Sugarcane Burning Research Articles

Burning fields, fading memories: exploring the effects of sugarcane burning on air quality and cognitive functioning – A case study in Northeast Thailand

This study assessed the relationship between PM2.5 concentration and the working memory of sugarcane farmers (n = 444) in Khon Kaen Province, one of the largest sugarcane producers in the Northeast region of Thailand. The relationship between the ambient PM2.5 concentrations and the working memory of sugarcane farmers was evaluated using two working memory outcomes. These outcomes included a working memory difficulty score derived from self-report of difficulty in daily tasks that require working memory and an objective memory test score consisting of a set of number recall exercises. The PM2.5 concentration data in this study were obtained from air quality monitoring stations located in the vicinity of the study locations, ensuring both precision and relevance to local air conditions. The regression results showed that farmers in the low-burn farming zone had less difficulty with working memory and better performance on number recall exercises, compared to farmers in the high-burn farming zones, even after controlling for health and socio-economic factors. Our findings highlight the potential impacts of PM2.5 exposure on the cognitive functions of farmers who burn sugarcane residues in Thailand. Our study supports the need for the government of Thailand or health agencies to establish an effective policy to reduce sugarcane residue burning in Thailand.

Abstract A098: Lung cancer disparities among African Americans and other low-income communities in South Florida

Abstract Lung cancer is by far the leading cause of cancer death in the US, accounting for about 1 in 5 of all cancer deaths. Each year, more people die of lung cancer than of colon, breast, and prostate cancers combined. The American Cancer Society estimates that in the US, in 2024, there will be about 234,580 new cases of lung cancer (116,310 in men and 118,270 in women). It estimates there will be around 125,070 deaths from lung cancer (65,790 in men and 59,280 in women). Though these deaths can mainly be attributed to smoking, environmental factors have also had adverse effects on human health and lung cancer. We see an example of this in Florida with agricultural burning, specifically sugarcane burning. Sugarcane is one of the most important cash crops for Florida, around 10% of sugar produced in the United States comes from Florida. However, despite the economic importance of this crop, its harvesting process is controversial creating air pollution that is having adverse health effects on the surrounding communities. This review will discuss the impact of sugarcane burning on African Americans and other low-income communities, and how it’s exacerbating health issues, specifically lung cancer. As well as suggest better alternatives to sugarcane harvesting. Citation Format: Miles Jordan, Steven Erwell, Ben Mwashote, Bereket Mochona. Lung cancer disparities among African Americans and other low-income communities in South Florida [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A098.

Sugarcane harvesting systems in Brazil: Effects on soil carbon stocks and ethanol payback time

AbstractReplacing the burnt sugarcane harvesting system with unburnt sugarcane is important for the sustainability of the sugarcane sector in Brazil. Thus, quantifying the impact of the change in the sugarcane harvesting system on soil organic carbon (SOC) stock in Brazil is necessary, as it will allow the refinement of data on SOC, which is essential for the preparation of the national inventory of emissions and removal of greenhouse gases (GHGs), in addition to contributing to national public policies. We used data from both soil sampling and literature review in this study, resulting in 210 pairs of comparisons: 84 for the conversion from burnt sugarcane to unburnt sugarcane; 95 for the conversion from native vegetation to unburnt sugarcane; and 31 for the conversion from native vegetation to burnt sugarcane (NV–burnt), which we analysed using a mixed linear model. In Brazil and the South‐Centre region, burnt–unburnt conversion results in a progressive increase in SOC stocks over time, in surface and subsurface layers. Over 20 years, the NV–burnt conversion showed SOC losses between 15% and 32%, and the NV–unburnt conversion showed losses between 27% and 35%. SOC change rates showed gains of 0.32 and 0.59 Mg C ha−1 year−1 for burnt–unburnt, and losses ranging from 0.82 to 1.06 Mg C ha−1 year−1 for conversions from native vegetation. The time required to offset the negative carbon balance of the NV–unburnt conversion is 6.4 and 8.2 years, being shorter than the payback time of the NV–burnt conversion, which is 9.9 and 9.2 years, in the 0–30 and 0–50 cm layers, respectively.

Sugarcane Burning: Why?

