[Heat and burden of diseases: impacts and future projections in capitals of the Legal Amazon.] / Calor y carga de enfermedades: impactos y proyecciones futuras en capitales de la Amazonía Legal.

OBJECTIVE: Under the influence of climate change, environmental exposure to heat and pollution grows, exacerbated by extreme events, increasing the risk of mortality in vulnerable areas. We aimed to evaluate the present (2000-2019) and future effects of heat on the burden of cardiovascular (in people aged 45 years or older), respiratory (in people aged 60 years or older) and all-cause (in people aged 1 year or more) diseases in capitals of the Legal Amazon (Brazil). METHODS: An ecological study was conducted to initially estimate, for the period 2000-2019, the relative risk (RR) of exposure-response related to the effects of temperature on years of life potentially lost (YLL) using the generalized linear regression model (GLM), combined with the distributed non-linear lag model (DLNM); and the fractions of YLL attributable to heat from the prospective perspective (forward). Subsequently, the results were estimated in the baseline period (1970-2005) and projected into the future in the specific levels of warming and periods: 1.5 ºC (2010-2039), 2 ºC (2040-2069) and 4 ºC (2070-2099), considering the temperature data from the WCRP CORDEX regional climate model in RCP8.5 scenario. RESULTS: The RR of YLL increased significantly in the capitals due to exposure to heat and marked thermal amplitudes between 2000-2019, with the major effects on respiratory diseases in Río Blanco (14%), due to all causes in Manaus (12%) and cardiovascular in Cuiabá (9%). Compared with the baseline period, the period 2040-2069 showed the largest increase (10.40 times) in the fraction of the number of YLL attributable to heat in the region, with the predominance of cardiovascular diseases. The findings were not completely conclusive, the low precision of the estimated confidence intervals did not show the significance of the negative effect of heat. CONCLUSIONS: Regardless of its significance, heat increases the risk of years of life lost in the short and medium term. The results support the need to include climate change mitigation and adaptation measures as public health protection policies.

OBJETIVO: Bajo la influencia del cambio climático crece la exposición ambiental al calor y a la contaminación, exacerbados por eventos extremos, incrementando el riesgo de mortalidad en áreas vulnerables. En este trabajo se evaluaron los efectos presentes (2000-2019) y futuros del calor sobre la carga de enfermedades cardiovasculares (en personas con 45 años o más), respiratorias (en personas con 60 años o más) y por todas las causas (en personas con 1 año o más) en capitales de la Amazonía Legal (Brasil). METODOS: Se realizó un estudio ecológico. Se estimaron inicialmente, para el período 2000-2019, el riesgo relativo (RR) de exposición-respuesta relacionado a los efectos de la temperatura sobre los años de vida potencialmente perdidos (AVPP) mediante el modelo de regresión lineal generalizada (GLM), combinado con el modelo no lineal de desfasajes (lag) distribuidos (DLNM); y las fracciones de AVPP atribuibles al calor desde la perspectiva prospectiva (forward). Posteriormente los resultados fueron estimados en período base (1970-2005) y proyectados a futuro en los niveles específicos de calentamiento y períodos: 1,5 ºC (2010-2039), 2 ºC (2040-2069) y 4 ºC (2070-2099), considerando los datos de temperatura del modelo climático regional WCRP CORDEX en escenario RCP8.5. RESULTADOS: Entre 2000-2019 el RR de AVPP se incrementó significativamente en las capitales ante la exposición al calor y las marcadas amplitudes térmicas, con los mayores efectos sobre las enfermedades respiratorias en Río Blanco (14%), por todas las causas en Manaos (12%) y cardiovasculares en Cuiabá (9%). Comparado con el período base, el período 2040-2069 mostró el mayor aumento (10,40 veces) de la fracción de número de AVPP atribuibles al calor en la región, con predominio de las causas cardiovasculares. Los hallazgos encontrados no fueron totalmente concluyentes, la baja precisión de los intervalos de confianza estimados no mostró significancia en el efecto negativo del calor. CONCLUSIONES: Independiente de su significancia, el calor aumenta el riesgo de AVPP a corto y mediano plazo. Los resultaron sustentan la necesidad de inclusión de medidas de mitigación y adaptación al cambio climático como políticas públicas de protección a la salud.

An Assessment of Health Outcomes and Methylmercury Exposure in Munduruku Indigenous Women of Childbearing Age and Their Children under 2 Years Old.

