Publications by authors named "Savia Gavazza"

The contamination of soil and groundwater by amino-, nitro-, and chloroaromatics, which are compounds extensively used in chemical manufacturing, including pesticide production, poses significant risks due to their toxicity and mutagenicity. This study presents a proof-of-concept blended bacterial culture, developed by combining individual contaminant-degrading enrichments. The culture was tested for bioremediation of three contaminated environmental matrices from a former agrochemical site in northeastern Brazil: groundwater (total contaminant concentration: 100-1000 μM), soil (287-596 mg/kg), and highly contaminated water from overflow containment boxes (940-3153 μM).

View Article and Find Full Text PDF

The potential for bioremediation of dichloroanilines (2,3- and 3,4-DCA) and dichloronitrobenzenes (3,4-, 2,5-, and 2,3-DCNB) was investigated using inocula from an industrial site in the northeast of Brazil. Anaerobic biotransformation of these chlorinated compounds was observed in microcosms simulating site conditions, particularly when an electron donor was added. To disentangle specific transformation reactions, subcultures from active anaerobic microcosms were enriched with individual DCA or DCNB isomers.

View Article and Find Full Text PDF

The removal of the tetra-azo dye Direct Black 22 (DB22) using the microalga was evaluated in the present study, aiming to understand the contribution of different processes (biodegradation, photodegradation, and adsorption) in the removal of this contaminant. The growth and morphological characteristics of were not affected by the presence of the dye in the reaction medium. The efficiency of dye removal was 62.

View Article and Find Full Text PDF

Groundwater and soil contamination by aromatic amines (AAs), used in the production of polymers, plastics, and pesticides, often results from improper waste disposal and accidental leaks. These compounds are resistant to anaerobic degradation; however, micro-aeration can enhance this process by promoting microbial interactions. In batch assays, anaerobic degradation of aniline (0.

View Article and Find Full Text PDF

Linear alkylbenzene sulfonate (LAS) is a synthetic anionic surfactant that is found in certain amounts in wastewaters and even in water bodies, despite its known biodegradability. This study aimed to assess the influence of nitrate, sulphate, and iron (III) on LAS anaerobic degradation and biomass microbial diversity. Batch reactors were inoculated with anaerobic biomass, nutrients, LAS (20 mg L), one of the three electron acceptors, and ethanol (40 mg L) as a co-substrate.

View Article and Find Full Text PDF
Article Synopsis
  • Compound specific isotope analysis (CSIA) is effective for tracking the degradation of contaminants in groundwater, but lacks methods for low concentration samples, particularly for H- and N-CSIA, which have higher detection limits compared to C-CSIA.
  • The study successfully uses polar organic chemical integrative samplers (POCIS) with C-, H-, and N-CSIA to analyze nitro- and amino-substituted chlorobenzenes, achieving isotopic equilibrium in lab tests after 30 days and showing comparable method quantification limits to solid phase extraction.
  • Field tests in a constructed wetland revealed that POCIS-CSIA maintained isotope accuracy (<1 ‰ difference for C and N) after 60 days, with microbial
View Article and Find Full Text PDF

This study investigated the performance of a granular filtration system (GFS) composed of a rock filter (RF), a rapid sand filter (RSF), and an activated carbon filter (ACF), applied to the post-treatment of an anaerobic reactor effluent. Four filtration rates (FR) were applied to the GFS (in m·m·d): 100-60-60, 100-90-90, 200-120-120, and 200-160-160, for RF-RSF-ACF, respectively. A clarified final effluent with low turbidity (~ 10 NTU), solids (~ 6.

View Article and Find Full Text PDF

The textile industry is known for its large consumption of water, energy, and chemical products, making it one of the most environmentally impactful activities. To measure these environmental impacts, life cycle analysis (LCA) is a powerful tool that considers the entire process, from the extraction of raw materials to the finalization of textile products. In this context, this work aimed to present a systematic study on the use of the LCA methodology in the environmental assessment of effluents from the textile industry.

View Article and Find Full Text PDF

The effect on the morpho-physiological parameters and yield of sorghum cultivated in a greenhouse with reclaimed water (RW) and (dehydrated sludge (DS) obtained in a sewage treatment plant, was evaluated. Six treatments (T), with five repetitions each, were carried out in entirely randomized blocks. Water (W) was used in T1 (W) (control), T2 (W + NPK), and T3 (W + DS); RW was used in T4 (RW), T5 (RW + P), and T6 (RW + DS).

View Article and Find Full Text PDF

The effect of six important factors on the anaerobic biodegradation of linear alkylbenzene sulphonate (LAS) was evaluated using a response surface methodology. The factors were: (i) co-substrate concentration (CC), (ii) contact time between LAS and microorganisms, (iii) temperature, (iv) hardness, (v) pH, and (vi) LAS source. The results showed that individually or combined, CC with chemical oxygen demand (COD) ≤50 mg L was the factor that mostly favoured LAS biodegradation; whereas at COD >50 mg L, adsorption to sludge and solubilisation in the aqueous medium were favoured.

View Article and Find Full Text PDF

Simultaneous removal of organic matter, nitrogen, and phosphorus, via simultaneous nitrification and denitrification (SND) and enhanced biological phosphorus removal processes, was evaluated in a pilot-scale sequential batch reactor. The focus was on granule's morphology, stability, microbiological composition, and reactor performance while treating diluted domestic wastewater with total chemical oxygen demand (COD) of ≈ 200 mg.L.

