Development of a Multicomponent Microbiological Soil Inoculant and Its Performance in Sweet Potato Cultivation.

The cultivation and consumption of sweet potato (Ipomoea batatas) are increasing globally. As the usage of chemical fertilizers and pest control agents during its cultivation may lead to soil, water and air pollution, there is an emerging need for environment-friendly, biological solutions enabling increased amounts of healthy crop and efficient disease management. Microbiological agents for agricultural purposes gained increasing importance in the past few decades. Our goal was to develop an agricultural soil inoculant from multiple microorganisms and test its application potential in sweet potato cultivation. Two Trichoderma strains were selected: Trichoderma ghanense strain SZMC 25217 based on its extracellular enzyme activities for the biodegradation of plant residues, and Trichoderma afroharzianum strain SZMC 25231 for biocontrol purposes against fungal plant pathogens. The Bacillus velezensis strain SZMC 24986 proved to be the best growth inhibitor of most of the nine tested strains of fungal species known as plant pathogens, therefore it was also selected for biocontrol purposes against fungal plant pathogens. Arthrobacter globiformis strain SZMC 25081, showing the fastest growth on nitrogen-free medium, was selected as a component with possible nitrogen-fixing potential. A Pseudomonas resinovorans strain, SZMC 25872, was selected for its ability to produce indole-3-acetic acid, which is among the important traits of potential plant growth-promoting rhizobacteria (PGPR). A series of experiments were performed to test the selected strains for their tolerance to abiotic stress factors such as pH, temperature, water activity and fungicides, influencing the survivability in agricultural environments. The selected strains were used to treat sweet potato in two separate field experiments. Yield increase was observed for the plants treated with the selected microbial consortium (synthetic community) in comparison with the control group in both cases. Our results suggest that the developed microbial inoculant has the potential to be used in sweet potato plantations. To the best of our knowledge, this is the first report about the successful application of a fungal-bacterial consortium in sweet potato cultivation.

Advantages of Multiplexing Ability of the Orbitrap Mass Analyzer in the Multi-Mycotoxin Analysis.

In routine measurements, the length of the analysis time and nfumber of samples analysed during a time unit are crucial parameters, which are especially important for the food analysis, particularly in the case of mycotoxin determinations. High-resolution equipment, including time-of-flight or Orbitrap analyzators, can provide stable instrumental background for high-throughput analyses. In this report, a short, 1 min MS-based multi-mycotoxin method was developed with the application of a short column as a reduced chromatographic separation, taking advantages of the multiplexing and high-resolution capability of the QExactive Orbitrap MS possessing sub-1 ppm mass accuracy. The performance of the method was evaluated regarding selectivity, LOD, LOQ, linearity, matrix effect, and recovery, and compared to a UHPLC-MS/MS method. The final multiplexing method was able to quantify 11 mycotoxins in defined ranges (aflatoxins (corn, 2.8-600 µg/kg; wheat, 1.5-350 µg/kg), deoxynivalenol (corn, 640-9600 µg/kg; wheat, 128-3500 µg/kg), fumonisins (corn, 20-1500 µg/kg; wheat, 30-3500 µg/kg), HT-2 (corn, 64-5200 µg/kg; wheat, 61-3500 µg/kg), T-2 (corn, 10-800 µg/kg; wheat, 4-250 µg/kg), ochratoxin (corn, 4.7-600 µg/kg; wheat, 1-1000 µg/kg), zearalenone (corn, 64-4800 µg/kg; wheat, 4-500 µg/kg)) within one minute in corn and wheat matrices at the MRL levels stated by the European Union.

Comprehensive assessment of heavy elements and evaluation of potential human health risk in the urban environment: a case study from Novi Sad, Serbia.

