Arsenic and mercury exposure in different insect trophic guilds from mercury mining areas in Mexico.

The exposure to arsenic and mercury in various insect trophic guilds from two mercury mining sites in Mexico was assessed. The two study sites were La Laja (LL) and La Soledad (LS) mines. Additionally, a reference site (LSR) was evaluated for LS. The terrestrial ecosystem was studied at LL, whereas both the terrestrial ecosystem and a stream called El Cedral (EC) were assessed at LS. The study sites are situated in the Biosphere Reserve Sierra Gorda (BRSG). Mercury vapor concentrations were measured with a portable analyzer, and concentrations of arsenic and mercury in environmental and biological samples were determined through atomic absorption spectrophotometry. Both pollutants were detected in all terrestrial ecosystem components (soil, air, leaves, flowers, and insects) from the two mines. The insect trophic guilds exposed included pollinivores, rhizophages, predators, coprophages, and necrophages. In LS, insects accumulated arsenic at levels 29 to 80 times higher than those found in specimens from LSR, and 10 to 46 times higher than those from LL. Similarly, mercury exposure in LS was 13 to 62 times higher than LSR, and 15 to 54 times higher than in LL. The analysis of insect exposure routes indicated potential exposure through air, soil, leaves, flowers, animal prey, carrion, and excrement. Water and sediment from EC exhibited high levels of arsenic and mercury compared to reference values, and predatory aquatic insects were exposed to both pollutants. In conclusion, insects from mercury mining sites in the BRSG are at risk.

Unidades RISC: una estrategia para evaluar riesgos de salud en la población infantil de comunidades contaminadas

[RESUMEN]. Las crisis humanitarias pueden presentarse en sitios afectados por amenazas químicas, físicas, biológicas y sociales, sobre todo cuando estas amenazas interaccionan entre sí y causan una sindemia. A fin de evitar las crisis, en estos sitios se hace necesario introducir medidas de mitigación que hemos enmarcado bajo el término de “escenarios humanitarios”. Debido a su naturaleza, la implementación de dichas acciones de intervención requiere de la conformación de grupos operativos multidisciplinarios y de una estrategia de trabajo que permita integrarlos con la comunidad afectada. En el caso de la población infantil, el grupo ope- rativo recibió el nombre de unidad de riesgos infantiles en sitios contaminados (RISC), es decir, en localidades impactadas por amenazas químicas, físicas o biológicas. La estrategia consta de las siguientes seis fases: i) planificación para el estudio y la visita al sitio; ii) participación de la comunidad para identificar amena- zas, vulnerabilidades y rutas de exposición (el camino que deben seguir los contaminantes desde su fuente hasta la población receptora), así como para el trabajo conjunto en las siguientes fases; iii) priorización de riesgos identificados mediante el monitoreo ambiental y uso de biomarcadores de exposición y efectos; iv) prevención de riesgos a través de la creación de diversas capacidades y alternativas para la prevención ante amenazas sindémicas (CAPAS); v) promoción para implementar las CAPAS mediante la comunicación de riesgos y la capacitación local; y vi) protección con medidas que incluyen propuestas de telesalud, progreso social e innovación para mejorar la cobertura sanitaria. La estrategia ha sido aplicada en diferentes contextos, en algunos de los cuales, ha sido enriquecida con el análisis del respeto de los derechos humanos.

[ABSTRACT]. Humanitarian crises can occur in places affected by chemical, physical, biological, and social threats, espe- cially when these threats interact with each other and cause a syndemic. In order to avoid crises in these places, it is necessary to introduce mitigation measures that we have framed as "humanitarian scenarios". Due to their nature, implementation of these interventions requires the creation of multidisciplinary operational groups with a work strategy that integrates them into the affected community. In the case of the child popula- tion, the operational group was called the ‘childhood risks in contaminated places’ (CRCP) unit; contaminated places meaning localities impacted by chemical, physical, or biological threats. The strategy has six phases: (i) planning the survey and site visit; (ii) community involvement in identifying threats, vulnerabilities, and routes of exposure (the path of pollutants from their source to the receiving population), and in preparing joint work for the subsequent phases; iii) prioritization of risks identified through environmental monitoring and use of bio- markers of exposure and effects; iv) risk prevention through the creation of various ‘capacities and alternatives for the prevention of syndemic threats’; (v) advocacy to implement these capacities and alternatives through risk communication and local training; and (vi) protection through measures that include telehealth, social pro- gress, and innovation to improve health coverage. The strategy has been implemented in different contexts, and in some of them it has been enriched by analysis of respect for human rights.

