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Biosolids and Dairy Shed Effluent (DSE) can contain high concentrations of plant nutrients, making them potential resources for enhancing forest tree species growth and soil fertility. This study aimed to investigate the effects of biosolids and DSE application on the growth and nutrient uptake of Leptospermum scoparium and Kunzea robusta, while also considering the potential accumulation of contaminants. The results demonstrated that amending low-fertility soil with 2600 kg N ha-1 of biosolids and 200 kg N ha-1 of DSE positively influenced the growth of both L. scoparium and K. robusta. This improvement was evident through increased biomass production and enhanced uptake of essential elements such as calcium (Ca), potassium (K), and sulfur (S). Notably, L. scoparium exhibited superior growth when combined with DSE, while both species showed similar positive responses when combined with biosolids. However, it should be noted that the application of biosolids resulted in elevated concentrations of certain trace elements in the plants, whereas DSE did not. These trace elements included cadmium (Cd), copper (Cu), manganese (Mn), and zinc (Zn). Despite the increase, the levels of these elements did not exceed unacceptable thresholds. Considering the potential influence of biosolids on plant rhizodeposition, it is recommended that future studies investigate the interactions between plant roots and microbes, particularly in relation to plant element uptake. This line of research would further enhance our understanding of the underlying mechanisms involved. In conclusion, the findings suggest that the application of biosolids and DSE can effectively improve forest tree growth and nutrient uptake. However, careful management is necessary to mitigate the potential accumulation of trace elements. These results provide valuable insights for optimizing the use of biosolids and DSE in forestry practices, with potential economic and environmental benefits.

Biosolids and Dairy Shed Effluent (DSE) can contain high concentrations of plant nutrients, making them potential resources for enhancing forest tree species growth and soil fertility. This study aimed to investigate the effects of biosolids and DSE application on the growth and nutrient uptake of Leptospermum scoparium and Kunzea robusta, while also considering the potential accumulation of contaminants. The results demonstrated that amending low-fertility soil with 2600 kg N ha-1 of biosolids and 200 kg N ha-1 of DSE positively influenced the growth of both L. scoparium and K. robusta. This improvement was evident through increased biomass production and enhanced uptake of essential elements such as calcium (Ca), potassium (K), and sulfur (S). Notably, L. scoparium exhibited superior growth when combined with DSE, while both species showed similar positive responses when combined with biosolids. However, it should be noted that the application of biosolids resulted in elevated concentrations of certain trace elements in the plants, whereas DSE did not. These trace elements included cadmium (Cd), copper (Cu), manganese (Mn), and zinc (Zn). Despite the increase, the levels of these elements did not exceed unacceptable thresholds. Considering the potential influence of biosolids on plant rhizodeposition, it is recommended that future studies investigate the interactions between plant roots and microbes, particularly in relation to plant element uptake. This line of research would further enhance our understanding of the underlying mechanisms involved. In conclusion, the findings suggest that the application of biosolids and DSE can effectively improve forest tree growth and nutrient uptake. However, careful management is necessary to mitigate the potential accumulation of trace elements. These results provide valuable insights for optimizing the use of biosolids and DSE in forestry practices, with potential economic and environmental benefits. [ABSTRACT FROM AUTHOR]

The application of biosolids to agricultural land has been identified as a major pathway of microplastic (MP) pollution to the environment. Very little research, however, has been done on the MP content of biosolids within Canada. Fifteen biosolid samples from different treatment processes (liquid, dewatered, pelletized, and alkali‐stabilized) were collected from 11 sources across southern Ontario to quantify and characterize the MP load within them. All samples exhibited MP concentrations ranging from 188 200 (±24 161) to 512 000 (±28 571) MPs/kg dry weight and from 4122 (±231) to 453 746 (±38 194) MPs/kg wet weight. Field amendment of these biosolids can introduce up to 3.73 × 106 to 4.12 × 108 MP/ha of agricultural soil. There was no significant difference in the MP concentrations of liquid, dewatered, and pelletized samples; but a reduction in MP content was observed in alkali‐stabilized biosolids. Fragments composed 57.6% of the MPs identified, while 36.7% were fibers. In addition, MPs showed an exponential increase in abundance with decreasing size. Characterization of MPs confirmed that polyester was the most abundant, while polyethylene, polypropylene, polyamide, polyacrylamide, and polyurethane were present across the majority of biosolid samples. The results of the present study provide an estimate of the potential extent of MP contamination to agricultural fields through the amendment of biosolids. Environ Toxicol Chem 2024;43:793–806. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

• Directions for future research of sustainable use of biosolids as a N source. • Global biosolids regulations and common biosolids treatment methods are discussed. • Higher total N content in HDB and reduced N availability from CB are reported. • Key factors in biosolids treatment affecting biosolids properties are identified. • Existing models of soil N dynamics after biosolids application are summarized. Application of biosolids to agricultural land has gained increasing attention due to their rich nutrient content. There are a variety of treatment processes for converting sewage sludge to biosolids. Different treatment processes can change the physicochemical properties of the raw sewage sludge and affect the dynamics of nutrient release in biosolids-amended soils. This paper reviews heat drying, alkaline treatment, and composting as biosolids treatment processes and discusses the effects of these treatments on biosolid nitrogen (N) content and availability. Most N in the biosolids remain in organic forms, regardless of biosolids treatment type but considerable variation exists in the mean values of total N and mineralizable N across different types of biosolids. The highest mean total N content was recorded in heat-dried biosolids (HDB) (4.92%), followed by composted biosolids (CB) (2.25%) and alkaline-treated biosolids (ATB) (2.14%). The mean mineralizable N value was similar between HDB and ATB, with a broader range of mineralizable N in ATB. The lowest N availability was observed in CB. Although many models have been extensively studied for predicting potential N mineralization in soils amended with organic amendments, limited research has attempted to model soil N mineralization following biosolids application. With biosolids being a popular, economical, and eco-friendly alternative to chemical N-fertilizers, understanding biosolids treatment effects on biosolids properties is important for developing a sound biosolids management system. Moreover, modeling N mineralization in biosolids-amended soils is essential for the adoption of sustainable farming practices that maximize the agronomic value of all types of biosolids. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a highly toxic metal, occurring in municipal wastewater and stormwater as well as in wastewater from various industries. Char derived from the pyrolysis of municipal sewage sludge has the potential to be a low-cost sorption media for the removal of Cd. However, the balance between possible local char production and demand has not been assessed previously. In this study, the Cd sorption capacities of chars derived from primary (PSC) and secondary sludge (DSC), as well as the feasibility of char production for Cd sorbent purposes, and the pyrolysis energy balance were evaluated. Results showed that the sorption capacity of PSC (9.1 mg/g; 800 °C, 70 min) was superior to that of DSC (6.0 mg/g; 800 °C, 70 min), and increased with a higher pyrolysis temperature. Pyrolysis of primary sludge had a more favourable energy balance compared with the pyrolysis of digested sludge; however, when accounting for loss of biogas production the energy balance of primary sludge pyrolysis was negative. Assessment of the regional demand (Västerås, Sweden) indicated that PSC or DSC may cover the local Cd sorbent demand. However, it was estimated that large char volumes would be required, thus making the use of DSC/PSC less feasible. HIGHLIGHTS Char derived from the pyrolysis of municipal sewage sludge is a potential low-cost technology for Cd removal.; Char derived from primary sludge showed superior sorption capacity compared to char derived from mixed digested sludge.; Theoretical calculations indicated a potentially positive energy balance of digested sludge pyrolysis.; Locally, sludge pyrolysis may not be motivated by Cd sorbent production alone.;

Increasingly stringent limits on nutrient discharges are motivating water resource recovery facilities (WRRFs) to consider the implementation of sidestream nutrient removal or recovery technologies. To further increase biogas production and reduce landfilled waste, WRRFs with excess anaerobic digestion capacity can accept other high-strength organic waste (HSOW) streams. The goal of this study was to characterize and evaluate the life-cycle global warming potential (GWP), eutrophication potential, and economic costs and benefits of sidestream nutrient management and biosolid management strategies following digestion of sewage sludge augmented by HSOW. Five sidestream nutrient management strategies were analyzed using environmental life-cycle assessment (LCA) and life-cycle cost analysis (LCCA) for codigestion of municipal sewage sludge with and without HSOW. As expected, thermal stripping and ammonia stripping were characterized by a much lower eutrophication potential than no sidestream treatment; significantly higher fertilizer prices would be needed for this revenue stream to cover the capital and chemical costs. Composting all biosolids dramatically reduced the GWP relative to the baseline biosolid option but had slightly higher eutrophication potential. These complex environmental and economic tradeoffs require utilities to consider their social, environmental, and economic values in addition to present or upcoming nutrient discharge limits prior to making decisions in sidestream and biosolids management.