View Article and Find Full Text PDF

Real textile wastewater containing high salinity (up to 12.6 g·kg) and surfactant (up to 5.9 mg·L of linear alkylbenzene sulfonate - LAS) was submitted to biological treatment for colour (up to 652 mg Pt-Co·L) and sulphate (up to 1,568.

View Article and Find Full Text PDF

In this study, start-up strategies to develop conventional aerobic granular sludge (AGS) and algal aerobic granular sludge (AAGS) (photogranules), were investigated. The granulation experiment was conducted in four sequencing batch reactors (SBR), of which two were conventional SBRs (RC1, RC2) used as control, and two were photo-SBRs (R1, R2). R1 and RC1 were operated with a 40-min feeding during the reactors´ anaerobic cycle period, whereas R2 and RC2 with a 60-min feeding.

View Article and Find Full Text PDF

As military applications of the insensitive munitions compounds (IMCs) 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO) increase, there is a growing need to understand their environmental fate and to develop remediation strategies to mitigate their impacts. Iron (II) monosulfide (FeS) minerals are abundant in freshwater and marine sediments, marshes, and hydrothermal environments. This study shows that FeS solids can reduce DNAN and NTO to their corresponding amines under anoxic ambient conditions.

View Article and Find Full Text PDF

2,4-Dinitroanisole (DNAN) is a toxic compound increasingly used by the military that can be released into the environment on the soil of training fields and in the wastewater of manufacturing plants. DNAN's nitro groups are anaerobically reduced to amino groups by microorganisms when electron donors are available. Using anaerobic sludge as the inoculum, we tested different electron donors for DNAN bioreduction at 20 and 30 °C: acetate, ethanol, pyruvate, hydrogen, and hydrogen + pyruvate.

View Article and Find Full Text PDF

Sensitive biomes, such as coastal ecosystems, have become increasingly susceptible to environmental impacts caused by oil logistics and storing, which, although more efficient nowadays, still cause spills. Thus, bioremediation techniques attract attention owing to their low impact on the environment. Among petroleum-based compounds, polycyclic aromatic hydrocarbons (PAHs) are known for their potential impact and persistence in the environment.

View Article and Find Full Text PDF

2,4-Dinitroanisole (DNAN) is an insensitive munitions compound expected to replace 2,4,6-trinitrotoluene (TNT). The product of DNAN's reduction in the environment is 2,4-diaminoanisole (DAAN), a toxic and carcinogenic aromatic amine. DAAN is known to become irreversibly incorporated into soil natural organic matter (NOM) after DNAN's reduction.

View Article and Find Full Text PDF

The nitroheterocyclic 3-nitro-1,2,4-triazol-5-one (NTO) is an ingredient of insensitive explosives increasingly used by the military, becoming an emergent environmental pollutant. Cometabolic biotransformation of NTO occurs in mixed microbial cultures in soils and sludges with excess electron-donating substrates. Herein, we present the unusual energy-yielding metabolic process of NTO respiration, in which the NTO reduction to 3-amino-1,2,4-triazol-5-one (ATO) is linked to the anoxic acetate oxidation to CO by a culture enriched from municipal anaerobic digester sludge.

View Article and Find Full Text PDF

Insensitive munitions compounds, such as 2,4-dinitroanisole (DNAN), are replacing conventional explosives. DNAN is anaerobically reduced to 2,4-diaminoanisole (DAAN), a toxic aromatic amine. However, the removal of DAAN under different redox conditions is yet to be elucidated.

View Article and Find Full Text PDF

We evaluate the behavior of a device designed to automatically divert and store the first flush of harvested rainwater in cisterns. The first phase (PI) was conducted with artificial precipitation in an experimental installation seeking to identify how many millimeters of rainwater should be diverted to preserve the rainwater quality. In the second phase (PII), we designed a PVC-pipe device to store the first millimeter of rainwater, and tested it in field (a rural area in Brazil) during two real rainfall events.

View Article and Find Full Text PDF

Manipueira is a carbohydrate-rich agro-industrial waste from cassava processing. It is considered well suitable for biotechnological processes, such as hydrogen and carboxylic acids production, due to the high content of easily degradable organic matter. However, the proper methanogenesis inhibition method, inoculum type, and organic loads are factors still limiting the processes.

View Article and Find Full Text PDF

The decision-making process involved in municipal solid waste management (MSWM) must consider more than just financial aspects, which makes it a difficult task in developing countries. The Recife Metropolitan Region (RMR) in the Northeast of Brazil faces a MSWM problem that has been ongoing since the 1970s, with no common solution. In order to direct short-term solutions, three MSWM alternatives were outlined for the RMR, considering the current and future situations, the time and cost involved and social/environmental criteria.

View Article and Find Full Text PDF

The aim of this study has been to produce 1,3-propanediol (1,3-PDO) from glycerol (gly) fermentation by means of a microbial mixed culture (granular sludge), as well as to establish the operational conditions of two up-flow anaerobic sludge blanket (UASB) reactors in order to achieve a maximum 1,3-PDO yield. The UASB reactors with initial pH values set at 6.8 and 5.

View Article and Find Full Text PDF

The aim of the present study was to assess the bioremediation of estuarine sediments contaminated with diesel oil. The following two experiments were performed: natural attenuation (NA) and stimulated natural attenuation (SNA), using rhamnolipid as biosurfactant. Sediment samples were accommodated into glass columns and then contaminated with diesel oil on the top.

View Article and Find Full Text PDF