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Effect of Cd and Pb Pollutions on Physiological Growth: Wavelet Neural Network (WNN) as a New Approach on Age Determination of Coenobita scaevola

Nourouzi MM, Chamani A, Shirani M, Malekpouri P, Chuah AL

Bull Environ Contam Toxicol, 2018 Sep;101(3):320-325.
PMID: 30030595 DOI: 10.1007/s00128-018-2401-x

Environmental pollution of aquatic ecosystems leads to an interference in several fundamental biochemical and physiological functions. In this study the interference of Cd and Pb pollutions on the physiological growth and subsequently on the age determination was investigated. The hermit crab, Coenobita scaevola (C.s) was selected as a bioaccumulator in this study. The direct and indirect age determination methods were carried out using annual band counts and carapace length, respectively. The results showed that, there was very low correlation (R2 0.95). In addition, it was concluded that the environmental pollution had interaction with the growth physiology such as weight and length.

Matched MeSH terms: Environmental Pollution
Implication of Physiological and Biochemical Variables of Prognostic Importance in Lead Exposed Subjects

Malik A, Ashraf MAB, Khan MW, Zahid A, Shafique H, Waquar S, et al.

Arch Environ Contam Toxicol, 2020 Apr;78(3):329-336.
PMID: 31620805 DOI: 10.1007/s00244-019-00673-2

The use of leaded gasoline adversely affects cardiovascular, nervous, and immune systems. Study projects to rule out different variables of prognostic importance in lead-exposed subjects. A total of 317 traffic wardens with 5 years of outdoor experience and Hb levels

Matched MeSH terms: Environmental Pollution
Effects of Soil Amendments on Microbial Activities in a Typical Cd-Contaminated Purple Field Soil, Southwestern China

Wang W, Zhou F, Chang Y, Cui J, He D, Du J, et al.

Bull Environ Contam Toxicol, 2020 Mar;104(3):380-385.
PMID: 31932904 DOI: 10.1007/s00128-020-02786-0

In this study, three soil amendments (inorganic, liming, or organic-inorganic materials) were used in a Cd-contaminated purple field soil to investigate their impacts on soil Cd availability, enzyme (urease, catalase, sucrase, and acid phosphatase) activities, microbial biomass (carbon/nitrogen) and type (bacteria, fungi, and actinomycetes) in mustard and corn trials. Results showed that soil amendments generally decreased soil exchangeable Cd, fungi and bacterial populations while increasing the activities of all the four soil enzymes tested, microbial biomass carbon and populations of actinomycetes (p 0.05) whereas stronger effects appeared in soil organic matter and available nutrients (nitrogen, phosphorous and potassium; p

Matched MeSH terms: Environmental Pollution
Evaluating the Potential of Oleaginous Yeasts as Feedstock for Biodiesel Production

Mukhtar H, Suliman SM, Shabbir A, Mumtaz MW, Rashid U, Rahimuddin SA

Protein Pept Lett, 2018;25(2):195-201.
PMID: 29359654 DOI: 10.2174/0929866525666180122112805