AbstractPharmaceuticals and personal care products are toxic chemicals which are widespread primarily due to wastewater application and its treatment processes. Biosolids are treated organic end products produced during wastewater treatment. Biosolids are applied in agriculture soils to increase productivity after meeting regulatory directives. However, biosolids have been documented to contain pharmaceuticals and personal care products during wastewater treatment process. Land application of biosolids has the potential to transfer these contaminants into soil-vegetable system leading to potential health risk. Hence, effective management of biosolids is necessary for its land application with minimal contamination risks. For this, biochar application has gained interest in recent years. Biochar amendment can help in managing pharmaceutical and personal care product contamination. Biochar derived through pyrolysis of biosolids can be an effective alternative to reduce contamination through direct biosolid application. This review gives an overview of important pharmaceuticals and personal care products spread due to biosolid amendment in soil and highlights their contamination in soil-vegetable system. An insight into their accumulation in soil-vegetable system, the translocation and risk assessment studies have been investigated. Lastly, the management of these contaminants through biochar application along with research gaps and future perspectives is discussed. [ABSTRACT FROM AUTHOR]

Over recent decades, an extensive array of anthropogenic chemicals have entered the environment and have been implicated in the increased incidence of an array of diseases, including metabolic syndrome. The ubiquitous presence of these environmental chemicals (ECs) necessitates the use of real‐life exposure models to the assess cumulative risk burden to metabolic health. Sheep that graze on biosolids‐treated pastures are exposed to a real‐life mixture of ECs such as phthalates, per‐ and polyfluoroalkyl substances, heavy metals, pharmaceuticals, pesticides, and metabolites thereof, and this EC exposure can result in metabolic disorders in their offspring. Using this model, we evaluated the effects of gestational exposure to a complex EC mixture on plasma triglyceride (TG) concentrations and metabolic and epigenetic regulatory genes in tissues key to energy regulation and storage, including the hypothalamus, liver, and adipose depots of 11‐month‐old male offspring. Our results demonstrated a binary effect of EC exposure on gene expression particularly in the hypothalamus. Principal component analysis revealed two subsets (B‐S1 [n = 6] and B‐S2 [n = 4]) within the biosolids group (B, n = 10), relative to the controls (C, n = 11). Changes in body weight, TG levels, and in gene expression in the hypothalamus, and visceral and subcutaneous fat were apparent between biosolid and control and the two subgroups of biosolids animals. These findings demonstrate that gestational exposure to an EC mixture results in differential regulation of metabolic processes in adult male offspring. Binary effects on hypothalamic gene expression and altered expression of lipid metabolism genes in visceral and subcutaneous fat, coupled with phenotypic outcomes, point to differences in individual susceptibility to EC exposure that could predispose vulnerable individuals to later metabolic dysfunction. [ABSTRACT FROM AUTHOR]

This perspective is an overview of the recent advances in teeth microcrack (MC) research, where there is a clear tendency towards a shift from two-dimensional (2D) to three-dimensional (3D) examination techniques, enhanced with artificial intelligence models for data processing and image acquisition. X-ray micro-computed tomography combined with machine learning allows 3D characterization of all spatially resolved cracks, despite the locations within the tooth in which they begin and extend, and the arrangement of MCs and their structural properties. With photoluminescence and micro-/nano-Raman spectroscopy, optical properties and chemical and elemental composition of the material can be evaluated, thus helping to assess the structural integrity of the tooth at the MC site. Approaching tooth samples having cracks from different perspectives and using complementary laboratory techniques, there is a natural progression from 3D to multi-modal imaging, where the volumetric (passive: dimensions) information of the tooth sample can be supplemented by dynamic (active: composition, interaction) image data. Revelation of tooth cracks clearly shows the need to re-assess the role of these MCs and their effect on the structural integrity and longevity of the tooth. This provides insight into the nature of cracks in natural hard materials and contributes to a better understanding of how bio-inspired structures could be designed to foresee crack propagation in biosolids. [ABSTRACT FROM AUTHOR]

Agricultural soils are degraded worldwide as result of anthropogenic activities; environmental contamination; and excessive use of chemicals, fertilizers, and pesticides. Scientists are concerned about this problem; during the past few years sewage compost and sludge have been used as alternatives to improve the soil's physical and chemical characteristics. Recycling solid waste residues can be a cost-effective way to reduce landfill material disposal and improve macro and micronutrients' availability in agricultural soils. In this study, two types of biosolids (compost and sludge) were added to tropical soils (coloso and voladora series) to improve the nutritional content in two edible herbs (basil and coriander). Soil mixtures were made by volume percentage; compost was constant, at 25%, and soil and sludge were incorporated in different proportions to complete the 100% (25 comp/75 soil, 25 comp/62.5 soil/12.5 sludge, 25 comp/50 soil/25 sludge and 25 comp/37.5 soil/37.5 sludge). pH and electrical conductivity were measured in soil mixtures. Basil and coriander were cultivated in pots for 30 days at an open greenhouse (5 replicates per soil mixtures). Germination percentage, stems' length, total chlorophyll (SPAD 502), acid digestions of plant tissues and an ICP-OES analysis were performed for both plants cultivated in all the soil mixtures. In voladora soil, the pH increased from 4.55 ± 0.10 to 5.64 ± 0.22 and EC from 0.0563 ± 0.0003 dS/m to 1.39 ± 0.01 dS/m in a 25% comp/37.5% soil/37.5% sludge mixture. In the coloso soil, the pH increased from 6.38 ± 0.13 to 6.82 ± 0.07 and electrical conductivity from 0.117 ± 0.001 to 1.310 ± 0.009 dS/m in 25% compost/37.5% soil/37.5% sludge mixture. Significant differences (p < 0.05) were found in the chlorophyll content and stem length for both plants. The highest chlorophyll value was in basil leaves from a 25% compost/50% soil/25% sludge mixture (43.20 ± 074) compared to the coloso soil (26.99 ± 0.43). In the voladora soil, the highest chlorophyll content was in a 25% compost/37.5% soil/37.5% sludge mixture (39.97 ± 0.83). In coriander leaves, the highest chlorophyll content was 33.01 ± 0.84 in the 25% compost/62.5% coloso/12.5% sludge mixture. In the voladora soil, chlorophyll content in leaves did not show a significant difference between treatments. Larger basil stems were found at 25% compost/75% voladora mixture (17.50 ± 2.39 cm) and in a 25% compost/62.5% coloso/12.5% sludge mixture (9.95 ± 0.71 cm) compared to control plants (3.45 ± 0.18 cm). Greater coriander stems were observed in a 25% compost/50% voladora/25% sludge mixture (2.43 ± 0.11 cm) and in a 25% compost/50% coloso/25% sludge mixture (2.17 ± 0.10 cm) compared to control plants (2.05 ± 0.07 cm). Macro and micronutrient content in plants increased with biosolids' incorporation to soils. Mg content in basil leaves increased from 8.61 ± 0.70 mg/g in the voladora soil to 10.31 ± 0.60 mg/g in a 25% compost/37.5% soil/37.5% sludge mixture. In coriander leaves, Mg increased from 6.91 ± 0.06 mg/g in a 25% compost/75% soil mixture to 9.63 ± 0.02 mg/g in a 25% compost/50% soil/25% sludge mixture. The Mn uptake by basil leaves increased from 0.076 ± 0.005 mg/g in the coloso soil to 0.152 ± 0.019 mg/g in a 25% compost/75% soil mixture. In coriander leaves, Mn increased from 0.357 ± 0.002 mg/g in a 25% compost/75% soil mixture to 0.651 ± 0.006 mg/g in a 25% compost/37.5% soil/37.5% sludge mixture. [ABSTRACT FROM AUTHOR]