The sugarcane harvesting practices of farmers pose a recurring problem of burning the sugarcane fields every year, leading to the release of PM 2.5, which is hazardous to health and a matter of concern for all parties involved. The objective of this research is to investigate the causes of sugarcane burning by farmers. Data is collected through participatory observation methods and group discussions with a sample group of farmers in the provinces with the highest incidents of sugarcane field fires, namely Nakhon Ratchasima, Kalasin, and Khon Kaen in the northeastern region of Thailand during the 2021/2022 production season. Content analysis techniques are employed to identify the reasons behind the behavior of burning sugarcane. The findings reveal that sugarcane burning has been a long-standing practice among farmers, and the prevalence of burning has increased due to a shortage of labor for sugarcane cutting. The available machinery for sugarcane cutting is insufficient and unsuitable for the farmers' fields. Farmers who burn sugarcane fields are aware of the health impacts and have benefited from the government's measures to address the issue of sugarcane field fires. However, it is observed that the quantity of burnt sugarcane still exceeds the government's target, because burning sugarcane is a cost-effective, convenient, and rapid method. It is found that penalizing farmers at a rate of 30 Baht per ton of burnt sugarcane and providing assistance at a rate of 120 Baht per ton of fresh-cut sugarcane does not sufficiently motivate farmers to change their sugarcane burning behavior.

Greenhouse gas emission implications of small-scale sugarcane farmers’ trash management practices: A case for bioenergy production in South Africa

Sugarcane trash is a source of biomass available for energy generation. However, this potential has not been explored in the South African small-scale sugarcane sector. The current trash management practices of farmers, especially, pre-harvest burning, have huge negative environmental implications. Sustainable management of sugarcane trash could help address several challenges in the sugarcane industry including the high cost of irrigation. Therefore, this study is meant to assess small-scale growers’ trash management practices and their implications on greenhouse gas emissions. It also ascertains the potential for using sugarcane trash in the co-generation of electricity. The study was conducted in two communities in KwaZulu-Natal and Mpumalanga provinces with 330 small-scale farmers. A probit regression was used to determine factors that influence farmers’ trash management practices. Other analyses such as estimations of the amount of available trash, burning emissions and potential energy from sugarcane were informed by previous studies. The findings showed that pre-burning of sugarcane is a common practice among smallholder producers in South Africa. However, some farmers have attempted to move away from this practice opting to leave their sugarcane in the field or use it for compost. The farmers’ burning of sugarcane releases an estimated 0.08 tCO2-e per ha into the atmosphere. In total, the estimated greenhouse gas emissions from sugarcane burning of all small-scale growers in the two provinces are 725 tCO2-e per annum. The findings also revealed that having more land, poor endowment with psychological capital, lack of access to extension, limited resources, and working in silos compound the practice of burning sugarcane. The estimated energy potential from small-scale sugarcane producers in the country, using a 50 % recovery efficiency and 36 % energy conversion efficiency is 150,323.3 MWh. The study proposes several recommendations for improving trash management practices and initiating the co-generation of electricity from trash in the small-scale sugarcane industry.

Characterization and optimisation of physical/mechanical properties of aluminium/alumina/sugarcane‐bagasse‐powder composites using Taguchi technique

AbstractBurnt sugarcane bagasse powder (SCBP), with its low density, accessibility, and renewal, is an economically reinforcing material. This study fabricated composites, i. e., aluminium/alumina/burnt sugarcane bagasse powder, through the powder metallurgy route. The physical, mechanical, microscopic, and chemical characterization of the composites, such as relative density, microhardness, uniaxial compression, scanning electron microscopy, and x‐ray diffraction, has been conducted. There is a gain in relative density, microhardness and ultimate compression strength of about 2.25 %, 48.07 % and 33.34 % respectively, compared to the base composite (aluminium/4 wt.‐% alumina) at 3 wt.‐% burnt sugarcane bagasse powder. The Taguchi methodology is used as a statistical tool to optimise the response variables. An analysis of variance (ANOVA) is used to find the contribution of input parameters to response variables, and the regression models have been developed. The contribution of factors ‘burnt sugarcane bagasse powder wt.‐%’ and ‘time’ on relative density is 81.65 % and 13.64 %, respectively, while the contribution of the same factors on microhardness is 95.98 % and 3.377 %, respectively. The results of the Taguchi method reveal that the optimised conditions for the highest relative density and microhardness are 3 wt.‐% burnt sugarcane bagasse powder and 2.5 h, which have confirmed the experimental results.

