment showed no carcinogenic and non-carcinogenic risks, even when considering the sum of the risk of all analyzed pollutants. It can be observed that the highest levels of Pb, As, and Se occurred in the winter season, while the levels of Ni and Cd were higher in the spring, and the meteorological parameters were correlated with the pollutants, even using a temporal lag of 5 days. Although the air pollutants evaluated did not present a risk to human health, continuous monitoring of regions with strong mineral exploration activity must be carried out with a view to maintaining the well-being of exposed populations, mainly because there are people living in areas closer to sources of coal pollution than distance to air quality monitoring stations.

Emissions monitoring and carcinogenic risk assessment of PM10-bounded PAHs in the air from Candiota's coal activity area, Brazil

The city of Candiota contains a great amount of coal resources. Coal activities, including coal combustion, are major releasers of polycyclic aromatic hydrocarbons (PAHs). The PAHs are considered priority air pollutants regarding their large carcinogenic potential. So, the carcinogenic risk assessment of populations living near areas with PAH sources is mandatory. This study aimed to evaluate the carcinogenic health risk of the PAH inhalation exposure of individuals living in Candiota City. A total of 158 individuals were enrolled in the study. Monitoring of PAH and meteorological parameters were carried out, and the health risk assessment was determined through the benzo(a)pyrene equivalent toxic equivalent quotient (BaP-TEQ) and the incremental lifetime cancer risk (ILCR) estimation. The coal activity area of Candiota demonstrated an annual PAH concentration of 27.7 ng/m³, PM10 concentration of 26.3 µg/m³, SO₂ concentration of 9.5 µg/m³, a BaP-TEQ value of 0.3 ng/m³, and a daily inhalation of 62.4 ng/day. The comparison among seasons showed no difference in PAH concentration and BaP-TEQ. It was observed ILCR values of 2.8 × 10^-6 and 2.6 × 10^-6 for estimation based on reference and real values, respectively, and these levels were above the reference limit of 10^-6, indicating cancer risk. Therefore, an epidemiological survey of cancer cases in the region and its relationship with environmental exposure and air pollutants levels must be required.

Multiple exposure pathways and health risk assessment of potentially harmful elements for children and adults living in a coal region in Brazil

Energy generated by coal can contaminate the environment by releasing toxic elements, including metals. The human health risk assessment (HHRA) associated with geographic information system (GIS) tools can assist the management of contaminated areas, such as coal mining areas. The objective of the study was to carry out the assessment and spatialization of the risk to human health of potentially hazards elements (PHEs) in the soil for children and adults, from multiple exposure routes (oral, inhalation and dermal) in the Candiota mines, largest coal mining region of Brazil. The non-carcinogenic risks (HQ) of PHEs (Cu, Pb, Zn, Ni, Cr, Fe, Mn, Cd, As and Se) and carcinogenic risks of As were estimated and spatialized. The results revealed a risk for children exposure to Mn, with greatest contribution through dermal route. Mn (HQ_derm 72.41-96.09% and HQ_inh 40.84-82.52%) and Fe (HQ_o 43.90-81.44%) were the metals with greatest contribution to human health risk among studied population. As did not present carinogenic risk to adults. The spatial distribution of non-carcinogenic risk showed that Cr, As, Fe, Pb, Ni, Zn and Cu have higher HInc close to the coal mining areas, while Mn, Se and Cd have the highest HInc values in surrounding municipalities (Pinheiro Machado; Pedras Altas and Hulha Negra). The use of HHRA associated with GIS tools provides important elements for decision-making in the management of contaminated sites, indicating chemical elements, locations, routes of exposure and priority target populations.

Factors associated with genetic damage - an analysis integrating human populations from Southern Brazil

Socioeconomic and demographic factors, lifestyle and cultural characteristics may play an important role in the development of genetic damage. This damage represents a potential health risk to an individual and increases the risk of developing negative outcomes. The aim of this study was to investigate the association of a set of factors and genetic damage by gathering data from previously studied populations in southern Brazil. This study analyzed data related to genetic damage and socioeconomic, demographic, and lifestyle variables of 514 individuals aged 18 to 64 years, residing in 8 cities located in the extreme south of the Brazil. A total of twelve factors were considered in the analysis, and of these seven had some association with the frequency of micronucleus or some parameter of the comet assay. Interestingly, age was a factor weakly associated with genetic damage, while skin color, occupational exposure, drug use, exposure to radiation, and the cultural habit of consuming chimarrão were shown to be associated with genetic damage when analyzed using multivariate regression. Therefore, we suggest that yerba mate consumption is a confounding factor and should be considered in cytogenetic studies in the southern region of South America. These results reinforce the need for human biomonitoring studies to include consideration of a broad range of population and cultural characteristics when seeking to identify relevant associations.