Biosolids have benefits for soil and crop production and contribute to sustainable development. The use of biosolids in agriculture holds great potential for enhancing the economic development of rural communities. This research aims to analyze the mediating role of attitudes between knowledge and the intention to use biosolids as fertilizer. During the examination process 635 questionnaires were obtained, and statistical analysis was performed using Smart-PLS. The results of the study indicate that attitudes play a mediating role between knowledge and the intention to use biosolids in agriculture. In conclusion, it is emphasized in the need for positive attitudes towards the use of biosolids among agricultural managers, directors, technicians, and farmers. These results benefit the Dominican Republic's Ministry of Agriculture, agricultural professionals, and farmers. The Ministry can shape policies and offer education on biosolid use. Agricultural leaders should consider attitudes alongside knowledge.Farmers should stay informed and adopt biosolid practices for better crop productivity and soil health.

Sludge is a by-product of urban wastewater treatment plants using a biological method, which needs to be properly processed and managed in order to avoid environmental pollution and maintain the health of society. The main goal of the current research is to analyze the amounts of sludge disposal and energy recovery in the wastewater treatment plant in south of Tehran, emphasizing the nexus between carbon and energy footprints. Biogas and electricity produced in the wastewater treatment plant were carefully examined. Their impact on reducing direct and indirect emissions and carbon footprint was calculated using relevant international coefficients based on the amount of methane gas and electricity produced. Also, the amount of waste sludge was analyzed during the period of eight years (2014 to 2021). During the investigated period, at least 2414 tons, maximum 22850 tons and an average of 7265.4 tons of sewage sludge were produced per month. The amount of waste sludge produced per million cubic meters of treated wastewater is 24.4, 99.8 and 57.1 tons, respectively. On average, 9.5 million m3 of methane are produced every year, which is equivalent to 146347.54 tons of CO2/ year. On average, 1.1 MW/hr is produced in the power plant of the treatment plant, which is equivalent to preventing the emission of 3612 to 6472 tons of CO2/ year. The total direct and indirect emissions prevented are equal to 149,960 to 152,820 tons of CO2 equivalent. The production of biogas and its consumption to produce electricity in the investigated wastewater treatment plant has a significant effect on reducing greenhouse gas emissions.

This review examines the economic impact of Latin American regulations, strategies, and community involvement in mitigating the detrimental effects of mismanaged municipal domestic wastewater on public health, safety, and the economy. A systematic review and meta-analysis are conducted to assess the economic potential of reclaimed water in the region, utilizing various data sources and methodologies. The findings reveal that Latin America faces challenges in wastewater treatment, regulation, and resource management, affecting the market potential of reclaimed water. However, resource recovery initiatives present economic opportunities, including cost reduction, agricultural growth, energy recovery, and resource reuse.The study also highlights the lack of sanitation and wastewater treatment coverage data in many Latin American countries. By examining the commercial possibilities, regulatory frameworks, and environmental benefits of reclaimed water, this research provides valuable insights for sustainable water management and resource recovery policymakers, practitioners, and researchers. Furthermore, it emphasizes the economic advantages of utilizing reclaimed water and biosolids in Latin America, advocating for the implementation of strong regulations and policies to promote job creation and economic growth.

Abstract Background Over 40% of the six million dry metric tons of sewage sludge, often referred to as biosolids, produced annually in the United States is land applied. Biosolids serve as a sink for emerging pollutants which can be toxic and persist in the environment, yet their fate after land application and their impacts on human health have not been well studied. These gaps in our understanding are exacerbated by the absence of systematic monitoring programs and defined standards for human health protection. Methods The purpose of this paper is to call critical attention to the knowledge gaps that currently exist regarding emerging pollutants in biosolids and to underscore the need for evidence-based testing standards and regulatory frameworks for human health protection when biosolids are land applied. A scoping review methodology was used to identify research conducted within the last decade, current regulatory standards, and government publications regarding emerging pollutants in land applied biosolids. Results Current research indicates that persistent organic compounds, or emerging pollutants, found in pharmaceuticals and personal care products, microplastics, and per- and polyfluoroalkyl substances (PFAS) have the potential to contaminate ground and surface water, and the uptake of these substances from soil amended by the land application of biosolids can result in contamination of food sources. Advanced technologies to remove these contaminants from wastewater treatment plant influent, effluent, and biosolids destined for land application along with tools to detect and quantify emerging pollutants are critical for human health protection. Conclusions To address these current risks, there needs to be a significant investment in ongoing research and infrastructure support for advancements in wastewater treatment; expanded manufacture and use of sustainable products; increased public communication of the risks associated with overuse of pharmaceuticals and plastics; and development and implementation of regulations that are protective of health and the environment.

The purpose of this investigation was to verify the effectiveness of composting in the sanitization of sludge from urban sewage (SS). The treatments (T) used consisted of SS mixed with sugarcane bagasse (SB), tree pruning residues (TP), poultry litter (PL) or grass clipping (GC) at a carbon/nitrogen ratio of approximately 30/1 and ratios of T1 (SS+SB), T2 (SS+SB+TP), T3 (SS+SB+GC), T4 (SS+SB+PL) or T5 (SS+SB+TP+GC). Temperature was measured daily for over 280 days of composting. Every two weeks, the compounds were analyzed for thermotolerant coliforms and viable helminth eggs using the multiple-tube and Yanko techniques; and once each month to identify Cryptosporidium spp. and Giardia spp. (oo)cysts using the sucrose and zinc sulfate centrifugal flotation technique and nested PCR followed by sequencing. The maximum temperatures measured in the thermophilic phase of the compounds ranged from 55°C to 64.8°C, and at day 280, weight reductions of 27% (T1), 48% (T2), 63% (T3), 66% (T4) and 64% (T5) were observed. The absence of fecal coliforms was observed from day 98 (T4), day 126 (T1), day 196 (T3 and T5) and day 210 (T2). All treatments resulted in helminth egg inviability and the absence of protozoan (oo)cysts. Only T4 and T5 were positive for G. duodenalis according to the sequencing analysis. In conclusion, high temperatures during the composting thermophilic phase made the use of pathogens required by legislation unfeasible; therefore, it is important to investigate the viability of protozoa in compounds to ensure a safe final product for human and animal health.

Background: Sewage sludge is rich in fecal coliforms, Salmonella, parasite eggs, and heavy metals that can cause disease in humans. The aim of this study was to evaluate the quality of outlet biosolids and sludge heavy metals in the wastewater treatment plants (WWTP) in Mazandaran province and to compare them with the Environmental Protection Agency (EPA) standards. Methods: This study was carried out on the sludge of the treatment plants of Sari, Joybar, Babol, Babolsar, Nowshahr, and Nowshahr-Chalus sludge compost plants. In this study, physical, chemical, and biological properties of sludge samples including retention time, pH, total solids (TS), color, heavy metals (copper, zinc, nickel, cadmium, and chromium) as well as the density of fecal coliform, Salmonella and parasite eggs were determined and reported. Results: Biosolids of Joybar, Babol, Babolsar, and Nowshahr-Chalus WWTP in terms of parasite eggs were in class A. Biosolids of Sari WWTP in summer after drying off naturally were located in Class A, and in summer and spring, were located in Class B based on the US EPA criteria. The average concentration of heavy metals (copper, zinc, nickel, cadmium, and chromium) was lower than the EPA standard. Conclusion: The results showed that mostly the treated sewage sludge in Mazandaran WWTPs were in Class B of the EPA guideline. The concentration of heavy metals in the biosolids of these WWTPs is lower than the EPA regulation and the use of these biosolids in agriculture is not limited for these metals.