BACKGROUND: Lipid-producing microorganisms, said to be oleaginous have been recognized since several years. We had investigated the effects of medium components and culturing situations on cell growth and lipid accumulation of oleaginous yeasts which were analytically examined so as to enhance lipid yield for biodiesel production.
OBJECTIVE: The main objective of this study was to explore oleaginous yeast, Yarrowia lipolytica isolated from soil and optimization of culture conditions and medium components to obtained better quality microbial oil for biodiesel production.
METHODS: Fifty yeast strains were isolated from soil from different regions of Lahore and eleven of them were selected for oil production. The isolated yeast colonies were screened to further check their lipid producing capabilities by the qualitative analysis. Five yeast strains were designated as oleaginous because they produced more than 16% of oil based on their biomass. To estimate the total lipid content of yeast cells, the extraction of lipids was done by performing the procedure proposed by Bligh and Dyer. The transesterification of yeast oils was performed by using different methods. There were three different strategies customized to transesterifying microbial oil using base catalyzed transesterification, acid catalyzed transesterification and enzyme-based transesterification. After completion of transesterification, sample was used for fatty acid methyl esters (FAMEs) were analyzed by gas-chromatograph with ionization detector type MS.
RESULTS: The isolate IIB-10 identified as Yarrowia lipolytica produced maximum amount of lipids i.e. 22.8%. More amount of biomass was obtained when cane molasses was utilized as carbon source where it produced 29.4 g/L of biomass while sucrose and lactose were not utilized by IIB-10 and no biomass was obtained. Similarly, meat extracts showed best results when it was used as nitrogen source because it resulted in 35.8 g/L biomass of Yarrowia lipolytica IIB-10. The culturing conditions like size of inoculum, effect of pH and time of incubation were also studied. The 10% of inoculum size produced 25.4 g/L biomass at 120 h incubation time, while the pH 7 was the optimum pH at which 24.8 g/L biomass was produced by Yarrowia lipolytica IIB-10. GC-MS analysis showed that biodiesel produced by transesterification contained similar fatty acids as found in vegetable oil for this reason it is widely accepted feedstock for biodiesel production.
CONCLUSION: The analysis of fatty acids methyl esters showed the similar composition of microbial oil as in vegetable oils and high amount of methyl esters were obtained after transesterification. Therefore, potentially oleaginous yeast could be used to generate a large amount of lipids for biodiesel production that will be the better substitute of petroleum-based diesel and will also control the environmental pollution.

Matched MeSH terms: Environmental Pollution
Assessment of toxic metals in water and sediment of Pasur River in Bangladesh

Ali MM, Ali ML, Islam MS, Rahman MZ

Water Sci Technol, 2018 Mar;77(5-6):1418-1430.
PMID: 29528329 DOI: 10.2166/wst.2018.016

This study was conducted to assess the levels of toxic metals like arsenic (As), chromium (Cr), cadmium (Cd), and lead (Pb) in water and sediments of the Pasur River in Bangladesh. The ranges of Cr, As, Cd, Pb in water were 25.76-77.39, 2.76-16.73, 0.42-2.98 and 12.69-42.67 μg/L and in sediments were 20.67-83.70, 3.15-19.97, 0.39-3.17 and 7.34-55.32 mg/kg. The level of studied metals in water samples exceeded the safe limits of drinking water, indicating that water from this river is not safe for drinking and cooking. Certain indices, including pollution load index (PLI) and contamination factor (Cif) were used to assess the ecological risk. The PLI indicated progressive deterioration of sediments by the studied metals. Potential ecological risks of metals in sediment indicated low to considerable risk. However, the Cif values of Cd ranged from 0.86 to 8.37 revealed that the examined sediments were strongly impacted by Cd. Considering the severity of potential ecological risk (PER) for single metal (Eir), the descending order of contaminants was Cd > Pb > As > Cr. According the results, some treatment scheme must formulate and implement by the researchers and related management organizations to save the Pasur River from metals contamination.

Matched MeSH terms: Environmental Pollution
Remediation of Pb/Cr co-contaminated soil using electrokinetic process and approaching electrode technique

Ng YS, Sen Gupta B, Hashim MA

Environ Sci Pollut Res Int, 2016 Jan;23(1):546-55.
PMID: 26330317 DOI: 10.1007/s11356-015-5290-0

Electrokinetic process has emerged as an important tool for remediating heavy metal-contaminated soil. The process can concentrate heavy metals into smaller soil volume even in the absence of hydraulic flow. This makes it an attractive soil pre-treatment method before other remediation techniques are applied such that the chemical consumption in the latter stage can be reduced. The present study evaluates the feasibility of electrokinetic process in concentrating lead (Pb) and chromium (Cr) in a co-contaminated soil using different types of wetting agents, namely 0.01 M NaNO3, 0.1 M citric acid and 0.1 M EDTA. The data obtained showed that NaNO3 and citric acid resulted in poor Pb electromigration in this study. As for Cr migration, these agents were also found to give lower electromigration rate especially at low pH region as a result of Cr(VI) adsorption and possible reduction into Cr(III). In contrast, EDTA emerged as the best wetting agent in this study as it formed water-soluble anionic complexes with both Pb and Cr. This provided effective one-way electromigration towards the anode for both ions, and they were accumulated into smaller soil volume with an enrichment ratio of 1.55-1.82. A further study on the application of approaching cathode in EDTA test showed that soil alkalisation was achieved, but this did not provide significant enhancement on electromigration for Pb and Cr. Nevertheless, the power consumption for electrokinetic process was decreased by 22.5%.

