Horacio Riojas-rodríguez - Academia.edu (original) (raw)

Papers by Horacio Riojas-rodríguez

Research paper thumbnail of Uso de la variabilidad de la frecuencia cardiaca como marcador de los efectos cardiovasculares asociados con la contaminación del aire

Salud Pública de México, 2006

Use of heartrate variability as a marker of cardiovascular effects associated with air pollution.

Research paper thumbnail of Human resources training in Environmental Health in Mexico with a global vision and local depth in order to face current challenges

Revista de Salud Ambiental, 2018

Financiación: Este grupo no ha contado con ningún tipo de financiación para el desarrollo de su t... more Financiación: Este grupo no ha contado con ningún tipo de financiación para el desarrollo de su trabajo. Declaración de conflicto de intereses: Los autores declaran que no existen conflictos de intereses que hayan influido en la realización y la preparación de este trabajo. Declaraciones de autoría: Todos los autores contribuyeron al diseño del estudio y la redacción del artículo. Asimismo, todos los autores aprobaron la versión final.

Research paper thumbnail of Formación de recursos humanos en Salud Ambiental en México con visión global y profundidad local para enfrentar los retos actuales

Revista de Salud Ambiental, 2018

Mexico y la region de Latinoamerica enfrentan enormes retos relacionados con la degradacion y con... more Mexico y la region de Latinoamerica enfrentan enormes retos relacionados con la degradacion y contaminacion ambiental y su impacto en la salud humana y en los ecosistemas, por lo que es necesario formar profesionales con vision multidisciplinaria. El Instituto Nacional de Salud Publica ha acumulado desde 1990 experiencia en la ensenanza de la salud ambiental. Originalmente, con un enfoque epidemiologico e incorporando progresivamente perspectivas mas integradoras. Por su parte la Universidad Autonoma de San Luis Potosi a partir del ano 2002 con el Programa Multidisciplinario de Posgrado en Ciencias Ambientales ha contribuido en la formacion de recursos humanos altamente especializados en el area de las ciencias ambientales. Ambas instituciones son lideres en el estudio de la Salud Ambiental y han generado informacion cientifica sobre diversas problematicas en zonas mineras, agricolas, metropolitanas, indigenas, entre otras. Sin duda, se han obtenido avances significativos en la form...

Research paper thumbnail of Household Firewood Use and the Health of Children and Women of Indian Communities in Chiapas, Mexico

International Journal of Occupational and Environmental Health, 2001

A follow-up study in two rural communities in the state of Chiapas, Mexico, compared families tha... more A follow-up study in two rural communities in the state of Chiapas, Mexico, compared families that used an improved stove for cooking with those that used traditional open-fire stoves, to assess the risks of respiratory symptoms in children and women exposed to wood smoke. 16-hour measurements showed that the concentration of particles less than 10 microm in diameter was significantly lower in households with the better stoves in the kitchen area, where children usually play, i.e., 158 microg/m3 vs 305 microg/m3 (p = 0.03). Multivariate models showed that using the better stove tended to protect against symptoms such as the common cold in children (RR 0.24; 9.5% CI 0.05, 1.02). Use of more firewood was linked to greater risks of experiencing difficulty breathing (RR 1.15; 95% CI 1.04, 1.27) and the common cold (RR 1.09; 95% CI 1.01, 1.18) in women. The use of stoves that require less wood for cooking reduces the risks of respiratory symptoms that may contribute to complicated respiratory diseases and mortality.

Research paper thumbnail of Motor alterations associated with exposure to manganese in the environment in Mexico

Science of The Total Environment, 2006

Overexposure to manganese (Mn) causes neurotoxicity (a Parkinson-like syndrome) or psychiatric da... more Overexposure to manganese (Mn) causes neurotoxicity (a Parkinson-like syndrome) or psychiatric damage ("manganese madness"). Several studies have shown alterations to motor and neural behavior associated with exposure to Mn in the workplace. However, there are few studies on the effects of environmental exposure of whole populations. We studied the risk of motor alterations in people living in a mining district in Mexico. We studied 288 individual people (168 women and 120 men) from eight communities at various distances from manganese extraction or processing facilities in the district of Molango. We measured manganese concentrations in airborne particles, water, soil and crops and evaluated the possible routes of Mn exposure. We also took samples of people's blood and determined their concentrations of Mn and lead (Pb). We used "Esquema de Diagnóstico Neuropsicológico" Ardila and Ostrosky-Solís's neuropsychological battery to evaluate motor functions. Concentrations of Mn in drinking water and maize grain were less than detection limits at most sampling sites. Manganese extractable by DTPA in soils ranged between 6 and 280 mg kg(-1) and means were largest close to Mn extraction or processing facilities. Air Mn concentration ranged between 0.003 and 5.86 microg/m(3); the mean value was 0.42 microg/m(3) and median was 0.10 microg/m(3), the average value (geometric mean) resulted to be 0.13 microg/m(3). Mean blood manganese concentration was 10.16 microg/l, and geometric mean 9.44 microg/l, ranged between 5.0 and 31.0 mcrog/l. We found no association between concentrations of Mn in blood and motor tests. There was a statistically significant association between Mn concentrations in air and motor tests that assessed the coordination of two movements (OR 3.69; 95% CI 0.9, 15.13) and position changes in hand movements (OR 3.09; CI 95% 1.07, 8.92). An association with tests evaluating conflictive reactions (task that explores verbal regulations of movements) was also found (OR 2.30; CI 95% 1.00, 5.28). It seems from our results that people living close to the manganese mines and processing plants suffer from an incipient motor deficit, as a result of their inhaling manganese-rich dust.