Agricultural soils are degraded worldwide as result of anthropogenic activities; environmental contamination; and excessive use of chemicals, fertilizers, and pesticides. Scientists are concerned about this problem; during the past few years sewage compost and sludge have been used as alternatives to improve the soil’s physical and chemical characteristics. Recycling solid waste residues can be a cost-effective way to reduce landfill material disposal and improve macro and micronutrients’ availability in agricultural soils. In this study, two types of biosolids (compost and sludge) were added to tropical soils (coloso and voladora series) to improve the nutritional content in two edible herbs (basil and coriander). Soil mixtures were made by volume percentage; compost was constant, at 25%, and soil and sludge were incorporated in different proportions to complete the 100% (25 comp/75 soil, 25 comp/62.5 soil/12.5 sludge, 25 comp/50 soil/25 sludge and 25 comp/37.5 soil/37.5 sludge). pH and electrical conductivity were measured in soil mixtures. Basil and coriander were cultivated in pots for 30 days at an open greenhouse (5 replicates per soil mixtures). Germination percentage, stems’ length, total chlorophyll (SPAD 502), acid digestions of plant tissues and an ICP-OES analysis were performed for both plants cultivated in all the soil mixtures. In voladora soil, the pH increased from 4.55 ± 0.10 to 5.64 ± 0.22 and EC from 0.0563 ± 0.0003 dS/m to 1.39 ± 0.01 dS/m in a 25% comp/37.5% soil/37.5% sludge mixture. In the coloso soil, the pH increased from 6.38 ± 0.13 to 6.82 ± 0.07 and electrical conductivity from 0.117 ± 0.001 to 1.310 ± 0.009 dS/m in 25% compost/37.5% soil/37.5% sludge mixture. Significant differences (p < 0.05) were found in the chlorophyll content and stem length for both plants. The highest chlorophyll value was in basil leaves from a 25% compost/50% soil/25% sludge mixture (43.20 ± 074) compared to the coloso soil (26.99 ± 0.43). In the voladora soil, the highest chlorophyll content was in a 25% compost/37.5% soil/37.5% sludge mixture (39.97 ± 0.83). In coriander leaves, the highest chlorophyll content was 33.01 ± 0.84 in the 25% compost/62.5% coloso/12.5% sludge mixture. In the voladora soil, chlorophyll content in leaves did not show a significant difference between treatments. Larger basil stems were found at 25% compost/75% voladora mixture (17.50 ± 2.39 cm) and in a 25% compost/62.5% coloso/12.5% sludge mixture (9.95 ± 0.71 cm) compared to control plants (3.45 ± 0.18 cm). Greater coriander stems were observed in a 25% compost/50% voladora/25% sludge mixture (2.43 ± 0.11 cm) and in a 25% compost/50% coloso/25% sludge mixture (2.17 ± 0.10 cm) compared to control plants (2.05 ± 0.07 cm). Macro and micronutrient content in plants increased with biosolids’ incorporation to soils. Mg content in basil leaves increased from 8.61 ± 0.70 mg/g in the voladora soil to 10.31 ± 0.60 mg/g in a 25% compost/37.5% soil/37.5% sludge mixture. In coriander leaves, Mg increased from 6.91 ± 0.06 mg/g in a 25% compost/75% soil mixture to 9.63 ± 0.02 mg/g in a 25% compost/50% soil/25% sludge mixture. The Mn uptake by basil leaves increased from 0.076 ± 0.005 mg/g in the coloso soil to 0.152 ± 0.019 mg/g in a 25% compost/75% soil mixture. In coriander leaves, Mn increased from 0.357 ± 0.002 mg/g in a 25% compost/75% soil mixture to 0.651 ± 0.006 mg/g in a 25% compost/37.5% soil/37.5% sludge mixture.

Biosolids have benefits for soil and crop production and contribute to sustainable development. The use of biosolids in agriculture holds great potential for enhancing the economic development of rural communities. This research aims to analyze the mediating role of attitudes between knowledge and the intention to use biosolids as fertilizer. During the examination process 635 questionnaires were obtained, and statistical analysis was performed using Smart-PLS. The results of the study indicate that attitudes play a mediating role between knowledge and the intention to use biosolids in agriculture. In conclusion, it is emphasized in the need for positive attitudes towards the use of biosolids among agricultural managers, directors, technicians, and farmers. These results benefit the Dominican Republic's Ministry of Agriculture, agricultural professionals, and farmers. The Ministry can shape policies and offer education on biosolid use. Agricultural leaders should consider attitudes alongside knowledge. Farmers should stay informed and adopt biosolid practices for better crop productivity and soil health. [ABSTRACT FROM AUTHOR]

[Display omitted] • Slow pyrolysis of sewage sludge (SS) was conducted at an industrial pilot scale. • The effect of pyrolysis on 161 organic contaminants in SSs was studied. • Pyrolysis temperature of >500 °C is advised for organic contaminant removal. • Pyrolysis is suitable for SSs with moderate inorganic contaminant levels. • Industrial scale results were mostly in line with published laboratory scale data. Pyrolysis has been gaining global interest as a viable option for reducing organic contaminant levels in waste materials such as sewage sludge (SS) for their subsequent use as a soil amendment. However, publicly available knowledge on the capacity of pyrolysis to reduce the levels in SSs is mostly based on laboratory or bench scale studies. The aim of this study was to examine the effects of industrial pilot scale slow pyrolysis at two temperatures and retention times (450 °C, 1 h and 500 °C, 1.5 h) on a wide range of organic and inorganic contaminants in SSs. Pyrolysis at 500 °C decreased the concentrations of the detected per- and polyfluoroalkyl substances (PFASs, by 30–93 %), brominated diphenyl ethers (BDEs; by 97–98 %) and most endocrine disrupting compounds (EDCs, by 82–96 %) more efficiently than pyrolysis at 450 °C. Estrone and pharmaceuticals, with the exception of paracetamol, were removed to below quantification limits. Non-volatile inorganic contaminants concentrated to the chars (22–46 % increase). These results confirm that slow pyrolysis has the capacity to significantly reduce organic contaminant levels in SSs at an industrial scale, while content of inorganic contaminants depends mainly on the feedstock properties. Pyrolysis temperature of over 500 °C is advised to secure efficient removal of organic contaminants. However, it is anticipated that reactor design with good heat transfer and volatile removal could further improve the removal of organic contaminants from SSs. The results are especially valuable for sludge management operators planning to procure a pyrolysis plant. [ABSTRACT FROM AUTHOR]