This study aimed to determine seasonal (summer vs. winter) and spatial distribution of the selected heavy elements (HEs) (As, Cd, Co, Cr, Cu, Ni, and Pb) in soil samples collected from a typical Central European town, Novi Sad, Serbia. The highest Pb concentrations were observed in summer because of intensive ground-flushing, whereas Cu had its highest concentration in winter, which may be attributed to traffic emissions. Source characterization and spatial distribution were carried out using cluster analysis (CA), principal component analysis (PCA), variogram calculation and theoretical model fitting, GIS-based geostatistical methods, and positive matrix factorization (PMF) data processing tools. Environmental impact of HEs found in different functional areas demonstrated that the quantified concentrations of Pb, As, Co, and Cu ranked soil as unpolluted to moderately polluted, while the presence of Co, Ni, and Cr classified urban soil as moderately polluted. Pollution load index (PLI) suggested a significant HEs enrichment while the new modified approach to Nemerow integrated risk index (NIRI) indicated high risk, being extreme for some selected locations. Machine learning classifiers were used for the first time to identify the differences between urban soil and dust samples in situations when simultaneous analysis of both matrices was carried out, as well as for temporal distribution (summer versus winter), based on the obtained concentration of HEs. Variogram calculation suggested that the pattern in spatial variability within the system emerged from the combined action of key structural factors (e.g., the parent soil material, landforms and topography, and climate) and random factors related to human activities. The estimated human health risk for two segments of the population revealed that ingestion is the primary route of exposure to HEs for children and adults.

Comprehensive characterization of stress tolerant bacteria with plant growth-promoting potential isolated from glyphosate-treated environment.

The application of plant growth-promoting bacteria in agricultural systems is an efficient and environment-friendly strategy to improve crop yields and maintain soil quality. However, as different soils have diverse and specific ecological characteristics and may represent adverse abiotic conditions, in vivo application requires the careful selection of the desired beneficial microorganisms. In this study we report Ensifer adhaerens SZMC 25856 and Pseudomonas resinovorans SZMC 25875 isolates recovered from glyphosate-treated soil to possess yet undiscovered plant growth-enhancing potential. The strains were found to promote the growth of tomato seedlings significantly, to have the ability of synthesizing indole-3-acetic acid and siderophores, to tolerate pH in the range of 6.59-7.96, salinity up to 12.5 g L-1 NaCl and drought up to 125 g L-1 polyethylene glycol 6000, as well as to survive in the presence of various pesticides including glyphosate, diuron, chlorotoluron, carbendazim and thiabendazole, and heavy metals such as Al, Fe, Mn, Zn, Pb and Cu. The plant growth-promoting traits of the examined E. adhaerens and P. resinovorans isolates and their tolerance to numerous abiotic stress factors make them promising candidates for application in different agricultural environments, including soils polluted with glyphosate.

Comprehensive characterization of PAHs profile in Serbian soils for conventional and organic production: potential sources and risk assessment.

This study presents a comprehensive characterization of occurrence and levels of 16 polycyclic aromatic hydrocarbons (PAHs) in arable soils used for conventional and organic production in northern and central part of Serbia as well as cross-border region with Hungary. Furthermore, this study includes a characterization of PAH sources and carcinogenic/non-carcinogenic human health risk for PAHs accumulated in analysed arable soils. The total concentration of 16 PAHs varied between 55 and 4584 µg kg-1 in agricultural soil used for conventional production and between 90 and 523 µg kg-1 in agricultural soil used for organic production. High molecular weight (HMW) PAHs were dominant compounds with similar contribution in both soil types (86% and 80% in conventional and in organic soil, respectively). Principal component analysis and diagnostic ratios of selected PAHs were used for identification of PAH sources in the analysed soils. Additionally, positive matrix factorization was applied for quantitative assessment. The results indicated that the major sources of PAHs were vehicle emissions, biomass and wood combustion, accounting for ~ 93% of PAHs. Exposure of farmers assessed through carcinogenic (TCR) and non-carcinogenic (THQ) risk did not exceed the acceptable threshold (TCR < 10-6 and THQ < 1). Oral ingestion was the main exposure route which accounted for 57% of TCR and 80% of THQ. It was followed by dermal contact. This investigation gives a valuable data insight into the PAHs presence in arable soils and reveals the absence of environmental and health risk. It also acknowledges the importance of comprehensive monitoring of these persistent pollutants.

Pollution status and health risk caused by heavy elements in the flooded soil and vegetables from typical agricultural region in Vojvodina Province, Serbia.