Research paper thumbnail of Persistent Organic Pollutants in Serum and Breast Milk of Fertile-Aged Women

Revista Internacional de Contaminación Ambiental, 2019

Persistent organic pollutants (POPs) can be transferred through the placenta and breast milk to t... more Persistent organic pollutants (POPs) can be transferred through the placenta and breast milk to the developing human offspring, carrying immediate and delayed health risks. We sought to evaluate potential levels of exposure to POPs during critical windows of development: pregnancy and lactation. Two cross-sectional studies were carried out in villages of the states of Sonora and Sinaloa in Mexico, where high levels of POPs have been detected through environmental and human monitoring. POPs were measured in the serum of 60 fertile-aged women in the first study. Breast milk POPs concentrations were measured in a pooled sample of 50 women in the second study. This may be the first study in Mexico to report breast milk dioxins' and furans' concentrations. The most commonly detected POPs in serum were: pentachloroanisole (71 %), PCB 205 (43 %), tetrachlorobenzenes (17-33 %), p,p'DDE (21 %), and toxic lindane by-products α-HCH or β-HCH (15 %). Congeners of furans and dioxins with the highest concentrations in milk were 2,3,4,7,8-PeCDF (3.42 pg/g) and OCDD (33.0 pg/g), respectively. The ∑ PCDD/Fs found in this study was lower than in other studies. Both serum and milk samples of fertile-aged women suggest that p,p'DDE and PCB 180 are prevalent local POPs, among others, that may reach developing embryos and infants via the placenta and lactation. These results can serve as a starting point to determine potential levels of exposure to POPs in the most vulnerable stages of life and to evaluate concentration trends in the process of eliminating these compounds.

Research paper thumbnail of Exposure to PM2.5 and Obesity Prevalence in the Greater Mexico City Area

International Journal of Environmental Research and Public Health, 2021

Exposure to PM2.5 has been associated with the prevalence of obesity. In the Greater Mexico City ... more Exposure to PM2.5 has been associated with the prevalence of obesity. In the Greater Mexico City Area (GMCA), both are ranked among the highest in the world. Our aim was to analyze this association in children, adolescents, and adults in the GMCA. We used data from the 2006 and 2012 Mexican National Surveys of Health and Nutrition (ENSANUT). Participants’ past-year exposure to ambient PM2.5 was assessed using land use terms and satellite-derived aerosol optical depth estimates; weight and height were measured. We used survey-adjusted logistic regression models to estimate the odds ratios (ORs) of obesity (vs. normal-overweight) for every 10 µg/m3 increase in annual PM2.5 exposure for children, adolescents, and adults. Using a meta-analysis approach, we estimated the overall odds of obesity. We analyzed data representing 19.3 million and 20.9 million GMCA individuals from ENSANUT 2006 and 2012, respectively. The overall pooled estimate between PM2.5 exposure and obesity was OR = 1.96...

Research paper thumbnail of Asociación entre mortalidad por Covid-19 y contaminación atmosférica en ciudades mexicanas

Salud Pública de México, 2021

Objetivo. Analizar la asociación entre la exposición crónica a contaminantes atmosféricos y la ta... more Objetivo. Analizar la asociación entre la exposición crónica a contaminantes atmosféricos y la tasa de mortalidad por Covid-19 en ciudades mexicanas. Material y métodos. Estudio ecológico en 25 ciudades mexicanas utilizando el reporte de casos diarios de muertes por Covid-19 (febrero a junio 2020) y datos validados de contaminantes atmosféricos, considerando concentraciones promedio en cada ciudad en el último año. Se utilizaron modelos de regresión Poisson, con modelos aditivos generalizados y variables de ajuste. Resultados. Se encontró un incremento significativo de 3.5% (IC95% 2.3-4.7) en la tasa de mortalidad por Covid-19 por incremento de 1μg/m3 de NO2. La asociación con PM2.5 fue no significativa, con un incremento de 1.8% por cada μg/ m3. Conclusiones. Los resultados sugieren una asociación entre la mortalidad por Covid-19 y la exposición a NO2. Esta primera aproximación del riesgo asociado con la contami­nación del aire requiere de análisis más precisos, pero es consistente...

Research paper thumbnail of Modeling Spatial Risk of Diarrheal Disease Associated with Household Proximity to Untreated Wastewater Used for Irrigation in the Mezquital Valley, Mexico

Environmental Health Perspectives, 2020

BACKGROUND: Reusing wastewater for irrigation is a longstanding practice that enhances crop yield... more BACKGROUND: Reusing wastewater for irrigation is a longstanding practice that enhances crop yields and improves climate resilience. Without treatment, however, wastewater contains harmful pathogens and chemicals. Reuse of untreated wastewater has been shown to be harmful to the health of nearby communities, but the routes of exposure are unknown and do not appear to be occupational. Some routes occur throughout entire communities, such as food contamination. Other routes may be spatially dependent, such as spread by domestic animals or through aerosolization. OBJECTIVES: To examine whether those wastewater exposure routes with a spatial dependency affect health, we estimated the risks of diarrheal disease in children under age 5 associated with living near wastewater canals, while adjusting for potential individual-and household-level confounders. METHODS: We conducted three surveys over 1 y in the Mezquital Valley, Mexico, to measure diarrhea in children. The distance between each participating household and a wastewater canal was measured using GPS coordinates. The association between proximity and diarrhea was estimated with a multilevel logistic regression model accounting for spatial autocorrelation. RESULTS: A total of 564 households completed one to three surveys, resulting in 1,856 survey observations of 646 children. Children living 100 m from a canal had 45% lower odds of diarrhea than those living within 10 m of a canal, and children living 1000 m away had 70% lower odds of diarrhea [100 m vs. 10 m adjusted odds ratio ðORÞ = 0:55, 95% credible interval (CI): 0.33, 0.91; 1000 m vs. 10 m adjusted OR = 0:30, 95% CI: 0.11, 0.82]. DISCUSSION: The estimated decline in diarrheal prevalence with household distance from a canal persisted after controlling for occupational exposure. Identifying the specific routes of exposure that drive this relationship will help identify which interventions, such as upstream treatment, can reduce health risks for entire communities where wastewater exposure occurs.