Gestational and Neonatal Outcomes in Cities in the Largest Coal Mining Region in Brazil

Brazil has one of the largest mineral coal reserves in the world. More than 40% of this ore is in the Candiota Mine, in the extreme south of Brazil, which was previously identified as a hotspot of environmental pollution. In addition, an important part of Brazil's population suffers from socioeconomic vulnerability. Since there is no information on unfavorable gestational and neonatal outcomes associated with these problems, we conducted a cross-sectional study with 1950 mother-child binomials, aiming to evaluate the association between these outcomes and air pollution as well as socioeconomic, demographic and health variables in seven cities in the region. Of the total births, 11.6% were preterm and 9.5% of neonates had low birth weight (<2500 g). These conditions were also associated with skin color, previous abortions, birth type and prenatal care, as well as exposure to higher levels of coarse particulate matter (PM₁₀) during the first trimester of pregnancy. Regarding air pollutants, although the daily limits for PM₁₀ were exceeded on less than 5% of days, the annual average overtook the values proposed by WHO. Thus, we concluded that prematurity and low birth weight in this region are related to air pollution, and to socioeconomic variables and health care.

Lung function among residents from the largest coal region in Brazil

Coal mining and burning activities in coal-fired power plants are among the most polluting activities in developing countries. In Brazil, the Candiota coal deposit concentrates 40% of the national mineral coal. Although, previous studies indicate several negative health outcomes to residents of this coal region, there is no information about lung function. Thus, this study aimed to evaluate lung function by spirometry among residents from the largest coal mining region of Brazil and its related factors. It was carried out a cross-sectional study with 300 male adults residing in four cities from this region. Socioeconomic, demographic, life style, and health conditions were collected through a structured questionnaire, and lung function was assessed by spirometry. Almost 18% of the residents have disorders in pulmonary function. There was significant statistical difference in the spirometry main parameters between the cities. Candiota city (host city of coal exploration activities) have the highest prevalence of obstructive ventilatory disorder. Curiously, upper economic class had significant higher risk of altered lung function (P<0.001), as well as inappropriate sewage destination (P<0.001). Residents of Candiota city had 20% higher risk of altered lung function. Regarding air quality, the PM₁₀, SO₂, and NO₂ of the region were 20.6± 3.9, 7.0± 2.2, and 6.0± 1.6, respectively. Two air quality stations exceed the limit of 20 μg/m³ to PM₁₀ proposed by Brazilian legislation and WHO, and three stations had PM₁₀ quite close to the limit. This study points out the need for urgent action to protect residents from this coal mining region.

Brazilian workers occupationally exposed to different toxic agents: A systematic review on DNA damage

The evaluation of genotoxicity in workers exposed to different toxic agents is very important, especially considering the association between these exposures in a chronic context and DNA damage. Assessing biomarkers of exposure and, when possible, early biomarkers of effect, contributes to elucidating the potential toxic mechanisms involved in genotoxicity and its contribution to chronic non-communicable diseases. In Brazil, the biggest country in South America, workers are exposed to hazardous physical and chemical agents. Considering that these exposures occur, in most cases, throughout the worker's whole life, this is an important public health concern in Brazil. Therefore, this systematic review aims to analyze occupational exposure to chemical and physical agents and the association with DNA damage in studies carried out in Brazil from 1980 to 2021. A systematic and comprehensive literature search was performed in different databases based on occupational exposure to chemical and physical agents and DNA damage. Only full articles on studies that investigated experimental evidence on occupational exposure in Brazil and assessed DNA damage were included, amounting to 89 articles. Five main occupational exposure groups were identified: pesticides (36%), organic solvents (20%), dust and particles (16%), metals (11%), and ionizing radiation (6%). Another group called "others" included studies (11%) that did not fall into these main groups. It was found that comet assay and micronucleus tests are the most adopted methods to detect DNA damage. Occupational exposures were most associated with DNA damage. However, further improvements in study design would be needed to better characterize the association between biomonitoring and DNA damage, particularly to account for confounding factors.

