Influence of fertilization systems to the soil inorganic compounds. Case study: monocul-tures of cereals, leguminous and oleaginous

<p>The main objective of this article is to observe the variation of the content of inorganic compounds in the soil (cobalt, selenium, barium) under the influence of fertilization systems applied to different monocultures of cereals (wheat, corn), leguminous (peas) and oleaginous (sunflower). High concentrations of cobalt, selenium and barium with phytotoxicity effect on the soil and future crops were recorded mainly in the experimental parcels cultivated with corn, respectively with sunflower and fertilized with farmyard manure. The highest phytotoxicity effect on soil and future crop was recorded in the case of cobalt, for the experimental monoculture variant of corn fertilized with farmyard manure where the cobalt concentration in the soil exceeded the alert threshold / sensitive use (AT/SU) for inorganic compounds in the soil (51.2 mg/kg d.m.).</p>

Sex differences in the link between blood cobalt concentrations and insulin resistance in adults without diabetes

Background Little is known about the effects of environmental cobalt exposure on insulin resistance (IR) in the general adult population. We investigated the association between cobalt concentration and IR. Methods A total of 1281 subjects aged more than 20 years with complete blood cobalt data were identified from the National Health and Nutrition Examination Survey (NHANES) 2015–2016 cycle. Blood cobalt levels were analyzed for their association with IR among all populations and subgroups by sex. Regression coefficients and 95% confidence intervals (CIs) of blood cobalt concentrations in association with fasting glucose, insulin and homeostatic model assessment of insulin resistance (HOMA-IR) were estimated using multivariate linear regression after adjusting for age, sex, ethnicity, alcohol consumption, body mass index, education level, and household income. A multivariate generalized linear regression analysis was further carried out to explore the association between cobalt exposure and IR. Results A negative association between blood cobalt concentration (coefficient = − 0.125, 95% CI − 0.234, − 0.015; P = 0.026) and HOMA-IR in female adults in the age- and sex-adjusted model was observed. However, no associations with HOMA-IR, fasting glucose, or insulin were found in the overall population. In the generalized linear models, participants with the lowest cobalt levels had a 2.74% (95% CI 0.04%, 5.50%) increase in HOMA-IR (P for trend = 0.031) compared with subjects with the highest cobalt levels. Restricted cubic spline regression suggested that a non-linear relationship may exist between blood cobalt and HOMA-IR. Conclusions These results provide epidemiological evidence that low levels of blood cobalt are negatively associated with HOMA-IR in female adults.

Enhancement of Cobalt Concentration Supported on Mesoporous Silica towards the Characteristics and Activities of Catalysts for the Conversion of Waste Coconut Oil into Gasoline and Diesel Oil

The analysis of the effect of cobalt concentration supported on mesoporous silica (MS) has been evaluated. This study was aimed to observe the physical and chemical characteristics of the catalysts, and also to study the catalytic activity and its selectivity towards gasoline and diesel oil products in the hydrocracking process of waste coconut oil. The MS was produced using Lapindo mud, where the CTAB was used as the mesopore templating agent. The Co/MS catalyst was prepared by the wet impregnation method with various concentrations of Co. The characterization of the catalyst includes silica purity test by XRF, determination of Co content by AAS, the crystallinity by XRD, the catalyst porosity by SAA, physical pore structure by SEM and TEM, and total acidity by the gravimetric method using NH3 base vapor adsorption. The hydrocracking was carried out in a hydrocracking reactor using various concentrations of Co/MS catalysts with the ratio of catalyst/feed = 1/50. The products of the hydrocracking process were liquid, coke, and gas. The composition of the hydrocracking liquid products was analyzed by GC-MS. Based on the results of the catalytic activity test, it was concluded that the Co(1)/MS catalyst, which had the highest acidity, showed the best catalyst selectivity towards gasoline and diesel fractions.

Evaluation of Cobalt Concentration in the Forages and Small Ruminant Blood Collected from Various Agroecological Regions

Like animals plants required nutrients for their growth and existence. Cobalt is also important element for plant and animal growth, however higher levels of Co might have toxic potential. The study was aimed to investigate Co level in samples of forages, soil, and blood plasma of sheep and goat in Bhakkar, Mianwali and Sargodha district. The results showed that district Mianwali excelled in level of Co as compared to Bhakkar and Sargodha. The factors such as bio-concentration factor and pollution load index explained the movement of cobalt along the soil-plant-animal continuum.

Sublethal Cobalt Toxicity Effects on Rainbow Trout (Oncorhynchus mykiss)

The purpose of this study was to investigate the sublethal Co toxicity on rainbow trout (Oncorhynchus mykiss). Trout were exposed to Co and selected parameters were evaluated at intervals of 1, 15 and 30 days. Fish exposed to higher levels of Co grew slower than fish exposed to lower levels of Co. Weight gain, specific growth rate (SGR) decreased linearly with the increase of cobalt in the water. The body condition factor (CF) of fish reared in water with low cobalt concentration decreased substantially but this decrease was not significant for fish exposed to higher cobalt concentration. The values of the feed conversion ratio (FCR) increased in fish exposed to higher levels of Co. Co significantly changed the activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and decreased at day 30, and in both cases this decrease was more remarkable at day 15 so that the level of AST and ALT reached the control value at day 30. The alkaline phosphatase (ALP) level also showed a remarkable 15-day decline. There was a significant increase in glucose (G) concentration in both Co-exposed groups on day 15. However, serum cholesterol (Chl) was significantly reduced on day 15 and increased on day 30; there were no significant differences in both exposed Co-groups. The triglyceride (TG) level also decreased substantially. There was no regular pattern of total protein (TP) in the serum, so that no significant differences were found in the level of TP between low and high-exposed fish. In summary, this study suggests that exposure of essential trace elements such as cobalt may change growth and biochemical parameters, and that measurement of these parameters may be used in toxicological studies to determine the general health status of fish.