Research paper thumbnail of A follow-up study after an improved cookstove intervention in rural Mexico: Estimation of household energy use and chronic PM2.5 exposure

Environment International, 2019

The benefits of improved biomass cookstoves (ICS) depends on their adoption and sustained use. Fe... more The benefits of improved biomass cookstoves (ICS) depends on their adoption and sustained use. Few studies have documented if and how they are used more than five years after being introduced. We conducted a 9-year prospective cohort study among young rural women in the highlands of Michoacan, Mexico. Participants had received a Patsari ICS during a community trial either in 2005 or 2006. With retrospective information collected in 2012-13, we studied the households' energy use, ICS survival, and cooking practices during the follow-up period. Using an exposure model constructed with personal PM 2.5 measurements in a subsample of homes at the time of the initial trial in 2005, we estimated the exposure associated with different energy use patterns during the follow-up period. The ICS had a mean lifespan of 4 years, after which more than half of the stoves were not in use; therefore, the use of open fire increased, particularly among the indigenous communities. ICS use peak was achieved two years after the initial trial, either exclusively or combined with open fire. Yearly household energy use and other variables were used to estimate chronic air pollution exposure. Mean PM 2.5 exposure during the follow-up period ranged from 51 to 319 μg/m 3 ; the median was 102 and 146 μg/m 3 for mainly ICS and mainly open fire use, respectively. The ICS has a useful period after which it needs maintenance, repair, or replacement. Unfortunately, many programs have not afforded a follow-up component. Exposure to biomass smoke air pollutants can be reduced by using an ICS instead of the traditional open fire. Household energy strategies should ensure equitable access to clean energy options adapted to local needs and preferences with culturally appropriate technology implemented on a sustainable perspective. 2014). However, data for air pollution levels in this exposure settings are scarce and have been shown to be highly variable and dependent on a variety of factors, such as geographic location, season, household and kitchen characteristics, and more importantly, household energy use patterns (Pope et al., 2017; Quansah et al., 2017). Fine particulate matter (PM 2.5) concentration is the leading air pollution exposure indicator reported when studying adverse health effects (Burnett et al., 2014; Northcross et al., 2015).

Research paper thumbnail of Climate Change and Potential Health Effects in Mexican Children

Annals of Global Health, 2018

Climate change (CC) is the most important challenge of our time, a long-term global problem and o... more Climate change (CC) is the most important challenge of our time, a long-term global problem and one of the most serious global threats to human health in the future. CC is the expression of changes in temperature and water cycle, floods and drought events, extreme heat waves and sea level rise. Children are particularly vulnerable because they are highly sensitive to climate changes. The main environmental hazards affecting children's health are poor household drinking water quality and availability, lack access to adequate sanitary facilities, poor hygiene practices, outdoor and indoor air pollution, vector-borne diseases, chemical hazards, and unintentional injuries. Except for some unintentional injuries, these environmental hazards are associated to CC.

Research paper thumbnail of Air Pollution and Noncommunicable Diseases

Chest, 2018

Although air pollution is well-known to be harmful to the lung and airways, it can also damage mo... more Although air pollution is well-known to be harmful to the lung and airways, it can also damage most other organ systems of the body. It is estimated that about 500,000 lung cancer deaths and 1.6 million chronic obstructive pulmonary disease (COPD) deaths can be attributed to air pollution, but air pollution may also account for 19% of all cardiovascular deaths and 21% of all stroke deaths. Air pollution has been linked to other malignancies, such as bladder cancer and childhood leukemia. Lung development in childhood is stymied with exposure to air pollutants, and poor lung development in children predicts lung impairment in adults. Air pollution is associated with reduced cognitive function and increased risk of dementia. Particulate matter in the air (PM 2.5) is associated with delayed psychomotor development and lower child intelligence. Studies link air pollution with diabetes mellitus prevalence, morbidity, and mortality. Pollution affects the immune system and is associated with allergic rhinitis, allergic sensitization, and autoimmunity. It is also associated with osteoporosis and bone fractures, conjunctivitis, dry eye disease, and blepharitis, inflammatory bowel disease, increased intravascular coagulation, and decreased glomerular filtration rate. Atopic and urticarial skin disease, acne, and skin aging are linked to air pollution. Air pollution is controllable and, therefore, many of these adverse health effects can be prevented.

Research paper thumbnail of “There’s a Lot of Cancer Here…” Environmental Risk Perception and Mortality Among Women Who Live in an Industrial Corridor in Mexico. A Sequential Mixed Study

Revista Internacional de Contaminación Ambiental, 2018

The objectives of this study were to characterize the environmental risks attributed to the Quetz... more The objectives of this study were to characterize the environmental risks attributed to the Quetzalcóatl industrial corridor and to compare the records as opposed to the perceptions of increased mortality among community residents. A sequential mixed method design was used. Women in the community closest to the industrial corridor reported more respiratory disorders and more cases of cancer. They also referred to having been fearful during pregnancy because of a history in the community of premature births. From 2005 to 2007, the mortality rate for working-age women with cancer in the community closest to the corridor was significantly higher than the national rate (p < 0.05). An increase in the number of newborn deaths was observed in 1998 and 2000, with rate ratios of 5.8 (CI 3.1-6.9) and 2.9 (CI, 1.2-4.2), respectively. The integrated analysis of the qualitative and quantitative information enabled us to identify a correspondence between social perception of risk from industrial pollution and mortality registered in the study area. The experience of foul odors, the observation of increased cases of cancer and socio-cultural factors contribute to a perceived increased risk by women in the community closer to the industrial corridor. These results have implications for environmental policies in the industrial corridor, particularly with regard to risk mitigation and communication. Palabras clave: contaminación industrial, riesgo, conciencia pública, diseño mixto RESUMEN Los objetivos de este estudio fueron caracterizar los riesgos ambientales atribuidos al corredor industrial Quetzalcóatl y comparar los registros de mortalidad con las percepciones de los residentes de las comunidades. Se utilizó un diseño de método mixto secuencial. Las mujeres de la comunidad más cercana al corredor industrial reportaron más padecimientos respiratorios y más casos de cáncer. También refirieron

Research paper thumbnail of Health impact assessment of decreases in PM10 and ozone concentrations in the Mexico City Metropolitan Area. A basis for a new air quality management program

Salud Pública de México, 2014

Objective. To conduct a health impact assessment (HIA) to quantify health benefits for several PM... more Objective. To conduct a health impact assessment (HIA) to quantify health benefits for several PM and O3 air pollution reduction scenarios in the Mexico City Metropolitan Area (MCMA). Results from this HIA will contribute to the scientific support of the MCMA air quality management plan (PROAIRE) for the period 2011-2020. Materials and methods. The HIA methodology consisted of four steps: 1) selection of the air pollution reduction scenarios, 2) identification of the at-risk population and health outcomes for the 2005 baseline scenario, 3) selection of concentration-response functions and 4) estimation of health impacts. Results. Reductions of PM10 levels to 20 μg/m3 and O3 levels to 0.050ppm (98 µg/m3) would prevent 2300 and 400 annual deaths respectively. The greatest health impact was seen in the over-65 age group and in mortality due to cardiopulmonary and cardiovascular disease. Conclusion. Improved air quality in the MCMA could provide significant health benefits through focus...