Matched MeSH terms: Environmental Pollution
Use of sterols and linear alkylbenzenes as molecular markers of sewage pollution in Southeast Asia

Thomes MW, Vaezzadeh V, Zakaria MP, Bong CW

Environ Sci Pollut Res Int, 2019 Nov;26(31):31555-31580.
PMID: 31440968 DOI: 10.1007/s11356-019-05936-y

Southeast Asia has undergone rapid developments in terms of urbanization, economic and population growth. The progress in sewerage treatment infrastructure has not kept pace with such developments. The inadequacy and inefficiency of sewerage systems has prompted the release of untreated sewage into the aquatic environment of Southeast Asia causing many waterborne illnesses since surface water is utilized for recreational, agricultural and aquaculture purposes and, above all, as a source of water intake in Southeast Asia. This paper will review the current data on molecular markers of sewage pollution including sterols and linear alkylbenzenes (LABs) in Southeast Asian aquatic environment to clarify the state of sewage pollution and the competence of sewage treatment plants (STPs) in this area. Despite the importance of sewage pollution research in the region, the number of studies using molecular markers to trace the sources of sewage pollution is limited. So far, indicators of sewage pollution have been investigated in aquatic environments of Indonesia, Vietnam, Malaysia, the Philippines, Thailand, Cambodia and Brunei among Southeast Asian countries. The concentrations and diagnostic ratios of faecal sterols and LABs show the release of untreated and primary treated urban waste into water bodies of these countries. Further studies are required to fill the data gaps in Southeast Asia and come to a better understanding of the trends of sewage pollution in this part of the world. Graphical abstract.

Matched MeSH terms: Environmental Pollution
Fulltext Microplastics Pollution as an Invisible Potential Threat to Food Safety and Security, Policy Challenges and the Way Forward

Usman S, Abdull Razis AF, Shaari K, Amal MNA, Saad MZ, Mat Isa N, et al.

Int J Environ Res Public Health, 2020 Dec 21;17(24).
PMID: 33371479 DOI: 10.3390/ijerph17249591

Technological advances, coupled with increasing demands by consumers, have led to a drastic increase in plastic production. After serving their purposes, these plastics reach our water bodies as their destination and become ingested by aquatic organisms. This ubiquitous phenomenon has exposed humans to microplastics mostly through the consumption of sea food. This has led the World Health Organization (WHO) to make an urgent call for the assessment of environmental pollution due to microplastics and its effect on human health. This review summarizes studies between 1999 and 2020 in relation to microplastics in aquatic ecosystems and human food products, their potential toxic effects as elicited in animal studies, and policies on their use and disposal. There is a paucity of information on the toxicity mechanisms of microplastics in animal studies, and despite their documented presence in food products, no policy has been in place so far, to monitor and regulates microplastics in commercial foods meant for human consumption. Although there are policies and regulations with respect to plastics, these are only in a few countries and in most instances are not fully implemented due to socioeconomic reasons, so they do not address the problem across the entire life cycle of plastics from production to disposal. More animal research to elucidate pathways and early biomarkers of microplastic toxicity that can easily be detected in humans is needed. This is to create awareness and influence policies that will address this neglected threat to food safety and security.