The investigation conducted in the Vojvodina Province, as a typical European and one of the biggest agricultural regions in the Balkans, offers the research methodology that could be used for any non/flooded agricultural region. The flood impact on heavy elements (HE) content in the flooded arable soil (n = 16) in relation to the control soil (n = 16) was examined, as well as their accumulation in the most often cultivated vegetables (n = 96) in the studied area. Results revealed that the flood did not significantly change the pseudo total HEs concentration in the soil as well as their amounts accumulated in different soil fractions. In both soils, only the average content of Ni exceeded the maximum permissible values set by Serbian soil quality standard which is in line with the Dutch standard. In comparison with the background values, notable enrichment is found for most of analyzed elements in both soils. Soil pollution status was assessed through several indices indicating that contamination range was in the domain from a moderate to a highly polluted. The principal component analysis demonstrated that soil contamination was probably originated from agricultural/anthropogenic activities (Cd, Cu, As, Pb), apart from Ni, Cr, and Co which came from natural weathering of the parent material. Carcinogenic and non-carcinogenic risks of selected HEs for Serbian population in the investigated region were below the threshold values. The average levels of Pb in investigated potato and carrot samples were higher than the maximum allowable concentrations established by EU/Serbian regulation. The total hazard quotients (THQ) of HEs through intake of analyzed vegetables were below the safe threshold (˂ 1), suggesting the absence of adverse health effects.

Occurrence and assessment of environmental risks of endocrine disrupting compounds in drinking, surface and wastewaters in Serbia.

The present study is the first comprehensive monitoring of 13 selected endocrine disrupting compounds (EDCs) in untreated urban and industrial wastewater in Serbia to assess their impact on the Danube River basin and associated freshwaters used as sources for drinking water production in the area. Results showed that natural and synthetic estrogens were present in surface and wastewater at concentrations ranging from 0.1 to 64.8 ng L-1. Nevertheless, they were not detected in drinking water. For alkylphenols concentrations ranged from 1.1 to 78.3 ng L-1 in wastewater and from 0.1 to 37.2 ng L-1 in surface water, while in drinking water concentrations varied from 0.4 to 7.9 ng L-1. Bisphenol A (BPA) was the most abundant compound in all water types, with frequencies of detection ranging from 57% in drinking water, to 70% in surface and 84% in wastewater. Potential environmental risks were characterized by calculating the risk quotients (RQs) and the estrogenic activity of EDCs in waste, surface and drinking water samples, as an indicator of their potential detrimental effects. RQ values of estrone (E1) and estradiol (E2) were the highest, exceeding the threshold value of 1 in 60% of wastewater samples, while in surface water E1 displayed potential risks in only two samples. Total estrogenic activity (EEQt) surpassed the threshold of 1 ng E2 L-1 in about 67% of wastewater samples, and in 3 surface water samples. In drinking water, EEQt was below 1 ng L-1 in all samples.

Does the application of human waste as a fertilization material in agricultural production pose adverse effects on human health attributable to contaminants of emerging concern?

The QuEChERS (quick, easy, cheap, effective, rugged, and safe) ultrasound-assisted method was successfully used to determine the presence of contaminants of emerging concern (CECs) in both the growing medium (i.e. soil) and vegetable samples (i.e. potato, onion, celery, parsnip and carrot) cultivated in household gardens under field conditions impacted by the application of livestock manure mixed with human waste. CECs with a broad range of physico-chemical properties including pharmaceuticals, plasticizers, herbicides, personal care products, and biocides were investigated. Among all studied CECs, diclofenac (DCL), carbamazepine, bisphenol A (BPA) and estrogenic hormones (estrone (E1), 17α-ethinyl estradiol (EE2)) were detected and quantified in vegetable samples with a concentration range from 0.114 to 13.3 ng/g fresh weight (f.w.), while BPA, E1, and EE2 were detected in soil samples with concentration ranges from 0.526 to 0.830 ng/g f.w., 0.121-0.199 ng/g f.w. and 0.118-0.333 ng/g f.w., respectively. DCL was only quantified above the limit of quantification in one soil sample (0.151 ng/g f.w.). The human health risk was estimated using the threshold of toxicological concern approach and a standard diet for two segments of the population (i.e. adult and child). The consumption of investigated vegetables contaminated with CECs poses no risk for the Serbian population.