Reframing the wicked problem of pre-harvest burning: A case study of Thailand's sugarcane

Pre-harvest sugarcane burning persists in many countries though there are policies prohibiting the practice. As problems related to sugarcane harvesting are complex, a thorough understanding of the problems for policy formulation is required. The objective of this study was to reanalyze or reframe problems of sugarcane harvesting and pre-harvest sugarcane burning. Concepts of wicked problems, practical reasoning and policy reframing were applied. The study used a participatory modeling approach to illustrate the case of Thailand. Wickedness was shown by complexity and uncertainties of factors intertwining with values related to adoption of harvesting methods; green mechanical, green manual and burnt manual. As timeliness of harvest was the top priority, the burnt method was considered more efficient. It was easier, faster, cheaper and more suitable under unfavorable circumstances for the green methods. The policy to reduce burnt-harvested sugarcane was not so effective and also led to the undesired ‘green but unclean’ method. To frame harvesting problems based on emissions of fine particulates (PM2.5) from sugarcane burning was not a good choice. Incomplete problem sense-making and poor problem frame were indicated. Most farmers were unable to associate sugarcane burning with environmental problems of PM2.5 (and also global warming/climate change) and livelihood impacts. Nevertheless, a larger concern over climate variations was perceived by a majority of farmers. Farmers who adapted relied primarily on green harvesting and the use of residues as trash blankets. Through policy reframing, inefficient green harvesting was seen as a better frame. The new frame enabled farmers linking agricultural practices to sustainability of environment, productivity and livelihoods in the context of climate change. Using participatory modeling for reframing policy problems in general and wicked problems in particular was shown to be powerful and contributing to originality.

Assessment of the Effect of Transit Time between Harvesting and Processing on the Physicochemical Quality Parameters of Preharvest Burnt Sugarcane

Aim: This study was aimed at assessing the effect of time interval between harvesting and processing on the physical and chemical quality parameters of pre-harvest burnt sugarcane
 Study Design: An experimental research design was carried out that involve random selection of samples and sent to laboratory for analysis
 Place and Duration of Study: The study was carried out on July from 26th to 30th 2023 in Kilombero Valley located in the eastern part of Tanzania, between latitude 7 0 42'42'S and longitude 37 0 00'00'E. 
 Methodology: The NCO 376 variety of sugarcane was used, that were cut below ground level, the tops removed, stalks tightened in bundles. The sample size was 15. each sample constituted of 30 burnt sugarcane stalks samples that were randomly collected and sent to laboratory for analysis after 24 ,72 and 120 hours of storage. On every respective storage time, the samples were scratched with knife to remove external contaminants, the stalks were then milled using two roller machines to extract juice. The juice was filled and sealed in sterilized and labelled bottles ready for laboratory analysis. The laboratory analysis data collected were coded and entered in excel sheet and analysed using Statistical Package for Social Science (SPSS) version 25.
 Results: The result shows the means values for pH, brix , pol, purity and weight decreased with increase in storage time whereas the means values for dextran, yeast and Leuconostoc increased with increase storage time The results revealed that purity values were satisfactory in all storage time levels as compared to SASTA standard purity values (97.0 – 98.0% ), whereas mean values for brix and pol stored for 120 hours of storage time was not satisfactory.as compared to SASTA standard values for brix ( 18 – 23%) and pol (14 – 21%) .Dextran concentration was high as compared to South African Sugar Terminals (SAST) that maximum requirement for dextran is 150 mg/kg, dextran level as the measure of microbial deterioration was high in 72 and 120 storage hours indicating microbial contamination.
 Conclusion: Farmers and processors should be well informed about the consequence of delayed processing burned sugarcane to avoid economic loss for farmers and processors.

Chemical Fingerprinting of Biomass Burning Organic Aerosols from Sugar Cane Combustion: Complementary Findings from Field and Laboratory Studies.