In line with the 1000-day initiative and the Sustainable Development Goals (SDG) 2 and 3, we present a cross-sectional analysis of maternal health, infant nutrition, and methylmercury exposure within hard-to-reach indigenous communities in the state of Pará, Brazilian Amazon. We collected data from all women of childbearing age (i.e., 12-49) and their infants under two years old in three Munduruku communities (Sawré Muybu, Sawré Aboy, and Poxo Muybu) along the Tapajos River. We explored health outcomes through interviews, vaccine coverage and clinical assessment, and determined baseline hair methylmercury (H-Hg) levels. Hemoglobin, infant growth (Anthropometric Z scores) and neurodevelopment tests results were collected. We found that 62% of women of childbearing age exceeded the reference limit of 6.0 µg/g H-Hg (median = 7.115, IQR = 4.678), with the worst affected community (Sawré Aboy) registering an average H-Hg concentration of 12.67 µg/g. Half of infants aged under 24 months presented with anemia. Three of 16 (18.8%) infants presented H-Hg levels above 6.0 µg/g (median: 3.88; IQR = 3.05). Four of the 16 infants were found to be stunted and 38% of women overweight, evidencing possible nutritional transition. No infant presented with appropriate vaccination coverage for their age. These communities presented with an estimated Infant Mortality Rate (IMR) of 86.7/1000 live births. The highest H-Hg level (19.6 µg/g) was recorded in an 11-month-old girl who was found to have gross motor delay and anemia. This already vulnerable indigenous Munduruku community presents with undernutrition and a high prevalence of chronic methylmercury exposure in women of childbearing age. This dual public health crisis in the context of wider health inequalities has the potential to compromise the development, health and survival of the developing fetus and infant in the first two critical years of life. We encourage culturally sensitive intervention and further research to focus efforts.

Intergenerational Association of Short Maternal Stature with Stunting in Yanomami Indigenous Children from the Brazilian Amazon.

To describe the factors associated to stunting in <5-year-old Yanomami Brazilian children, and to evaluate the association of short maternal stature to their offspring's stunting. A cross-sectional study carried out in three villages in the Yanomami territory. We performed a census, in which all households with children < 5-years-old were included. The length/height-for-age z-score <-2 standard deviations was used to classify the children as stunted. Short maternal height was defined as <145 cm for adult women, and <-2 standard deviations of the height-for-age z-score for adolescent women. We used adjusted Poisson regression models to estimate prevalence ratios (PR) along the 90% confidence interval. We evaluated 298 children. 81.2% of children suffered from stunting and 71.9% of the mothers from short stature. In the bivariate analysis, a significant association of stunting with short maternal stature, gestational malaria and child's place of birth were observed. Considering the variables of the children under five years of age, there were significant associations with age group, the child's caregiver, history of malaria, pneumonia, and malnutrition treatment. In the adjusted hierarchical model, stunting was 1.22 times greater in the offspring of women with a short stature (90% CI: 1.07-1.38) compared to their counterparts. Brazilian Amazonian indigenous children living in a remote area displayed an alarming prevalence of stunting, and this was associated with short maternal height, reinforcing the hypothesis of intergenerational chronic malnutrition transmission in this population. In addition, children above 24 months of age, who were born in the village healthcare units and who had had previous treatment in the past for stunting presented higher rates of stunting in this study.

Challenges and Prospects for Integrating the Assessment of Health Impacts in the Licensing Process of Large Capital Project in Brazil.

Brazil was one of the first countries in Latin America to institutionalize a National Environmental Policy in 1981, including the environmental impact assessment (EIA) process of economic activities with anticipated impacts on the environment. Today, EIA practice in Brazil comes with a number of limitations: it is constrained by its environmental advocacy role; application is strongly oriented towards large capital projects; and social responsibility considerations are only partially included. Consequently, EIA studies mainly address issues connected to localised and direct environmental impacts, largely ignoring any socio-economic and health impacts. This perspective paper highlights limitations of current EIA practice in Brazil with a focus on health considerations in impact assessment. While recognizing the positive impact to municipalities where large capital projects are being developed and operated, adverse impacts on health are a reality with measurable evidence in Brazil. Therefore, we argue that specificities on how to systematically assess and monitor potential health impacts cannot remain invisible in the Brazilian legislation, as currently seen in the reformulation of the licensing process in the country. The process of better integrating the assessment of health impacts in the licensing process of large capital project in Brazil must, however, not be based on the imposition of an external model but should be promoted by internal stakeholders from the environmental and health sector, incorporating the experiences gained in various case studies from all over the country.

Biomass burning particles in the Brazilian Amazon region: Mutagenic effects of nitro and oxy-PAHs and assessment of health risks.