[RESUMO]. Crises humanitárias podem ocorrer em locais afetados por ameaças químicas, físicas, biológicas e sociais, principalmente quando essas ameaças interagem entre si e causam uma sindemia. Para evitar as crises, é necessário introduzir nesses locais medidas de mitigação que enquadramos no termo “cenários huma- nitários”. Por sua natureza, a implementação de tais ações de intervenção exige a formação de grupos operacionais multidisciplinares e de uma estratégia de trabalho que permita integrá-los à comunidade afe- tada. No caso da população infantil, o grupo operacional recebeu o nome de Unidade de Riscos Infantis em Áreas Contaminadas (na sigla em espanhol, RISC), ou seja, em locais impactados por ameaças químicas, físicas ou biológicas. A estratégia consiste nas seis fases a seguir: i) planejamento para o estudo e visita ao local; ii) participação da comunidade para identificar ameaças, vulnerabilidades e rotas de exposição (caminho que os contaminantes devem seguir desde a sua fonte até a população receptora), bem como para o trabalho conjunto nas fases seguintes; iii) priorização dos riscos identificados por meio do monitoramento ambiental e uso de biomarcadores de exposição e efeitos; iv) prevenção de riscos por meio da criação de diversas capacidades e alternativas para a prevenção diante de ameaças sindêmicas (CAPAS); v) promoção da implantação das CAPAS por meio da comunicação de riscos e capacitação local; e vi) proteção com medi- das que incluem propostas de telessaúde, progresso social e inovação para melhorar a cobertura de saúde. A estratégia foi aplicada em diferentes contextos, em alguns dos quais foi enriquecida com uma análise do respeito pelos direitos humanos.

Unidades RISC: una estrategia para evaluar riesgos de salud en la población infantil de comunidades contaminadas / CRCP units: a strategy to assess health risks in children in contaminated communities / Unidades RISC: uma estratégia para avaliar os riscos de saúde na população infantil de comunidades contaminadas

RESUMEN Las crisis humanitarias pueden presentarse en sitios afectados por amenazas químicas, físicas, biológicas y sociales, sobre todo cuando estas amenazas interaccionan entre sí y causan una sindemia. A fin de evitar las crisis, en estos sitios se hace necesario introducir medidas de mitigación que hemos enmarcado bajo el término de "escenarios humanitarios". Debido a su naturaleza, la implementación de dichas acciones de intervención requiere de la conformación de grupos operativos multidisciplinarios y de una estrategia de trabajo que permita integrarlos con la comunidad afectada. En el caso de la población infantil, el grupo operativo recibió el nombre de unidad de riesgos infantiles en sitios contaminados (RISC), es decir, en localidades impactadas por amenazas químicas, físicas o biológicas. La estrategia consta de las siguientes seis fases: i) planificación para el estudio y la visita al sitio; ii) participación de la comunidad para identificar amenazas, vulnerabilidades y rutas de exposición (el camino que deben seguir los contaminantes desde su fuente hasta la población receptora), así como para el trabajo conjunto en las siguientes fases; iii) priorización de riesgos identificados mediante el monitoreo ambiental y uso de biomarcadores de exposición y efectos; iv) prevención de riesgos a través de la creación de diversas capacidades y alternativas para la prevención ante amenazas sindémicas (CAPAS); v) promoción para implementar las CAPAS mediante la comunicación de riesgos y la capacitación local; y vi) protección con medidas que incluyen propuestas de telesalud, progreso social e innovación para mejorar la cobertura sanitaria. La estrategia ha sido aplicada en diferentes contextos, en algunos de los cuales, ha sido enriquecida con el análisis del respeto de los derechos humanos.

ABSTRACT Humanitarian crises can occur in places affected by chemical, physical, biological, and social threats, especially when these threats interact with each other and cause a syndemic. In order to avoid crises in these places, it is necessary to introduce mitigation measures that we have framed as "humanitarian scenarios". Due to their nature, implementation of these interventions requires the creation of multidisciplinary operational groups with a work strategy that integrates them into the affected community. In the case of the child population, the operational group was called the 'childhood risks in contaminated places' (CRCP) unit; contaminated places meaning localities impacted by chemical, physical, or biological threats. The strategy has six phases: (i) planning the survey and site visit; (ii) community involvement in identifying threats, vulnerabilities, and routes of exposure (the path of pollutants from their source to the receiving population), and in preparing joint work for the subsequent phases; iii) prioritization of risks identified through environmental monitoring and use of biomarkers of exposure and effects; iv) risk prevention through the creation of various 'capacities and alternatives for the prevention of syndemic threats'; (v) advocacy to implement these capacities and alternatives through risk communication and local training; and (vi) protection through measures that include telehealth, social progress, and innovation to improve health coverage. The strategy has been implemented in different contexts, and in some of them it has been enriched by analysis of respect for human rights.

