Pollution levels and health risk assessment of potentially toxic metals of size-segregated particulate matter in rural residential areas of high lung cancer incidence in Fuyuan, China.

The highest incidence and mortality rate of lung cancer in rural area of Fuyuan has been a research hotspot, and the pathogenesis is still unclear. Therefore, atmospheric particulate matters (APMs) samples were collected between 18 February and 01 March 2017, exploring water-soluble potentially toxic metals (WSPTMs) and water-soluble inorganic ionic species (WSIIs) levels, size distribution, sources, acidity and alkalinity, and potential carcinogenic and non-carcinogenic risks, hoping to provide scientific basic data to solve this problem. In our study, the average ratio of nitrate ion (NO3-)/sulfate ion (SO42-) within PM1.1, PM1.1-2.0, PM2.0-3.3, PM3.3-7.0, and PM>7.0 were 0.22, 0.18, 0.15, 0.34 and 0.36, respectively, that revealed that combustion sources contributed to PM were more significant. The anions in equilibrium (ANE) / cations in equilibrium (CAE) < 1 for all samples within PM1.1, PM2.0-3.3, PM3.3-7.0 indicate that the APMs were alkaline, but PM1.1-2.0 particulate matter shows weak acidity. SO42- prefers to combine with NH4+ to form (NH4)2SO4, which hinders the formation of NH4NO3, the remaining SO42- and NO3- to neutralize the K+, KNO3 was formed at all particulate, however, K2SO4 can only be formed in PM<3.3. Arsenic (As) and Selenium (Se) were identified as the most enriched WSPTMs in all PM sizes, predominantly from anthropogenic emissions, were suggested that coal combustion is a significant source of PM-bound WSPTMs. Total WSPTMs exhibited high total carcinogenic risks (TCR) values (9.98 × 10-6, 1.06 × 10-5, and 1.19 × 10-5 for girls, boys and adults, respectively) in the smaller particles (< 1.1 µm). Se was considered as the major contributor (63.60%) to carcinogenic risk (CR) in PM2.0 and had an inverse relationship with PM size that should be of prime concern.

Nutrient uptake and pharmaceutical compounds of Aloe vera as influenced by integration of inorganic fertilizer and poultry manure in soil.

Aloe vera had been used for numerous medical and cosmetic applications since ancient times. The study aimed to investigate the integrated effects of inorganic fertilizer (IF) and poultry manure (PM) on the nutritional and pharmaceutical constituents of A. vera. Eighteen month old A. vera seedlings were used following completely randomized design with three replications. Six combinations of IF [Nitrogen (N), phosphorus (P), potassium (K) and sulphur (S) at the rate of 150, 80, 120 and 30 kg ha-1, respectively] and PM (at the rate of 5 t ha-1) were considered viz., IF00PM00 (IF = 0%, PM = 0%), IF100PM00(IF = 100%, PM = 0%), IF75PM25 (IF = 75%, PM = 25%), IF50PM50 (IF = 50%, PM = 50%), IF25PM75 (IF = 25%, PM = 75%) and IF00PM100 (IF = 0%, PM = 100%) as treatments. Different treatment combinations of IF and PM exerted significant influence on the nutritional and pharmaceutical contents of A. vera. Concentrations and uptake of the concerned nutrients were gradually increased with the increased levels of PM except NPKS which were highest in sole application of IF. The aloin concentration of leaf was gradually increased with the increased level of PM and by 42.44% over control. The highest chlorophyll, total phenolic and flavonoid concentrations were found in the plants receiving the treatment IF25PM75 except protein content which was obtained from IF100PM00. Significant and positive relationships between N and S with P concentrations and P and S with K concentrations of A. vera leaf were noticed. Aloin, total phenolic and flavonoid concentrations were significantly and positively correlated with Mg, Fe and Mn concentrations of A. vera leaf. Farmers may be advised to cultivate A. vera applying 75% PM at the rate of 5 t ha-1 along with 25% IF (N, P, K and S at the rate of 150, 80, 120 and 30 kg ha-1, respectively) for obtaining better quality leaf in terms of nutrients and pharmaceutical compounds under the agro-climatic conditions of the study area.

Nitrogen use efficiency and critical leaf N concentration of Aloe vera in urea and diammonium phosphate amended soil.