Agricultural fires are a major source of biomass-burning organic aerosols (BBOAs) with impacts on health, the environment, and climate. In this study, globally relevant BBOA emissions from the combustion of sugar cane in both field and laboratory experiments were analyzed using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry. The derived chemical fingerprints of fresh emissions were evaluated using targeted and nontargeted evaluation approaches. The open-field sugar cane burning experiments revealed the high chemical complexity of combustion emissions, including compounds derived from the pyrolysis of (hemi)cellulose, lignin, and further biomass, such as pyridine and oxime derivatives, methoxyphenols, and methoxybenzenes, as well as triterpenoids. In comparison, laboratory experiments could only partially model the complexity of real combustion events. Our results showed high variability between the conducted field and laboratory experiments, which we, among others, discuss in terms of differences in combustion conditions, fuel composition, and atmospheric processing. We conclude that both field and laboratory studies have their merits and should be applied complementarily. While field studies under real-world conditions are essential to assess the general impact on air quality, climate, and environment, laboratory studies are better suited to investigate specific emissions of different biomass types under controlled conditions.

The Double Trouble Monster – Unmasking Hidden Tuberculosis in Silicosis Patients: A Case Series

Abstract Tuberculosis occurs commonly in silicosis and is difficult to diagnose. We are presenting four cases of silicotuberculosis. The first three cases of silicotuberculosis have occupational risk factors such as borewell driller, construction sites, and quarry presented with silicotuberculosis clinic radiological features with negative sputum acid-fast bacilli and positive results for tuberculosis obtained from bronchoalveolar lavage samples. The last case developed silicosis due to inhalational burned sugarcane crops. Antituberculosis therapy started after microbiological confirmation for tuberculosis. Hence, a vigorous search of tuberculosis in silicosis patients is highly warranted.

Toward Zero Agro-Waste: A Business Model for Sugarcane Leaves Management in Thailand

Sugarcane is one of the oldest crops ever cultivated by humans and has a long history. Currently, the prevalent practice of burning sugarcane fields increases environmental concerns because many farmers frequently use this method to facilitate the harvest process and prepare the area for the next planting crop. Thus, the effective use of sugarcane leaves with proper management can overcome this problem. This paper represents sugarcane leaf management by developing a business model focused on collection, densification, and transportation, explicitly targeting the conversion of waste sugarcane leaves into fuel for a biomass power plant. The business model is categorized into two primary groups: the farmer group and the middleman group. Both groups are incentivized to invest in tools and equipment for collecting and densifying biomass, thereby facilitating the effective performance of the model. Furthermore, an economic analysis has been conducted encompassing an investment cost evaluation and the estimation of the payback period for this business model. The results indicate that the farmer group demonstrates a payback period of 1.72 years, while the middleman group reveals a longer payback period of 2.06 years. This strategic approach not only enhances the value of biomass waste but also significantly reduces the unwanted burn on farming fields, effectively mitigating air pollution.

Study of sugarcane bagasse/straw combustion and its atmospheric emissions using a pilot-burner.

This work conducted experimental combustion on a closed chamber using two different materials: mixture (1:1) sugarcane bagasse/straw and pre-treated biomass. The sampling method was an Andersen cascade impactor with eight stages. Tests were carried out on untreated biomass varying the velocities observed in the sampling duct (4.18; 5.20, 6.85, and 8.21m.s-1). Pre-treated biomass tests were performed at 4.19m.s-1 because in this condition there is a higher speed stability inside the duct. During the combustion tests, the concentration of emitted particles was higher for the lower speed range, with an order of 4.19 > 5.40 > 6.85 > 8.21m.s-1. The higher speeds observed inside the duct behaved as a dragging agent for particulate material. For the tests at the speed of 8.21m.s-1 where the flow inside the duct was 0.088m3s-1, this behavior is more evident. Considering the fine diameter particles (< 2.5µm), they were emitted in a higher concentration, due to the biomass combustion process, which results in higher emission of ultrafine particles. The emission factors (EFs) obtained for PM10 for untreated biomass were in the range of 0.414 and 0.840. On the other hand, considering the pre-treated biomass, these factors were 0.70 and 1.51. The EFs of PM from the burning of the pre-treated biomass were higher when compared to untreated biomass, which is mainly due to the higher temperature of the process due to the higher HHV (higher heating value) of this material, caused by the removal of hemicellulose (4.71 times) and a proportional increase in lignin (1.52 times). Biomass combustion has the potential to partially replace fossil fuels in heat and energy generation. Nevertheless, more stringent and comprehensive legislation should be established to ensure that air quality is maintained. Furthermore, the emission factors obtained in this study might be useful as input data for air quality modeling in the context of sugarcane's burning biomass, thus, contributing to the generation of inventories that include emissions of this nature.