Research paper thumbnail of Evaluation of the effect of an environmental management program on exposure to manganese in a mining zone in Mexico

NeuroToxicology, 2017

Background: In the state of Hidalgo, Mexico, is found the largest second deposit of Manganese (Mn... more Background: In the state of Hidalgo, Mexico, is found the largest second deposit of Manganese (Mn) in Latin America. Various studies on the sources of emission, exposure, and the effects on the health of children and adults have been conducted utilizing an ecosystem approach. Given the findings of Mn levels in air and the neurocognitive effects, an Environmental Management Program (EMP) was designed and implemented with the purpose of reducing exposure to Mn of the population, including various actions for reducing Mn emissions into the atmosphere. Objective: To evaluate the impact of the EMP on the concentrations of Mn in air, as well as the modification of exposure to Mn in the blood and hair of adult residents of the communities intervened. Methods: A quasi-experimental study was conducted in five rural communities, in which Mn concentrations were evaluated in air and in blood in the years 2002 and 2007, pre-intervention, and in 2013, postintervention. In 2003, the concentration of hair Mn among the communities was evaluated. Measurements were carried out of Particulate Matter (PM) of >10 and 2.5 mm (PM10 and PM2.5), and Mn in PM10 and PM2.5 were measured using proton-induced X-ray emissions (PIXE). The method of Difference in Differences (DID) was applied to estimate the impact of EMP on Mn concentrations in particulate matter via linear regression through multilevel models. To evaluate the effect of Mn concentrations in air over Mn concentrations in blood in both study periods in the mining communities per year (2002 and 2013), a linear regression model for each year was employed. Results: We estimated that the EMP contributed to reducing the average daily concentrations of Mn in PM10 and PM2.5 by 92 and 85%, respectively. The adjusted model did not show an effect of Mn concentrations in air over Mn concentrations in blood in both study periods. Conclusions: The results suggest that the measures implemented to reduce Mn emissions in air exerted a significant impact on the reduction of inhaled exposure in adult population.

Research paper thumbnail of Effects of climatic and social factors on dengue incidence in Mexican municipalities in the state of Veracruz

Salud Pública de México, 2017

Objective. To assess links between the social variables and longer-term El Niño-Southern Oscillat... more Objective. To assess links between the social variables and longer-term El Niño-Southern Oscillation (ENSO) related weather conditions as they relate to the week-to-week changes in dengue incidence at a regional level. Materials and methods. We collected data from 10 municipalities of the Olmeca region in México, over a 10 year period (January 1995 to December 2005). Negative binomial models with distributed lags were adjusted to look for associations between changes in the weekly incidence rate of dengue fever and climate variability. Results. Our results show that it takes approximately six weeks for sea surface temperatures (SST -34) to affect dengue incidence adjusted by weather and social variables. Conclusion. Such models could be used as early as two months in advance to provide information to decision makers about potential epidemics. Elucidating the effect of climatic variability and social variables, could assist in the development of accurate early warning systems for epi...

Research paper thumbnail of Effects of manganese exposure on visuoperception and visual memory in schoolchildren

NeuroToxicology, 2016

Conclusions: MnH is associated with alterations in visuoperception and short-term visual memory i... more Conclusions: MnH is associated with alterations in visuoperception and short-term visual memory in schoolchildren exposed to airborne Mn. Abbreviations. CNS Central Nervous System. μg/dL Micrograms per deciliter. μg/g Micrograms per gram. μg/m 3 Micrograms per cubic meter. µL Microliter. μg Micrograms. GM Geometric Mean.

Research paper thumbnail of Modeling and estimating manganese concentrations in rural households in the mining district of Molango, Mexico

Environmental Monitoring and Assessment, 2015

Airborne manganese (Mn) is considered the most hazardous route of exposure since Mn particles can... more Airborne manganese (Mn) is considered the most hazardous route of exposure since Mn particles can enter into the body through the lung and may access the brain directly through olfactory uptake, thereby bypassing homeostatic excretory mechanisms. Environmental indoor and outdoor manganese concentrations in PM2.5 were monitored in ten rural households from two communities of Hidalgo, Mexico, from 2006 to 2007. Indoor and outdoor air samples of PM2.5 were collected using MiniVol samplers, and Mn concentrations in the filters were measured using proton-induced X-ray emission (PIXE). An adjusted generalized linear mixed model was applied and then used for estimating indoor concentrations in non-monitored households. Our monitoring results showed a higher daily average concentration of indoor PM2.5 vs. outdoor PM2.5 (46.4 vs. 36.2 μg/m(3), respectively); however, manganese concentration in PM2.5 indoor and outdoor was 0.09 μg/m(3) in both sceneries. Predictor variables of indoor Mn concentration were outdoor Mn concentration (64.5% increase per 0.1 μg/m(3) change in Mn) and keeping the windows open (4.2% increase). Using these predictors, the average estimated indoor Mn concentration in PM2.5 was 0.07 μg/m(3) (SD = 0.05). Our results confirm the direct effect of outdoor Mn levels, opening house windows, and the distance to the mining chimney in indoor Mn levels in houses.

Research paper thumbnail of Effects of environmental exposure to manganese on the visuoperception and visual memory in Mexican children

Neurotoxicology and Teratology, 2015

Research paper thumbnail of Respiratory health effects of indoor air pollution

The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease, 2010

Domestic pollution is relevant to health because people spend most of their time indoors. One hal... more Domestic pollution is relevant to health because people spend most of their time indoors. One half of the world's population is exposed to high concentrations of solid fuel smoke (biomass and coal) that are produced by inefficient open fires, mainly in the rural areas of developing countries. Concentrations of particulate matter in kitchens increase to the range of milligrams per cubic meter during cooking. Solid fuel smoke possesses the majority of the toxins found in tobacco smoke and has also been associated with a variety of diseases, such as chronic obstructive pulmonary disease in women, acute respiratory infection in children and lung cancer in women (if exposed to coal smoke). Other tobacco smoke-associated diseases, such as tuberculosis, asthma, respiratory tract cancer and interstitial lung diseases, may also be associated with solid fuel smoke inhalation, but evidence is limited. As the desirable change to clean fuels is unlikely, efforts have been made to use efficie...

