Sedimentary environmental quality of a biosphere reserve estuary in southwestern Iberian Peninsula

The Huelva estuary is formed by the common mouths of the Odiel and Tinto Rivers, and inside this ecosystem is the biosphere reserve of the Odiel saltmarshes. This ecosystem has been historically affected by acid mine drainage (AMD) and by releases of pollutants from five phosphoric acid industrial plants and phosphogypsum (PG) waste stacks located in the area. This study carried out a comprehensive assessment of the environmental impact of the biosphere reserve of the Odiel saltmarshes. To this end, it was necessary to find a suitable sedimentary background (Piedras River in our case). To quantify this impact, several pollution indexes were used. According to the values reached by the indexes, this impact was classified as "serious" pollution for most trace elements, excepting the deepest layers, and "low-moderate" pollution for the 238U-series radionuclides, while no pollution for the 232Th-series and 40K radionuclides was found as expected.

A review on the environmental impact of phosphogypsum and potential health impacts through the release of nanoparticles

Many industrial by-products have been disposed along coastlines, generating profound marine changes. Phosphogypsum (PG) is a solid by-product generated in the production of phosphoric acid (PA) using conventional synthesis methods. The raw material, about 50 times more radioactive as compared to unperturbed soils, is dissolved in diluted sulfuric acid (70%) forming PG and PA. The majority of both, reactive hazardous elements and natural radionuclides, remain bound to the PG. A nonnegligible fraction of PG occurs as nanoparticles (<0.1 μm). When PG are used for e.g., agriculture or construction purposes, nanoparticles (NPs) can be re-suspended by Aeolian and fluvial processes. Here we provide an overview and evaluation of the geochemical and radiological hazardous risks associated with the different uses of PG. In this review, we show that NPs are important residues in both raw and waste materials originating from the uses of phosphate rock. Different industrial processes in the phosphate fertilizer industries are discussed in the context of the chemical and mineralogical composition as well as size and reactivity of the released NP. We also review how incidental NPs of PG impact the global environment, especially with respect to the distribution of rare earth elements (REEs), toxic elements such as As, Se, and Pb, and natural radionuclides. We also propose the application of advanced techniques and methods to better understand formation and transport of NPs containing elements of high scientific, economic, and environmental importance.

Characterization of multi-metal-resistant Serratia sp. GP01 for treatment of effluent from fertilizer industries

The effluent generated from fertilizer plants in Paradeep in the coast of the Bay of Bengal is the major pollutant causing health hazard in the vicinity of the area with respect to plants, animals and microbes. Samples of effluent were found to contain heavy metals (mg L^-1): Cr (100), Ni (36.975), Mn (68.673), Pb (20.133), Cu (74.44), Zn (176.716), Hg (5.358) and As (24.287) as analyzed by XRF. Indigenous bacterial strains were screened for chromate and multi-metal resistance to remediate the toxic pollutants. The isolated strain G1 was identified as Serratia sp. through 16S-rDNA sequence homology. The potent strain Serratia sp. GP01 treated with 100 mg L^-1 of K₂Cr₂O₇ has shown the efficacy of reducing 69.05 mg L^-1 of Cr over 48 h of incubation. Further, presence of chromate reductase gene (ChR) in Serratia sp. confirmed the enzymatic reduction of Cr(VI). SEM-EDX and SEM mapping analysis revealed substantial biosorption of Cr and other heavy metals present in effluent by Serratia sp. GP01. Antioxidant enzymes such as catalase (72.15 U mL^-1), SOD (57.14 U mL^-1) and peroxidase (62.49 U mL^-1) were found to be higher as compared to the control condition. FTIR study also revealed the role of N-H, O-H, C = C, C-H, C-O, C-N, and C = O functional groups of the cell surface of Serratia sp. treated with K₂Cr₂O₇ and effluent from the fertilizer industry. Isolated strain Serratia sp. could be used for the detoxification of Cr(VI) and other heavy metals in fertilizer plant effluent.

Influence of COVID-19 pandemic on fertilizer companies: The role of competitive advantages

The global crisis caused by COVID-19 pandemic exerted significant impact upon most industries, however, the fertilizer industry has shown some resilience in the supply chain during the crisis. The main research question of the paper concerns the major factors ensuring the resilience of fertilizer companies under such circumstances. The paper presents current situation on the mineral fertilizers market, the influence of COVID-19 pandemic on fertilizer companies, and identifies the main market and industry trends. Then, it offers analytical framework for revealing key factors of success (potential competitive advantages) in the fertilizer industry as well as discusses their role in ensuring resilience of the companies during the crisis. The paper suggests categorization of competitive advantages that helps to identify the sustainable ones. It also reveals special role played by competitive advantages, based on core competencies, and justifies why they need to be developed in this new situation caused by the pandemic. One of the main findings in the paper is the conclusion about «global immunity» of fertilizer companies to environmental turbulence, as well as the conclusion about the new role and the need to transform traditional competitive advantages for the further successful growth of fertilizer companies.

