Due to the COVID-19 pandemic, lockdown restrictions were established around the world. Many studies have assessed whether these restrictions affected atmospheric pollution. Comparison between them is difficult as the periods of time considered are generally not the same and thus, different conclusions may be reached.
View Article and Find Full Text PDFInt J Environ Res Public Health
April 2022
This study examined the migratory status/ethnic inequities in dental caries in school children aged 4-9 years ( = 1388) and the impact of the Children's Oral Health Program in the Municipality of Bilbao in the Basque Country Region, Spain. Using the 2017 Children's Oral Health Survey, log binomial regression was used to quantify the association of parental immigration status/ethnicity with tooth decay for (1) the primary and the permanent dentitions, separately, in children 4-9 years old; and (2) for the permanent dentition in children aged 7-9 years. Compared with Spanish children, Spanish Roma and immigrant children had a higher probability of tooth decay in primary and permanent teeth after adjustment.
View Article and Find Full Text PDFSettleable particulate matter (SPM) was collected at two sampling points within an urban area highly affected by nearby industrial activities. Total deposition values up to 386 mg ·m·d were registered, the majority of samples exceeding the limit value established in the legislation in force in Spain until 2002 (300 mg·m·d). Dry deposition values showed high variability (8.
View Article and Find Full Text PDFThere is growing interest in investigating the human health risk associated with metals in airborne particulate matter. The objective of this paper is the health risk assessment of Al, Be, Sb, Sn, Ti and Tl in PM under different advections of air masses. These metals/semi-metal were studied in samples collected in an area influenced by industrial activities in northern Spain with the aim of analysing the variations in PM metal/semi-metal.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2017
Thirty-two chemical species were determined in PM sampled at a suburban site on the north coast of Spain. Enrichment factors were applied to infer their soil/non-soil origin. The geochemical ratios were calculated using two databases: soil composition from locations in the surroundings of the sampling station and the Earth's average upper-crust composition.
View Article and Find Full Text PDFTo increase the production of methane, when cattle manure (CM) is digested, pretreatments can be applied and/or the manure can be co-digested with other wastes. In this research work, a mixture of CM, food waste (FW) and raw glycerine (Gly) in a proportion in weight of 87% CM, 10% FW and 3% Gly was digested, (a) without pretreatment and (b) with pretreatment by ultrasound, applying a sonication energy of 1040 kJ/kg total solids. Specific methane production was 290 L CH/kg volatile solids (VS) without pretreatment and 520 L CH/kg VS with pretreatment.
View Article and Find Full Text PDFThis paper presents a study of the quartz fibrous filters used as a substrate for capturing the particulate matter (PM) present in the air. Although these substrates are widely used in environmental applications, their microstructure has been barely studied. The behavior of these devices during the filtration process was investigated in terms of their microstructure and the quartz fibers.
View Article and Find Full Text PDFBiochemical methane potential (BMP) tests have been carried out on sewage sludge from two wastewater treatment plants to assess the effect of additives (FeCl(3) and two cationic polyelectrolytes) used in sludge dewatering. BMP tests were also carried out on the concentrated solid phase from the enzymic hydrolysis pre-treatment (42 °C, 48 h). FeCl(3) had no significant effect on specific methane production, obtaining 242-246 LCH(4)/kgVSo.
View Article and Find Full Text PDFThe leachates produced at the municipal solid waste (MSW) landfill of Asturias (Spain) were submitted to a biological treatment consisting of a pressurized nitrification-denitrification process followed by ultrafiltration. The effluent from this treatment plant has a high chemical oxygen demand : biochemical oxygen demand (COD : BOD( 5)) ratio (about 25 : 1). The COD values of the effluent are above the discharge limits permitted by current legislation and therefore require a final treatment.
View Article and Find Full Text PDFDifferent autonomous communities located in northern Spain have large populations of dairy cattle. In the case of Asturias, the greatest concentration of dairy farms is found in the areas near the coast, where the elimination of cattle manure by means of its use as a fertilizer may lead to environmental problems. The aim of the present research work was to study the anaerobic treatment of the liquid fraction of cattle manure at mesophilic temperature using an upflow anaerobic sludge blanket (UASB) reactor combined with a settler after a pasteurization process at 70 degrees C for 2 hr.
View Article and Find Full Text PDFWater Environ Res
March 2006
A study was conducted of the viability of using the cationic exchange resins Amberlite IR-120 and Lewatit SP-112 to treat rinse water generated in the galvanizing process as well as acidic wastewater containing zinc (Zn) and iron (Fe). Solutions containing either 100 mg/L of Zn at pH 5.6 (rinse water) or Fe and Zn at concentrations of 320 and 200 mg/L at pH 1.
View Article and Find Full Text PDFDirective 1994/62 concerning packaging and packaging waste and Directive 1999/31 related to waste disposal will substantially modify the management and treatment of Municipal Solid Waste (MSW) in Europe. In this study, a life cycle analysis has been carried out of the different possibilities of managing Municipal Solid Waste in Asturias. The "Integrated Waste Management" (IWM-1) model was employed, analysing the different alternatives for collection and treatment of MSW.
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