Sewage sludge contains plant nutrients and organic matter in its composition, making it a potential partial substitute for mineral fertilizers if it meets environmental, agronomic, and sanitary standards. The objective was to evaluate the content of nutrients and heavy metals in the sludge generated in four wastewater treatment stations (WWTPs) in Rio de Janeiro state and assess its potential value and usefulness. The samples of 19 batches from the WTTPs Alegria, Barra da Tijuca, Ilha do Governador, and Sarapuí were analyzed. The WWTPs differ in methods and processes used for treating sewage and sludge. The total contents of C, N, P, K, Ca, Mg, Fe, Al, Na, Co, Mn, As, Ba, Cd, Cr, Cu, Ni, Se, Pb, and Zn were evaluated, as well as the ratio C/N, pH, organic matter content, and electrical conductivity. The grouping of sludge samples was assessed using principal components (PCA) and cluster analysis. The economic valuation of sludge was conducted utilizing the substitute goods method, which compared the sludge's N-P-K contents with the prices of consolidated nutrient sources. All the evaluated sludge batches exhibited concentrations of heavy metals below the limits allowed by Brazilian law, along with high levels of nutrients and organic matter. Considering the chemical characteristics, all evaluated materials showed potential for agricultural use, but it is crucial to evaluate the microbiological characteristics of sludge batches before agriculture application. PCA and cluster analysis demonstrated that sludge samples from the same WWTP clustered close to each other, demonstrating higher similarity among themselves than with samples from other WWTPs. The sludge had an average added value of U$ 88.46 per megagram, considering the total contents of N, P, and K in its composition. Land application of sewage sludge can reduce the need to purchase mineral fertilizers, thereby supporting the feasibility of reusing this material in the agricultural sector. [ABSTRACT FROM AUTHOR]

Biobased residues are local and cost-effective sources of soil amendments that can efficiently provide nutrients to crops, enhance soil health and serve as alternatives to mineral fertilizers. The objective of our study was to comprehensively evaluate the soil health and crop productivity of temperate agroecosystems amended with different types of organic residues (biobased residues), including composted food waste (compost), biosolid slurry (biosolids) and liquid anaerobic digestate (digestate), compared with nitrogen fertilizer. The experiment was conducted on a silt loam soil under maize-soybean rotation in Canada, where a wide range of physical, chemical and biological indicators were measured and integrated into a soil health score. Biobased residues resulted in about 50%-60% increase in soil-exchangeable potassium and 10% soil-exchangeable sodium over levels found in nitrogen fertilizer. Soil microbial biomass and the capacity of soil microbes to utilize carbon substrates differed among growing seasons but not among amendment types (p > .05). Crop productivity was similar among amendment types (p > .05). We found that the soil health score of biosolids was positively correlated with shoot and root biomass and negatively correlated with shoot nitrogen (p < .05), while that of nitrogen fertilizer was positively correlated with shoot carbon (p < .05). This was likely because of a variation in the availability of labile carbon and nitrogen among amendment types. Our research also suggests that temperate silt loam soil amended with biobased residues, especially biosolids, supplied sufficient nitrogen without the need for additional nitrogen fertilizer. [ABSTRACT FROM AUTHOR]

Sewage sludge in natura is rich in nutrients, water, and organic matter and is essential for plant development. However, sewage sludge is diluted with water when composted, which could hamper plant growth. Therefore, supplementation with chemical fertilization may be necessary. This study evaluated the performance of composted sewage sludge (CSS) in producing Peltophorum dubium (Spreng.) Taub. seedlings with and without chemical fertilization via fertigation. The experiment was completely randomized in a 3 × 4 factorial scheme, with four fertigation (Ca(NO3)2(H2O)x: 0.87; (NH4)(H2PO4): 0.21; KCl: 0.47; (NH4)2SO4: 0.11; CH₄N₂O: 0.54; MgSO4: 0.52; Fe (13%): 0.03; B(OH)3: 6.00; CuSO4: 0.60; ZnSO4: 1.40; MnSO4: 6.00; Na2MoO4: 0.16 g L−1) doses: zero, standard, duplicate, and quadruplicate. In addition, three substrates were used: commercial substrate as the control, sewage sludge composted with sugarcane bagasse (LBC), and sewage sludge composted with Eucalyptus bark (LCE). The development of the seedlings was measured through the following variables: height, stem diameter, shoot/root ratio, leaf dry mass, root dry mass, total dry mass, green color index, the Dickson Quality Index, and the accumulation of nutrients in plant tissue. The seedlings produced with LCE that were subjected to the standard dose (1×) and the quadruplicate dose (4×) had the statistically highest mean values for most variables. Nevertheless, supplementation with chemical fertilization was necessary. Composted sewage sludge with eucalyptus bark, at the standard dosage, can be used for the commercial production of P. dubium seedlings, thus preventing the dangerous disposal of waste and strongly decreasing associated environmental hazards. [ABSTRACT FROM AUTHOR]

One of the issues facing modern society, regardless of the socio-economic level of the communities involved, is the development of sustainable strategies for the management of sludge/biosolids. Nowadays, it is imperative to replace solutions aimed at simply "disposing of" with those oriented toward "maximizing recovery benefits". It is desirable that agricultural use remains the main option in sludge/biosolids management; however, to ensure effective and safe agronomic benefits, correctly fulfill the legal requirements, and build stakeholder and public confidence, rigorous and sustainable procedures need to be established. The development of realistic and enforceable regulations is crucial, as they represent the right balance between the different aspects of coordinated and effective management. Furthermore, it is important to recognize that regulations must be supported by standardized characterization procedures and good practice guidelines because well-defined procedures allow the legal requirements to be correctly and uniformly met, as well as to reliably compare the results obtained under different conditions and their wide application in different regulatory contexts. In this article, the main aspects for (i) the sustainable application of sludge/biosolids in agriculture and (ii) the development of standardized characterization methods and procedures, thus ensuring effective agronomic benefits and guaranteeing quality/safety of agricultural products, are discussed. Some pieces on the evolution of European legislation in this field are also provided. Details and results of the research activities behind the development of these methods/procedures can be found in the referenced documents. [ABSTRACT FROM AUTHOR]

Abstract Sewage sludge (SS) has nutritional contents and has been implemented in the cultivation of seedlings. This study aimed to evaluate the quality of Malpighia emarginata DC. seedlings produced in different substrates with SS. Treatments were implemented with the addition of SS, and after 180 days seedling the characteristics were measured: aerial part and root system length, stem base diameter, number of leaves, fresh and dry mass of aerial part and root, and total biomass. The Dickson Quality Index (DQI) was calculated and the macro and micronutrient content of the aerial part and root. The accumulation of macronutrients in the root system followed the order of N>K>P>Ca>Mg>S, and aerial part of N>Ca>K>P>Mg>S, in the two vegetative structures N and S were in lower concentration. For micronutrients, the accumulation in the root system occurred with Fe>Zn>Mn>Cu>B, and aerial part with Fe>Mn>Zn>B>Cu. It was noted that in the two vegetative structures the Fe content was more concentrated. The use of SS in the substrate formulation proved effective in obtaining viable seedlings for field planting, being recommended the treatment with 60% SS + 40% organic compost.

Agricultural application is the primary method of recycling sewage sludge. It is an alternative for recycling this residue, providing nutrients and organic matter to crops and soil. However, sewage treatment and management issues may impact its quality. The main objective of the research was to determine the quality of sewage sludge generated at the Kumasi Wastewater Treatment Plant (KWTP). Understanding the effects of using sludge on soil and plants is critical. To overcome this constraint, the soil microbial biomass was used to quantify the growth of microorganisms. The levels of potentially toxic elements in the sludge using atomic absorption spectrometry (AAS) are based on US EPA part 503 regulations for the disposal and management of biosolids. This study found that trace metal concentrations in the biosolids were lower than the referenced background standards threshold. Although the microbial biomass, nutrients and bacteria levels were within the accepted values for their possible use as soil fertilizer. The ecological risk index (135.10) indicated that the level of arsenic was high in the sludge. The salinity in the sludge was low, with electrical conductivity (EC) being high (60.80–436.00 μS/cm) and pH decreasing with age (6.73–7.69). The sludge produced at KWTP is of good quality and meets international standards with only a high concentration of As. This can be used for soil amendment when As is reduced in the sludge.

