Evaluation of chemical stabilisation methods of coal-petcoke fly ash to reduce the mobility of Mo and Ni against environmental concerns.

Reducing the potential leaching of Mo and Ni from the fly ash (FA) of petroleum coke is an increasingly important issue as Asia and Europe's demand is expected to drastically intensify as continuing urbanisation and technological innovation demands ever more electricity. In the present study, we investigated coal combustion products (CCP) from a large coal-fired power station fed with a 56:44 coal/petroleum coke blend. Results revealed that leachable concentrations of Mo and Ni from FA were in the upper non-hazardous limit and in the inert limit, respectively (2003/33/EC). Whilst common prevention measures for Mo and Ni based on the adsorption capacity of boiler slag (BS), a mixture of BS: goethite, and jarosite, were considered insufficient to reduce the potential leaching of Mo into FA leachates, a novel chemical stabilisation method based on an aggregate product of portlandite and FA immobilised both Mo and Ni such that the resulting concentrations were below the limits established in the abovementioned 2003 EC Decision. Precipitation may be responsible for the fixation of Mo and Ni in the FA: portlandite aggregates as Ca(MoO4) and NiMoO4, respectively. The findings of this novel study support the use of this aggregate to reduce FA pollutants, which will be of particular interest to nations that remain largely coal/petroleum coke-dependant.

Speciation, behaviour, and fate of mercury under oxy-fuel combustion conditions.

The work presented here reports the first study in which the speciation, behaviour and fate of mercury (Hg) have been evaluated under oxy-fuel combustion at the largest oxy-Pulverised Coal Combustion (oxy-PCC) demonstration plant to date during routine operating conditions and partial exhaust flue gas re-circulation to the boiler. The effect of the CO2-rich flue gas re-circulation on Hg has also been evaluated. Results reveal that oxy-PCC operational conditions play a significant role on Hg partitioning and fate because of the continuous CO2-rich flue gas re-circulations to the boiler. Mercury escapes from the cyclone in a gaseous form as Hg(2+) (68%) and it is the prevalent form in the CO2-rich exhaust flue gas (99%) with lower proportions of Hg(0) (1.3%). The overall retention rate for gaseous Hg is around 12%; Hg(0) is more prone to be retained (95%) while Hg(2+) shows a negative efficiency capture for the whole installation. The negative Hg(2+) capture efficiencies are due to the continuous CO2-rich exhaust flue gas recirculation to the boiler with enhanced Hg contents. Calculations revealed that 44mg of Hg were re-circulated to the boiler as a result of 2183 re-circulations of CO2-rich flue gas. Especial attention must be paid to the role of the CO2-rich exhaust flue gas re-circulation to the boiler on the Hg enrichment in Fly Ashes (FAs).

[Study of infestation of dogs with Echinococcus granulosus in the province of La Rioja, Argentina]. / Estudio de infestación de caninos con Echinococcus granulosus en la provincia de La Rioja, Argentina.

This work was conducted in the province of La Rioja, located in northwestern Argentina. The aim of this study was to estimate the percentage of dog feces showing the presence of antigens of Echinococcus sp. in different regions of the province. A total of 269 samples of dried canine stool were taken, which were analyzed by the copro-ELISA technique. The most affected area was zone IV, which had 30.5% of positive samples. Zone I corresponding to the Capital Department of the province had 12% of positivity. In other areas, the percentages ranged between 11.4% and 14.8%. This is the first study in the province of La Rioja on the existence of this disease in dogs. The lack of control strategies has allowed the spread of echinococcosis.

The potential leaching and mobilization of trace elements from FGD-gypsum of a coal-fired power plant under water re-circulation conditions.

Experimental and geochemical modelling studies were carried out to identify mineral and solid phases containing major, minor, and trace elements and the mechanism of the retention of these elements in Flue Gas Desulphurisation (FGD)-gypsum samples from a coal-fired power plant under filtered water recirculation to the scrubber and forced oxidation conditions. The role of the pH and related environmental factors on the mobility of Li, Ni, Zn, As, Se, Mo, and U from FGD-gypsums for a comprehensive assessment of element leaching behaviour were also carried out. Results show that the extraction rate of the studied elements generally increases with decreasing the pH value of the FGD-gypsum leachates. The increase of the mobility of elements such as U, Se, and As in the FGD-gypsum entails the modification of their aqueous speciation in the leachates; UO2SO4, H2Se, and HAsO2 are the aqueous complexes with the highest activities under acidic conditions. The speciation of Zn, Li, and Ni is not affected in spite of pH changes; these elements occur as free cations and associated to SO4(2) in the FGD-gypsum leachates. The mobility of Cu and Mo decreases by decreasing the pH of the FGD-gypsum leachates, which might be associated to the precipitation of CuSe2 and MoSe2, respectively. Time-of-Flight mass spectrometry of the solid phase combined with geochemical modelling of the aqueous phase has proved useful in understanding the mobility and geochemical behaviour of elements and their partitioning into FGD-gypsum samples.