Removal of fluoride from fertilizer industry effluent using carbon nanotubes stabilized in chitosan sponge

Adsorption of fluoride from fertilizer industry effluent using carbon nanotubes stabilized in chitosan sponge as adsorbent was evaluated. The effluent was produced in the washing of acid gases during the reaction in fertilizer production and all assays were performed using this hazardous material. Adsorbent characterization and ions interactions were elucidated from differential scanning calorimetry, thermal gravimetric analyses, X-ray diffraction, scanning electron microscopy dispersive energy X-ray spectroscopy, atomic force microscopy and X-ray photoelectron spectroscopy. The effluent presented pH 3 and its value not changed in the adsorption assays, maintaining the conditions of the process. The kinetics assays of fluoride from industry effluent were performed in different stirring rates from 100 to 300 rpm. It was observed that adsorption was initially fast reaching the equilibrium at 300 rpm in 20 min. The adsorption capacity was around 975.4 mg g^-1, showing the potential of the hybrid material to remove fluoride from a real matrix. The high adsorption capacity was attributed to the chitosan functional groups and the high interaction area promoted by sponge form and the carbon nanotube. Reuse and regeneration of the CNT-CS were investigated and 5 cycles were obtained. The adsorption capacity kept similar values in all cycles.

Bio-based fertilizers: A practical approach towards circular economy

Although for the past 100 years, fertilizer technologies have increasingly used renewable resources, the majority of manufactured products are still based on mineral deposits and fossil fuels. The European Commission has set a goal of 30% reduction of non-renewable resources in fertilizer production. This can only be accomplished if there are incentives for wastes valorization and fines for making use of non-renewable raw materials. This will enable the reduction of eutrophication of surface waters due to the presence of nitrogen and phosphorus, originating from agricultural fields fertilizers. The use of biological waste is a practical solution to recover valuable fertilizer components. In order to effectively implement technologies based on biological resources, it is necessary to construct small wastes solubilization or fertilizer installations at the site of waste generation, which will solve the problem of waste transport or sanitary hazards.

Bioaccessibility of lead in Dittrichia viscosa plants and risk assessment of human exposure around a fertilizer industry in Lebanon

Total and bioaccessible lead (Pb) concentrations in Dittrichia viscosa and soil samples were considered for estimating the potential health risk, related to both plant intake and accidental soil ingestion by adult and child consumers, near a Lebanese fertilizer plant. A total of 27 plant samples, from 9 uncultivated sites situated around the plant, were analyzed in order to assess the total and bioaccessible Pb content. Physiologically based extraction test (PBET) was used to estimate oral bioaccessibility of Pb in edible plant parts. Washed and unwashed leaves were compared in order to show the importance of good consumer practice on Pb intake. Extracted Pb in the intestinal medium accounted for 24 up to 87% of Pb extracted in the gastric medium. The total hazard quotient (HQ_tot) and the total bioaccessible hazard quotient (BHQ), related to both plants' intake and soil ingestion, for two maximalist child and adult scenarios, were calculated in order to estimate human health risk assessment. HQ_tot estimations considering the total concentration of Pb in soil and plant suggest that this metal is a contributor in elevating health risks problems on local plants' consumers, especially children inhabitants. However, the integration of bioaccessible concentrations of Pb in risk estimations reduces remarkably the potential risk.

Biomonitoring of genotoxicity of industrial fertilizer pollutants in Aiolopus thalassinus (Orthoptera: Acrididae) using alkaline comet assay

Phosphate fertilizer industry is considered as one of the main sources of environmental pollutants. Besides solid waste products, e.g. phosphates, sulphates, and heavy metals, also atmospheric pollutants, such as hydrofluoric acid fumes (HF), sulphur dioxide (SO₂), nitrogen oxides (NO₂), and particulate matter with diameter up to 10 μm (PM₁₀) can be dangerous. Genotoxic effect of these pollutants was monitored by assessing the DNA damage using alkaline comet assay on cells from brain, thoracic muscles and gut of Aiolopus thalassinus collected at three sites (A-C) located at 1, 3, and 6 km away from Abu-Zaabal Company for Fertilizers and Chemical Industries. Control site was established 32 km from the source of pollution, at the Cairo University Campus. The level of the DNA damage was significantly higher in insects from polluted sites comparing to that from the control site. A strong negative correlation between percentage of cells with visible DNA damage (% of severed cells) and the distance of the sites from Abu-Zaabal Company was found. The best parameter for monitoring of fertilizer pollutants is % of severed cells. Possible impact of Abu-Zaabal Company (extremely high concentration of phosphates and sulphates in all the polluted sites) on DNA integrity in A. thalassinus tissues was discussed. The potential use of the comet assay as a biomonitoring method of the environmental pollution caused by fertilizer industry was proposed. Specific pollution resulting from the activity of the fertilizer industry can cause comparable adverse effects in the organisms inhabiting areas up to 6 km from the source of contamination.