RESUMO Crises humanitárias podem ocorrer em locais afetados por ameaças químicas, físicas, biológicas e sociais, principalmente quando essas ameaças interagem entre si e causam uma sindemia. Para evitar as crises, é necessário introduzir nesses locais medidas de mitigação que enquadramos no termo "cenários humanitários". Por sua natureza, a implementação de tais ações de intervenção exige a formação de grupos operacionais multidisciplinares e de uma estratégia de trabalho que permita integrá-los à comunidade afetada. No caso da população infantil, o grupo operacional recebeu o nome de Unidade de Riscos Infantis em Áreas Contaminadas (na sigla em espanhol, RISC), ou seja, em locais impactados por ameaças químicas, físicas ou biológicas. A estratégia consiste nas seis fases a seguir: i) planejamento para o estudo e visita ao local; ii) participação da comunidade para identificar ameaças, vulnerabilidades e rotas de exposição (caminho que os contaminantes devem seguir desde a sua fonte até a população receptora), bem como para o trabalho conjunto nas fases seguintes; iii) priorização dos riscos identificados por meio do monitoramento ambiental e uso de biomarcadores de exposição e efeitos; iv) prevenção de riscos por meio da criação de diversas capacidades e alternativas para a prevenção diante de ameaças sindêmicas (CAPAS); v) promoção da implantação das CAPAS por meio da comunicação de riscos e capacitação local; e vi) proteção com medidas que incluem propostas de telessaúde, progresso social e inovação para melhorar a cobertura de saúde. A estratégia foi aplicada em diferentes contextos, em alguns dos quais foi enriquecida com uma análise do respeito pelos direitos humanos.

Evaluation of cytokines in exhaled breath condensate in an occupationally exposed population to pneumotoxic pollutants.

The quarrying is considered a precarious occupation with high toxicity, is an informal economic activity that employs low technology, limited protection, and poses a risk to workers and their families. In quarrying, silica dust is generated and there is also occupational exposure to significant mixtures of pneumotoxic pollutants, including mineral dust (crystalline silica, carbon or cement, polycyclic aromatic hydrocarbons (PAHs), solvents, and others, which are aggravated by the lack of use of protective equipment, causing irreversible damage to the worker's respiratory health. Thus, the objective of this work focused on the evaluation of the respiratory health of artisan stonemasons in San Luis Potosí, Mexico through the study of exhaled breath condensate (EBC) (pH, pro-inflammatory cytokines) as well as the study of the exposure to pollutants present in the work area (PAHs, toluene, and 2.5 µm particulate matter) through biomarkers of exposure (hippuric acid and hydroxylated metabolites of PAHs). The results show the presence of crystalline SiO2 in 100% of the samples analyzed; the PM2.5 concentrations were 5 to 10 times the permitted levels. Regarding exposure to PAHs, all the stonemasons presented urine concentrations of at least 5 of the OH-PAHs evaluated; 9-OH-FLU occurred at higher concentrations of 171.2 (122.7-279.4) µg L-1; hippuric acid, which was present in 100% of the workers evaluated in concentrations of 283.4 (27.72-1119) mg L-1, 100% of which were above the values established for occupational scenarios. The pH values obtained for the EBC samples were presented at an average of 7.07 (6.33-7.66). Pro-inflammatory cytokines were present in 86.1% of the study population. The cytokine that was found in higher concentrations was IL-2, with a mean of 178.01 pg mL-1 and 3124.01 pg mL-1 for the pH < 7 and pH > 7 groups, respectively. Some correlations between the cytokines and the exposure biomarkers were presented. Stonemasons are highly exposed to pneumotoxic pollutants and markers of inflammation at the pulmonary level; in addition, a high risk of developing silicosis. Quarrying should be addressed as a carcinogenic activity, which would imply the design of monitoring and control strategies for these pollutants that our country currently lacks, particularly in precarious occupations. It is necessary to develop strategies to protect the health of precarious workers.

A preliminary study on health impacts of Mexican mercury mining workers in a context of precarious employment.