Astudy was conducted in three agroecosystems in California (Sacramento, Solano, and Merced counties) that received biosolids applications for 20 yr. Management varied in application rates and frequencies, resulting in average cumulative amount of biosolids applied of 74 (Solano), 105 (Merced), and 359 (Sacramento) Mg biosolidsdry ha-1 , resulting in the addition of 26 (Solano), 36 (Merced), and 125 (Sacramento) Mg biosolids-C ha-1 . Measurements included soil organic carbon (SOC) and total nitrogen (N) concentrations from 0 to 100 cm and microbial biomass C (MBC) and microbial biomass N (MBN) from 0 to 30 cm in biosolids-amended and control sites. Biosolids treatments had greater amounts of SOC and total N at all sites, and MBC and MBN were greatest at Sacramento and Solano. The largest increases in SOC were at the site that received the lowest cumulative loading rate of biosolids (Solano), where SOC content to 100 cm was 50% greater in amended soils (p

It is generally accepted that some trace organic contaminants (TrOCs) pass through the wastewater treatment process without being properly treated and find their way into waterbodies. These molecules can also be concentrated within the biosolids (BS) through adsorption. The presence of TrOCs in BS, which are then commonly used as soil amendments in agriculture, may affect plant growth and viability. The potential risks posed by TrOCs are usually ignored because they are present in low concentrations and mostly have relatively short half-lives. However, the continuous addition of these substances in water sources and on farmlands makes them pseudo-persistent. To reduce the concentrations of selected TrOCs from these BS, Pseudomonas yamanorum LBUM636 (PY) was tested with and without a commercial bacterial blend of Bacillus spp. (BC). About 60% removal of atrazine was achieved using PY-amended BS. Bioslurries inoculated with PY had relatively high laccase activity at about 2,200 U/L. Laccase activity was seven times higher in samples where BC was also present, which suggests a synergistic effect between BC and PY. Concentrations of phenazine-1-carboxylic acid, an antibiotic with a biopesticide effect, were also relatively important in PY-inoculated bioslurries. HIGHLIGHTS Pseudomonas yamanorum was successfully grown on municipal biosolids (BS) with/without the addition of a commercial blend of Bacillus spp.; P. yamanorum induced the reduction of atrazine from BS.; Phenazine-1-carboxylic acid was produced in P. yamanorum inoculated BS.;

Sewage sludge in natura is rich in nutrients, water, and organic matter and is essential for plant development. However, sewage sludge is diluted with water when composted, which could hamper plant growth. Therefore, supplementation with chemical fertilization may be necessary. This study evaluated the performance of composted sewage sludge (CSS) in producing Peltophorum dubium (Spreng.) Taub. seedlings with and without chemical fertilization via fertigation. The experiment was completely randomized in a 3 × 4 factorial scheme, with four fertigation (Ca(NO3)2(H2O)x: 0.87; (NH4)(H2PO4): 0.21; KCl: 0.47; (NH4)2SO4: 0.11; CH₄N₂O: 0.54; MgSO4: 0.52; Fe (13%): 0.03; B(OH)3: 6.00; CuSO4: 0.60; ZnSO4: 1.40; MnSO4: 6.00; Na2MoO4: 0.16 g L−1) doses: zero, standard, duplicate, and quadruplicate. In addition, three substrates were used: commercial substrate as the control, sewage sludge composted with sugarcane bagasse (LBC), and sewage sludge composted with Eucalyptus bark (LCE). The development of the seedlings was measured through the following variables: height, stem diameter, shoot/root ratio, leaf dry mass, root dry mass, total dry mass, green color index, the Dickson Quality Index, and the accumulation of nutrients in plant tissue. The seedlings produced with LCE that were subjected to the standard dose (1×) and the quadruplicate dose (4×) had the statistically highest mean values for most variables. Nevertheless, supplementation with chemical fertilization was necessary. Composted sewage sludge with eucalyptus bark, at the standard dosage, can be used for the commercial production of P. dubium seedlings, thus preventing the dangerous disposal of waste and strongly decreasing associated environmental hazards.

Background: Over 40% of the six million dry metric tons of sewage sludge, often referred to as biosolids, produced annually in the United States is land applied. Biosolids serve as a sink for emerging pollutants which can be toxic and persist in the environment, yet their fate after land application and their impacts on human health have not been well studied. These gaps in our understanding are exacerbated by the absence of systematic monitoring programs and defined standards for human health protection. Methods: The purpose of this paper is to call critical attention to the knowledge gaps that currently exist regarding emerging pollutants in biosolids and to underscore the need for evidence-based testing standards and regulatory frameworks for human health protection when biosolids are land applied. A scoping review methodology was used to identify research conducted within the last decade, current regulatory standards, and government publications regarding emerging pollutants in land applied biosolids. Results: Current research indicates that persistent organic compounds, or emerging pollutants, found in pharmaceuticals and personal care products, microplastics, and per- and polyfluoroalkyl substances (PFAS) have the potential to contaminate ground and surface water, and the uptake of these substances from soil amended by the land application of biosolids can result in contamination of food sources. Advanced technologies to remove these contaminants from wastewater treatment plant influent, effluent, and biosolids destined for land application along with tools to detect and quantify emerging pollutants are critical for human health protection. Conclusions: To address these current risks, there needs to be a significant investment in ongoing research and infrastructure support for advancements in wastewater treatment; expanded manufacture and use of sustainable products; increased public communication of the risks associated with overuse of pharmaceuticals and plastics; and development and implementation of regulations that are protective of health and the environment. [ABSTRACT FROM AUTHOR]

Class A biosolids is a treated sewage sludge, commonly applied to agricultural fields, home lawns/gardens, golf courses, forests, and remediation sites around the world. This practice is of public and agricultural concern due to the possibility that biosolids contain antibiotic-resistant bacteria and fungal pathogens that could persist for extended periods in soil. This possibility was determined by metatranscriptomic analysis of virulence, antibiotic resistance, and plasmid conjugation genes, a Class A biosolids, organically managed soil, and biosolids-amended soil under realistic conditions. Biosolids harbored numerous transcriptionally active pathogens, antibiotic resistance genes, and conjugative genes that annotated mostly to Gram-positive pathogens of animal hosts. Biosolids amendment to soil significantly increased the expression of virulence genes by numerous pathogens and antibiotic-resistant genes that were strongly associated with biosolids. Biosolids amendment also significantly increased the expression of virulence genes by native soil fungal pathogens of plant hosts, which suggests higher risks of crop damage by soil fungal pathogens in biosolids-amended soil. Although results are likely to be different in other soils, biosolids, and microbial growth conditions, they provide a more holistic, accurate view of potential health risks associated with biosolids and biosolids-amended soils than has been achievable with more selective cultivation and PCR-based techniques. [ABSTRACT FROM AUTHOR]

The use of sludge in agriculture can contribute to reducing environmental pollution due to the disposal of waste sludge from wastewater treatment plants, thus avoiding incineration or other polluting and costly processes. Biosolids for agriculture are obtained from raw sewage sludge by digestion and stabilisation processes. These processes ensure the reduction of toxic chemicals and pathogen concentrations in sludge so that its use in agriculture does not harm soil, plants, groundwater and not least the health of consumers of agricultural plant and animal products. Biosolids can be used as a source of organic matter for some organic or organo-mineral fertilizers. In order to obtain a valuable organo-mineral fertilizer in terms of nutrient composition, it is necessary to enrich the biosolid by adding minerals/ingredients to the recipe. The characteristics of the resulting fertilizers must meet the requirements of the organo-mineral fertilizer category. The paper presents research on the influence of mineral fertilizer additions on some physico-chemical properties of granular biosolid fertilizers, such as: grain moisture, grain size fraction, compressive strength and bulk density. [ABSTRACT FROM AUTHOR]

