RESUMEN
Bread production is a pivotal component of global nutrition. However, its extensive production imposes significant strain on resources and energy, resulting in substantial environmental consequences. This study focuses on a multidimensional assessment of the environmental sustainability of the bread life cycle as a case study in Iran. By integrating four life cycle assessment (LCA) methods, this research demonstrates a comprehensive analysis of environmental effects, energy consumption, and exergy demand in bread production. It also identifies the hotspot stages and inputs within the bread production chain. Eventually, it proposes strategies for mitigating the environmental impacts in line with sustainable development goals. Data collection involved questionnaires by face-to-face interviews. The LCA evaluation was conducted using SimaPro software. Sustainability analysis was assessed using four different methods: CML, ReCiPe, cumulative energy demand (CED), and cumulative exergy demand (CExD) method, from cradle to bakery gate. The CML method results indicate that the highest environmental impacts are associated with marine aquatic ecotoxicity (157.04 to 193.36 kg 1,4-DB eq), fossil fuel depletion (11.05 to 12.73 MJ), eutrophication (4.20 × 10-3 to 4.70 × 10-3 kg PO4-3 eq), acidification (8.09 × 10-3 to 9.16 × 10-3 kg SO2 eq), and global warming (0.61 to 0.69 kg CO2 eq). The ReCiPe method highlights wheat production stages and gas consumption as the most significant contributors to damage in terms of human health, ecosystems, and resource consumption indicators. The CED method reveals that fossil energy accounts for over 97% of the energy consumed during the bread life cycle. Energy consumption per kilogram of bread ranges from 12.07 to 13.93 MJ. The CExD method for producing 1 kg of traditional bread falls between 32.25 and 35.88 MJ. More than 60% of this value is attributed to renewable resources of water used in irrigation during the wheat farming stage, while over 35% is linked to non-renewable fossil resources, primarily due to the consumption of natural gas in bakery operations. To assess the potential decrease in environmental emissions, a sensitivity analysis was performed, considering the effects of substituting natural gas with biogas and grid electricity with photovoltaic electricity in the bakery. Then, three improved scenarios were developed, each demonstrating effective reductions in environmental impacts, with the most remarkable decreases observed in marine aquatic ecotoxicity (55%) and fossil fuel depletion (44%). Overall, the findings demonstrate that Sangak bread production exhibits a more environmentally friendly profile than other types of bread. These results can guide decision-makers in the bread production industry towards implementing sustainable practices that prioritize resource efficiency and environmental conservation. Also, stakeholders can develop strategies to reduce the environmental impacts and work towards a more sustainable future.
Asunto(s)
Pan , Ambiente , Irán , Desarrollo Sostenible , Conservación de los Recursos NaturalesRESUMEN
In recent years, researchers have extensively investigated the remediation of heavy metal-contaminated soil using plants, microorganisms, and iron nanoparticles. The objective of this study was to investigate and compare the individual and simultaneous effects of Paulownia elongata S. Y. Hu, cyanobacteria (Oscillatoria sp.), arbuscular mycorrhizal fungi (AMF) including Glomus mosseae and Glomus intraradices, and zero-valent iron nanoparticles (nZVI) on the remediation of heavy metal-contaminated soil containing chromium (Cr VI and Cr III) and nickel (Ni). The study found significant variations in parameters such as pH (acidity), electrical conductivity (EC), nitrogen (N), phosphorus (P), potassium (K), and organic carbon (OC) among different treatments. The addition of cyanobacteria, AMF, and nZVI influenced these properties, resulting in both increases and decreases compared to the control treatment. The treatment involving a combination of cyanobacteria, AMF, and nZVI (CCAN25) exhibited the highest increase in growth parameters, such as total dry mass, root length, stem diameter, and leaf area, while other treatments showed varied effects on plant growth. Moreover, the CCAN25 treatment demonstrated the highest increase in chlorophyll a, chlorophyll b, and carotenoid levels, whereas other treatments displayed reductions in these pigments compared to the control. Moderate phytoaccumulation of Cr and Ni in P. elongata samples across all treatments was observed, as indicated by the bioconcentration factor and bioaccumulation coefficient values being less than 1.0 for both metals. The findings provide insights into the potential application of these treatments for soil remediation and plant growth enhancement in contaminated environments.