Effects of road dust suppressants on PM levels in a Mediterranean urban area.

The abatement of road dust emissions is currently a major challenge for sustainable transportation, causing exceedances of limits on particulate matter (PM) and high population exposures to mineral dust and metals. Mitigation measures have been proposed such as improved street cleaning and the use of dust suppressants. This study evaluated, for the first time, the effectiveness of calcium-magnesium acetate (CMA) and MgCl2 in reducing road dust emissions in a Mediterranean city. During a two-month campaign, a typical urban road in the city of Barcelona was sprayed, and changes in PMx levels and components were monitored at four traffic sites and one background monitoring sites. The integrated results indicate no statistically significant effectiveness of dust suppressants on PM10 and PM2.5-10 levels. Episodic reductions of Al, K, Mg, Cr, Li, Cu, and Zn were observed during CMA applications, but they were not systematically statistically significant over different stations and spreading days. MgCl2 days showed lower PM10 mean concentrations, but these reductions were not statistically significant and were not supported by significant drops in mineral and brake-wear metals. Based on our literature review, it can be postulated that the higher the road dust loading, the higher the dust suppressant effectiveness.

Assessment of Metal Impurity Partitioning and Speciation in Mineral Carbonation Processes Using FGD-Gypsum from Coal-Fired Power Plants under Distinct Operating Conditions.

The sequestration of carbon dioxide (CO2) stands as a profoundly pivotal environmental challenge, given its potential to directly contribute to the advancement of environmental, societal, and economic objectives across a multitude of nations. In the present study, we have conducted an evaluation of the metal impurity partitioning and speciation in mineral carbonation processes conducted in laboratory using flue gas desulfurization (FGD) gypsums originating from both Spanish and two Chinese coal-fired power plants, each subject to distinct fuel sources and FGD operational conditions. Of the three resultant carbonation products, two exhibited CaCO3 content in the range of 81-83%, while the third registered 76.9% CaCO3 content-a variance attributed to the occurrence of metallic impurities within the initial FGD-gypsum. The partitioning and speciation of metal impurities at all stages of CO2 conversion have enabled us to proffer four potential reaction mechanisms governing carbonation efficiency: (i) conversion of metal sulfates to metal carbonate complexes, (ii) transformation of transferable elements into metal oxides and oxyhydroxide complexes, (iii) transformation of metal sulfates into diverse metal complexes, and (iv) diverse pathways of elemental transformation. Metal impurities present in FGD-gypsum lead to the formation of complexes between As and metals, thereby affecting their activity. Higher Ca/Mn, Ca/Fe, and Ca/Al ratios in one FGD-gypsum slurry enhance Ca3(AsO4)2·8H2O activity, while in another, excess Ca facilitates Mn3(AsO4)2·8H2O formation during carbonation, with coprecipitation retaining As in carbonation products. The occurrence of metallic contaminants in FGD-gypsums may exert a substantial influence on the effectiveness of CO2 conversion, thereby impacting the feasibility of using resultant carbonation products, with potential implications for environmental leaching and diminished reusability prospects.

[Cases of COVID-19 in relation to environmental parameters in five departments of Catamarca province, Argentina]. / Casos de COVID-19 en relación con parámetros ambientales en cinco departamentos de la provincia de Catamarca, Argentina.

INTRODUCTION: The aim of the study was to investigate the relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments of the province of Catamarca, Argentina. METHODS: The departments Capital, Andalgalá, Paclín, Ambato and Tinogasta, Catamarca, Argentina, were studied. Between April 2021 and April 2022 variables analyzed were: number of COVID-19 cases, temperature, and percentage of environmental humidity. The correlation of variables was analyzed by the coefficient of Spearman. RESULTS: The temperature with the numbers of COVID-19 cases show inverse correlation values that ranged between -0.56 and -0.34. The humidity percentages show a slightly positive relationship only for Capital and Andalgalá, with values of 0.34 and 0.40 with the number of cases. CONCLUSION: The results showed a relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments in the province of Catamarca.

