The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane...The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of C02, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PMio was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of Florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into Florida added appreciably to PMio trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PMjo -portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl (30%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HC1. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and I< also showed the highest concentrations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of the ambient PAHs associated with PMio are indeed related to preharvest burning, harvesting machinery emissions, bagasse burning in sugarcane mills, and other related activities that consume biomass and/or fossil fuels for sugarcane harvesting and processing.展开更多
Since most of the central regions of the European part of Russia are considered selenium and iodine deficient, the assessment of modern real consumption of chlorine, bromine, iodine and selenium by population of these...Since most of the central regions of the European part of Russia are considered selenium and iodine deficient, the assessment of modern real consumption of chlorine, bromine, iodine and selenium by population of these regions with different diets is an important constituent part of medical monitoring. In this paper, a brief analysis of the impact of these elements on the human body is given. A number of consumed foodstuffs in different food rations (diets) were assessed. Six selected basic food rations, which most fully reflect the specific features of nutrition in the Russian Federation, were chosen. The analysis of the concentration of chlorine, bromine, iodine and selenium in a wide range of food and agricultural products was carried out. The daily intake of these elements in the human body from the selected diets was calculated. A comparison of the real income of chlorine, bromine, iodine and selenium in the human body with a physiologically needed intake was performed. It is proposed to use the coefficient of Kr, which is the ratio of actual intake of the element in the human body to physiologically needed intake. Based on this analysis assessed insufficient or excess supply of chlorine, bromine, iodine and selenium in the human body with these diets in the central regions of the European part of Russia was evaluated.展开更多
文摘The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of C02, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PMio was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of Florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into Florida added appreciably to PMio trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PMjo -portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl (30%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HC1. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and I< also showed the highest concentrations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of the ambient PAHs associated with PMio are indeed related to preharvest burning, harvesting machinery emissions, bagasse burning in sugarcane mills, and other related activities that consume biomass and/or fossil fuels for sugarcane harvesting and processing.
文摘Since most of the central regions of the European part of Russia are considered selenium and iodine deficient, the assessment of modern real consumption of chlorine, bromine, iodine and selenium by population of these regions with different diets is an important constituent part of medical monitoring. In this paper, a brief analysis of the impact of these elements on the human body is given. A number of consumed foodstuffs in different food rations (diets) were assessed. Six selected basic food rations, which most fully reflect the specific features of nutrition in the Russian Federation, were chosen. The analysis of the concentration of chlorine, bromine, iodine and selenium in a wide range of food and agricultural products was carried out. The daily intake of these elements in the human body from the selected diets was calculated. A comparison of the real income of chlorine, bromine, iodine and selenium in the human body with a physiologically needed intake was performed. It is proposed to use the coefficient of Kr, which is the ratio of actual intake of the element in the human body to physiologically needed intake. Based on this analysis assessed insufficient or excess supply of chlorine, bromine, iodine and selenium in the human body with these diets in the central regions of the European part of Russia was evaluated.