Occurrence of heavy elements in street dust from sub/urban zone of Tianjin: pollution characteristics and health risk assessment.

Main purpose of this study was to determine the concentrations of selected heavy elements (As, Cd, Pb, Cu, Co, Cr and Ni) in the street dust samples (n = 49) collected from seven districts located in suburban/urban zone of Tianjin in order to estimate their possible sources and degree of environmental pollution as well as human health risk. Mean concentrations (mg kg-1) of As (19.3), Cd (0.60), Pb (28.4) and Cu (62.7) were above their corresponding soil background values. According to the results of multivariate statistical analysis, the accumulation of As, Cd, Pb, Cu and Cr in street dust was affected by anthropogenic activities, while the contents of Ni and Co were associated with natural sources. Pollution degree by geo-accumulation index had the following trend: Cd > Cu > As > Pb > Cr > Ni > Co. Dust contamination with Cd ranged from unpolluted to highly polluted. Potential ecological risk indicated low (Pb, Cu, Cr, Co and Ni) to high (Cd) risk, while potential risk index showed moderate and very high risks. Non-carcinogenic risk of the studied elements was below safe level (<1). Data obtained in this investigation gave the additional values to the knowledge needed for future monitoring and risk assessment, relating the presence of heavy elements studied in suburban/urban areas.

Occurrence, seasonal variety of organochlorine compounds in street dust of Novi Sad, Serbia, and its implication for risk assessment.

The paper presents a study of organochlorine compounds in street dust, an often forgotten aspect of urban environmental pollution. Six different polychlorinated biphenyls (PCBs) and eighteen organochlorine pesticides (OCPs) were monitored in terms of levels, distribution, seasonal variation and health risks. Street dust samples were collected from fifteen urban locations in Novi Sad including schools, recreational areas, residential and industrial zones. Street dust concentration of PCBs ranged from less than the limit of detection (

Survey on the micro-pollutants presence in surface water system of northern Serbia and environmental and health risk assessment.

This study demonstrates the occurrence of 940 organic micro-pollutants in surface water of four rivers, one irrigation canal system, and two lakes in Vojvodina Province, the northern part of Serbia, summing in total eighteen samples. The number of detected chemicals ranged from 22 to 84, with 127 micro-pollutants detected at least once, representing 13% of the studied substances. The targeted compounds include n-alkanes, sterols, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides polychlorinated biphenyls, pesticides, pharmaceutical active compounds, industrial chemicals, plasticizers, etc. Among the analysed compounds, sterols were the most dominant with maximum quantified concentrations. The substances which were quantified with frequency over 50% were two PAHs (2-methylnaphthalene, benzo(ghi)perylene), five sterols (cholesterol, cholestanol, stigmasterol, fucosterol, beta-sitosterol), three pharmaceuticals and personal care products (L-menthol, diethyltoluamide, caffeine), and ten household chemicals (4-tert-octylphenol, dimethyl phthalate, methyl palmitate, phenylethyl alcohol, 1-nonanol, alpha-terpineol, 2-phenoxy-ethanol, methyl myristate, acetophenone, and 2-ethyl-1-hexanol). The list of priority substances under the European Union Directive 2013/39/EU includes 49 priority substances (PSs) out of which 34 were analysed. Among these, eleven PSs were quantified, and only two compounds (fluoranthene and benzo (a) pyrene) exceeded EU Environmental Quality Standards targeted values. The obtained results were compared with the previously published data that dealt with the same targeted number of micro-pollutants in sediment samples. This revealed connections between the same sampling locations. Environmental risk assessment showed the existence of potential ecological risk as 72% of the obtained values for the ecological hazard index (HI) at investigated locations were higher that the targeted value (HI > 1). Estimated values for hazard quotient (HQ) and hazard index (HI) for non-carcinogenic risk were lower than the targeted value, indicating no non-carcinogenic risk through dermal contact and non-intentional ingestion of water. Estimated values for cancer risk were all below 1 × 10-6, which is not considered to pose significant human health risk.