Mercury mining is one of the main sources of mercury (Hg) release into the environment, causing serious impacts on human health and the environment. Workers in these mines are employed informally and precariously and therefore lack labor rights such as social security. The objective of the study is to make visible the exposure to environmental contaminants and the health of workers in mercury mines. An environmental assessment was conducted to determine workers' exposure to contaminants; urine samples were obtained to measure exposure to mercury and arsenic, and blood samples were obtained for lead and cadmium. Clinical parameters were also evaluated. Concentrations of Hg, As and Pb were determined in soil, 279.4 mg/kg (24.4-788.5), 14.7 mg/kg (9.5-20.3) and 1.4 mg/kg (1-2.8), respectively. The exposure results for mercury were 551 µg/g creatinine, for arsenic 50 µg/L and for lead 4.7 µg/dL. Cd-B was not found. In addition, 17.6 % of the workers had diabetes and 17.6 % had renal disorders. Principal Component Regression was performed obtaining an r2 of 0.86 for glomerular filtration rate and 0.54 for albumin creatinine ratio using clinical, occupational, and metal exposure variables. Exposure to Hg in this type of mine is not exclusive, so there is a cumulative risk of chronic exposure to different environmental pollutants directly impacting the health of workers. It is necessary to implement health strategies and different work opportunities for these workers.

Assessment of biomarkers of early kidney damage and exposure to pollutants in artisanal mercury mining workers from Mexico.

Artisanal mercury mining (AMM) is an informal economic activity that employs low technology and limited protection, and poses a risk to workers and their families; due to the extraction process, these scenarios involve exposure to complex mixtures of pollutants that synergistically aggravate the health of miners and people living near the site. Although mercury is the predominant pollutant, there are others such as polycyclic aromatic hydrocarbons (PAHs), toluene, arsenic, and lead which have been classified as nephrotoxic pollutants. Therefore, the purpose of this research was to evaluate the association between exposure to a complex mixture of pollutants (mercury, lead, arsenic, PAHs, and toluene) and kidney damage in artisanal Hg mining workers through early kidney damage proteins (KIM-1, OPN, RBP-4, NGAL, and Cys-C). The results demonstrate the presence of OH-PAHs at concentrations of 9.21 (6.57-80.63) µg/L, hippuric acid as a biomarker of exposure to toluene, As and Pb (655. 1 (203.8-1231) mg/L, 24.05 (1.24-42.98) g/g creatinine, and 4.74 (2.71-8.14) g/dL, respectively), and urinary Hg (503.4 (177.9-878.7) g/g creatinine) in the study population. As well as biomarkers of kidney damage, NGAL and RPB-4 were found in 100% of the samples, KIM-1 and Cys-C in 44.1%, and OPN in 41% of the miners. Significant correlations were found between several of the evaluated pollutants and early kidney damage proteins. Our results demonstrate the application of the early kidney damage biomarkers for the assessment of damage caused by the exposure to mixtures of pollutants and, therefore, the urgent need for monitoring in AMM areas.

Holistic health risk assessment in an artisanal mercury mining region in Mexico.

Mexico is one of the world's leading mercury producers and exporters. However, mercury mining is carried out using artisanal procedures, which highly impact ecosystems. In the municipality of Pinal de Amoles, Queretaro, Mexico, artisanal mercury mining (AMM) is practiced in a region that has been categorized as a Biosphere Reserve. Therefore, a holistic health risk assessment for mercury was performed in the region, including environmental monitoring (air, water, and soil) and mercury exposure in both humans (children, women, and miners) and biota (plants, rodents, and worms). The atmospheric mercury determination was carried out using the JEROME® J405 analyzer, whereas total mercury in environmental and biological samples was determined by atomic absorption spectrophotometry/cold vapor. Results showed that mercury concentrations in the environmental and biological matrices exceeded their respective reference values. These results demonstrate the direct influence of AMM in the increasing levels of mercury in all the components of the studied ecosystem. Therefore, comprehensive intervention strategies must be implemented to reduce and prevent human health and ecological risks due to the presence of mercury. In this regard, the Minamata Convention for mercury control should include biomonitoring programs not only for humans but also for critical ecological receptors in polluted ecosystems.

Evaluation of respiratory function and biomarkers of exposure to mixtures of pollutants in brick-kilns workers from a marginalized urban area in Mexico.

Brick-kilns are polluted environments due to the use of low-quality technologies and fuels, which generates black fumes with a large number of pollutants. The objective of this research was to analyze environmental exposure and biomarkers of exposure to polycyclic aromatic hydrocarbons, metals, and respiratory health in brickmakers to assess the baseline state of contamination in a brick-kiln area of San Luis Potosi, Mexico. Lead was quantified in soil and particulate matter of 2.5 µm (PM2.5) and 10 µm (PM10) in brick-kiln areas. In brickmakers, lead was evaluated in whole blood and 10 hydroxylated metabolites of polycyclic aromatic hydrocarbons were determined in urine. Respiratory health was assessed by spirometry, exhaled breath condensate, and a COPD-PS questionnaire. Data association was performed by Spearman correlation. Environmental concentrations and biomarkers of exposure are presented as medians, for lead, it was 60.4 mg/kg, for PM10, it was 2663.1 µg/m3, and for PM2.5, it was 166.6 µg/m3. For blood lead, it was 1.06 µg/dL, and the summed concentration of OH-PAHs in urine was 16.1 µg/L. Spirometry values were 2.8 ± 0.6 L and 2.9 ± 1.3 L/s FEV1 and FEV 25-75 respectively. The correlation results indicate that the older the age of the workers is and the extensive period they have been working, their lung function is affected the most. The health vulnerability present in these occupational activities is high, so it is necessary to make visible, address these economic activities in Mexico, and apply surveillance systems based on the health of the worker.