Asunto(s)
Hongos , Metales Pesados , Micorrizas , Nanopartículas , Oscillatoria , Contaminantes del Suelo , Hierro/química , Clorofila A , Metales Pesados/análisis , Níquel , Biodegradación Ambiental , Nanopartículas/química , Suelo/química , Contaminantes del Suelo/análisis , Raíces de Plantas/químicaRESUMEN
The undeniable impact of plants in reducing air pollution and the crucial role of nutrition in improving stress tolerance in plants has brought attention to the use of eco-friendly fertilizers. The objective of the study was to investigate how Biogas-digestate (BD) can enhance the tolerance of green roof plants in capturing air pollutants. Four plant species, namely reflexed stonecrop (Sedum reflexum), blue fescue (Festuca glauca), garden mum (Chrysanthemum morifolium), and Peppermint (Mentha piperita) were planted in three urban sites in Mashhad, Iran, with different levels of air pollution. The physiological, biochemical, and morphological characteristics of the treated plants were compared to assess their ability to trap air pollutants. The results showed that the treated M. piperita at Razavi with BD, exhibited the highest level of APTI. Although it was influenced by the site conditions, the determination of the optimum API yielded same results. The F. glauca treated in Khayyam had the highest proline content, while S. reflexum at the Honarestan site had the lowest H2O2 level, without significantly affecting BD. F. glauca, S. reflexum, and M. piperita exhibited the highest levels of SOD, PPO, and GPX activity, respectively, which were significantly increased by the BD treatment. Most of the heavy elements showed increased levels with BD treatment, and M. piperita had the highest concentrations of heavy elements. The leaf surfaces of S. reflexum and M. piperita, had the highest and lowest deposition of particulate matter (PMs), respectively. Carbon and oxygen constituted the majority of PMs on the surface of leaves at all three study locations. The following ranks included the elements Si, Ca, Mg, and Al. BD, particularly in the case of S. reflexum and M. piperita, enhanced the plants' tolerance to air pollution. It is recommended to cultivate S. reflexum using BD on the green roof in polluted areas due to its superior capacity to absorb PMs and the fact that it is not edible.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Biocombustibles/análisis , Monitoreo del Ambiente/métodos , Peróxido de Hidrógeno , Hojas de la Planta/química , PlantasRESUMEN
Heavy metals are among the most dangerous contaminants in the environment. Organic components and plant species that can accumulate and stabilize heavy metals in their organs are a good option for soil remediation of these elements. Therefore, this study aimed to investigate the effects of manure and biochar on the accumulation of heavy metals by Salicornia species. Salicornia persica Akhani and Salicornia perspolitana Akhani were cultivated outdoor in experimental pots. The effects of experimental treatments, including Cr (VI) concentrations, manure, and biochar on the two studied species, were investigated. The results indicated a significant effect (p < 0.05) of biochar on the accumulation of heavy metals by two species, S. persica and S. perspolitana, so that Cr concentrations in the roots and shoots were 258 and 5.41 mg/kg, respectively. In addition, Cr accumulations under manure treatments in the roots and shoots were 334.34 and 9.79 mg/kg, respectively. The content of photosynthetic pigments in both S. persica and S. perspolitana species under biochar treatment was higher than in control and manure treatments. In general, one can conclude that the accumulation of Cr in S. perspolitana was higher than in S. persica. Applying biochar and manure amendments could stabilize Cr in soil and reduce Cr accumulation in both S. persica and S. perspolitana species.
Asunto(s)
Metales Pesados , Contaminantes del Suelo , Estiércol , Contaminantes del Suelo/análisis , Carbón Orgánico , Metales Pesados/análisis , Biodegradación Ambiental , SueloRESUMEN
One of the most pressing issues confronting the civilized and modern world is air pollution. Particulate matter (PM) is a well-known pollutant that contributes significantly to urban air pollution and has numerous short- and long-term adverse effects on human health. One method of reducing air pollution is to create green spaces, mainly green walls, as a short-term solution. The current study investigated the ability of nine plant species to reduce traffic-related PM using a green wall system installed along a busy road in Mashhad, Iran. The main aims were (1) estimate the tolerance level of plant species on green walls to air pollution using the air pollution tolerance index (APTI); (2) assess the PM capture on the leaves of green wall species using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, and accumulation of heavy metals using inductively coupled plasma (ICP); (3) select the most tolerance species for reducing air pollution using anticipated performance index (API). The plants' APTI values ranged from 5 to 12. The highest APTI value was found in Carpobrotus edulis and Rosmarinus officinalis, while Kochia prostrata had the lowest. Among the APTI constituents, leaf water content (R2 = 0.29) and ascorbic acid (R2 = 0.33) had a positive effect on APTI. According to SEM analysis, many PMs were adsorbed on the adaxial and abaxial leaf surfaces, as well as near the stomata of Lavandula angustifolia, C. edulis, Vinca minor, and Hylotelephium sp. Based on EDX analysis, carbon and oxygen formed the highest amount (more than 60%) of metals detected in the elemental composition of PM deposited on the leaves of all species. The Sedum reflexum had the highest Cr, Fe, Pb, and As accumulation. The concentrations of all heavy metals studied in green wall plants were higher than in the control sample. Furthermore, the C. edulis is the best plant for planting in industrial, urban areas of the city based on APTI, biological, economic, and social characteristics. It concludes that green walls composed primarily of plants with small leaves can significantly adsorb PM and accumulation of heavy metal.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Metales Pesados , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ácido Ascórbico/farmacología , Carbono/análisis , Monitoreo del Ambiente/métodos , Humanos , Plomo/análisis , Metales Pesados/análisis , Oxígeno/análisis , Material Particulado/análisis , Hojas de la Planta/química , Plantas , Agua/análisisRESUMEN
