Health and Economic Impacts Assessment of O3 Exposure in Mexico.

Health effects related to exposure to air pollution such as ozone (O3) have been documented. The World Health Organization has recommended the use of the Sum of O3 Means Over 35 ppb (SOMO35) to perform Health Impact Assessments (HIA) for long-term exposure to O3. We estimated the avoidable mortality associated with long-term exposure to tropospheric O3 in 14 cities in Mexico using information for 2015. The economic valuation of avoidable deaths related to SOMO35 exposure was performed using the willingness to pay (WTP) and human capital (HC) approaches. We estimated that 627 deaths (95% uncertainty interval (UI): 227-1051) from respiratory diseases associated with the exposure to O3 would have been avoided in people over 30 years in the study area, which confirms the public health impacts of ambient air pollution. The avoidable deaths account for almost 1400 million USD under the WTP approach, whilst the HC method yielded a lost productivity estimate of 29.7 million USD due to premature deaths. Our findings represent the first evidence of the health impacts of O3 exposure in Mexico, using SOMO35 metrics.

Revisión rápida: contaminación del aire y morbimortalidad por Covid-19 / Quick review: air pollution and morbi-mortality by Covid-19

Resumen Objetivo: Analizar la evidencia sobre la relación entre la contaminación del aire y un riesgo mayor de morbimortalidad por Covid-19. Material y métodos: Se utilizó una adaptación de la metodología de revisiones rápidas de Cochrane. La búsqueda se realizó en PubMed y MedRxiv y se limitó hasta el 28 y 26 de abril, respectivamente. Los títulos y resúmenes fueron revisados por cinco investigadores que, a su vez, revisaron los textos completos de la selección final. Resultados: Se encontraron 450 manuscritos, 15 cumplieron los criterios de inclusión. La evidencia encontrada reporta que la incidencia y el riesgo de morbilidad y mortalidad por Covid-19 se incrementan con la exposición crónica y aguda a la contaminación del aire, particularmente a material particulado (PM2.5, PM10) y dióxido de nitrógeno. Conclusiones: Se requieren más estudios especialmente en ciudades latinoamericanas. Es necesario fortalecer las recomendaciones en las ciudades con mayores niveles de contaminantes y reducir sus emisiones.

Abstract Objective: To analyze the evidence on the relationship between air pollution and an increased risk of morbidity and mortality from Covid-19. Materials and methods: An adaptation of the Cochrane rapid review methodology was used. The search was performed in PubMed and MedRxiv and was limited until April 28 and 26, respectively. The titles and abstracts were reviewed by five researchers who, in turn, reviewed the full texts of the final selection. Results: 450 manuscripts were found, 15 met the inclusion criteria. The evidence reports that the incidence and risk of morbidity and mortality from Covid-19 increase with chronic and acute exposure to air pollution, particularly to particulate matter (PM2.5, PM10) and nitrogen dioxide. Conclusions: More studies are required especially in Latin American cities. It is necessary to strengthen the recommendations in cities with higher levels of pollutants and to reduce their emissions.

[Quick review: air pollution and morbi-mortalityby Covid-19.] / Revisión rápida: contaminación del aire y morbimortalidad por Covid-19.

OBJECTIVE: To analyze the evidence on the relationship between air pollution and an increased risk of morbidity and mortality from Covid-19. MATERIALS AND METHODS: An adaptation of the Cochrane rapid review methodology was used. The search was performed in PubMed and MedRxiv and was limited until April 28 and 26, respectively. The titles and abstracts were reviewed by five researchers who, in turn, reviewed the full texts of the final selection. RESULTS: 450 manuscripts were found, 15 met the inclusion criteria. The evidence reports that the incidence and risk of morbidity and mortality from Covid-19 increase with chronic and acute exposure to air pollution, particularly to particulate matter (PM2.5, P M10) and nitrogen dioxide. CONCLUSIONS: More studies are required especially in Latin American cities. It is necessary to strengthen the recommendations in cities with higher levels of pollutants and to reduce their emissions.

OBJETIVO: Analizar la evidencia sobre la relación entre la contaminación del aire y un riesgo mayor de morbimor-talidad por Covid-19. MATERIAL Y MÉTODOS: Se utilizó una adaptación de la metodología de revisiones rápidas de Cochrane. La búsqueda se realizó en PubMed y MedRxiv y se limitó hasta el 28 y 26 de abril, respectivamente. Los títu-los y resúmenes fueron revisados por cinco investigadores que, a su vez, revisaron los textos completos de la selección final. RESULTADOS: Se encontraron 450 manuscritos, 15 cumplieron los criterios de inclusión. La evidencia encon-trada reporta que la incidencia y el riesgo de morbilidad y mortalidad por Covid-19 se incrementan con la exposición crónica y aguda a la contaminación del aire, particularmente a material particulado (PM2.5, P M10) y dióxido de nitrógeno. CONCLUSIONES: Se requieren más estudios especialmente en ciudades latinoamericanas. Es necesario fortalecer las recomendaciones en las ciudades con mayores niveles de contaminantes y reducir sus emisiones.

Effect of exposure to p,p´-DDE during the first half of pregnancy in the maternal thyroid profile of female residents in a Mexican floriculture area.

BACKGROUND: Dichlorodiphenyldichloroethene (p,p´-DDE), the main metabolite of dichlorodiphenyltrichloroethane (DDT), has been associated with changes in human thyroid hormone levels. Maternal thyroid hormones are essential for adequate fetal neurodevelopment during the first half of pregnancy. OBJECTIVE: To evaluate the association between maternal p,p´-DDE concentration and the maternal thyroid profile during the first half of pregnancy. MATERIALS AND METHODS: We analyzed the information of 430 pregnant women from a Mexican floriculture area, with a gestational age ≤16 weeks. By questionnaire, we obtained sociodemographic, reproductive, and life-style, information. Serum concentrations of thyroid stimulating hormone (TSH), and total and free T3 and T4 were determined by means of Enzyme-Linked ImmunoSorbent Assay (ELISA). p,p´-DDE was analyzed by Gas Chromatography. The association between p,p´-DDE and thyroid profile was assessed through linear and logistic regression models. RESULTS: Thirty eight percent of women had p,p´-DDE levels below the Limit of Detection and 12.3% below the Limit of Quantification. Within the quantifiable range, median was 53.03ng/g. TSH >2.5 mIU/L was present in 9.3% of women; 47.7% had isolated hypothyroxinemia; 3.5% had subclinical hypothyroidism, and 5.8% had overt hypothyroidism. We observed a significant positive association between quantifiable p,p´-DDE and total T3 serum levels in comparison with those with concentrations below the Limit of Detection (ß=0.19; 95% CI=0.06, 0.34). There were no significant associations with other hormones of the thyroid profile or with clinical diagnosis. CONCLUSIONS: Our findings suggest that p,p´-DDE exposure, even at low concentrations, could disrupt thyroid homeostasis during pregnancy.