Health Sentinel: A mobile crowdsourcing platform for self-reported surveys provides early detection of COVID-19 clusters in San Luis Potosí, Mexico.

BACKGROUND: The Health Sentinel (Centinela de la Salud, CDS), a mobile crowdsourcing platform that includes the CDS app, was deployed to assess its utility as a tool for COVID-19 surveillance in San Luis Potosí, Mexico. METHODS: The CDS app allowed anonymized individual surveys of demographic features and COVID-19 risk of transmission and exacerbation factors from users of the San Luis Potosí Metropolitan Area (SLPMA). The platform's data processing pipeline computed and geolocalized the risk index of each user and enabled the analysis of the variables and their association. Point process analysis identified geographic clustering patterns of users at risk and these were compared with the patterns of COVID-19 cases confirmed by the State Health Services. RESULTS: A total of 1554 COVID-19 surveys were administered through the CDS app. Among the respondents, 50.4 % were men and 49.6 % women, with an average age of 33.5 years. Overall risk index frequencies were, in descending order: no-risk 77.8 %, low risk 10.6 %, respiratory symptoms 6.7 %, medium risk 1.4 %, high risk 2.0 %, very high risk 1.5 %. Comorbidity was the most frequent vulnerability category (32.4 %), followed by the inability to keep home lockdown (19.2 %). Statistically significant risk clusters identified at a spatial scale between 5 and 730 m coincided with those in neighborhoods containing substantial numbers of confirmed COVID-19 cases. CONCLUSIONS: The CDS platform enables the analysis of the sociodemographic features and spatial distribution of individual risk indexes of COVID-19 transmission and exacerbation. It is a useful epidemiological surveillance and early detection tool because it identifies statistically significant and consistent risk clusters in neighborhoods with a substantial number of confirmed COVID-19 cases.

Comparative analysis of chemical breath-prints through olfactory technology for the discrimination between SARS-CoV-2 infected patients and controls.

BACKGROUND: We identified a global chemical pattern of volatile organic compounds in exhaled breath capable of discriminating between COVID-19 patients and controls (without infection) using an electronic nose. METHODS: The study focused on 42 SARS-CoV-2 RT-qPCR positive subjects as well as 42 negative subjects. Principal component analysis indicated a separation of the study groups and provides a cumulative percentage of explanation of the variation of 98.3%. RESULTS: The canonical analysis of principal coordinates model shows a separation by the first canonical axis CAP1 (r2 = 0.939 and 95.23% of correct classification rate), the cut-off point of 0.0089; 100% sensitivity (CI 95%:91.5-100%) and 97.6% specificity (CI 95%:87.4-99.9%). The predictive model usefulness was tested on 30 open population subjects without prior knowledge of SARS-CoV-2 RT-qPCR status. Of these 3 subjects exhibited COVID-19 suggestive breath profiles, all asymptomatic at the time, two of which were later shown to be SARS-CoV-2 RT-qPCR positive. An additional subject had a borderline breath profile and SARS-CoV-2 RT-qPCR positive. The remaining 27 subjects exhibited healthy breath profiles as well as SARS-CoV-2 RT-qPCR test results. CONCLUSIONS: In all, the use of olfactory technologies in communities with high transmission rates as well as in resource-limited settings where targeted sampling is not viable represents a practical COVID-19 screening approach capable of promptly identifying COVID-19 suspect patients and providing useful epidemiological information to guide community health strategies in the context of COVID-19.

Revisión del impacto del sector ladrillero sobre el ambiente y la salud humana en México / Environmental and human health effects caused by the Mexican bricks factories

Resumen: Objetivo: Describir el trabajo precario en el sector ladrillero de México, sus efectos en salud e intervenciones. Material y métodos: Se realizó una revisión sobre el sector ladrillero, así como su impacto en la salud y los estudios de exposición que se han realizado en México en bases de datos y sitios gubernamentales con restricción de idioma inglés y español. Las palabras claves utilizadas fueron "trabajo precario", "contaminación por ladrilleras", "efectos en salud" e "intervenciones". Resultados: Existen pocos trabajos que señalen la exposición ambiental y biológica en el sector ladrillero del país. Se encontraron diversas intervenciones en el sector para reducir los impactos ambientales y de salud, sin embargo, no se enfocan directamente en el trabajador y sus familias. Conclusión: Las zonas ladrilleras presentan altos niveles de contaminación. Se requiere de información que refleje la exposición a mezclas de sustancias tóxicas en trabajadores, familias y población aledaña a estas zonas.