Health impact assessment of air pollution in an area of the largest coal mine in Brazil

Coal exploration and burning activities are among the activities with the greatest potential to cause atmospheric pollution due to the combustion process of this mineral and the consequent release of particles that, in significant quantities, can pose a potential health risk, mainly respiratory and cardiovascular diseases. The Candiota region, in the extreme south of Brazil, concentrates 40% of the national reserves of mineral coal, and its burning is capable of releasing air pollutants, including particulate matter (PM). Some environmental and epidemiological studies have been carried out in the region, but so far, there is no investigation to estimate the impact of PM on health outcomes. The current study aimed to estimate the mortality attributed to the PM, as well as the benefits in health indicators associated with the reduction of air pollution to the limits set forth in local legislation and the WHO. Daily data on PM levels collected from an air quality monitoring station over a year were used, as well as population data and health indicators from 7 cities influenced by mining activities, such as total mortality and cardiovascular diseases and hospitalizations for cardiac and respiratory problems. In a scenario where PM levels are within legal limits, a percentage greater than 11% of cardiovascular deaths was attributed to pollution by PM2.5, and the reduction in PM10 and PM2.5 levels may be responsible for the increase in the expectation of life in up to 17 months and monetary gains of more than $ 24 million, due to the reduction in hospitalizations and mortality. Studies of this nature should be important tools made available to decision-makers, with a view to improving environmental laws and a consequent improvement in the quality of life and health indicators of the population.

Human health risk assessment of metals and anions in surface water from a mineral coal region in Brazil

Coal mining releases high concentration elements to the environment, which can be deposited in surface water, causing several human health problems. Candiota mine in the south of Brazil is the largest coal reserves in the country, representing approximately 40% of total national coal reserves. Therefore, the present study aimed to estimate the chronic daily dose and the non-carcinogenic risk index for metals and anions in surface waters of Candiota Region, using the USEPA protocols for Human Health Risk Assessment. A total of eight water samples were collected over a distance of up to 15 km from the emission sources of the thermal power generation companies, then the Chronic Daily Intake (CDI), Hazard Quotient (HQ), Hazard Index (HI), and sum of Hazard Index (ΣHI) were calculated. All the elements and anions evaluated showed natural concentrations for continental fresh waters according to Brazilian legislation, except Pb. Individually, none of the metals Pb, As, Cd, Ni, and Se or anions F^- and NO₃^- showed an HI value greater than 1. However, the sum of HI (ΣHI) (five metals and two anions) by sample point showed values close to 1, for one of the eight points analyzed. Pb and Fe were the elements that most contribute to the risk values in the sample points of the study area. Although, there is no human health risk in this scenario, this investigation highlight priority elements to future investigations in coal mine areas. In the current region, Pb and F^- as priority elements for future studies.

Maternal, neonatal and socio-economic factors associated with intellectual development among children from a coal mining region in Brazil

Coal is the most aggressive energy sources in the environment. Several adverse outcomes on children's health exposure to coal pollutants have been reported. Pollutants from coal power plants adversely affect the intellectual development and capacity. The present study aimed to evaluate the intellectual development and associated factors among children living a city under the direct influence (DI) and six neighboring municipalities under the indirect influence (II) of coal mining activity in the largest coal reserve of Brazil. A structured questionnaire was completed by the child's guardian, and Raven's Progressive Color Matrices were administered to each child to assess intellectual development. A total of 778 children participated. In general, no significant difference was observed between the two cities. The DI city had better socioeconomic conditions than the II municipalities according to family income (< 0.001). The prevalence of children who were intellectually below average or with intellectual disabilities was 22.9%, and there was no significant difference (p > 0.05) between municipalities. In both unadjusted and adjusted analyses, intellectual development was associated with maternal age, marital situation and maternal education level, birth weight, breast feeding, frequent children's daycare, paternal participation in children's care and child growth. Living in the DI area was not associated with intellectual disability. The results suggest that socioeconomic conditions and maternal and neonatal outcomes are more important than environmental factors for intellectual development of children living in a coal mining area.

Genetic damage in coal and uranium miners

Mining has a direct impact on the environment and on the health of miners and is considered one of the most hazardous occupations worldwide. Miners are exposed to several occupational health risks, including genotoxic substances, which may cause adverse health effects, such as cancer. This review summarizes the relation between DNA damage and mining activities, focusing on coal and uranium miners. The search was performed using electronic databases, including original surveys reporting genetic damage in miners. Additionally, a temporal bibliometric analysis was performed using an electronic database to create a map of cooccurrence terms. The majority of studies were performed with regard to occupational exposure to coal, whereas genetic damage was assessed mainly through chromosomal aberrations (CAs), micronuclei (MNs) and comet assays. The bibliometric analysis demonstrated associations of coal exposure with silicosis and pneumoconiosis, uranium miners with lung cancer and tumors and some associated factors, such as age, smoking, working time and exposure to radiation. Significantly higher DNA damage in miners compared to nonexposed groups was observed in most of the studies. The timeline reveals that classic biomarkers (comet assay, micronucleus test and chromosomal aberrations) are still important tools to assess genotoxic/mutagenic damage in occupationally exposed miners; however, newer studies concerning genetic polymorphisms and epigenetic changes in miners are being conducted. A major challenge is to investigate further associations between miners and DNA damage and to encourage further studies with miners of other types of ores.