Introducción: El objetivo del trabajo fue estudiar la relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca. Métodos: Los departamentos estudiados fueron Capital, Andalgalá, Paclín, Ambato y Tinogasta, Catamarca, Argentina. Las variables número de casos COVID-19, temperatura y porcentaje de humedad ambiental fueron obtenidos entre abril de 2021 y abril de 2022. La correlación de variables se analizó mediante el coeficiente de Spearman. Resultados: La temperatura, en relación con los nú- meros de casos por COVID-19 mostró valores de correlación inversa que oscilaron entre -0.56 y -0.34. El porcentaje de humedad, indicó una relación levemente positiva con el número de casos solo para Capital y Andalgalá con valores de 0.34 y 0.40. Conclusión: Los resultados muestran una relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca.

Characterizing Meat- and Milk/Dairy-like Vegetarian Foods and Their Counterparts Based on Nutrient Profiling and Food Labels.

Vegetarian foods are plant-based (PB) foods, often perceived as healthier foods than animal-based (AB) foods. The objective of this study was to analyze the nutritional quality of a set of PB foods (meat, milk and dairy products) marketed in Spain, and to compare their nutrient profiles with respect to some AB counterparts. Nutritional information per 100 g or mL, ingredients, and nutritional declarations, as well as the Nutri-Score, NOVA, and Eco-Score of each food were collected from Open Food Facts. Differences in the nutrient compositions between PB foods and their counterparts, and between the different groups of PB foods, were assessed at a 5% significance level. A total of 544 PB foods and 373 AB foods were identified. Overall, PB foods had a higher median content of fiber and carbohydrates, but a lower amount of proteins (except PB "meat" analogues: 14 g) and saturated fats (except PB "cheese alternatives": 12.5 g), than the AB counterparts (p < 0.05). PB "milk alternatives", particularly oat "milk", showed a higher median content of total carbohydrates (8 g) and sugars (5.5 g) compared to cow milks (4.7 g carbohydrates/sugars, on average; p < 0.001). PB "meat alternatives" also had a significantly higher value of carbohydrates (9 g) than AB meats (2 g, on average; p < 0.001). PB foods were mostly classified as Nutri-Score A and B (86%). However, more than half of them were of NOVA groups 3 and 4. Thus, there is a great diversity of PB meat and milk/dairy product alternatives on the Spanish market. Despite being products of good nutritional quality compared to AB foods, they also carry drawbacks that could have an impact on nutritional health.

Unusual speciation and retention of Hg at a coal-fired power plant.

An unusual and different speciation of Hg in the outgoing gaseous stream of the flue gas desulfurization (OUT-FGD) system was revealed at two Spanish power plants (PP1 and PP2) equipped with a forced oxidation wet FGD system with water recirculation to the scrubber. At PP1 and PP2, a high proportion of Hg escapes from the electrostatic precipitator in gaseous form, Hg(2+) (75-86%) being the species that enters the FGD. At PP1 Hg(0) (71%) was the prevalent Hg OUT-FGD species, whereas at PP2 Hg(2+) was the prevalent Hg OUT-FGD species in 2007 (66%) and 2008 (87%). The unusual speciation of gaseous Hg OUT-FGD and the different Hg retentions between 2007 and 2008 at PP2 were attributable to the evaporation of HgCl(2) particles from the aqueous phase of gypsum slurry in the OUT-FGD gas and the Al additive used at PP2, respectively. The Al additive induced the retention of Hg as HgS in the 2007 FGD gypsum, thus reducing gaseous emissions of Hg in the OUT-FGD gas.

Chemical Speciation and Leaching Behavior of Hazardous Trace Elements in Coal Combustion Products from Coal-Fired Power Stations in China.

