Sandra de Souza Hacon

Impact on human health of particulate matter emitted from burnings in the Brazilian Amazon region

OBJECTIVE To analyze the impact on human health of exposure to particulate matter emitted from burnings in the Brazilian Amazon region. METHODS This was an ecological study using an environmental exposure indicator presented as the percentage of annual hours (AH%) of PM2.5 above 80 microg/m3. The outcome variables were the rates of hospitalization due to respiratory disease among children, the elderly and the intermediate age group, and due to childbirth. Data were obtained from the National Space Research Institute and the Ministry of Health for all of the microregions of the Brazilian Amazon region, for the years 2004 and 2005. Multiple regression models for the outcome variables in relation to the predictive variable AH% of PM2.5 above 80 microg/m3 were analyzed. The Human Development Index (HDI) and mean number of complete blood counts per 100 inhabitants in the Brazilian Amazon region were the control variables in the regression analyses. RESULTS The association of the exposure indicator (AH%) was higher for the elderly than for other age groups (beta = 0.10). For each 1% increase in the exposure indicator there was an increase of 8% in child hospitalization, 10% in hospitalization of the elderly, and 5% for the intermediate age group, even after controlling for HDI and mean number of complete blood counts. No association was found between the AH% and hospitalization due to childbirth. CONCLUSIONS The indicator of atmospheric pollution showed an association with occurrences of respiratory diseases in the Brazilian Amazon region, especially in the more vulnerable age groups. This indicator may be used to assess the effects of forest burning on human health.

Atmospheric Mercury and Trace Elements in the Region of Alta Floresta in the Amazon Basin

In the early 1980’s the Amazon region in the North of Brazil was the scene of the most intense gold rush in the history of Brazil. Metallic mercury (Hg) in gold mining activities is used to amalgamate particulate gold. The other sources of Hg emissions in Amazonian are tailing deposits and biomass burning of tropical forests and savannas. Total Hg concentrations in the urban area of Alta Floresta ranged from 20 to 5800 ng/m3. Indoor total Hg concentration in gold shops ranged from 250 to 40600 ng/m3. Particulate Hg accounts for 5 to 20% of total Hg in Alta Floresta. Through Factor and cluster analysis it was obtained a pattern of relationships between total Hg, fine and coarse mode particulate Hg, Pt, Pb, Ag and several other trace elements associated with the amalgamation process. A clear correlation was also observed with the fine mode biomass burning aerosol and coarse mode soil dust.

Biogeochemistry of Mercury in the Amazonian Environment

Abstract In this paper, the processes that affect mercury (Hg) cycling in the Amazonian environment were reviewed, criticized and new directions of research are proposed. The discussion of the origin of the mercury contamination, whether natural or anthropogenic is marked by a lack of fundamented arguments from both sides. Undoubtedly mercury inputs from gold mining have locally increased environmental concentrations, but in the whole Amazon, these loads would be insignificant, considering the high concentrations observed by some authors in remote soils. A reasonable process that should explain these elevated concentrations in soil is that B horizons function as a mercury “sponge” that have been accumulating mercury over a geological time scale, releasing it back to cycling during erosion and forest fires. The environmental degradation of the Amazonian forest due to human activities is probably enhancing the release of that mercury to the cycle. Mercury transformations in reduced, anoxic environments—sediments and waters—are also a key problem for the understanding of the environmental methylation. The studies that have been carried out in the Amazonian environment are too restricted and results permit only circumstantial conclusions. Large efforts must be directed to monitoring programs considering time and space variability.

Análise das internações por doenças respiratórias em Tangará da Serra - Amazônia Brasileira

OBJECTIVE To analyze hospitalizations for respiratory diseases among children under 15 years of age in an area with high levels of environmental pollution. METHODS A cross-sectional study of hospitalizations due to respiratory diseases of patients residing in the city of Tangará da Serra, located in the state of Mato Grosso (Brazilian Amazon region), from 2000 to 2005. Data on hospital admissions were obtained from the Brazilian Unified Health Care System and from Brazilian Institute of Geography and Statistics population estimates. RESULTS In 2005, the rate of hospitalization for respiratory diseases among children under 15 years of age in the microregion of Tangará da Serra was 70.1/1,000 children. Between 2000 and 2005, there were 12,777 such admissions, of which 8,142 (63.7%) were for respiratory diseases. During the dry season (May to October), the rate of admissions for respiratory diseases was 10% higher than during the rainy season (November to April). The principal causes of admission included pneumonia (90.7%) and respiratory insufficiency (8.5%). Admissions of children under 5 years of age for pneumonia were 4 times the expected number for the city. Children under 12 months of age were the most frequently hospitalized, with an average increase of 32.4 admissions per 1,000 children per year. CONCLUSIONS Tangará da Serra presented a high number of pediatric admissions for respiratory diseases. Therefore, it is logical to consider it a priority area for investigation and monitoring of the environmental risk factors for such diseases.