Matched MeSH terms: Environmental Pollution
[Sanitary and environmental engineering: the importance of planning in regard to health needs]

Horwitz A

Bol Oficina Sanit Panam, 1986 Sep;101(3):193-207.
PMID: 2944521
Matched MeSH terms: Environmental Pollution
Geochemical and mineralogical assessment of sedimentary limestone mine waste and potential for mineral carbonation

Mohd Isha NS, Mohd Kusin F, Ahmad Kamal NM, Syed Hasan SNM, Molahid VLM

Environ Geochem Health, 2021 May;43(5):2065-2080.
PMID: 33392897 DOI: 10.1007/s10653-020-00784-z

This paper attempts to evaluate the mineralogical and chemical composition of sedimentary limestone mine waste alongside its mineral carbonation potential. The limestone mine wastes were recovered as the waste materials after mining and crushing processes and were analyzed for mineral, major and trace metal elements. The major mineral composition discovered was calcite (CaCO3) and dolomite [CaMg(CO3)2], alongside other minerals such as bustamite [(Ca,Mn)SiO3] and akermanite (Ca2MgSi2O7). Calcium oxide constituted the greatest composition of major oxide components of between 72 and 82%. The presence of CaO facilitated the transformation of carbon dioxide into carbonate form, suggesting potential mineral carbonation of the mine waste material. Geochemical assessment indicated that mean metal(loid) concentrations were found in the order of Al > Fe > Sr > Pb > Mn > Zn > As > Cd > Cu > Ni > Cr > Co in which Cd, Pb and As exceeded some regulatory guideline values. Ecological risk assessment demonstrated that the mine wastes were majorly influenced by Cd as being classified having moderate risk. Geochemical indices depicted that Cd was moderately accumulated and highly enriched in some of the mine waste deposited areas. In conclusion, the limestone mine waste material has the potential for sequestering CO2; however, the presence of some trace metals could be another important aspect that needs to be considered. Therefore, it has been shown that limestone mine waste can be regarded as a valuable feedstock for mineral carbonation process. Despite this, the presence of metal(loid) elements should be of another concern to minimize potential ecological implication due to recovery of this waste material.

Matched MeSH terms: Environmental Pollution
Gut bacteria of animals living in polluted environments exhibit broad-spectrum antibacterial activities

Akbar N, Siddiqui R, Sagathevan K, Khan NA

Int Microbiol, 2020 Nov;23(4):511-526.
PMID: 32124096 DOI: 10.1007/s10123-020-00123-3

Infectious diseases, in particular bacterial infections, are the leading cause of morbidity and mortality posing a global threat to human health. The emergence of antibiotic resistance has exacerbated the problem further. Hence, there is a need to search for novel sources of antibacterials. Herein, we explored gut bacteria of a variety of animals living in polluted environments for their antibacterial properties against multi-drug resistant pathogenic bacteria. A variety of species were procured including invertebrate species, Blaptica dubia (cockroach), Gromphadorhina portentosa (cockroach), Scylla serrata (crab), Grammostola rosea (tarantula), Scolopendra subspinipes (centipede) and vertebrate species including Varanus salvator (water monitor lizard), Malayopython reticulatus (python), Cuora amboinensis (tortoise), Oreochromis mossambicus (tilapia fish), Rattus rattus (rat), Gallus gallus domesticus (chicken) and Lithobates catesbeianus (frog). Gut bacteria of these animals were isolated and identified using microbiological, biochemical, analytical profiling index (API) and through molecluar identification using 16S rRNA sequencing. Bacterial conditioned media (CM) were prepared and tested against selected Gram-positive and Gram-negative pathogenic bacteria as well as human cells (HaCaT). The results revealed that CM exhibited significant broad-spectrum antibacterial activities. Upon heat inactivation, CM retained their antibacterial properties suggesting that this effect may be due to secondary metabolites or small peptides. CM showed minimal cytotoxicity against human cells. These findings suggest that gut bacteria of animals living in polluted environments produce broad-spectrum antibacterial molecule(s). The molecular identity of the active molecule(s) together with their mode of action is the subject of future studies which could lead to the rational development of novel antibacterial(s).

Matched MeSH terms: Environmental Pollution