Research paper thumbnail of Uso de la variabilidad de la frecuencia cardiaca como marcador de los efectos cardiovasculares asociados con la contaminación del aire

Salud Pública de México, 2006

Use of heartrate variability as a marker of cardiovascular effects associated with air pollution.

Research paper thumbnail of Human resources training in Environmental Health in Mexico with a global vision and local depth in order to face current challenges

Revista de Salud Ambiental, 2018

Financiación: Este grupo no ha contado con ningún tipo de financiación para el desarrollo de su t... more Financiación: Este grupo no ha contado con ningún tipo de financiación para el desarrollo de su trabajo. Declaración de conflicto de intereses: Los autores declaran que no existen conflictos de intereses que hayan influido en la realización y la preparación de este trabajo. Declaraciones de autoría: Todos los autores contribuyeron al diseño del estudio y la redacción del artículo. Asimismo, todos los autores aprobaron la versión final.

Research paper thumbnail of Formación de recursos humanos en Salud Ambiental en México con visión global y profundidad local para enfrentar los retos actuales

Revista de Salud Ambiental, 2018

Mexico y la region de Latinoamerica enfrentan enormes retos relacionados con la degradacion y con... more Mexico y la region de Latinoamerica enfrentan enormes retos relacionados con la degradacion y contaminacion ambiental y su impacto en la salud humana y en los ecosistemas, por lo que es necesario formar profesionales con vision multidisciplinaria. El Instituto Nacional de Salud Publica ha acumulado desde 1990 experiencia en la ensenanza de la salud ambiental. Originalmente, con un enfoque epidemiologico e incorporando progresivamente perspectivas mas integradoras. Por su parte la Universidad Autonoma de San Luis Potosi a partir del ano 2002 con el Programa Multidisciplinario de Posgrado en Ciencias Ambientales ha contribuido en la formacion de recursos humanos altamente especializados en el area de las ciencias ambientales. Ambas instituciones son lideres en el estudio de la Salud Ambiental y han generado informacion cientifica sobre diversas problematicas en zonas mineras, agricolas, metropolitanas, indigenas, entre otras. Sin duda, se han obtenido avances significativos en la form...

Research paper thumbnail of Household Firewood Use and the Health of Children and Women of Indian Communities in Chiapas, Mexico

International Journal of Occupational and Environmental Health, 2001

A follow-up study in two rural communities in the state of Chiapas, Mexico, compared families tha... more A follow-up study in two rural communities in the state of Chiapas, Mexico, compared families that used an improved stove for cooking with those that used traditional open-fire stoves, to assess the risks of respiratory symptoms in children and women exposed to wood smoke. 16-hour measurements showed that the concentration of particles less than 10 microm in diameter was significantly lower in households with the better stoves in the kitchen area, where children usually play, i.e., 158 microg/m3 vs 305 microg/m3 (p = 0.03). Multivariate models showed that using the better stove tended to protect against symptoms such as the common cold in children (RR 0.24; 9.5% CI 0.05, 1.02). Use of more firewood was linked to greater risks of experiencing difficulty breathing (RR 1.15; 95% CI 1.04, 1.27) and the common cold (RR 1.09; 95% CI 1.01, 1.18) in women. The use of stoves that require less wood for cooking reduces the risks of respiratory symptoms that may contribute to complicated respiratory diseases and mortality.

Research paper thumbnail of Motor alterations associated with exposure to manganese in the environment in Mexico

Science of The Total Environment, 2006

Overexposure to manganese (Mn) causes neurotoxicity (a Parkinson-like syndrome) or psychiatric da... more Overexposure to manganese (Mn) causes neurotoxicity (a Parkinson-like syndrome) or psychiatric damage (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;manganese madness&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;). Several studies have shown alterations to motor and neural behavior associated with exposure to Mn in the workplace. However, there are few studies on the effects of environmental exposure of whole populations. We studied the risk of motor alterations in people living in a mining district in Mexico. We studied 288 individual people (168 women and 120 men) from eight communities at various distances from manganese extraction or processing facilities in the district of Molango. We measured manganese concentrations in airborne particles, water, soil and crops and evaluated the possible routes of Mn exposure. We also took samples of people&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s blood and determined their concentrations of Mn and lead (Pb). We used &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;Esquema de Diagnóstico Neuropsicológico&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; Ardila and Ostrosky-Solís&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s neuropsychological battery to evaluate motor functions. Concentrations of Mn in drinking water and maize grain were less than detection limits at most sampling sites. Manganese extractable by DTPA in soils ranged between 6 and 280 mg kg(-1) and means were largest close to Mn extraction or processing facilities. Air Mn concentration ranged between 0.003 and 5.86 microg/m(3); the mean value was 0.42 microg/m(3) and median was 0.10 microg/m(3), the average value (geometric mean) resulted to be 0.13 microg/m(3). Mean blood manganese concentration was 10.16 microg/l, and geometric mean 9.44 microg/l, ranged between 5.0 and 31.0 mcrog/l. We found no association between concentrations of Mn in blood and motor tests. There was a statistically significant association between Mn concentrations in air and motor tests that assessed the coordination of two movements (OR 3.69; 95% CI 0.9, 15.13) and position changes in hand movements (OR 3.09; CI 95% 1.07, 8.92). An association with tests evaluating conflictive reactions (task that explores verbal regulations of movements) was also found (OR 2.30; CI 95% 1.00, 5.28). It seems from our results that people living close to the manganese mines and processing plants suffer from an incipient motor deficit, as a result of their inhaling manganese-rich dust.