This paper reports on the chemical speciation and leaching behavior of a selected group of hazardous trace pollutants in lignite and lignite-petcoke blend co-combustion products from three power stations in China. The evaluation of speciation results showed that, during combustion, oxidizable elements, mainly As and Mo, bound to organic matter and sulfides in coals were mostly transferred to easily water-soluble forms or to slightly acidic states in the ashes. This manner was the most readily bioavailable condition for such an environment. The evaluation of the leaching results shows that the use of petroleum coke as co-fuel has an impact on the ash composition and on the leaching behavior of some inorganic trace pollutants such as Mo and V. The leaching results compared to the European waste acceptance criteria for landfills reveal that the Mo and As' leaching yield brand the coal combustion products as materials that necessitate preventative measures to reduce their potential leaching. Future work will be focused on the application of our novel chemical stabilization method to these coal ashes to reduce the mobility of elements such as Mo and As, and other potentially leachable elements, and on the use of the resulting ash with aggregate products as a substitute for concrete production.

Study of boron behaviour in two Spanish coal combustion power plants.

A full-scale field study was carried out at two Spanish coal-fired power plants equipped with electrostatic precipitator (ESP) and wet flue gas desulfurisation (FGD) systems to investigate the distribution of boron in coals, solid by-products, wastewater streams and flue gases. The results were obtained from the simultaneous sampling of solid, liquid and gaseous streams and their subsequent analysis in two different laboratories for purposes of comparison. Although the final aim of this study was to evaluate the partitioning of boron in a (co-)combustion power plant, special attention was paid to the analytical procedure for boron determination. A sample preparation procedure was optimised for coal and combustion by-products to overcome some specific shortcomings of the currently used acid digestion methods. In addition boron mass balances and removal efficiencies in ESP and FGD devices were calculated. Mass balance closures between 83 and 149% were obtained. During coal combustion, 95% of the incoming boron was collected in the fly ashes. The use of petroleum coke as co-combustible produced a decrease in the removal efficiency of the ESP (87%). Nevertheless, more than 90% of the remaining gaseous boron was eliminated via the FGD in the wastewater discharged from the scrubber, thereby causing environmental problems.

Geochemistry and oxidative potential of the respirable fraction of powdered mined Chinese coals.

This study evaluates geochemical and oxidative potential (OP) properties of the respirable (finer than 4 µm) fractions of 22 powdered coal samples from channel profiles (CP4) in Chinese mined coals. The CP4 fractions extracted from milled samples of 22 different coals were mineralogically and geochemically analysed and the relationships with the OP evaluated. The evaluation between CP4/CP demonstrated that CP4 increased concentrations of anatase, Cs, W, Zn and Zr, whereas sulphates, Fe, S, Mo, Mn, Hf and Ge decreased their CP4 concentrations. OP results from ascorbic acid (AA), glutathione (GSH) and dithiothreitol (DTT) tests evidenced a clear link between specific inorganic components of CP4 with OPAA and the organic fraction of OPGSH and OPDTT. Correlation analyses were performed for OP indicators and the geochemical patterns of CP4. These were compared with respirable dust samples from prior studies. They indicate that Fe (r = 0.83), pyrite (r = 0.66) and sulphate minerals (r = 0.42) (tracing acidic species from pyrite oxidation), followed by S (r = 0.50) and ash yield (r = 0.46), and, to a much lesser extent, Ti, anatase, U, Mo, V and Pb, are clearly linked with OPAA. Moreover, OPGSH correlation was identified by organic matter, as moisture (r = 0.73), Na (r = 0.56) and B (r = 0.51), and to a lesser extent by the coarse particle size, Ca and carbonate minerals. In addition, Mg (r = 0.70), B (r = 0.47), Na (r = 0.59), Mn, Ba, quartz, particle size and Sr regulate OPDTT correlations. These became more noticeable when the analysis was done for samples of the same type of coal rank, in this case, bituminous.

Mineralogy, geochemistry and toxicity of size-segregated respirable deposited dust in underground coal mines.

We focus on a comparison of the geochemistry and mineralogy patterns found in coal, deposited dust (DD), respirable deposited dust (RDD) and inhalable suspended dust (PM10) from a number of underground mines located in China, with an emphasis on potential occupational health relevance. After obtaining the RDD from DD, a toxicological analysis (oxidative potential, OP) was carried out and compared with their geochemical patterns. The results demonstrate: i) a dependence of RDD/DD on the moisture content for high rank coals that does not exist for low rank coals; ii) RDD enrichment in a number of minerals and/or elements related to the parent coal, the wear on mining machinery, lime gunited walls and acid mine drainage; and iii) the geochemical patterns of RDD obtained from DD can be compared with PM10 with relatively good agreement, demonstrating that the characterization of DD and RDD can be used as a proxy to help evaluate the geochemical patterns of suspended PM10. With regards to the toxicological properties of RDD, the Fe content and other by-products of pyrite oxidation, as well as that of anatase, along with Si, Mn and Ba, and particle size (among others), were highly correlated with Ascorbic Acid and/or Glutathione OP.