Abstract: Objective: To describe the precarious conditions of the workers on the Mexican brick sector and their effects on health and possible intervention projects. Materials and methods: A review of databases and government sites (with English and Spanish language restrictions) was carried out to correlate the human health injury caused by the bricks factories' pollution. Exposure and health impact studies carried out in Mexico were analyzed. Keywords corresponding "precarious work", "brick pollution", "health effects" and "interventions" were used in the database search. Results: We found only a few studies that described environmental and biological effects caused by the brick sector in Mexico. Regarding intervention programs published until this year, our analysis indicates that these projects have the aim to reduce the environmental impacts but not ameliorate the health of the brick factories workers and their families. Conclusions: High levels of pollution were described in brick factories' areas. New studies are required to explore the effects of mixtures toxic substances over health workers, his families, and surrounding factories' population.

Analysis of urinary metabolites of polycyclic aromatic hydrocarbons in precarious workers of highly exposed occupational scenarios in Mexico.

Exposure to polycyclic aromatic hydrocarbons (PAHs) is a risk factor for human health. Workers are a vulnerable group due to their high exposure and therefore require special attention to mitigation measurements; however, some groups of workers are especially vulnerable, precarious workers. The objective of this research was to evaluate mixtures of hydroxylated PAHs (OH-PAHs) in precarious workers in Mexico. The following activities were evaluated: (i) brickmakers (TER), stonemasons (ESC), indigenous workers (TOC) and mercury miners (CAM). Ten OH-PAHS were analyzed: 1-hydroxynaphtalene and 2-hydroxynaphtalene; 2-,3- and 9-hydroxyfluorene; 1-,2-,3- and 4-hydroxyphenanthrene; and 1-hydroxypyrene in urine by GC-MS, chemical fingerprints of the sites were established by multivariate analysis. One hundred forty-nine precarious workers participated in the study. The populations presented total OH-PAHs concentrations of 9.20 (6.65-97.57), 14.8 (9.32-18.85), 15.7 (6.92-195.0), and 101.2 (8.02-134.4) µg/L for CAM, ESC, TER, and TOC, respectively (median (IQR)). The results of the multivariate analysis indicate that the indigenous population presented a different fingerprint compared to the three scenarios. The chemical fingerprints among the brickmakers and mercury mining population were similar. The results of the concentrations were similar and in some metabolites higher than workers in occupations classified as carcinogenic by the IARC; therefore, the control of exposure in these occupations acquires great importance and surveillance through biological monitoring of OH-PAHs should be applied to better estimate exposure in these working populations.

Evaluation of acute and chronic exposure to aflatoxin B1 in indigenous women of the Huasteca Potosina, Mexico.

Aflatoxin B1 (AFB1) is one of the most studied mycotoxins due to its high occurrence in food and its hepatotoxic, immunosuppressive, carcinogenic, childhood growth, genotoxic, mutagenic, and teratogenic effects in humans and animals. Exposure to AFB1 is reported to be both, acute and chronic; the main exposure pathway to AFB1 is through the intake of contaminated food. In Mexico, although the reports of several studies addressing the problem of aflatoxins in maize and other foods, the evidence has been centered on exposure to AFB1 and to the quantification of the Aflatoxins themselves, but there is null evidence about genotoxic effects of aflatoxins in vulnerable populations. Therefore, this study focused on assessing chronic AFB1 exposure through the AFB1-lys biomarker adduct and acute exposure through total AFB1-DNA adducts in women from a rural indigenous community in the Huasteca Potosina (Mexico). A hundred percent of the studied population presented total AFB1-DNA and AFB1-lys adducts in concentrations of 1.08 (0.48-1.34) µmol of adduct/mol of DNA and 2.33 (1.08-102.6) pg/mg of albumin respectively (median (min-max)). Thus, continuous monitoring and important changes in regulations are desired and recommended. The results in this study provide enough evidence to support the toxic effects that the exposure to AFB1 represents, as well as the population risk that it poses, and in the same sense, the current need to create an intervention program that directly influences the control of the sources of exposure in order to reduce it.

Revisión del impacto del sector ladrillero sobre el ambiente y la salud humana en México.