Sugarcane ash and sugarcane ash-derived silica nanoparticles alter cellular metabolism in human proximal tubular kidney cells

Multiple epidemics of chronic kidney disease of an unknown etiology (CKDu) have emerged in agricultural communities around the world. Many factors have been posited as potential contributors, but a primary cause has yet to be identified and the disease is considered likely multifactorial. Sugarcane workers are largely impacted by disease leading to the hypothesis that exposure to sugarcane ash produced during the burning and harvest of sugarcane could contribute to CKDu. Estimated exposure levels of particles under 10 μm (PM10) have been found to be exceptionally high during this process, exceeding 100 μg/m3 during sugarcane cutting and averaging ∼1800 μg/m3 during pre-harvest burns. Sugarcane stalks consist of ∼80% amorphous silica and generate nano-sized silica particles (∼200 nm) following burning. A human proximal convoluted tubule (PCT) cell line was subjected to treatments ranging in concentration from 0.025 μg/mL to 25 μg/mL of sugarcane ash, desilicated sugarcane ash, sugarcane ash-derived silica nanoparticles (SAD SiNPs) or manufactured pristine 200 nm silica nanoparticles. The combination of heat stress and sugarcane ash exposure on PCT cell responses was also assessed. Following 6–48 h of exposure, mitochondrial activity and viability were found to be significantly reduced when exposed to SAD SiNPs at concentrations 2.5 μg/mL or higher. Oxygen consumption rate (OCR) and pH changes suggested significant alteration to cellular metabolism across treatments as early as 6 h following exposure. SAD SiNPs were found to inhibit mitochondrial function, reduce ATP generation, increase reliance on glycolysis, and reduce glycolytic reserve. Metabolomic analysis revealed several cellular energetics pathways (e.g., fatty acid metabolism, glycolysis, and TCA cycle) are significantly altered across ash-based treatments. Heat stress did not influence these responses. Such changes indicate that exposure to sugarcane ash and its derivatives can promote mitochondrial dysfunction and disrupt metabolic activity of human PCT cells.

Urban PM2.5 concentrations in a small Colombian city and the impact associated with particle emissions generated by small-scale lime production

The stricter guidelines for fine particles PM2.5 recently published by the World Health Organization also motivate smaller cities to assess the exposure levels. In this study, PM2.5 was assessed in the municipality of Vijes, an important lime production center in the Cauca River Valley, Colombia. The main objective was to determine PM2.5 concentration levels in the urban background of the city and to estimate the contribution from industrial sources located west of the urbanized area. The assessment of PM2.5 concentrations in a city without fixed air quality monitors, meteorological stations, and information on emission sources, was designed to be expedient and possible to perform with a very restricted budget. Four low-cost optical sensors and one low-cost meteorological station were installed during two separate campaigns, each three to four months long. The PM2.5 measurements were analyzed with the support of meteorological data and dispersion modeling. Mean levels of PM2.5 in the urban background were found to be below the Colombian limit value of 25 µg m–3, in the range of 14 to 19 µg m–3, and with lower levels in the city center. The monitor located in the westernmost urban area, closest to the industrial plants, registered a high 24-h mean level close to the national limit value. The industrial contribution to long-term PM2.5 concentrations in the urban background of Vijes was estimated to be within a maximum of 6 µg m–3, i.e., a minor fraction of the monitored PM2.5 mean levels in the urban background. The dominating part of the PM2.5 concentrations could be attributed to other anthropogenic sources within or east of Vijes, as well as originating from the regional background concentration characterizing the Cauca River Valley to the east of Vijes, where pre-harvest sugar cane burning is common.

Impact of extreme wildfires from the Brazilian Forests and sugarcane burning on the air quality of the biggest megacity on South America

Recently, extreme wildfires have damaged important ecosystems worldwide and have affected urban areas miles away due to long-range transport of smoke plumes. We performed a comprehensive analysis to clarify how smoke plumes from Pantanal and Amazon forests wildfires and sugarcane harvest burning also from interior of the state of São Paulo (ISSP) were transported and injected into the atmosphere of the Metropolitan Area of São Paulo (MASP), where they worsened air quality and increased greenhouse gas (GHG) levels. To classify event days, multiple biomass burning fingerprints as carbon isotopes, Lidar ratio and specific compounds ratios were combined with back trajectories modeling. During smoke plume event days in the MASP fine particulate matter concentrations exceeded the WHO standard (>25 μg m−3), at 99 % of the air quality monitoring stations, and peak CO2 excess were 100 % to 1178 % higher than non-event days. We demonstrated how external pollution events such as wildfires pose an additional challenge for cities, regarding public health threats associated to air quality, and reinforces the importance of GHG monitoring networks to track local and remote GHG emissions and sources in urban areas.