Multiple exposure pathways and health risk assessment of selenium for children in a coal mining area

Selenium (Se) presents a dual role to human body, harmful or beneficial, depending on its concentration. The exposure to this element has been associated to coal mining. Health risk assessment allows estimating and evaluating the risks that environmental hazards pose to vulnerable groups of populations. The present study aimed to analyze the risk of exposure to Se through multiple exposure pathways in children living in Candiota city, where the largest coal reserve of Brazil is located. Data from previous environmental (air, soil, drinking water, and food) and population parameters (age, weight, and food intake) were used to assess the health risk, which was calculated with real values (extracted from the population) and fixed reference values, based on the USEPA recommendation. Most of the children had low health risk (HQ < 1); however, in the most conservative scenarios (higher Se values in the different matrices), there was a high health risk in both scenarios, using population data or the USEPA parameters. The mean HQ using reference values was twice higher than using real values. Se content in air, soil, and drinking water did not represent important average daily dose in both scenarios. While, food intake was a main source of Se exposure, contributing with 96.9% of total Se intake. The findings of this study reinforce the importance of food intake for exposure to Se and the difference between HQs using population measures and fixed parameters of the USEPA highlights the need for adaptations to local scenarios for a better dimensioning of toxicological risk management actions.

Blood markers among residents from a coal mining area

Coal extraction and processing generate environmental contamination, which has several negative impacts on human health. Hematological and biochemical parameters are effective biomarkers of the exposure of a population to air pollutants. Thus, this study aimed to evaluate hematological and biochemical parameters in adult residents in a coal mining region in the largest national reserve in Brazil, as well as to investigate their relations with air quality. The study included three cities in the south of Brazil, which are located near an important power plant and coal mine. The air quality was analyzed by PM10, NOx, and SO₂ at five air quality monitoring stations, socioeconomic and demographic characteristics were evaluated with a questionnaire, and biochemical parameters were assessed in blood samples. The mean PM10 in the study area was 19.18 μg/m³. The air quality varied among the five monitoring stations, and the Candiota station exceeded the reference limit by 63.3%. In general, participants had lived more than 10 years in the municipality and had hepatic and renal parameters within the reference values. A higher prevalence of alterations was found in hematological parameters (43.1%) and liver function (30%). Among the three cities, the population of Pedras Altas seems to have a greater impairment of the blood parameters evaluated. The only parameter that was correlated with PM10 was the hematocrit level (r = 0.33; P < 0.001).

Genotoxic risk in health-care professionals occupationally exposed to low doses of ionizing radiation

The purpose of this study was to evaluate the potential influence of occupational ionizing radiation (IR) exposure on health professionals, assessing DNA damage using the comet and micronucleus (MN) assays and analyzing relative risks, correlations, and associated factors between outcomes and socioeconomic and lifestyle factors. Blood and buccal samples were collected from 36 workers, who actively participated in an imaging sector of a hospital, who were either exposed to IR directly or indirectly (9 internal control and 27 exposed), and 27 individuals living in the same city but with no occupational exposure (external control, unexposed/healthy). All radiation dosages performed on the 36 workers were less than 20 mSv/y, not exceeding the effective dose limit for occupational exposure. A questionnaire identified socioeconomic and lifestyle factors associated with the outcomes. The results of the MN assay showed a significant difference between both internal control and the exposed group when compared to the external control. For the comet assay, there were significant differences between the percent of tail DNA of the exposed group and external controls, but no difference was found between the exposed group and internal controls. Relative risk associations were found in time of exposure, hours worked per week, and perceived stress. Correlations were found between the outcomes and age, consumption of alcohol, and frequencies of X-rays during life. Variables that showed to be significant in the adjusted analysis were skin color and recent exposure to radiation. Albeit limited, the findings of this study suggest genotoxicity in both blood and buccal mucosa cells of workers exposed directly or indirectly to IR and that lifestyle and socioeconomic factors are associated and correlated with the risk of developing these outcomes.