The geochemical evolution of brines from phosphogypsum deposits in Huelva (SW Spain) and its environmental implications.

The present study focuses on the geochemistry of large phosphogypsum deposits in Huelva (SW Spain). Phosphogypsum slurry waste from fertiliser production was disposed in large ponds containing aqueous waste (i.e. brines) and exposed to weathering. These evaporation ponds were found to be dynamic environments far from attaining steady state conditions where a number of trace pollutants are subjected to temporal variations in response to changing environmental conditions. Chemical, mineralogical and morphological data were used to improve our understanding on the dynamics of a large number of elements in the phosphogypsum-brine-evaporation deposits system. Weekly sampling of brines over the course of 1 yr indicated a substantial enrichment in potentially harmful elements (e.g. As, Cr, Cu, F, Ni, U, V, Zn) present in time-dependent concentrations. The evaporation deposits formed multi-layered precipitates of chlorides, sulphates, phosphates and fluorides containing a large number of pollutants in readily soluble forms. The precipitation sequence revealed a time-dependent composition reflecting alternating precipitation and re-dissolution processes associated with seasonal changes in the local weather conditions. Concatenation of precipitation/re-dissolution stages was found to progressively enrich the brines in pollutants. These findings were supported by the observations from a tank experiment simulating the phosphogypsum-brine-evaporation deposits system under laboratory conditions. Given the substantially high concentrations of pollutants present in mobile forms in the brine-salt system, actions to abate these compounds should be implemented.

Casos de COVID-19 en relación con parámetros ambientales en cinco departamentos de la provincia de Catamarca, Argentina / Cases of COVID-19 in relation to environmental parameters in five departments of Catamarca province, Argentina

Resumen Introducción : El objetivo del trabajo fue estudiar la relación entre el número de casos positivos de CO VID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca. Métodos : Los departamentos estudiados fueron Ca pital, Andalgalá, Paclín, Ambato y Tinogasta, Catamarca, Argentina. Las variables número de casos COVID-19, temperatura y porcentaje de humedad ambiental fueron obtenidos entre abril de 2021 y abril de 2022. La corre lación de variables se analizó mediante el coeficiente de Spearman. Resultados : La temperatura, en relación con los nú meros de casos por COVID-19 mostró valores de co rrelación inversa que oscilaron entre -0.56 y -0.34. El porcentaje de humedad, indicó una relación levemente positiva con el número de casos solo para Capital y Andalgalá con valores de 0.34 y 0.40. Conclusión : Los resultados muestran una relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y hu medad en cinco departamentos de la provincia de Catamarca.

Abstract Introduction : The aim of the study was to investi gate the relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments of the province of Catamarca, Argentina. Methods : The departments Capital, Andalgalá, Paclín, Ambato and Tinogasta, Catamarca, Argentina, were stud ied. Between April 2021 and April 2022 variables analyzed were: number of COVID-19 cases, temperature, and per centage of environmental humidity. The correlation of variables was analyzed by the coefficient of Spearman. Results : The temperature with the numbers of CO VID-19 cases show inverse correlation values that ranged between -0.56 and -0.34. The humidity percentages show a slightly positive relationship only for Capital and Andal galá, with values of 0.34 and 0.40 with the number of cases. Conclusion : The results showed a relationship be tween the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments in the province of Catamarca.

Overcoming Barriers in the Implementation of Programs for Breast and Cervical Cancers in Cali, Colombia: A Pilot Model.

