Loading...
4 results
Search Results
Now showing 1 - 4 of 4
- Environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) exposure in residents living near gas stationsPublication . Barros, Nelson; Carvalho, Márcia; Silva, Cláudia; Fontes, Tânia; Prata, Joana C.; Sousa, André; Manso, M. ConceiçãoThe volatile organic compounds benzene, toluene, ethylbenzene, and xylene (BTEX) are emitted into the atmosphere at gas stations (GS) leading to chronic exposure of nearby residents, which raises public health concerns. This study aimes at determining the contribution of GS emissions to BTEX exposure in nearby residents. Three Control and Exposed areas to BTEX emissions from GS were defined in a medium-sized European city (Porto, Portugal). BTEX atmospheric levels were determined in Control and Exposed areas using passive samplers deployed outdoors (n = 48) and indoors (n = 36), and human exposure was estimated for 119 non-smoking residents using the first urine of the day. Results showed that median BTEX outdoor and indoor concentrations were significantly higher for Exposed than Control areas, with exception of ethylbenzene and xylene indoor concentrations, where no marked differences were found. Comparison of urinary concentrations between Exposed and Control residents demonstrated no significant differences for benzene and ethylbenzene, whereas levels of toluene and xylene were significantly higher in Exposed residents. No marked correlation was obtained between atmospheric BTEX concentrations and urinary concentrations. Data indicate the potential impact on air quality of BTEX emissions from GS, which confirms the importance of these findings in urban planning in order to minimize the impact on health and well-being of surrounding populations.
- Exposure to BTEX in buses: the influence of vehicle fuel typePublication . Fontes, Tânia; Manso, M. Conceição; Prata, Joana C; Carvalho, Márcia; Silva, Cláudia; Barros, NelsonDiesel-fueled buses have been replaced by Compressed Natural Gas (CNG) to minimize the high level of emissions in urban areas. However, differences in indoor exposure levels to Benzene, Toluene, Ethylbenzene and Xylene (BTEX) in those vehicles have not been investigated so far. The primary aim of this study was to determine if passengers are exposed to different BTEX levels when using buses powered by CNG or by diesel, and further explore if indoor levels are influenced by external air quality. For this purpose, BTEX air concentrations were measured in bus cabins (CNG and diesel), parking stations and in a background urban area using passive air samplers. Results showed that BTEX concentrations inside vehicles were higher than outside, but no significant differences were found between buses powered by CNG or by diesel. In CNG vehicles, high and significant positive correlation was found between benzene and the number of journeys in the same route (rs ¼ 0.786, p < 0.05), vehicle operating time (rs ¼ 0.738, p < 0.05), exposure time (rs ¼ 0.714, p < 0.05) and exposure index (rs ¼ 0.738, p < 0.05), but this was not observed for diesel vehicles. Benzene in bus cabins was found to be significantly below reference value for human health protection. However, excepting p-xylene, all other aromatic pollutants have a mean concentration significantly above the lowest effect level (p 0.002 for all comparisons). Additionally, higher BTEX levels in cabin buses than in outdoor air suggest the presence of other emission sources in indoor cabins. These findings emphasize the need for further studies to fully characterize indoor emission sources in order to minimize the negative impact of BTEX exposure to human health.
- Programas de prevenção da obesidade infantilPublication . Silva, Jenny; Silva, CláudiaA obesidade é a doença mais comum na infância nos países desenvolvidos e a sua prevalência continua a aumentar. A elevada prevalência em conjunto com as complicações futuras tornam a obesidade um verdadeiro problema de saúde pública. A infância é um período importante para prevenir e reverter a tendência crescente da obesidade. As intervenções preventivas que encorajam a actividade física e a alimentação saudável, restringindo as actividades sedentárias e sugerindo alterações comportamentais. Estas intervenções deverão envolver não só as crianças mas também toda a família, a escola e a comunidade. Para se alterar o panorama geral da epidemia da obesidade infantil são necessários mais estudos preventivos, de forma criar recomendações clínicas e a desenvolver abordagens de saúde pública mais eficazes. Obesity is now the most common disorder of childhood in the developed world, and its prevalence is still increasing. The combination of high prevalence with adverse consequences has created a public health crisis. Childhood is an important period for prevention to reverse the rising tide of obesity. Preventive interventions that encourage physical activity and a healthy diet restrict sedentary activities and offer behavioural support. However, these interventions should involve not only the child but the whole family, school and community. If the current global obesity epidemic is to be halted, further prevention studies are required in order to expand the currently limited evidence basis upon which clinical recommendations and public health approaches can be formulated.
- Rotulagem nutricional: sua importânciaPublication . Cordeiro, Tânia; Silva, Cláudia; Bento, AlexandraSão descritos os métodos de categorização dos produtos alimentares de acordo com a sua qualidade nutricional como estratégia de promoção da saúde pública através de escolhas alimentares mais saudáveis. São discutidas as abordagens desenvolvidas para a categorização de produtos alimentares utilizando a qualidade nutricional. A melhor abordagem deverá ser capaz de sumariar e sintetizar a composição nutricional de modo a que seja facilmente aplicável a uma grande variedade de produtos, ser compreensível para os consumidores e estar bem regulamentada. This article describes the methods for categorising foods according to their nutritional quality as a strategy for promoting public health through better dietary choices. We discuss well-developed approaches for categorising foods using nutrient profiling. The best approach should be able to summarise e synthesise key nutritional dimensions in a way that is easily applied across a variety of products, is understandable to users and can be strictly defined for regulatory purposes.