Genotoxic risk in health-care professionals occupationally exposed to low doses of ionizing radiation

The purpose of this study was to evaluate the potential influence of occupational ionizing radiation (IR) exposure on health professionals, assessing DNA damage using the comet and micronucleus (MN) assays and analyzing relative risks, correlations, and associated factors between outcomes and socioeconomic and lifestyle factors. Blood and buccal samples were collected from 36 workers, who actively participated in an imaging sector of a hospital, who were either exposed to IR directly or indirectly (9 internal control and 27 exposed), and 27 individuals living in the same city but with no occupational exposure (external control, unexposed/healthy). All radiation dosages performed on the 36 workers were less than 20 mSv/y, not exceeding the effective dose limit for occupational exposure. A questionnaire identified socioeconomic and lifestyle factors associated with the outcomes. The results of the MN assay showed a significant difference between both internal control and the exposed group when compared to the external control. For the comet assay, there were significant differences between the percent of tail DNA of the exposed group and external controls, but no difference was found between the exposed group and internal controls. Relative risk associations were found in time of exposure, hours worked per week, and perceived stress. Correlations were found between the outcomes and age, consumption of alcohol, and frequencies of X-rays during life. Variables that showed to be significant in the adjusted analysis were skin color and recent exposure to radiation. Albeit limited, the findings of this study suggest genotoxicity in both blood and buccal mucosa cells of workers exposed directly or indirectly to IR and that lifestyle and socioeconomic factors are associated and correlated with the risk of developing these outcomes.

Distribution of potentially harmful elements in soils around a large coal-fired power plant

An understanding of the spatial distribution and contribution of a power plant to local soil contamination is important for the planning of soil use and prioritizing remedial actions for public safety. Consequently, the aim of this study was to map the spatial distribution of potentially hazardous elements (PHEs; Cu, Pb, Zn, Ni, Cr, Fe, Mn, Cd, As, and Se) in soils around a large (796 MW) coal-fired power plant in Brazil. For the purpose, 33 soil samples were collected in the area within a radius of approximately 17.5 km from the plant and subsequently analyzed for PHEs. The frequency and direction of winds were also obtained from a meteorological station in the region. The sampling area was divided into four quadrants (northwest: N-NW; northeast: N-NE; southeast: S-SE; southwest: S-SW), and there were significant negative correlations between the distance and the concentrations of Se in the S-SE quadrant and As in the S-SW and S-SE quadrants. There were positive correlations between distance from the plant and the concentration of Mn in the N-NE quadrant and the concentration of Cd in the S-SW quadrant. The dominant direction of the winds was N-NE. The indexes used in this study showed low-to-moderate enrichment factor, but detailed analysis of the dominant quadrant of the winds showed a correlation with higher concentrations in the soils closer to the power plant for at least seven of the PHEs analyzed, especially with regard to As. Therefore, we conclude that the distribution of the metalloid As can be used as a marker of the spatial distribution of contamination from the thermoelectric plant, but the dynamics of the other elements suggests that the presence of other sources of contamination may also compromise the quality of local soils.

Association between DNA damage, dietary patterns, nutritional status, and non-communicable diseases in coal miners

Several negative health effects have been associated with environmental pollution. Coal mining activities are related to DNA damage. However, the impact of lifestyle as well as environmental exposure must be considered when evaluating the extent of DNA damage. The aim of this cross-sectional study was to analyze nutritional status, dietary patterns, and the prevalence of non-communicable diseases (CNCDs) among coal miners as well as to investigate the correlation of these variables with DNA damage. We used a questionnaire to assess demographics, health, and dietary habits. The nutritional status was measured in terms of BMI (body mass index) and DNA damage was assessed by the comet assay. The sample population was composed of 158 coal miners from the largest coal mining company in South of Brazil, and majority of them were classified as overweight (51.3%) or obese (28.5%). Hypertension was the most common CNCD (50.6%) and a majority of these workers consumed all groups of foods three or more times a week. There was a significant positive correlation between BMI and DNA damage (r = 0.1646, p = 0.04) and this association was stronger (r = 0.2556, p = 0.04) in coal miners with some CNCD. There was no significant correlation between dietary patterns and DNA damage in coal miners. These results suggest that the nutritional status and CNCD increase the extent of DNA damage in coal miners. Since this population is at high occupational risk, specific strategies should be designed to improve the health of these workers, aiming to achieve health equity.