Aloe vera L. is widely cultivated in many countries due to its importance as an all-purpose herbal or medicinal plant. The growth and yield of this plant can be enhanced by application of fertilizer. It is expected that a higher and balanced nutrient supply will result in higher crop production maintaining soil health, which is possible when the applied fertilizers are done in way that is efficient. So, there is a need to understand the amount of applied and type of fertilizer that will give the best output for farmers and to formulate economical market products. This study was conducted to investigate the effect of N fertilizer on leaf yield, its uptake and requirement, critical concentration, use efficiency and economics of Aloe vera L. Plants were grown at six levels of N: 0, 40, 80, 100, 150 and 200 kg ha-1 from urea and diammonium phosphate (DAP) following completely randomized design with three replicates under field condition. The highest values of yield and yield attributes and profit based on benefit cost ratio (3.81 for urea and 2.91 for DAP) were obtained with 150 kg N ha-1 (urea) and 100 kg N ha-1 (DAP). Leaf biomass yield increased by 18-128 % in urea-N and 30-139 % in DAP-N fertilized plant over control while DAP > urea by 7.59 %. Sucker production (mean number) was urea-N (4.95 Plant-1) > DAP-N (2.28 Plant-1). Both gel and leaf N concentration and uptake was highest at 200 kg ha-1 for both sources. For 80 % leaf biomass yield, minimum requirement of N was ca 74.90 (urea) and 89.60 kg ha-1 (DAP). Growth and yield parameters to N application exhibited significant and positive correlations. Critical leaf N concentration was ca 0.88% (DAP) and 0.90% (urea) while mean and maximum NUE was 34% and 64 % (urea) and 43% and 69% (DAP), respectively. Farmers can be advised to apply N at the rate of 150 kg ha-1 from urea for producing economically higher yield and better-quality A. vera leaves.

Sulphur fertilization enhanced yield, its uptake, use efficiency and economic returns of Aloe vera L.

Sulphur plays a vital role in the formation and biosynthesis of protein, chlorophyll, and few amino acids. To investigate the effect of sulphur fertilizer on leaf biomass yield, critical sulphur concentration, sulphur requirement and uptake by Aloe vera L., a pot experiment was carried out following completely randomized design with six levels of sulphur viz., 0, 15, 30, 45, 60 and 80 kg ha-1 with three replications. The results of the study revealed that the growth attributes, leaf and gel yield, and sulphur uptake significantly improved with sulphur application and the best results were obtained from the application of 45 kg sulphur ha-1. On average, addition of sulphur enhanced the leaf biomass yield by 47.5% and sulphur use efficiency by 38% compared to control. The effect of sulphur on the growth parameters and their significant and positive correlations with yield signifies the importance of sulphur on the yield and quality of A. vera. The calculated minimum amount of sulphur for 80% leaf biomass production was 21.1 kg sulphur ha-1 with a critical leaf sulphur concentration of 0.23% in A. vera. Moreover, sulphur addition to soil substantially enhanced the economic returns of A. vera. Therefore, addition of 45 kg sulphur ha-1 could be a better option for obtaining higher yield and economic return of A. vera.

Microplastics Exposure Routes and Toxicity Studies to Ecosystems: An Overview.

Microplastics (MPs) are now ubiquitous in global ecosystem, therefore all biota is at risk of exposure and potential toxicity. In this study, we presented an overview of information based on literature concerning exposure to MPs and the toxicity of such exposure. Currently, four major routes of exposure have been identified including entanglement, contact, ingestion and inhalation. Humans maybe the most exposed organism because they are at the peak of the food chain. Toxicology effect to marine and freshwater organisms are classified based on exposure dosage as either high (mortality, decreased reproductive output, organ damage) or low (changes in behavior with time). On plants, reports have shown that MPs exposure can affect negatively the growth and depending on exposure concentration and types of MPs and oxidative activities. However, effects on plants maybe short-term and transient. Although, toxicity studies regarding human are still ongoing as per reports, plants and animals are still scantly studied. Animal toxicity studies have widely used D. magna as model specie. MPs pollution may have a knock-on effect on trophic structure and functioning of ecosystems by affecting the base of the food chain. We concluded by identifying the gap in knowledge and give recommendations for future research.