Seasonal, spatial variations and risk assessment of heavy elements in street dust from Novi Sad, Serbia.

This is the first study carried out to determine the levels, spatial and temporal variations and risk indices of street dust in Serbia. Sixty street dust samples representing four functional areas: school, recreational, residential and industrial were collected from Novi Sad during summer and winter. The purpose was to obtain the concentration of seven heavy elements, evaluate the possible sources and degree of environmental pollution and human health risks. The average concentration of As, Cd, Co, Cr, Cu, Ni and Pb (mg/kg) during winter was: 7.96, 0.40, 7.73, 12.1, 57.6, 14.0 and 70.6, while in summer it was: 1.88, 0.54, 4.31, 60.1, 42.7, 28.1, and 62.5, respectively. Interpolation method together with the correlation matrix and the results of multivariate statistics supported anthropogenic origin of Pb, Cr and Cu, natural origin of Ni, Cd and As and mix origin of Co. Pollution indices such as geoaccumulation index (Igeo) indicated existence of unpolluted to extreme risk regarding to environmental pollution. Moreover, the potential pollution index (Er) showed low (Pb) to moderate (Ni) risk while potential risk index (RI) and modified potential risk index (mRI) indicated considerable and very high risks. Health risk assessment showed no non-carcinogenic risk of heavy elements for adults and children.

Micro-pollutants in sediment samples in the middle Danube region, Serbia: occurrence and risk assessment.

This is the first comprehensive study on the occurrence of 940 semi-volatile organic compounds including sterols, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides, plasticizers, and other emerging compounds in 10 river and canal sediments collected in northern Serbia. For quantification of investigated compounds GC-MS-MS (selected reaction monitoring) and GC-MS (using both selected ion monitoring and total ion monitoring) methods were used. The number of detected compounds was in the range of 85-117, while the sum of the concentrations varied from 959 µg/kg dry-wt to 84,445 µg/kg dry-wt. Sterols were quantified with high frequency in nearly 100% of investigated samples suggesting that the studied rivers and canals have been contaminated by sewage. Regarding persistent organic compounds, p,p'-DDE, p,p'-DDD, and o,p'-DDT were the dominant members of organochlorine pesticides (OCPs). The concentration range of 11 quantified pesticides of 452 analyzed was from 0.564 to 61.6 µg/kg dry-wt, while the concentration range of 47 quantified PCBs of 90 analyzed was from 0.928 to 32.1 µg/kg dry-wt. OCPs (DDE, DDD, and γ-HCH) and several PAHs (fluoranthene, pyrene, phenanthrene, chrysene, benzo(a)anthracene, benzo(a)pyrene) exceeded the maximum values of the sediment quality guidelines. Contents of domestic compounds comprise a large proportion of the total contaminant concentration. Overall, the study reveals that river sediments in Vojvodina Province were moderately polluted mainly by domestic wastewater. The toxic equivalent quantity (TEQ) relative to benzo(a)pyrene and 2,3,7,8-tetrachlorodibenzodioxin for seven carcinogenic PAHs and six quantified dioxin-like PCBs ranged from 3.59 to 103 µg TEQ/kg and from 0.001 × 10-3 to 2.10 × 10-3 µg TEQ/kg, respectively, and were in the range or lower than the literature published data.

Mycotoxins, trace elements, and phthalates in marketed rice of different origin and exposure assessment.

The aim of this study was to determine levels of 11 mycotoxins, 10 trace elements, and 6 phthalates in rice samples from Serbian and Chinese market. Mycotoxins were not detected in any of the analysed rice samples. Results revealed similar median levels for following elements: Mn, 17.5 and 15.7 mg kg-1; Fe, 2.47 and 2.12 mg kg-1; Cu, 1.95 and 1.59 mg kg-1 in marketed samples from Serbia and China, respectively. Median concentration of Ni in Serbian marketed samples was 1.9 times higher than in Chinese ones. The median levels (µg kg-1) of phthalates ranged from 1.2 (benzylbutyl phthalate [BBP]) - 566 (di(2-ethyl-hexyl) phthalate [DEHP]) and 1.7 (BBP) - 348 (DEHP) in Serbian and Chinese marketed samples, respectively. The results were used to assess daily exposure of Serbian and Chinese adult consumers. The calculated target hazard quotients indicated that the potential risk attributable to the analysed contaminants in rice samples should not be of concern neither for the Serbian nor the Chinese consumers.