66 Sugarcane Ash and Sugarcane Ash-Derived Silica Nanoparticles Alter Mitochondrial Function and Metabolic Activity in Human Proximal Tubular Kidney Cells

Abstract Multiple epidemics of chronic kidney disease of an unknown etiology (CKDu), primarily in young healthy agricultural workers, have emerged in agricultural communities around the world. We have hypothesized that the harvest and burning of sugarcane leading to inhalation of sugarcane ash may contribute to development of CKDu. Sugarcane stalks consist of ~80% amorphous silica and we have demonstrated that following burning of sugarcane, nano-sized silica particles (~200nm) are generated. To determine what effect such exposures have on kidney cells, a human proximal convoluted tubule (PCT) cell line (HK-2) was subjected to treatments ranging in concentration from 0.025µg/mL to 25µg/mL of sugarcane ash, desilicated sugarcane ash, sugarcane ash-derived silica nanoparticles (SAD SiNPs), or manufactured pristine 200nm silica nanoparticles. Following 6 to 48 hours of exposure, mitochondrial activity and viability were found to be significantly reduced when exposed to SAD particles at concentrations 2.5µg/mL or higher. Oxygen consumption rate (OCR) and pH were investigated with a Seahorse XF Analyzer, revealing significant changes to cellular metabolism across treatments as early as 6 hours following exposure. While most treatments slightly increased respiration, SAD SiNPs were found to inhibit mitochondrial function, reduce ATP generation, increase reliance on glycolysis, and reduce glycolytic reserve. Metabolomic analysis following 24 hours of exposure found several cellular energetics pathways (e.g., fatty acid metabolism, glycolysis, and TCA cycle) significantly altered across ash-based treatments. Such changes indicate that exposure to sugarcane ash and its derivatives can promote mitochondrial dysfunction and disrupt metabolic activity of human PCT cells.

63 A Case for Amorphous Silica Nanoparticle Exposure in the Development of Chronic Kidney Disease of Unknown Etiology

Abstract We have hypothesized that sugarcane burning in developing countries contributes to an endemic kidney pathology in agricultural workers called chronic kidney disease of an unknown etiology (CKDu). Elemental analysis shows that sugarcane stalks contain a high percentage of amorphous silica (SiO2). Therefore, we hypothesized that burning of sugarcane generates silica nanoparticles (SiNPs) that present an inhalation hazard to these agricultural workers. To determine if SiNPs are present in sugarcane ash and kidney biopsies from agricultural workers, we utilized single particle inductively coupled plasma mass spectrometry and found SiNPs, which ranged in size from 190-212 nm, in sugarcane ash. In a small cohort of CKDu patients from El Salvador and Mexico, we found a significant increase in the number of SiNPs in their kidney biopsies within a similar size range as observed in sugarcane ash. Additionally, Wistar rats exposed to sugarcane ash intranasally for 24 weeks developed focal injury in the tubulointerstitium and glomeruli with deposition of SiNPs in the kidney. To further determine the cellular effects of SiNPs, we exposed human proximal convoluted tubule (PCT) cells to sugarcane ash, de-silicated ash, or sugarcane ash derived SiNPs. Despite not being directly cytotoxic to PCT cells at 24 hrs, SiNPs were taken up and generated reactive oxygen species. Vimentin staining confirmed PCT cells underwent epithelial-mesenchymal transition (EMT) following treatment with ash or SiNPs but not with de-silicated ash. These findings suggest SiNPs present in sugarcane ash are capable of driving EMT in PCT cells potentially contributing to a CKDu phenotype.

Characterization of Gaseous and Particulate Phase Polycyclic Aromatic Hydrocarbons Emitted During Preharvest Burning of Sugar Cane in Different Regions of Kwa-Zulu Natal, South Africa.