In recent decades, soil contamination with heavy metals has become an environmental crisis due to their long-term stability and adverse biological effects. Therefore, bioremediation is an eco-friendly technology to remediate contaminated soil, which the efficiency requires further research. This study was designed to comparatively investigate two strategies: bioaugmentation by using a cyanobacterial species (Oscillatoria sp.) and bioaugmentation-assisted phytoremediation by using Oscillatoria sp. and purslane (Portulaca oleracea L.) for the bioremediation of soil contaminated by heavy metals (Cr (III), Cr (VI), Fe, Al, and Zn). Various quantities of biochar (0.5, 2, and 5% (w/w)) were used as an amendment in the experiments to facilitate the remediation process. The results of the bioaugmentation test showed that applying biochar and cyanobacteria into contaminated soil significantly increased the chlorophyll a, nitrogen, and organic carbon contents. In contrast, the extractable fractions of Cr (III), Cr (VI), Zn, Al, and Fe declined compared with those of the control treatment. The highest reduction content (up to 87 %) in the extractable portion was obtained for Cr (VI). The development of longer root and hypocotyl lengths and vigour index from lettuces and radish seeds grown in the remediated soil confirmed the success of remediation treatments. Moreover, the findings of the bioaugmentation-assisted phytoremediation test displayed a reduction in the bioavailable fraction of Cr (III), Cr (VI), Zn, Al, and Fe. Cr (III) presented the highest reduction (up to 90 %) in metal bioavailability. With cyanobacteria inoculation and biochar addition, the shoot and root lengths of purslane grew 4.6 and 3-fold while the heavy metal accumulation decreased significantly. Besides, these treatments enhanced the tolerance index (TI) quantities of purslane whereas diminished its bioaccumulation coefficient (BAC) and bioconcentration factor (BCF) values. For all heavy metals (except Zn), translocation factor (TF) and BAC values were found to be less than 1.0 at all treatments, indicating the successful phytoextraction by the purslane. These results suggest that the purslane can be considered an excellent phytoextracting agent for soils contaminated with heavy metals.
Asunto(s)
Cianobacterias , Metales Pesados , Portulaca , Contaminantes del Suelo , Biodegradación Ambiental , Carbón Orgánico , Clorofila A , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisisRESUMEN
Nowadays, due to the most application of montmorillonite, its purification from raw bentonite has great importance. More than 76% of bentonite is composed of montmorillonite, and its industrial applications are related to its montmorillonite content. In this study, the nanoclay was extracted from bentonite by the use of centrifugal force. The results of the field-emission scanning electron microscopy (FE-SEM) analysis show that the nanosized of purified montmorillonite has a sheet structure with a spacing of 22.41 nm and 45.0 nm. The sharp peaks in X-ray diffraction analysis (XRD) illustrated that the montmorillonite purified successfully, and the results of Fourier-transform infrared spectrophotometry (FT-IR) revealed the successful incorporation of the metabolic extraction within the montmorillonite. By comparison of Brunauer-Emmett-Teller (BET) results with IUPAC, it can be realized that the synthesized montmorillonite nanoclay has a microporous structure (< 2 nm) with a surface area of 11.325 m2 g-1. According to IUPAC classification, the BET isotherms of montmorillonite and bentonite indicate a hysteresis loop belonging to the type H3. Finally, the economic analysis results revealed to this method could be the best option for achieving high purity montmorillonite for future applications.
Asunto(s)
Bentonita , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos XRESUMEN
The leather industry is one of the major producers of wastewater, releasing large amounts of various chemicals into the environment. Chromium (Cr) is the most commonly used agent in the tanning industry. Accumulation in the animal body can adversely affect the functioning of animal tissues. The current study investigated the toxic effects of Cr on lung, kidney, liver, and testicular tissues in Libyan jirds (Meriones libycus) inhabiting the area surrounding Ghazghan leather industrial town, Mashhad, Iran. Average Cr concentrations were found to be significantly higher in samples from contaminated areas than controls (p < 0.05). The highest accumulation of Cr was found in lung tissue, while the liver tissue showed the lowest. The results also showed that sex and age had no significant effect on Cr accumulation in any tissue at either sampling area (p < 0.05). Histological analyses showed that Cr accumulation had caused changes in tissue samples from Libyan jirds from the contaminated area. Hyperemia was observed in all tissues. In kidney tissue, necrosis and degeneration of the epithelial cells of the tubules were seen as well, and in one case, we also observed hemorrhage. In liver tissue, necrosis, degeneration, and inflammation were observed, along with one case, of fibrosis. In lung tissue, we observed emphysema, hemorrhage, and inflammation. Testicular tissue also showed a considerable lesion. Given the proximity of specimens' habitat to an area of importance, i.e., the industrial town, and the species' dependence on its habitat for nutrition, Libyan jirds are particularly useful for monitoring. Thus, they can be used to monitor the level of contamination in future studies.
