Evaluation of Environmental Pollution and Microbial Treatment of Shallow Groundwater in El Omayed Area, Egypt

Abstract

In the last few years, the northwestern coastal zone of Egypt has been affected by many stresses that impact its water resources, leading to undesirable consequences related to water quantity and quality. This paper aims to evaluate the possible contamination sources of shallow aquifers in the El‐Omayed area, Egypt, that are causing its deterioration; this was achieved through an integration of hydrochemical and isotopic techniques, an assessment of the undesirable consequences of potential toxic metals (PTMs) on human health risk as a result of direct water consumption, and finally, the application of biological treatment in the remediation of some metal contamination. The chemical composition, environmental isotopes (δ18O and δ2H), and microbial analyses were analyzed from 13 collected water samples. Approximately 20% of the groundwater samples were classified as fresh water, and the rest were classified as slightly saline to moderately saline. Stable isotopes proved the contribution of the El Sheikh Zoied canal (which is mainly recharged from the Nile system) as a recharge source. The toxicity of PTMs (Cd, Cu, Co, Cr, Pb, Zn, B, and Fe) was evaluated on the basis of their exceedance values. It was proven that the majority of the groundwater samples were contaminated, which might be attributed to natural and anthropogenic actions in the study area; however, according to human health risk exposure assessment calculations, there is no human cancer risk posed via ingestion of drinking groundwater. The total bacterial count was determined for all water samples; autochthonous microorganisms were capable of removing heavy metals in the polluted water sample. The bacterial strain M52, which was identified by 16S rRNA sequencing as Stenotrophomonas rhizophila, showed the best results, by removing 75% and 65% of the initial concentrations of Fe and B, respectively. The results indicate that this bacterial strain may be useful and represents an environmentally friendly method to remove pollutants and heavy metals from contaminated water. Integr Environ Assess Manag 2020;16:461–471. © 2020 SETAC

Analysis of endometrial lavage microbiota reveals an increased relative abundance of the plastic-degrading bacteria Bacillus pseudofirmus and Stenotrophomonas rhizophila in women with endometrial cancer/endometrial hyperplasia

“…The results of our analysis therefore suggest that the endometrial microbiota may respond peculiarly to increasing exposure to environmental pollutants. Interestingly, both LDPE and certain heavy metals -degraded and removed by Bacillus pseudo rmus [19,20] and Stenotrophomonas rhizophila [23], respectively -may mimic the effect of estrogens and act as endocrine disrupting chemicals promoting endometrial carcinogenesis [24,25]. This is, to our knowledge, the rst study to show that the extent of colonization by these two bacterial species is higher in the endometrial lavage microbiota of women with EH/EC.…”

“…Bacillus pseudo rmus is a facultative aerobic alkaliphile bacterium characterized by the ability to degrade inert polyethylene-based plastics, including low-density polyethylene (LDPE) [19,20]. Additionally, the species Stenotrophomonas rhizophila is an e cient degrader of polyvinyl alcohol [22] and can remove heavy metals from contaminated water [23].…”

Analysis of endometrial lavage microbiota reveals an increased relative abundance of the plastic-degrading bacteria Bacillus pseudofirmus and Stenotrophomonas rhizophila in women with endometrial cancer/endometrial hyperplasia

“…On the one hand, Bacillus pseudofirmus is a facultative aerobic alkaliphile bacterium characterized by the ability to degrade inert polyethylene-based plastics, including low-density polyethylene (LDPE) ( Dela Torre et al., 2018 ; Atanasova et al., 2021 ). On the other hand, Stenotrophomonas rhizophila is not only an efficient degrader of polyvinyl alcohol ( Wei et al., 2018 ) but can also remove heavy metals from contaminated water ( Hagagg et al., 2020 ). We speculate that these two bacterial species may be enriched in the uterine microbiota of women with EC/EH as a result of an increased exposure to environmental pollutants.…”

“…Importantly, our results highlight the need to include uterine lavage fluid as target samples in studies exploring the impact of plastic contamination on women’s health. Both LDPE and certain heavy metals, which are degraded and removed by Bacillus pseudofirmus ( Dela Torre et al., 2018 ; Atanasova et al., 2021 ) and Stenotrophomonas rhizophila ( Hagagg et al., 2020 ), respectively, may act as estrogen-mimicking endocrine disruptors to promote endometrial carcinogenesis ( Yang et al., 2011 ; Rzymski et al., 2015 ). Interestingly, Taiwan is characterized by a markedly high daily intake of estrogen-like pollutants ( Lu et al., 2007 ).…”

Impact of microecological agents on water environment restoration and microbial community structures of trench system in a Baiyangdian wetland ecosystem

“…For example, Xia et al (2020) studied the mechanism of calcium peroxide slow‐release materials for phosphorus fixation in river water and phosphorus control in sediments and found that such materials exert a dual remediation effect by controlling the rate of oxygen release and stabilizing pH, causing the total dissolved phosphorus in the overlying water to be deposited to the sediment in the forms of Al‐P, Ca‐P and Fe‐P, thereby blocking the release of endogenous phosphorus from the sediment to the water column and absorbing phosphorus from the water column. Gan et al (2020) constructed a laboratory‐scale, continuous, up‐flow‐immobilized biofilter based on immobilized colonies of polyurethane foam carriers and demonstrated a denitrification rate of 198.40 ± 4.50 g (m −3 day −1 ) for 14–18 mg N L −1 nitrogen‐contaminated waters at a hydraulic retention time of only 1.8 h. On the contrary, Hagagg et al (2020) found that Stenotrophomonas rhizophila was able to remove 75% of iron and 65% of boron from water bodies by remediation of harmful substances in the shallow surface layer of the El‐Omayed area, which has a good potential for remediation of polluted water bodies. Microecological agents have also been widely used in the treatment of aquaculture waters (Xiang et al, 2012), but their application in natural water bodies is still in its infancy.…”