Research paper thumbnail of Persistent Organic Pollutants in Serum and Breast Milk of Fertile-Aged Women

Revista Internacional de Contaminación Ambiental, 2019

Persistent organic pollutants (POPs) can be transferred through the placenta and breast milk to t... more Persistent organic pollutants (POPs) can be transferred through the placenta and breast milk to the developing human offspring, carrying immediate and delayed health risks. We sought to evaluate potential levels of exposure to POPs during critical windows of development: pregnancy and lactation. Two cross-sectional studies were carried out in villages of the states of Sonora and Sinaloa in Mexico, where high levels of POPs have been detected through environmental and human monitoring. POPs were measured in the serum of 60 fertile-aged women in the first study. Breast milk POPs concentrations were measured in a pooled sample of 50 women in the second study. This may be the first study in Mexico to report breast milk dioxins' and furans' concentrations. The most commonly detected POPs in serum were: pentachloroanisole (71 %), PCB 205 (43 %), tetrachlorobenzenes (17-33 %), p,p'DDE (21 %), and toxic lindane by-products α-HCH or β-HCH (15 %). Congeners of furans and dioxins with the highest concentrations in milk were 2,3,4,7,8-PeCDF (3.42 pg/g) and OCDD (33.0 pg/g), respectively. The ∑ PCDD/Fs found in this study was lower than in other studies. Both serum and milk samples of fertile-aged women suggest that p,p'DDE and PCB 180 are prevalent local POPs, among others, that may reach developing embryos and infants via the placenta and lactation. These results can serve as a starting point to determine potential levels of exposure to POPs in the most vulnerable stages of life and to evaluate concentration trends in the process of eliminating these compounds.

Research paper thumbnail of Exposure to PM2.5 and Obesity Prevalence in the Greater Mexico City Area

International Journal of Environmental Research and Public Health, 2021

Exposure to PM2.5 has been associated with the prevalence of obesity. In the Greater Mexico City ... more Exposure to PM2.5 has been associated with the prevalence of obesity. In the Greater Mexico City Area (GMCA), both are ranked among the highest in the world. Our aim was to analyze this association in children, adolescents, and adults in the GMCA. We used data from the 2006 and 2012 Mexican National Surveys of Health and Nutrition (ENSANUT). Participants’ past-year exposure to ambient PM2.5 was assessed using land use terms and satellite-derived aerosol optical depth estimates; weight and height were measured. We used survey-adjusted logistic regression models to estimate the odds ratios (ORs) of obesity (vs. normal-overweight) for every 10 µg/m3 increase in annual PM2.5 exposure for children, adolescents, and adults. Using a meta-analysis approach, we estimated the overall odds of obesity. We analyzed data representing 19.3 million and 20.9 million GMCA individuals from ENSANUT 2006 and 2012, respectively. The overall pooled estimate between PM2.5 exposure and obesity was OR = 1.96...

Research paper thumbnail of Asociación entre mortalidad por Covid-19 y contaminación atmosférica en ciudades mexicanas

Salud Pública de México, 2021

Objetivo. Analizar la asociación entre la exposición crónica a contaminantes atmosféricos y la ta... more Objetivo. Analizar la asociación entre la exposición crónica a contaminantes atmosféricos y la tasa de mortalidad por Covid-19 en ciudades mexicanas. Material y métodos. Estudio ecológico en 25 ciudades mexicanas utilizando el reporte de casos diarios de muertes por Covid-19 (febrero a junio 2020) y datos validados de contaminantes atmosféricos, considerando concentraciones promedio en cada ciudad en el último año. Se utilizaron modelos de regresión Poisson, con modelos aditivos generalizados y variables de ajuste. Resultados. Se encontró un incremento significativo de 3.5% (IC95% 2.3-4.7) en la tasa de mortalidad por Covid-19 por incremento de 1μg/m3 de NO2. La asociación con PM2.5 fue no significativa, con un incremento de 1.8% por cada μg/ m3. Conclusiones. Los resultados sugieren una asociación entre la mortalidad por Covid-19 y la exposición a NO2. Esta primera aproximación del riesgo asociado con la contami­nación del aire requiere de análisis más precisos, pero es consistente...

Research paper thumbnail of Modeling Spatial Risk of Diarrheal Disease Associated with Household Proximity to Untreated Wastewater Used for Irrigation in the Mezquital Valley, Mexico

Environmental Health Perspectives, 2020

BACKGROUND: Reusing wastewater for irrigation is a longstanding practice that enhances crop yield... more BACKGROUND: Reusing wastewater for irrigation is a longstanding practice that enhances crop yields and improves climate resilience. Without treatment, however, wastewater contains harmful pathogens and chemicals. Reuse of untreated wastewater has been shown to be harmful to the health of nearby communities, but the routes of exposure are unknown and do not appear to be occupational. Some routes occur throughout entire communities, such as food contamination. Other routes may be spatially dependent, such as spread by domestic animals or through aerosolization. OBJECTIVES: To examine whether those wastewater exposure routes with a spatial dependency affect health, we estimated the risks of diarrheal disease in children under age 5 associated with living near wastewater canals, while adjusting for potential individual-and household-level confounders. METHODS: We conducted three surveys over 1 y in the Mezquital Valley, Mexico, to measure diarrhea in children. The distance between each participating household and a wastewater canal was measured using GPS coordinates. The association between proximity and diarrhea was estimated with a multilevel logistic regression model accounting for spatial autocorrelation. RESULTS: A total of 564 households completed one to three surveys, resulting in 1,856 survey observations of 646 children. Children living 100 m from a canal had 45% lower odds of diarrhea than those living within 10 m of a canal, and children living 1000 m away had 70% lower odds of diarrhea [100 m vs. 10 m adjusted odds ratio ðORÞ = 0:55, 95% credible interval (CI): 0.33, 0.91; 1000 m vs. 10 m adjusted OR = 0:30, 95% CI: 0.11, 0.82]. DISCUSSION: The estimated decline in diarrheal prevalence with household distance from a canal persisted after controlling for occupational exposure. Identifying the specific routes of exposure that drive this relationship will help identify which interventions, such as upstream treatment, can reduce health risks for entire communities where wastewater exposure occurs.