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Cromo/análisis , Industrias , Animales , Gerbillinae , Residuos Industriales/análisis , Irán , Curtiembre , Aguas Residuales/análisisRESUMEN
Food waste has influenced food security for poor people, food safety, economic development, and the environment. The objective of this paper is to examine the food waste reduction behavior in a sample of Iran households. The study used the Theory of Planned Behavior (TPB) as its conceptual framework and further attempted to extend the TPB by incorporating the addition of new variables (e.g., marketing addiction, the perceived ascription of responsibility, moral attitude, waste-preventing behavior, and socio-demographic characteristics). Data was gathered using a systematic random sampling technique and analyzed with structural equation modeling (SEM). The sample size used in the study was 382. The results revealed that TPB and Extended Theory of Planned Behavior (ETPB) models exhibited a reasonable fit to the data. If key goals are to predict intention to reduce food waste (IRFW), the TPB is preferable due to a smaller quantity of comparison criteria. However, if the key goal is to explain IRFW, the ETPB is preferable due to higher R2 compared with others. Besides, the variable "waste-preventing behavior" was the most significant variables influencing the intention to reduce food waste. Socio-demographic characteristics such as age, level of education, and income were found to be statistically significant predictors of intention. Finally, the implication for management and the scope for future research have been discussed.
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Alimentos , Residuos de Alimentos , Eliminación de Residuos , Femenino , Humanos , Intención , Irán , Masculino , Encuestas y CuestionariosRESUMEN
Mining activity constitutes a potential source of heavy metal pollution in the environment. Long-term exposure to heavy metals (e.g., cadmium) has adverse health effects. Rodents frequently serve as bioindicators to monitor the levels of heavy metals in the environment. In the present study, concentrations of 10 heavy metals (Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb, Sb, and Zn) in kidney, liver, and muscle tissue of the Persian jird (Meriones persicus) were evaluated. This is the first study to examine the histopathological changes in Persian jird tissues caused by the bioaccumulation heavy metals. The samples were taken at location that surrounded by Sangan Iron Ore Mine (SIOM) mining activities, in northeastern Iran. The results show that the highest concentrations for the metals were observed in kidney and liver, whereas lowest concentrations were found in muscle of Persian jirds. The concentration of Pb was below the limit of detection. Sex and age were two factors that could explain the different levels of heavy metal bioaccumulation, which affects the concentration of some metals. Adults had significantly higher Cu and Cd levels compared to juveniles. Males bioaccumulated more Zn in their kidneys than females, whereas females bioaccumulated more Fe in their livers. As expected, heavy metals affected various organs of the studied specimens. Hyperemia, hemorrhage, necrosis, and degenerative damage to the epithelial cells of the tubules, the presence of hyaline casts, and in one case, mononuclear leukocyte infiltration, were observed in samples of renal tissue. Hemorrhage and hepatocyte vacuolization were the most common histopathological changes found in samples of hepatic tissue. These effects and the concentrations of heavy metals in the studied specimens indicate the need for monitoring and frequent sampling to evaluate long-term persistent pollutants.
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Monitoreo del Ambiente , Gerbillinae/fisiología , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Animales , Cadmio , Contaminantes Ambientales , Femenino , Irán , Hierro , Masculino , Metales Pesados/análisis , Metales Pesados/toxicidad , Minería , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidadRESUMEN
The effect of drinking water treatment sludge (DWTS) as a mixture additive, on biogas and methane production from food waste was studied. Mesophilic anaerobic digestion of food waste with 5 concentrations of DWTS (0, 2, 6, 12, and 18â¯ppm) was carried out. It was found that DWTS can significantly enhance biogas and methane yield. The highest biogas (671â¯Nml/g VS) as well as methane yield (522â¯Nml/g VS) was observed when 6â¯mg/kg DWTS was added. This is equal to 65 and 58 percent increase in comparison with the control digester. The calculated lag time for methane was found to be in between 3.3 and 4.7â¯days. The DWTS also reduced the lag phase and retention time. The biogas experimental data was fitted with the modified Gompertz and the first-order kinetic models with R2 higher than 0.994 and 0.949, respectively. The ratio of the experimental biogas production to the theoretical biogas production (É) for control sample was 0.53 while for other samples containing additive were higher than 0.78.