Objetivo. Describir el trabajo precario en el sector ladrillero de México, sus efectos en salud e intervenciones. Material y métodos. Se realizó una revisión sobre el sector ladrillero, así como su impacto en la salud y los estudios de exposición que se han realizado en México en bases de datos y sitios gubernamentales con restricción de idioma inglés y español. Las palabras claves utilizadas fueron "trabajo precario", "contaminación por ladrilleras", "efectos en salud" e "intervenciones". Resultados. Existen pocos trabajos que señalen la exposición ambiental y biológica en el sector ladrillero del país. Se encontraron diversas intervenciones en el sector para reducir los impactos ambientales y de salud, sin embargo, no se enfocan directamente en el trabajador y sus familias. Conclusión. Las zonas ladrilleras presentan altos niveles de contaminación. Se requiere de información que refleje la exposición a mezclas de sustancias tóxicas en trabajadores, familias y población aledaña a estas zonas.

Ultrafast gas chromatography coupled to electronic nose to identify volatile biomarkers in exhaled breath from chronic obstructive pulmonary disease patients: A pilot study.

An analytical method to identify volatile organic compounds (VOCs) in the exhaled breath from patients with a diagnosis of chronic obstructive pulmonary disease (COPD) using a ultrafast gas chromatography system equipped with an electronic nose detector (FGC eNose) has been developed. A prospective study was performed in 23 COPD patients and 33 healthy volunteers; exhalation breathing tests were performed with Tedlar bags. Each sample was analyzed by FCG eNose and the identification of VOCs was based on the Kovats index. Raw data were reduced by principal component analysis (PCA) and canonical discriminant analysis [canonical analysis of principal coordinates (CAP)]. The FCG eNose technology was able to identify 17 VOCs that distinguish COPD patients from healthy volunteers. At all stages of PCA and CAP the discrimination between groups was obvious. Chemical prints were correctly classified up to 82.2%, and were matched with 78.9% of the VOCs detected in the exhaled breath samples. Receiver operating characteristic curve analysis indicated the sensitivity and specificity to be 96% and 91%, respectively. This pilot study demonstrates that FGC eNose is a useful tool to identify VOCs as biomarkers in exhaled breath from COPD patients. Further studies should be performed to enhance the clinical relevance of this quick and ease methodology for COPD diagnosis.

Respiratory health assessment and exposure to polycyclic aromatic hydrocarbons in Mexican indigenous population.

Indoor air pollution is an important risk factor for the generation of lung diseases in developing countries. The indigenous population is particularly susceptible to be exposed to the mixture of pollutants from the biomass burning, among them, polycyclic aromatic hydrocarbons (PAHs). The objective of this study was to assess respiratory health and exposure to PAHs in indigenous populations of the Huasteca Potosina in Mexico. The urinary metabolite 1-hydroxypyrene (1-OHP) was evaluated by HPLC with fluorescence detector, the forced expiratory volume in one second (FEV1) and the FEV1/FVC ratio (forced vital capacity) by spirometry in the Teenek indigenous adult population of the communities from Tocoy (TOC), Xolol (XOL), and Tanjajnec (TAN). A total of 134 subjects participated in the study: 64 from TOC, 30 from XOL, and 40 from TAN; in all the communities, high percentages of overweight and obesity were presented (from 50 to 73%). The average hours of firewood usage per year were 281.06, 284.6, and 206.6 in TOC, XOL, and TAN, respectively. The average of the three communities of the % FEV1 post-bronchodilator was 86.1%. There were identified from 4.5 to 6.6% and from 12.5 to 15.5% of spirometric obstructive and restrictive patterns respectively, in all communities. The highest exposure levels reported as median were found in TOC (1.15 µmol/mol of creatinine) followed by TAN (0.94 µmol/mol of creatinine) and XOL (0.65 µmol/mol of creatinine). Considering the magnitude of the indigenous population exposed to pollutants from the biomass burning and the possible effects on respiratory health, it is important to design strategies that mitigate exposure and evaluate the effectiveness through biological monitoring and effects.

Environmental Health Promotion of a Contaminated Site in Mexico.

Entangled in complex ecological, sociocultural, and economic systems, current environmental health problems require integrated participatory approaches. Alpuyeca, a semi-urban, highly marginalized community in South-Central Mexico burdened by lead and polychlorinated biphenyl (PCB) contamination, dengue fever, and intestinal diseases, illustrates this. Its residents are distinctive, however, for their concerted actions in the face of environmental problems and the presence of defenders of a prehispanic worldview based on the protection of nature. This article addresses the health impacts of an integrated environmental health promotion strategy implemented through a participatory action research intervention based on qualitative and quantitative methods. Different actors, sectors, dimensions, and knowledge types were harmonized in a collaborative space created specifically for our interdisciplinary research team, community residents and local authorities. Reflections, plans and actions were developed collectively in this space with the view of finding solutions anchored in the local culture. Results included sharp reductions in blood-lead concentrations among children, in entomological indices, and in PCB contamination, as well as capacity strengthening. Medium-level community participation was achieved. This work contributes evidence that participatory environmental health research can be effective in analyzing and reducing problems in communities with multiple environmental health concerns. It complements ecohealth and environmental health literacy approaches.