Research paper thumbnail of A follow-up study after an improved cookstove intervention in rural Mexico: Estimation of household energy use and chronic PM2.5 exposure

Environment International, 2019

The benefits of improved biomass cookstoves (ICS) depends on their adoption and sustained use. Fe... more The benefits of improved biomass cookstoves (ICS) depends on their adoption and sustained use. Few studies have documented if and how they are used more than five years after being introduced. We conducted a 9-year prospective cohort study among young rural women in the highlands of Michoacan, Mexico. Participants had received a Patsari ICS during a community trial either in 2005 or 2006. With retrospective information collected in 2012-13, we studied the households' energy use, ICS survival, and cooking practices during the follow-up period. Using an exposure model constructed with personal PM 2.5 measurements in a subsample of homes at the time of the initial trial in 2005, we estimated the exposure associated with different energy use patterns during the follow-up period. The ICS had a mean lifespan of 4 years, after which more than half of the stoves were not in use; therefore, the use of open fire increased, particularly among the indigenous communities. ICS use peak was achieved two years after the initial trial, either exclusively or combined with open fire. Yearly household energy use and other variables were used to estimate chronic air pollution exposure. Mean PM 2.5 exposure during the follow-up period ranged from 51 to 319 μg/m 3 ; the median was 102 and 146 μg/m 3 for mainly ICS and mainly open fire use, respectively. The ICS has a useful period after which it needs maintenance, repair, or replacement. Unfortunately, many programs have not afforded a follow-up component. Exposure to biomass smoke air pollutants can be reduced by using an ICS instead of the traditional open fire. Household energy strategies should ensure equitable access to clean energy options adapted to local needs and preferences with culturally appropriate technology implemented on a sustainable perspective. 2014). However, data for air pollution levels in this exposure settings are scarce and have been shown to be highly variable and dependent on a variety of factors, such as geographic location, season, household and kitchen characteristics, and more importantly, household energy use patterns (Pope et al., 2017; Quansah et al., 2017). Fine particulate matter (PM 2.5) concentration is the leading air pollution exposure indicator reported when studying adverse health effects (Burnett et al., 2014; Northcross et al., 2015).

Research paper thumbnail of Climate Change and Potential Health Effects in Mexican Children

Annals of Global Health, 2018

Climate change (CC) is the most important challenge of our time, a long-term global problem and o... more Climate change (CC) is the most important challenge of our time, a long-term global problem and one of the most serious global threats to human health in the future. CC is the expression of changes in temperature and water cycle, floods and drought events, extreme heat waves and sea level rise. Children are particularly vulnerable because they are highly sensitive to climate changes. The main environmental hazards affecting children's health are poor household drinking water quality and availability, lack access to adequate sanitary facilities, poor hygiene practices, outdoor and indoor air pollution, vector-borne diseases, chemical hazards, and unintentional injuries. Except for some unintentional injuries, these environmental hazards are associated to CC.

Research paper thumbnail of Air Pollution and Noncommunicable Diseases

Chest, 2018

Although air pollution is well-known to be harmful to the lung and airways, it can also damage mo... more Although air pollution is well-known to be harmful to the lung and airways, it can also damage most other organ systems of the body. It is estimated that about 500,000 lung cancer deaths and 1.6 million chronic obstructive pulmonary disease (COPD) deaths can be attributed to air pollution, but air pollution may also account for 19% of all cardiovascular deaths and 21% of all stroke deaths. Air pollution has been linked to other malignancies, such as bladder cancer and childhood leukemia. Lung development in childhood is stymied with exposure to air pollutants, and poor lung development in children predicts lung impairment in adults. Air pollution is associated with reduced cognitive function and increased risk of dementia. Particulate matter in the air (PM 2.5) is associated with delayed psychomotor development and lower child intelligence. Studies link air pollution with diabetes mellitus prevalence, morbidity, and mortality. Pollution affects the immune system and is associated with allergic rhinitis, allergic sensitization, and autoimmunity. It is also associated with osteoporosis and bone fractures, conjunctivitis, dry eye disease, and blepharitis, inflammatory bowel disease, increased intravascular coagulation, and decreased glomerular filtration rate. Atopic and urticarial skin disease, acne, and skin aging are linked to air pollution. Air pollution is controllable and, therefore, many of these adverse health effects can be prevented.

Research paper thumbnail of “There’s a Lot of Cancer Here…” Environmental Risk Perception and Mortality Among Women Who Live in an Industrial Corridor in Mexico. A Sequential Mixed Study

Revista Internacional de Contaminación Ambiental, 2018

The objectives of this study were to characterize the environmental risks attributed to the Quetz... more The objectives of this study were to characterize the environmental risks attributed to the Quetzalcóatl industrial corridor and to compare the records as opposed to the perceptions of increased mortality among community residents. A sequential mixed method design was used. Women in the community closest to the industrial corridor reported more respiratory disorders and more cases of cancer. They also referred to having been fearful during pregnancy because of a history in the community of premature births. From 2005 to 2007, the mortality rate for working-age women with cancer in the community closest to the corridor was significantly higher than the national rate (p < 0.05). An increase in the number of newborn deaths was observed in 1998 and 2000, with rate ratios of 5.8 (CI 3.1-6.9) and 2.9 (CI, 1.2-4.2), respectively. The integrated analysis of the qualitative and quantitative information enabled us to identify a correspondence between social perception of risk from industrial pollution and mortality registered in the study area. The experience of foul odors, the observation of increased cases of cancer and socio-cultural factors contribute to a perceived increased risk by women in the community closer to the industrial corridor. These results have implications for environmental policies in the industrial corridor, particularly with regard to risk mitigation and communication. Palabras clave: contaminación industrial, riesgo, conciencia pública, diseño mixto RESUMEN Los objetivos de este estudio fueron caracterizar los riesgos ambientales atribuidos al corredor industrial Quetzalcóatl y comparar los registros de mortalidad con las percepciones de los residentes de las comunidades. Se utilizó un diseño de método mixto secuencial. Las mujeres de la comunidad más cercana al corredor industrial reportaron más padecimientos respiratorios y más casos de cáncer. También refirieron

Research paper thumbnail of Health impact assessment of decreases in PM10 and ozone concentrations in the Mexico City Metropolitan Area. A basis for a new air quality management program

Salud Pública de México, 2014

Objective. To conduct a health impact assessment (HIA) to quantify health benefits for several PM... more Objective. To conduct a health impact assessment (HIA) to quantify health benefits for several PM and O3 air pollution reduction scenarios in the Mexico City Metropolitan Area (MCMA). Results from this HIA will contribute to the scientific support of the MCMA air quality management plan (PROAIRE) for the period 2011-2020. Materials and methods. The HIA methodology consisted of four steps: 1) selection of the air pollution reduction scenarios, 2) identification of the at-risk population and health outcomes for the 2005 baseline scenario, 3) selection of concentration-response functions and 4) estimation of health impacts. Results. Reductions of PM10 levels to 20 μg/m3 and O3 levels to 0.050ppm (98 µg/m3) would prevent 2300 and 400 annual deaths respectively. The greatest health impact was seen in the over-65 age group and in mortality due to cardiopulmonary and cardiovascular disease. Conclusion. Improved air quality in the MCMA could provide significant health benefits through focus...