Air pollution and hospital admissions for respiratory diseases in the subequatorial Amazon: a time series approach

The objective of the study is to evaluate the effect of the daily variation in concentrations of fine particulate matter (diameter less than 2.5 microm--PM2.5) resulting from the burning of biomass on the daily number of hospitalizations of children and elderly people for respiratory diseases, in Alta Floresta and Tangará da Serra in the Brazilian Amazon in 2005. This is an ecological time series study that uses data on daily number of hospitalizations of children and the elderly for respiratory diseases, and estimated concentration of PM2.5. In Alta Floresta, the percentage increases in the relative risk (%RR) of hospitalization for respiratory diseases in children were significant for the whole year and for the dry season with 3-4 day lags. In the dry season these measurements reach 6% (95%CI: 1.4-10.8). The associations were significant for moving averages of 3-5 days. The %RR for the elderly was significant for the current day of the drought, with a 6.8% increase (95%CI: 0.5-13.5) for each additional 10 microg/m3 of PM2.5. No associations were verified for Tangará da Serra. The PM2.5 from the burning of biomass increased hospitalizations for respiratory diseases in children and the elderly.

Associação entre material particulado de queimadas e doenças respiratórias na região sul da Amazônia brasileira

OBJETIVO: Investigar os efeitos de curto prazo da exposicao ao material particulado de queimadas da Amazonia na demanda diaria de atendimento ambulatorial por doencas respiratorias de criancas e de idosos. METODOS: Estudo epidemiologico com delineamento ecologico de series temporais. Os registros diarios de atendimento ambulatorial foram obtidos nas 14 unidades de saude do municipio de Alta Floresta, Mato Grosso, regiao sul da Amazonia brasileira, no periodo de janeiro de 2004 a dezembro de 2005. Informacao sobre os niveis diarios de material particulado fino foi disponibilizada pelo Instituto Nacional de Pesquisas Espaciais. Para controlar possiveis fatores de confusao (situacoes nas quais uma associacao nao causal entre exposicao e doenca e observada devido a uma terceira variavel), foram adicionadas ao modelo variaveis referentes a tendencia temporal, sazonalidade, temperatura, umidade relativa do ar, precipitacao pluviometrica e efeitos de calendario (como ocorrencia de feriados e finais de semana). Utilizou-se regressao de Poisson via modelos aditivos generalizados. RESULTADOS: Um incremento de 10 µg/m³ nos niveis de exposicao ao material particulado esteve associado a aumentos de 2,9 e 2,6% nos atendimentos ambulatoriais por doencas respiratorias de criancas no 6o e 7o dias subsequentes a exposicao. Nao foram encontradas associacoes significativas nos atendimentos de idosos. CONCLUSOES: Os resultados sugerem que os niveis de material particulado das queimadas na Amazonia estao associados a efeitos adversos a saude respiratoria de criancas.

Mudanças climáticas e ambientais e as doenças infecciosas: cenários e incertezas para o Brasil

Global climate and environmental change has been aggravating along the last decades but only circulated by the media over the recent years. This process poses a challenge to society and government on the causes and the role of environmental change on health conditions. This work aims to evaluate scenarios of climatic and environmental changes and their uncertainties for Brazil. The work also identifies resources that can be mobilized to develop a network for diagnosis, modeling, analysis and intervention on the results of these changes on health conditions. The main groups of diseases that may be affected by these changes are water related, vector-borne and respiratory diseases. However, the risks associated with global climate change can not be assessed separately from other processes such as globalization, environmental changes and instability of governmental systems. The health sector, must not only prevent these risks, but be active to reduce social vulnerability.

Genotoxicity and composition of particulate matter from biomass burning in the eastern Brazilian Amazon region

In the present study Tradescantia pallida micronucleus (Trad-MCN) bioassay was used to assess the genotoxicity of particulate matter with a mass median aerodynamic diameter less than 10 μm (PM₁₀) in Tangara da Serra (MT), a Brazilian Amazon region that suffers the impact of biomass burning. The levels of PM (coarse and fine size fractions) and black carbon (BC) collected were also measured. Furthermore, the alkanes and polycyclic aromatic hydrocarbons (PAHs) were identified and quantified in the samples taken during the burning period by gas chromatography with flame ionization detection (GC-FID). The PM and BC results for both fractions indicate a strong correlation (p < 0.001). The analysis of alkanes indicates an anthropic influence. Retene was the most abundant PAH found, an indicator of biomass burning, and 12 other PAHs considered to be potentially mutagenic and/or carcinogenic were identified in this sample. The Trad-MCN bioassay showed a significant increase in micronucleus frequency during the period of most intense burning, possibly related to the mutagenic PAHs that were found in such extracts. This study demonstrated that Trad-MCN was sensitive and efficient in evaluating the genotoxicity of organic compounds from biomass burning. It further emphasizes the importance of performing chemical analysis, because changes in chemical composition generally have a negative effect on many living organisms. This bioassay (ex situ), using T. pallida with chemical analysis, is thus recommended for characterizing the genotoxicity of air pollution.