Breast and cervical cancers are leading causes of mortality among women in Latin America. Colombia has universal health care and a government-sponsored 10-year cancer control plan focused on prevention, early detection, and treatment. However, many administrative and social barriers have hindered its success, and a majority of patients are diagnosed at a late stage. Established in 2012, Partners for Cancer Care and Prevention (PFCCAP) works to decrease the burden of these cancers by mitigating the obstacles women face during their cancer diagnosis and treatment. Through community outreach meetings with medical personnel, hospital directors, and government officials, PFCCAP identified major barriers, including lack of trained health care personnel, few centers with adequate screening equipment, and a fragmented health system with significant administrative delays and poor continuity of care. Its solution included monthly teleconferences, biannual on-site training, quality control programs, and improved access to screening equipment. PFCCAP also initiated a patient navigation project. After implementation of the PFCCAP plan of action, from 2012 to 2018, the average time from initial consult to biopsy decreased from 65 to 20 days; from biopsy to diagnosis, 33 to 4 days; and from diagnosis to surgery, 121 to 60 days. To date, more than 1,500 women have benefited from this initiative, which has expanded to other regions. Overall, PFCCAP is creating centers of excellence in strategically located hospitals and promoting the implementation of national guidelines. Although several barriers still exist, PFCCAP is helping to implement an efficient health care model that can be replicated in other underserved populations.

Domestic violence surveillance system: a model.

OBJECTIVE: To develop a domestic violence surveillance system. MATERIAL AND METHODS: The strategies included implementation of a standard digitalized reporting and analysis system along with advocacy with community decision makers, strengthening inter-institutional attention networks, consultation for constructing internal flow charts, sensitizing and training network teams in charge of providing health care in cases of domestic violence and supporting improved public policy prevention initiatives. RESULTS: A total of 6 893 cases were observed using 2004 and 2005 surveillance system data. The system reports that 80% of the affected were women, followed by 36% children under 14 years. The identified aggressors were mainly females' partners. The system was useful for improving victim services. CONCLUSIONS: Findings indicate that significant gains were made in facilitating the attention and treatment of victims of domestic violence, improving the procedural response process and enhancing the quality of information provided to policy-making bodies.

[Distribution of Rotavirus G Genotypes during 10 years in children with acute diarrhea of the city of La Rioja, Argentina. Implications for vaccination] / Genotipos G de rotavirus durante 10 años en niños con diarrea aguda de la ciudad de La Rioja, Argentina. Implicancias en la vacunación.

Vaccination against rotavirus in Argentina is obligatory from January 2015. From 418 stools in children with acute diarrhea were collected from 2000 to 2010 in city of La Rioja, Argentina, Rotavirus was detected. The 90 rotavirus positive stools samples (21.53%) were amplified by RT-PCR and genotyped by PCR-Mix for G1, G2, G3, G4, G9 and G8. The results show that during 2000-2003, the most frequent genotype was G1 and but since 2008, the G2, G3 and G9 genotypes in single and mixed infections were detected. In La Rioja, the vaccines could prevent dehydration in older children the year but children under one year could be vulnerable to the emergence of strains with genic aberrations due to the implementation of vaccination in our region.

La vacunación para rotavirus es obligatoria en Argentina desde enero del 2015. Los genotipos G de rotavirus circulantes previo a la vacunación no fueron estudiados en la Provincia de La Rioja. El objetivo del presente trabajo fue determinar los genotipos G de rotavirus que circulan en La Rioja en niños con diarrea desde 2000 a 2010. Se determinó la presencia de rotavirus del Grupo A por Inmunocromatografía (Biomerieux) en 418 muestras de materias fecales obtenidas en niños con diarrea aguda, hospitalizados y ambulatorios, en ciudad de La Rioja, Argentina. El 40 % de los niños estudiados provenía del interior de la provincia. Las 90 muestras positivas (21,53%) fueron amplificadas por RT-PCR y genotipificadas por Multiplex-PCR para genotipos G1, G2, G3, G4, G9 y G8. Los resultados muestran que el genotipo más frecuente de2000 a2003 fue G1 pero que desde el 2008 se detectaron los genotipos G2, G3 y G9 en infecciones simples y mixtas. Los genotipos G9 y las infecciones mixta, cuádruple y quíntuple, se presentaron en niños menores de un año de vida. Este es el primer reporte de los genotipos G de rotavirus en La Rioja. Los resultados indican que los genotipos G circulantes de rotavirus son compatibles con los que se dispone en la vacuna aunque la presencia de infecciones mixtas y Genotipo G9 en niños menores de un año sugieren una mayor vulnerabilidad de este grupo para la aparición de cepas con derivas génicas durante la implementación de la vacunación en esta Provincia