Emissions from burning of biomass in the Amazon region have adverse effects on the environment and human health. Herein, particulate matter (PM) emitted from biomass burning in the Amazon region during two different periods, namely intense and moderate, was investigated. This study focused on: i) organic characterization of nitro- and oxy-polycyclic aromatic hydrocarbons (PAHs); ii) assessment of the excess lifetime cancer risk (LCR); and iii) assessment of the in vitro mutagenic effects of extractable organic matter (EOM). Further, we compared the sensitivity of two mutagenicity tests: Salmonella/microsome test and cytokinesis-block micronucleus (CBMN) with human lung cells. Among the nitro-PAHs, 2-nitrofluoranthene, 7-nitrobenz[a]anthracene, 1-nitropyrene, and 3-nitrofluoranthene showed the highest concentrations, while among oxy-PAHs, 2-metylanthraquinone, benz[a]anthracene-7,12-dione, and 9,10-anthraquinone were the most abundant. The LCR calculated for nitro-PAH exposure during intense biomass burning period showed a major contribution of 6-nitrochrysene to human carcinogenic risk. The EOM from intense period was more mutagenic than that from moderate period for both TA98 and YG1041 Salmonella strains. The number of revertants for YG1041 was 5-50% higher than that for TA98, and the most intense responses were obtained in the absence of metabolic activation, suggesting that nitroaromatic compounds with direct-acting frameshift mutagenic activity are contributing to the DNA damage. Treatment of cells with non-cytotoxic doses of EOM resulted in an increase in micronuclei frequencies. The minimal effective dose showed that Salmonella/microsome test was considerably more sensitive in comparison with CBMN mainly for the intense burning period samples. This was the first study to assess the mutagenicity of EOM associated with PM collected in the Amazon region using Salmonella/microsome test. The presence of compounds with mutagenic effects, particularly nitro- and oxy-PAHs, and LCR values in the range of 10-5 indicate that the population is potentially exposed to an increased risk of DNA damage, mutation, and cancer.

Genetic damage of organic matter in the Brazilian Amazon: a comparative study between intense and moderate biomass burning.

BACKGROUND: The biomass burning that occurs in the Amazon region has an adverse effect on environmental and human health. However, in this region, there are limited studies linking atmospheric pollution and genetic damage. OBJECTIVE: We conducted a comparative study during intense and moderate biomass burning periods focusing on the genetic damage and physicochemical analyses of the particulate matter (PM). METHOD: PM and black carbon (BC) were determined; organic compounds were identified and quantified using gas chromatography with flame ionization detection, the cyto-genotoxicity test was performed using two bioassays: cytokinesis-block micronucleus (CBMN) in A549 cells and Tradescantia pallida micronucleus (Trad-MCN) assay. RESULTS: The PM10 concentrations were lower than the World Health Organization air quality standard for 24h. The n-alkanes analyses indicate anthropogenic and biogenic influences during intense and moderate biomass burning periods, respectively. Retene was identified as the most abundant polycyclic aromatic hydrocarbon during both sampling periods. Carcinogenic and mutagenic compounds were identified. The genotoxic analysis through CBMN and Trad-MCN tests showed that the frequency MCN from the intense burning period is significantly higher compared to moderate burning period. CONCLUSIONS: This is the first study using human alveolar cells to show the genotoxic effects of organic PM from biomass burning samples collected in Amazon region. The genotoxicity of PM can be associated with the presence of several mutagenic and carcinogenic compounds, mainly benzo[a]pyrene. These findings have potential implications for the development of pollution abatement strategies and can minimize negative impact on health.

Iron status as a covariate in methylmercury-associated neurotoxicity risk.

Intrauterine methylmercury exposure and prenatal iron deficiency negatively affect offspring's brain development. Since fish is a major source of both methylmercury and iron, occurrence of negative confounding may affect the interpretation of studies concerning cognition. We assessed relationships between methylmercury exposure and iron-status in childbearing females from a population naturally exposed to methylmercury through fish intake (Amazon). We concluded a census (refuse <20%) collecting samples from 274 healthy females (12-49 years) for hair-mercury determination and assessed iron-status through red cell tests and determination of serum ferritin and iron. Reactive C protein and thyroid hormones was used for excluding inflammation and severe thyroid dysfunctions that could affect results. We assessed the association between iron-status and hair-mercury by bivariate correlation analysis and also by different multivariate models: linear regression (to check trends); hierarchical agglomerative clustering method (groups of variables correlated with each other); and factor analysis (to examine redundancy or duplication from a set of correlated variables). Hair-mercury correlated weakly with mean corpuscular volume (r=.141; P=.020) and corpuscular hemoglobin (r=.132; .029), but not with the best biomarker of iron-status, ferritin (r=.037; P=.545). In the linear regression analysis, methylmercury exposure showed weak association with age-adjusted ferritin; age had a significant coefficient (Beta=.015; 95% CI: .003-.027; P=.016) but ferritin did not (Beta=.034; 95% CI: -.147 to .216; P=.711). In the hierarchical agglomerative clustering method, hair-mercury and iron-status showed the smallest similarities. Regarding factor analysis, iron-status and hair-mercury loaded different uncorrelated components. We concluded that iron-status and methylmercury exposure probably occur in an independent way.

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.