Association between fine particulate matter and the peak expiratory flow of schoolchildren in the Brazilian subequatorial Amazon: A panel study ☆

BACKGROUND Exposure to high levels of particulate matter with an aerodynamic diameter less than 2.5 μm (PM(2.5)) resulting from biomass burning is frequent in the subequatorial Amazon region. OBJECTIVE To investigate whether or not current exposure to PM(2.5) in the Brazilian Amazon has adverse effects on the daily peak expiratory flow (PEF) of schoolchildren. METHODS The study design consisted of a panel comprising 309 children aged 6 to 15 years from the same school. PEF was measured daily, except weekends and holidays, from August to December 2006. Each child contributed to the study up to 67 daily measurements. All together there were 19115 PEF measures. Participation rate was 90%. Daily measurements of PM(2.5), temperature, and humidity as well as passive smoking, and subject features were regarded in the statistical analysis. Various exposures of PM(2.5) were considered throughout the analysis, among them 24-hour, 12-hour, 6-hour, and 5-hour means. To account for subject responses to confounders, mixed effects models were applied. The effects were evaluated considering air pollution levels on the current day or at 1- or 2-day lags and the averages of 0-1-day lags, 1-2-day lags and 0-, 1-, and 2-day lags. RESULTS The 24-hour PM(2.5) means ranged from 6.39 to 99.91 μg/m(3). The adjusted models for the entire group of children revealed adverse effects. For instance, for an increase of 10 μg/m(3) in PM(2.5,) the reduction in the PEF average varied between 0.26 l/min (95% Confidence Interval (CI): -0.49; -0.04) and 0.38 l/min (95% CI: -0.71; -0.04). Restricted to the subgroup of non-asthmatic children, classified as such according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, there was a reduction in the PEF ranging from 0.38 l/min (95% CI: -0.63; -0.13) to 0.53 l/min (95% CI: -0.90; -0.16) for an increase of 10 μg/m(3) in PM(2.5). There was no significant effect in the asthmatic group. When stratified by time of the day children were at school, the concurrent effects of air pollution on PEF were not significant, whereas the 6-hour exposure from 0 am to 5:30 am was significant for both morning and afternoon groups. Finally, the 24-hour mean lagged effect was only significant for the afternoon group of children. For an increase of 10 μg/m(3) in PM(2.5,) there was a reduction in the PEF that ranged from 0.41 l/min (95% CI: -0.76; -0.06) to 0.49 l/min (95% CI: -0.91; -0.07). CONCLUSION Exposure to current levels of PM(2.5) in the Brazilian Amazon was associated with reductions in the lung function of schoolchildren. The adverse effects were more consistent in non-asthmatic children and with respect to the 6-hour mean from 0 am to 5.30 am.

Risk Assessment of Mercury in Alta Floresta. Amazon Basin — Brazil

In the last 15 years gold mining activity has been the main source of the mercury (Hg) emissions into the atmosphere in the Amazon Basin. The first phase of gold production takes place in remote areas. In general the second one happens in the local urban area, where the gold is commercialized and sent to the great economic centers. In the last 3 years, this activity started to decline as a consequence of the high cost of the gold production but in the Municipality of Alta Floresta, the gold trade still plays an important role in the local economy. This paper addresses the assessment of the Hg exposure scenarios and their quantitative risk for inhalation of metallic Hg vapor and for ingestion of total Hg, using indirect exposure measurements, for different age groups of the urban area of Alta Floresta. This work took into account the field study which provided background information, such as characteristics of local and regional environment, Hg concentrations in different environmental media, and the character of the local urban population. The mean levels of Hg in the atmosphere of the urban area ranged from 210 ng/m3 to 880 ng/m3. Alta Floresta has no riverside population and there is a low fish consumption rate of 8 g/d among the general population. However, mercury levels in locally consumed carnivorous fish, ranged from 0.3 to 3.6 mg/kg, depending on the species and on the period of the year. The levels of mercury in soil surrounding the residential areas near the Hg emissions sources, ranged from 0.05 to 4.10 mg/kg. Hg in soil may represent an important source of mercury ingestion for local children up to 4 years of age. The mean Hazard Index estimated for the general adult population was 1.4. For the general population, regarding the number of persons exposed in the urban area, inhalation of metallic Hg vapor is the main route of exposure. The results for water ingestion for all groups are negligible. For families of fishermen the Hazard Index was estimated to be 9.3, with a contribution of 92% from fish ingestion.