The recent discovery of microplastic occurrence in most ecosystems is raising health concerns globally, yet the fate of microplastics is poorly known, particularly in the terrestrial environment. Here, we review the effect of land applications of biosolids on microplastic contamination in agricultural soils. We focus on separation and identification methods, distribution in wastewater, and retention, migration and degradation in soils. We also discuss the uptake of microplastics by microorganisms. The number of microplastic particles in biosolids ranges from 506 to 15,385 per kg of biosolids. After biosolid application on land, microplastic number ranges from 18 to 6.9 × 105 particles per kg of soil, depending on the soil composition. Microplastic retention in soils increases with soil organic carbon concentration, Fe and Al oxide concentrations, and soil ionic strength. Biodegradation of microplastics causes mass loss, changes in chemical composition, reduction in molecular weight and mechanical strength, and gas production of carbon dioxide and methane. [ABSTRACT FROM AUTHOR]

This review examines the economic impact of Latin American regulations, strategies, and community involvement in mitigating the detrimental effects of mismanaged municipal domestic wastewater on public health, safety, and the economy. A systematic review and meta-analysis are conducted to assess the economic potential of reclaimed water in the region, utilizing various data sources and methodologies. The findings reveal that Latin America faces challenges in wastewater treatment, regulation, and resource management, affecting the market potential of reclaimed water. However, resource recovery initiatives present economic opportunities, including cost reduction, agricultural growth, energy recovery, and resource reuse. The study also highlights the lack of sanitation and wastewater treatment coverage data in many Latin American countries. By examining the commercial possibilities, regulatory frameworks, and environmental benefits of reclaimed water, this research provides valuable insights for sustainable water management and resource recovery policymakers, practitioners, and researchers. Furthermore, it emphasizes the economic advantages of utilizing reclaimed water and biosolids in Latin America, advocating for the implementation of strong regulations and policies to promote job creation and economic growth. [ABSTRACT FROM AUTHOR]

Purpose: The response of sweet sorghum to biosolids application under different irrigation regimes was studied in a field experiment conducted during 2010 and 2011 in Central Greece. The study assessed the effects of soil application of biosolids on plant height, biomass production, and water use efficiency. Method: The experiment consisted of nine treatments with three replications, including the application of biosolids to the soil, the application of fertilizer, and an untreated control, with three levels of irrigation (100%, 80%, and 60% of the crop water needs). Results: The study found that plant height was similar regardless of whether biosolids or fertilizer was applied. Under reduced irrigation, the application of biosolids at a rate of 5 Mg/ha resulted in a 9.2-11.5% increase in dry biomass production of sweet sorghum compared to dry biomass production from inorganic fertilizer application. When biosolids were applied with reduced irrigation, the dry biomass yield was similar to that produced by inorganic fertilizer application under full irrigation. Additionally, this was achieved while using 31.4% less irrigation water. Biosolids application to soil improved water use efficiency by up to 34% compared to fertilizer application. Conclusion: The findings of this research suggest that substituting inorganic fertilizers with biosolids application can lead to significant water savings. [ABSTRACT FROM AUTHOR]

IntroductionThe use of biosolids from wastewater treatment plants in agriculture is considered relevant for the promotion of sustainable agricultural practices, the improvement of soil fertility, and the reduction of dependence on synthetic chemical products. The Dominican Republic is today the world's largest producer of organic bananas and the main exporter of organic and fair-trade bananas to Europe. The biosolids generated in the wastewater treatment plants in the Dominican Republic currently have no use. In other countries, biosolids are used for agriculture, although biosolids have different characteristics in each place and their potential must be analyzed. In the Dominican Republic, there is no research that analyzes biosolids and their impact on agriculture. This research aims to compare the nutritional composition of bananas in plantations fertilized with different doses of biosolids and other organic fertilizers.MethodsFor this test, five blocks were prepared with organic fertilization, another with potassium sulfate, and a control block. Laboratory analysis was used to determine the characteristics of the biosolids used and also to know the nutritional composition of bananas of the Williams variety.ResultsThe results, when compared, show the impact that each of these fertilizers has or can have on the production of organic bananas in the Dominican Republic.DiscussionThe use of dose Y of the biosolid, characterized by the application of 16 kilograms of biosolid per plant, is the most recommended to fertilize the banana since the collected fruits presented the most optimal nutritional values.

Purpose Due to the urgent need for sustainable agro-industrial waste management, a field experiment was conducted to evaluate the application of biosolids as organic fertilizer in a corn cultivation crop. In addition, to achieve food security, the study aimed to assess metals concentrations in soil and maize plants and enrichment factors (EF) for soils and plants.Method Four sites with a biosolids application were studied and compared against a control. Physicochemical properties of soils and heavy metal contents were evaluated after one year of application of biosolids. Metal concentrations, average kernel yield and biomass were measured in corn plants.Results The results demonstrated that the biosolids increased the content of organic matter, nitrogen, phosphorus, and exchangeable bases in the soil. In addition, the concentration of heavy metals in soils with biosolids was higher than in soils without treatment, and the concentration of heavy metals in the corn kernels did not exceed the maximum recommended limits. However, EF values showed a considerable contamination grade due to the accumulation of metals.Conclusion Some of the physical and chemical characteristics of soil were improved by incorporating biosolids, but the metal content in the soil increased. Also, the application of biosolids increased the plant height and corn yield. Therefore, biosolids can be used as organic fertilizer sources; however, it is necessary to carry out periodic evaluations to ensure low levels of enrichment in crops and soil, thus guaranteeing the safety of biosolids as soil fertilizers.

Co-pyrolysis technology is an effective method to reduce heavy metal concentration in biochar produced from biosolids. In the current study, the effect of co-pyrolysis feedstock on product yield and properties was studied by mixing Biosolids (BS) with Wheat Straw (WS) and Canola Straw (CS) in a 3:1 mass ratio and carrying out thermal decomposition at 700 °C in a fluid bed reactor. This study found that the feedstock ash content and the volatile matter had a significant effect on biochar, oil, and gas yields from co-pyrolysis. The results also indicated that the addition of WS and CS feedstock notably reduced As, Cd, Cr, Cu, Ni, Pb, Se, and Zn concentrations in the biochar, due to the net effect of dilution and synergistic effects. BS-WS and BS-CS co-pyrolysis reduced Cu concentration in biochar by 61.6% and 63.3%, respectively, and Zn concentration by 66.4% and 64.4%, respectively. Lignocellulosic biomass addition also reduced biochar yield and improved C, H, and N content, along with the calorific value and the thermal stability of biochar. C content was increased by 36.9% in BS: WS biochar and 43.3% in BS: CS biochar compared to solely biosolids' biochar. The calorific value of biochar was increased by 43.5% and 52.9% in BS-WS biochar and BS-CS biochar compared to biosolids' biochar. During co-pyrolysis, CS addition produced oil with the lowest mole percentage of nitrogenated compounds. However, the addition of WS and CS increased co-pyrolysis oil acidity. Biosolids co-pyrolysis with WS and CS also increased the gas yield and the heating value compared to biosolids pyrolysis. Furthermore, the synergistic effect between biosolids and co-feedstocks resulted in increased gas yields and decreased oil and biochar yields. [ABSTRACT FROM AUTHOR]