Evaluation of emerging biomarkers of renal damage and exposure to aflatoxin-B1 in Mexican indigenous women: a pilot study.

Aflatoxins (AFs) are mycotoxins produced by Aspergillus parasiticus and Aspergillus flavus which frequently contaminate maize. These compounds are considered toxic, especially AFB1 which has been classified as a human carcinogen, due to its relationship with the generation of hepatocellular carcinoma. Studies in vivo, in animal models, prove that chronic consumption of AFB1 has an association with renal adverse effects, but evidence in humans is scarce. Therefore, the main objective of this research was to conduct a pilot study to evaluate the correlation between exposure to AFB1 and early-stage renal damage in indigenous women of San Luis Potosí, Mexico. Exposure to AFB1 was measured through the biomarker AFB1-lysine and renal damage through kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and cystatin-C (Cys-C). AFB1-Lys was measured by HPLC-FLD. The method was validated with a correlation coefficient of 0.99 and limit of detection and quantification of 3.5 and 4.7 pg mL-1, respectively. Levels of NGAL, KIM-1, and Cys-C were determined (median (P25-P75), 5.96 (3.16-15.91), 0.137 (0.137-0.281), and 18.49 (5.76-29.57) ng mL-1, respectively). Additionally, glomerular filtration rate (GFR) (83.3 (59.8-107.4) mL/min/1.73 m2) and serum creatinine (SCr) (0.88 (0.72-1.22) mg dL-1) were obtained. The median concentrations for AFB1-Lys were 2.08 (1.89-5.8) pg mg-1 of albumin. Statistically significant correlations between AFB1-Lys/KIM-1 (Rho = 0.498, p = 0.007) and AFB1/Cys-C (Rho = 0.431, p = 0.014) were found. Our results indicate that women are exposed to AFB1, due to the fact that the AFB1-Lys biomarker was found in a high percentage of the study population (83%). In addition, the results of exposure to AFB1 show a strong significant correlation between KIM-1 and Cys-C that may indicate the toxic renal effect. These results are alarming because of the high toxicity of this compound and require adequate intervention to reduce AFB1 exposure in these populations.

Exposure to Mixtures of Pollutants in Mexican Children from Marginalized Urban Areas.

BACKGROUND: Exposure to contaminant mixtures in developing countries is an important public health issue. Children are identified as the most susceptible group to adverse health effects due to the exposure. OBJECTIVE: The aim of this study was to conduct a screening for mixture pollutants in Mexican children in urban marginalized communities. METHODS: We analyzed children (aged 6-12 years old) who resided in four urban marginalized communities in San Luis Potosi, Mexico: i) Bellas Lomas (BEL), a site with vehicular traffic; ii) Tercera Chica (TC), a site with brick kilns; Iii) Rincon de San Jose (SJR), a site with a hazardous waste landfill; and (iv) Morales (MOR) a metallurgical zone with copper-arsenic and electrolytic zinc smelters. Polycyclic Aromatic Hydrocarbons (1-hydroxypyrene (1-OHP)), benzene (trans, trans-muconic acid (t,t-MA), manganese, arsenic and fluoride were quantified in urine and lead in blood samples. FINDINGS: Our results indicate that median exposures to manganese were 4.4, 5.2, 5.8 and 6.3 µg/L for BEL, TC, SJR and MOR, respectively. For BEL, fluoride was present at a higher concentration with 2.3 mg/L followed by MOR, TC and SJR with 1.7, 1.5 and 1.2 mg/L respectively. The highest concentrations of arsenic that were found were 11 µg/L in MOR and lead concentration was reported between 4.2 and 6.8 µg/dL, in BEL, TC and MOR. 1-OHP and t,t-MA were higher in TC (0.23 µmol/mol creatinine (cr), 429.7 µg/g cr, respectively) followed by SJR (0.09 µmol/mol cr, 427.4 µg/g cr), MOR (0.03 µmol/mol cr, 258.6 µg/g cr) and BEL (0.06 µmol/mol cr, 220.6 µg/g cr). CONCLUSION: Considering the large number of people, especially children, exposed to multiple pollutants, it is important to design effective intervention programs that reduce exposure and the resultant risk in the numerous urban marginalized communities in Mexico.