Biomass burning is a significant anthropogenic source of air pollution, including the preharvest burning of sugar cane. These burn events result in atmospheric emissions, including semivolatile organic compounds, that may have adverse impacts on air quality and human health on a local, regional, and even a global scale. Gaseous and particulate polycyclic aromatic hydrocarbon (PAH) emissions from various sugar cane burn events in the province of Kwa-Zulu Natal in South Africa were simultaneously sampled using a portable denuder sampling technology, consisting of a quartz fiber filter sandwiched between two polydimethylsiloxane multichannel traps. Total gas and particle phase PAH concentrations ranged from 0.05 to 9.85 µg m-3 per individual burn event, and nine PAHs were quantified. Over 85% of all PAHs were found to exist in the gas phase, with smaller two- and three-ring PAHs, primarily naphthalene, 1-methyl naphthalene, and acenaphthylene, being the most dominant and causing the majority of variance between the burn sites. The PAH profiles differed between the different burn events at different sites, emphasizing the significant influence that the crop variety, prevailing weather conditions, and geographical location has on the type and number of pollutants emitted. The potential carcinogenicity of the PAH exposure was estimated based on toxic equivalency factors that showed varying risk potentials per burn event, with the highest value of 5.97 ng m-3 . Environ Toxicol Chem 2023;42:778-792. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Correlation of Soil Physiochemical Properties, Microorganism Numbers, and Bacterial Communities Following Unburned and Burned Sugarcane Harvest

The effects on soil properties were studied following sugarcane burning during harvesting based on the analysis of soil properties and the number of microorganisms. The soil bacterial community structure was observed using metagenomics. It was found that burned sugarcane harvesting reduced the soil moisture and total nitrogen contents and decreased the numbers of bacterial fungi and actinomycetes. Furthermore, there were decreased numbers of nitrogen-fixing and phosphate-solubilizing bacteria beneficial to plants. The Firmicutes phylum (46.79%) was found abundantly in the soil after burned sugarcane harvest. Paenibacillus (34.20%) and Bacillus (9.19%) were dominant at the genus level. On the other hand, in the soil after unburned sugarcane harvest, the diversity index was higher than that after burned sugarcane harvest. Actinobacteria (25.92%) dominated at the phylum level, and Candidatus koribacter, Gaiella, Pseudolabrys, and Sphingomonas dominated at the genus level in the unburned plots. Changing the bacterial community resulted in a change in correlation with soil properties. Therefore, the impacts from burned sugarcane harvesting should be realized, specifically that soil physiochemical and biological properties are degraded (except for some groups of bacteria) along with their functions in the soil.

Behavior of geomaterial composite using sugar cane bagasse ash under compressive and flexural loading

The sugar industry produces a huge quantity of sugar cane bagasse ash in India. Dumping massive quantities of waste in a non-eco-friendly manner is a key concern for developing nations. The main focus of this study is the development of a sustainable geomaterial composite with higher strength capabilities (compressive and flexural). To develop this composite, sugarcane bagasse ash (SA), glass fiber (GF), and blast furnace slag (BF) are used. Ash generated from burning sugar cane in the sugar industry is known as sugar cane bagasse. To check the suitability of this secondary waste for use in civil engineering and to minimize risk to the environment in the development of sustainable growth, a sequence of compressive and flexural strength tests was performed on materials prepared using sugar cane bagasse ash (SA) reinforced by glass fiber (GF) in combination with blast furnace slag (BF) and cement (CEM). The effects of the mix ratios of glass fiber to bagasse ash (0.2%–1.2%), blast furnace slag to the weight of bagasse ash (10%), cement binding to bagasse ash (10%–20%), and water to sugar cane bagasse ash (55%) regarding the flexural strength, compressive strength, density, tangent modulus, stress–strain pattern, and load–deflection curve of the prepared materials were studied. According to the findings, compressive strength achieved a maximum strength of 1055.5 kPa and ranged from 120 to 1055.5 kPa, and the flexural strength achieved a maximum strength of 217 kPa and ranged from 80.1 to 217 kPa at different mix ratio percentages. The value of the initial tangent modulus for the cube specimens ranged between 96 and 636 MPa. For compression specimens with 20% cement, the density decreased from 1320.1 to 1265 kg/m3, and the flexural strength decreased from 1318 to 1259.6 kg/m3. With limitation in lower percentages of C/SA, the specimen cannot sustain its shape even after curing period. In comparing the previous research with the present experimental work, it was observed that the material proposed here is lightweight and can be utilised as a filler substance in weak compressible soils to improve their load-bearing capacity.