The occurrence of antibiotic-resistant bacteria (ARB) in wastewater treatment plants (WWTPs) has become an occupational and environmental concern. WWTPs are engineered systems that treat wastewater to meet public health standards before release into the environment. The residuals, as either effluent or solids, are then discharged or beneficially recycled into the environment. Since these wastes contain a diverse array of microorganisms, some of which are resistant to commonly used antibiotics, there is a potential for these organisms to spread in the environment via residual recycling and effluent discharge. Human infections with ARB are increasing, and it is not well known how the interaction between humans and the environment plays a role in this process. WWTP workers, who are on the front lines, may come into direct contact with materials containing these microbes. This study aimed to determine the number of ARB present in both air and sewage sludges in a WWTP using nonselective media supplemented with two antibiotics (ciprofloxacin and azithromycin). The densities of total heterotrophic bacteria, ciprofloxacin-resistant bacteria, and azithromycin-resistant bacteria were 7.82 × 105 − 4.7 × 109, 7.87 × 103 − 1.05 × 108, and 2.27 × 105 − 1.16 × 109 CFU/g, respectively. The prevalence [(concentration on medium with antibiotics/concentration on medium without antibiotics) × 100] of ciprofloxacin-resistant bacteria in treated sludge was twice as low as in digested sludge and approximately three times lower than in raw sludge. For azithromycin, the prevalence of resistant bacteria in treated sludge was about the same in digested and nearly twice lower than in raw sludge. Despite a marked reduction in the mean prevalence of resistant bacteria in dewatered treated sludge for both antibiotics, these differences were not significant. The highest prevalence of antibiotic resistance was observed for azithromycin. Similarly, the prevalence of airborne azithromycin-resistant bacteria inside the belt filter press room (BFPR) was nearly seven times higher than the prevalence of airborne ciprofloxacin-resistant bacteria. These concentrations of ARB were not negligible and may represent an exposure pathway for some workers in WWTPs. [ABSTRACT FROM AUTHOR]

Pyrolysis is the process whereby carbonaceous materials, such as biosolids, are heated between 400°C and 900°C in the absence of oxygen. Three main products are generated: a solid product called biochar, a py-liquid that consists of aqueous phase and non-aqueous phase liquid, and py-gas. The biochar holds value as a beneficial soil amendment and sequesters carbon. The py-liquid is potentially hazardous and needs to be dealt with (including potentially reducing it on-site via catalysis or thermal oxidation). Py-gas can be used on-site for energy recovery. Pyrolysis has gained recent interest due to concern over perand polyfluoroalkyl substances (PFAS) in biosolids. Although pyrolysis can remove PFAS from biosolids, it has been shown to produce PFAS that reside in py-liquid, and the fate in py-gas remains a knowledge gap. More research is needed to help close the PFAS and fluorine mass balance through pyrolysis influent and effluent products because pyrolysis alone does not destroy all PFAS. The moisture content of biosolids substantially affects the energy balance for pyrolysis. Utilities that already produce a dried biosolids product are in a better position to install pyrolysis. Pyrolysis has both defined benefits (solids reduction, PFAS removal from biosolids, and biochar production) as well as remaining questions (the fate of PFAS in py-gas and py-liquid, mass balance on nutrients, and py-liquid handling options) that will be answered through more pilot and full-scale demonstrations. Regulations and local policies (such as carbon sequestration credits) could affect pyrolysis implementation. Pyrolysis should be considered as an option in the biosolids stabilization toolbox with application being based on individual circumstances of a utility (e.g., energy, moisture content of biosolids, PFAS). Practitioner Points • Pyrolysis has known benefits but limited full-scale operational data. • Pyrolysis removes PFAS from biochar, but PFAS fate in gas phase is unknown. • Moisture content of influent feed solids affects energy balance of pyrolysis.• Policy on PFAS, carbon sequestration, or renewable energy could impact pyrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The three processes achieved hygienization of sludge, maintained after 72 h storage. • Salmonella was cultured only in PS and MAD; qPCR had negative results in all samples. • TP increased removal of total and viable E.coli in TAD but favored VBNC state. • PMA technique cannot fully discriminate viable from not viable bacteria in sludge. Sewage sludge should be stabilized for its beneficial use and pathogens, among other factors, should comply with environmental regulations. Three sludge stabilization process were compared to assess their suitability for producing Class A biosolids: MAD-AT (mesophilic (37 °C) anaerobic digestion (MAD) followed by an alkaline treatment (AT)); TAD (thermophilic (55 °C) anaerobic digester); and TP-TAD (mild thermal (80 °C, 1 h) pretreatment (TP) followed by a TAD). E. coli and Salmonella spp. were determined, differentiating three possible states: total cells (qPCR), viable cells using the propidium monoazide method (PMA-qPCR), and culturable cells (MPN). Culture techniques followed by the confirmative biochemical tests identified the presence of Salmonella spp. in PS and MAD samples, while the molecular methods (qPCR and PMA-qPCR) showed negative results in all samples. The TP + TAD arrangement reduced the concentration of total and viable E. coli cells in a greater extent than the TAD process. However, an increase of culturable E. coli was observed in the corresponding TAD step, indicating that the mild thermal pretreatment induced the viable but non-culturable state in E. coli. In addition, the PMA technique did not discriminate viable from non-viable bacteria in complex matrices. The three processes produced Class A biosolids (fecal coliforms < 1000 MPN/gTS and Salmonella spp, < 3 MPN/gTS) maintaining compliance after a 72 h storage period. It appears that the TP step favors the viable but not culturable state in E. coli cells, a finding that should be considered when adopting mild thermal treatment in sludge stabilization process arrangements. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to verify the effectiveness of composting in the sanitization of sludge from urban sewage (SS). The treatments (T) used consisted of SS mixed with sugarcane bagasse (SB), tree pruning residues (TP), poultry litter (PL) or grass clipping (GC) at a carbon/nitrogen ratio of approximately 30/1 and ratios of T1 (SS+SB), T2 (SS+SB+TP), T3 (SS+SB+GC), T4 (SS+SB+PL) or T5 (SS+SB+TP+GC). Temperature was measured daily for over 280 days of composting. Every two weeks, the compounds were analyzed for thermotolerant coliforms and viable helminth eggs using the multiple-tube and Yanko techniques; and once each month to identify Cryptosporidium spp. and Giardia spp. (oo)cysts using the sucrose and zinc sulfate centrifugal flotation technique and nested PCR followed by sequencing. The maximum temperatures measured in the thermophilic phase of the compounds ranged from 55°C to 64.8°C, and at day 280, weight reductions of 27% (T1), 48% (T2), 63% (T3), 66% (T4) and 64% (T5) were observed. The absence of fecal coliforms was observed from day 98 (T4), day 126 (T1), day 196 (T3 and T5) and day 210 (T2). All treatments resulted in helminth egg inviability and the absence of protozoan (oo)cysts. Only T4 and T5 were positive for G. duodenalis according to the sequencing analysis. In conclusion, high temperatures during the composting thermophilic phase made the use of pathogens required by legislation unfeasible; therefore, it is important to investigate the viability of protozoa in compounds to ensure a safe final product for human and animal health. [ABSTRACT FROM AUTHOR]

The study refers to the assessment of the effectiveness of treatments of topsoil of fly ash from a fresh deposit. Bioavailability reduction of metals: chromium, copper and lead from soil to the plant tissue, for a healthy vegetation cover of a leguminous plant species is aimed. The modification of metal mobility in the top layer of fly ash through the use of biosolids (municipal sludge) as organic fertilizers alone or mixed with pillared indigenous tuff is indicated by a bioavailability index of metal accumulation in plant tissue. This indicator of bioavailability of heavy metals is called transfer factor (TF) and is the ratio of metal content in plant tissue QP mg/kg DM of total metal content in fly ash treated or untreated site QS mg/kg DM TF = QP/QS. Transfer factor from soil to plant tissue for chromium and copper decreases from 0.11 – 0.18 to 0.06 – 0.08 and from 0.28 to 0.03 for lead when treating the top layer of fly ash with biosolids mixed with pillared indigenous tuff.

The storage of waste dump gravely deteriorates the soil’s physical, chemical and biological properties, both in the storage area and the surrounding zones. In time, serious perturbations may occur in the biocenosis from the surrounding ecosystems, through the sweeping away of the inorganic matter or through precipitations. The main problem in this case is to find the most suitable phytoremediation method for these waste dumps, by sowing plant species (grasses), in order to stop the erosion generated by wind and rain. Establishing a herbaceous “carpet” , in time, is very difficult, because the waste dump contains no organic matter, has a weak water retaining capacity and has a high bareness index. The purpose of this study was the experimentation of a method of cultivating the waste dumps using alfalfa, fescue and biosolids as fertilizers.