Effect of particles of ashes produced from sugarcane burning on the respiratory system of rats

Health burden of sugarcane burning on agricultural workers and nearby communities

Sugarcane is the most widely cultivated crop in the world, with equatorial developing nations performing most of this agriculture. Burning sugarcane is a common practice to facilitate harvest, producing extremely high volumes of respirable particulate matter in the process. These emissions are known to have deleterious effects on agricultural workers and nearby communities, but the extent of this exposure and potential toxicity remain poorly characterized. As the epidemicof chronic kidney disease of an unknown etiology (CKDu) and its associated mortality continue to increase along with respiratory distress, there is an urgent need to investigate the causes, determine viable interventions to mitigate disease andimprove outcomes for groups experiencing disproportionate impact. The goal of this review is to establish the state of available literature, summarize what is known in terms of human health risk, and provide recommendations for what areas should be prioritized in research.

Intranasal Administration of Sugarcane Ash Causes Chronic Kidney Disease in Rats

Background. Silica nanoparticles found in sugarcane ash have been postulated to be a toxicant contributing to chronic kidney disease of unknown etiology (CKDu). However, while the administration of manufactured silica nanoparticles is known to cause chronic tubulointerstitial disease in rats, the effect of administering sugarcane ash on kidney pathology remains unknown. Here we investigate whether sugarcane ash can induce CKD in rats. Methods. Sugarcane ash was administered for 13 weeks into the nares of rats (5 mg/day for 5d/week), and blood, urine and kidney tissues were collected at 13 weeks (at the end of ash administration) and in a separate group of rats at 24 weeks (11 weeks after stopping ash administration). Kidney histology was evaluated, and inflammation and fibrosis (collagen deposition) measured. Results. Sugarcane ash exposure led to the accumulation of silica in the kidneys, lungs, liver and spleen of rats. Mild proteinuria developed although renal function was largely maintained. However, biopsies showed focal glomeruli with segmental glomerulosclerosis, and tubulointerstitial inflammation and fibrosis that tended to worsen even after the ash administration had been stopped. Staining for the lysosomal marker, LAMP-1, showed decreased staining in ash administered rats consistent with lysosomal activation. Conclusion. Sugarcane ash containing silica nanoparticles can cause CKD in rats.

Climate adaptive crop-residue management for soil-function improvement; recommendations from field interventions at two agro-ecological zones in South Asia

Utilization of biomass energy from various agricultural wastes for local usages and its removal through open burning potentially increase emission of Green House Gases (GHGs), deteriorate air-quality, formation of tropospheric ozone and create trans-boundary health hazards in countries of South East Asia. The effect of common agro-waste management practices in soil quality and agricultural production system over this part of the world is not well documented. In the present three-years long study, spanning over two entirely different agro-ecological zones of India and Bhutan, highlights the impacts of the burning of agricultural waste in soil physio-chemical properties, biological properties and crop production. The current study also focuses on the alternative usage of crop residue to enhance soil organic carbon, soil moisture, soil nutrients and soil biological activity through the application of biochar and raw agricultural waste generated from the field. It was observed that crop residue used as raw mulch and biochar improved the agricultural production up to 36%-64% over the experimental fields of India and Bhutan. The results from the study disseminated among the local farmers and technological support were provided for practicing alternative crop residue management. Nearly 1450-1500 farmers in India and 100-125 farmers in Bhutan have adopted the agro-waste management practices of removal and re-application of agro-wastes in the field. A total of ~26000 t of CO₂ emission has been reduced in two intervention sites during the study period. The present action-research helps to propose future guidelines for environmental friendly crop residue utilization and management and simultaneously help to improve agricultural yield along with soil quality.

Determination of the Area Affected by Agricultural Burning

Agricultural burning is still a common practice around the world. It is associated with the high emission of air pollutants, including short-term climate change forcing pollutants such as black carbon and PM2.5. The legal requirements to start any regulatory actions to control them is the identification of its area of influence. However, this task is challenging from the experimental and modeling point of view, since it is a short-term event with a moving area source of pollutants. In this work, we assessed this agricultural burning influence-area using the US Environmental authorities recommended air dispersion model (AERMOD). We considered different sizes and geometries of burning areas located on flat terrains, and several crops burning under the worst-case scenario of meteorological conditions. The influence area was determined as the largest area where the short-term concentrations of pollutants (1 h or one day) exceed the local air quality standards. We found that this area is a band around the burning area whose size increases with the burning rate but not with its size. Finally, we suggested alternatives of public policy to regulate this activity, which is based on limiting the burning-rate in the way that no existing households remain inside the resulting influence-area. However, this policy should be understood as a transition towards a policy that forbids agricultural burning.

Reorganization of gene network for degradation of polycyclic aromatic hydrocarbons (PAHs) in Pseudomonas aeruginosa PAO1 under several conditions

Although polycyclic aromatic hydrocarbons (PAHs) are harmful to human health, their elimination from the environment is not easy. Biodegradation of PAHs is promising since many bacteria have the ability to use hydrocarbons as their sole carbon and energy sources for growth. Of various microorganisms that can degrade PAHs, Pseudomonas aeruginosa is particularly important, not only because it causes a series of diseases including infection in cystic fibrosis patients, but also because it is a model bacterium in various studies. The genes that are responsible for degrading PAHs have been identified in P. aeruginosa, however, no gene acts alone as various stresses often initiate different metabolic pathways, quorum sensing, biofilm formation, antibiotic tolerance, etc. Therefore, it is important to study how PAH degradation genes behave under different conditions. In this study, we apply network analysis to investigating how 46 PAH degradation genes reorganized among 5549 genes in P. aeruginosa PAO1 under nine different conditions using publicly available gene coexpression data from GEO. The results provide six aspects of novelties: (i) comparing the number of gene clusters before and after stresses, (ii) comparing the membership in each gene cluster before and after stresses, (iii) defining which gene changed its membership together with PAH degradation genes before and after stresses, (iv) classifying membership-changed-genes in terms of category in Pseudomonas Genome Database, (v) postulating unknown gene’s function, and (vi) proposing new mechanisms for genes of interests. This study can shed light on understanding of cooperative mechanisms of PAH degradation from the level of entire genes in an organism, and paves the way to conduct the similar studies on other genes.