Research paper thumbnail of Evaluation of the effect of an environmental management program on exposure to manganese in a mining zone in Mexico

NeuroToxicology, 2017

Background: In the state of Hidalgo, Mexico, is found the largest second deposit of Manganese (Mn... more Background: In the state of Hidalgo, Mexico, is found the largest second deposit of Manganese (Mn) in Latin America. Various studies on the sources of emission, exposure, and the effects on the health of children and adults have been conducted utilizing an ecosystem approach. Given the findings of Mn levels in air and the neurocognitive effects, an Environmental Management Program (EMP) was designed and implemented with the purpose of reducing exposure to Mn of the population, including various actions for reducing Mn emissions into the atmosphere. Objective: To evaluate the impact of the EMP on the concentrations of Mn in air, as well as the modification of exposure to Mn in the blood and hair of adult residents of the communities intervened. Methods: A quasi-experimental study was conducted in five rural communities, in which Mn concentrations were evaluated in air and in blood in the years 2002 and 2007, pre-intervention, and in 2013, postintervention. In 2003, the concentration of hair Mn among the communities was evaluated. Measurements were carried out of Particulate Matter (PM) of >10 and 2.5 mm (PM10 and PM2.5), and Mn in PM10 and PM2.5 were measured using proton-induced X-ray emissions (PIXE). The method of Difference in Differences (DID) was applied to estimate the impact of EMP on Mn concentrations in particulate matter via linear regression through multilevel models. To evaluate the effect of Mn concentrations in air over Mn concentrations in blood in both study periods in the mining communities per year (2002 and 2013), a linear regression model for each year was employed. Results: We estimated that the EMP contributed to reducing the average daily concentrations of Mn in PM10 and PM2.5 by 92 and 85%, respectively. The adjusted model did not show an effect of Mn concentrations in air over Mn concentrations in blood in both study periods. Conclusions: The results suggest that the measures implemented to reduce Mn emissions in air exerted a significant impact on the reduction of inhaled exposure in adult population.

Research paper thumbnail of Effects of climatic and social factors on dengue incidence in Mexican municipalities in the state of Veracruz

Salud Pública de México, 2017

Objective. To assess links between the social variables and longer-term El Niño-Southern Oscillat... more Objective. To assess links between the social variables and longer-term El Niño-Southern Oscillation (ENSO) related weather conditions as they relate to the week-to-week changes in dengue incidence at a regional level. Materials and methods. We collected data from 10 municipalities of the Olmeca region in México, over a 10 year period (January 1995 to December 2005). Negative binomial models with distributed lags were adjusted to look for associations between changes in the weekly incidence rate of dengue fever and climate variability. Results. Our results show that it takes approximately six weeks for sea surface temperatures (SST -34) to affect dengue incidence adjusted by weather and social variables. Conclusion. Such models could be used as early as two months in advance to provide information to decision makers about potential epidemics. Elucidating the effect of climatic variability and social variables, could assist in the development of accurate early warning systems for epi...

Research paper thumbnail of Effects of manganese exposure on visuoperception and visual memory in schoolchildren

NeuroToxicology, 2016

Conclusions: MnH is associated with alterations in visuoperception and short-term visual memory i... more Conclusions: MnH is associated with alterations in visuoperception and short-term visual memory in schoolchildren exposed to airborne Mn. Abbreviations. CNS Central Nervous System. μg/dL Micrograms per deciliter. μg/g Micrograms per gram. μg/m 3 Micrograms per cubic meter. µL Microliter. μg Micrograms. GM Geometric Mean.

Research paper thumbnail of Modeling and estimating manganese concentrations in rural households in the mining district of Molango, Mexico

Environmental Monitoring and Assessment, 2015

Airborne manganese (Mn) is considered the most hazardous route of exposure since Mn particles can... more Airborne manganese (Mn) is considered the most hazardous route of exposure since Mn particles can enter into the body through the lung and may access the brain directly through olfactory uptake, thereby bypassing homeostatic excretory mechanisms. Environmental indoor and outdoor manganese concentrations in PM2.5 were monitored in ten rural households from two communities of Hidalgo, Mexico, from 2006 to 2007. Indoor and outdoor air samples of PM2.5 were collected using MiniVol samplers, and Mn concentrations in the filters were measured using proton-induced X-ray emission (PIXE). An adjusted generalized linear mixed model was applied and then used for estimating indoor concentrations in non-monitored households. Our monitoring results showed a higher daily average concentration of indoor PM2.5 vs. outdoor PM2.5 (46.4 vs. 36.2 μg/m(3), respectively); however, manganese concentration in PM2.5 indoor and outdoor was 0.09 μg/m(3) in both sceneries. Predictor variables of indoor Mn concentration were outdoor Mn concentration (64.5% increase per 0.1 μg/m(3) change in Mn) and keeping the windows open (4.2% increase). Using these predictors, the average estimated indoor Mn concentration in PM2.5 was 0.07 μg/m(3) (SD = 0.05). Our results confirm the direct effect of outdoor Mn levels, opening house windows, and the distance to the mining chimney in indoor Mn levels in houses.

Research paper thumbnail of Effects of environmental exposure to manganese on the visuoperception and visual memory in Mexican children

Neurotoxicology and Teratology, 2015

Research paper thumbnail of Respiratory health effects of indoor air pollution

The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease, 2010

Domestic pollution is relevant to health because people spend most of their time indoors. One hal... more Domestic pollution is relevant to health because people spend most of their time indoors. One half of the world's population is exposed to high concentrations of solid fuel smoke (biomass and coal) that are produced by inefficient open fires, mainly in the rural areas of developing countries. Concentrations of particulate matter in kitchens increase to the range of milligrams per cubic meter during cooking. Solid fuel smoke possesses the majority of the toxins found in tobacco smoke and has also been associated with a variety of diseases, such as chronic obstructive pulmonary disease in women, acute respiratory infection in children and lung cancer in women (if exposed to coal smoke). Other tobacco smoke-associated diseases, such as tuberculosis, asthma, respiratory tract cancer and interstitial lung diseases, may also be associated with solid fuel smoke inhalation, but evidence is limited. As the desirable change to clean fuels is unlikely, efforts have been made to use efficie...