Polycyclic aromatic hydrocarbons in urban soil of Novi Sad, Serbia: occurrence and cancer risk assessment.

Contents of 16 polycyclic aromatic hydrocarbons were analyzed in 30 soil samples from 15 locations in Novi Sad, Serbia, assessing for the first time the corresponding health risks in the Serbian urban zone. Total concentrations were in the range of 22-2247 µg kg-1, with a mean and median value of 363 and 200 µg kg-1, respectively. Comparison with the relevant maximum allowed contents proposed by the Serbian government and with the Dutch target values implied that soils from the urban area of Novi Sad were "suitable as residential soils" and that no intervention would be needed if the current levels were retained. Seven diagnostic ratios were calculated, indicating the pyrogenic sources of PAHs as the dominant. Cancer risks in humans via accidental ingestion, inhalation of soil particles, and dermal contact with soil were estimated. Cancer risk for soil ingestion by children was the highest. The total lifetime carcinogenic risk as sum of individual cancer risks for seven carcinogenic polycyclic aromatic hydrocarbons was within the range 10-4 to 10-6, indicating acceptable risks at 30 and 47% of sites for children and adults, respectively. However, for the rest of the samples, total lifetime cancer risk was >10-4 indicating over the acceptable risk, even though the contents in soil were not of concern as the comparison with the environmental guidance previously showed. This could be explained by (a) the dominant concentrations of higher molecular weight compounds with 4 to 6 rings, among which there are compounds with higher toxicity equivalents, but also with (b) the extreme conditions used for the conservative risk assessment under maximal exposure frequency, exposure time, and ingestion rates.

Seasonal variation and health risk assessment of organochlorine compounds in urban soils of Novi Sad, Serbia.

The aim of this paper was to determine spatial and seasonal variation of 6 indicator polychlorinated biphenyls (PCBs) and 18 organochlorine pesticides (OCPs) in urban soils of Novi Sad, Serbia. Sixty surface soil samples were collected during both winter and summer season, from different types of locations: schools, recreational areas, residential and industrial zones. Samples were treated using the method of accelerated solvent extraction, which allows simultaneous extraction and clean up of PCBs and OCPs. Targeted compounds were analyzed by GC-µECD and confirmed by GC-MS. The total concentrations of studied PCBs varied from

Occurence of the phthalate esters in soil and street dust samples from the Novi Sad city area, Serbia, and the influence on the children's and adults' exposure.

This is the first study reporting the presence of 6 phthalic acid esters (PAEs) in 60 composite soil and street dust samples collected in the urban zone of Novi Sad, the second largest city in Serbia. The results were further used to assess children's and adults' PAEs nondietary daily intakes (DIs) through incidental soil and dust ingestion and/or dermal absorption. The study could be regarded as the important baseline for future monitoring of PAEs in the urban environments, particularly as it contributes to the rare data on PAEs occurence in the street dust. All 6 PAEs were detected in every analyzed soil and street dust samples from 0.0002mgkg(-1) to 4.82mgkg(-1), with the highest level obtained for di-(2-ethylhexyl) phthalate (DEHP), which was the most dominant PAE (70-96%). The highest total PAEs (Σ6PAEs) contents in soil (2.12mgkg(-1)) and street dust (5.45mgkg(-1)) samples were obtained for the samples from city parks. In all soil samples, Σ6PAEs exceeded the soil sustainable quality limit sets by the relevant Serbian Regulation, but were much lower than the limit requiring remediation measures. Concerning the estimated DIs, children were more susceptible to PAEs intake than adults regardless of the exposure routes. All the estimated DIs values were far below the known reference values.