Refine search
Results 31-40 of 572
Evaluation of the phytotoxicity of a pesticide (TRACTOR 10E) based on Alpha-cypermethrin in two plant species: lentils (Lens culinaris) and watercress (Lepidium sativum)
2023
Ayoub, Naamane | Nawal, Lamraouhi | Soumaya, Rafii | Nadia, Iounes | Amrani Souad, El
Tractor 10E is an Alpha-cypermethrin based insecticide. It is one of the commonly used insecticides. The toxic effect of this product was assessed using the Lens culinaris (edible lentil) and Lepidium sativum (watercress) test. The seeds of Lens culinaris and Lepidium sativum were subjected to 6 increasing concentrations of Tractor 10E (25, 50, 100, 200, 400 and 800mg/l) and the control (distilled water). After 7 days, weight, root and stem development were measured.The results of the statistical study revealed the notable effect of this toxic product on growth, especially at high concentrations for the two species which are the subject of plant toxicity tests. Stem length growth is the most sensitive parameter. IC50 is equal to 136.99mg/l for lentil and 136.42mg/l for watercress. The results of this study reveal that this alpha-cypermethrin insecticide has the ability to alter the growth of plants as non-target organisms, which imposes the effective use and management of these toxicants and even replacing them with biopesticides to preserve human health and the environment.
Show more [+] Less [-]Bioaccumulation of Heavy Metals in Marcia recens, an Edible Bivalve of Ashtamudi Lake, a Ramsar Site (1204), India
2023
Narayanankutty, Parvathy | Balakrishnan Thamarakshi, Sulekha | Sasidharan, Sheeba
As a RAMSAR site (no.1204), Ashtamudi Lake has very productive and significant ecosystem services. Currently, the lake is being threatened by severe pollution stress, especially with heavy metals. Heavy metal pollution is a great concern of matter as it enters in the bioaccumulation and bio-magnification processes of the aquatic food chain. The present study seasonally investigated the bioaccumulation of seven heavy metals (Pb, Zn, Fe, Cu, Cr, Cd and Co) in the body tissues of an edible bivalve, Marcia recens, from three sampling stations (viz. Neendakara, Kureepuzha and Asramam) of the lake during the study period in 2019. The results showed that, as per the standard permissible limits (FAO/USEPA, 1989), some of the metal accumulations were extremely high in the bivalve tissues. Highest Metal Pollution Index was observed in station Ⅱ. There were significant spatial and temporal variations in the accumulation of heavy metals in the the examined bivalve. Two way ANOVA analysis also reveals a statistically significant differences (p<0.5), in the heavy metal accumulation in the bivalve, among the stations as well as seasons. The continual exposure to even a relatively low levels of these metals by regular consumption of contaminated bivalves, may entail adverse health issues. Implementation of appropriate scientific and sustainable conservation strategies will ensure the health of the estuaries and the sustainability of bio-resources.
Show more [+] Less [-]Reducing Environmental Pollutants by using Triorganotin(IV)-Tyrosine Complexes that Prolong the Life of the Polymers used in Outdoor Patios
2023
R. Arraq, Rafid | G. Hadi, Angham | S. Ahmed, Dina | Zainulabdeen, Khalid | Hashim, Hassan | A. Ahmed, Ahmed | M. Yusop, Rahimi | H. Jawad, Ali | A. Mohammed, Salam | Al-Amiery, Ahmed | Yousif, Emad
When exposed to UV light at ambient temperature, three tri organotin (IV) complexes with tyrosine as a ligand (85–97% yields) were utilized as additives to prevent the photo-degradation of PVC films (40 μm thickness). The compounds were described using NMR (1H, 13C and 119Sn), IR, and elemental analysis. The compounds formed were assigned trigonal bipyramidal geometry depending on the spectrum data. Several Triorganotin (IV) tyrosine complexes were synthesized and mixed with polymers to form thin films (vinyl chloride). Up to 300 hours of UV light (wavelength: 313 nm) exposure was given to these films. A microscope, atomic force microscopy, and scanning electron microscopy were used to examine the surface morphology of the PVC films. Rapid UV-weathering was employed to determine weight loss and the production of certain functional groups, including carbonyl and polyene. Compared to pure PVC film, the films with manufactured complexes showed less undesired alterations. By absorbing UV light and scavenging peroxides, hydrochlorides and radicals. The polymer was photo stabilized by the triorganotin (IV)-tyrosine complexes (vinyl chloride). It was discovered that Ph3SnL has the fastest rate of PVC photostabilization.
Show more [+] Less [-]Fuzzy Inference of Air Quality – A case study of Vadodara City
2023
Seema, Nihalani
Abstract: Air Quality Index (AQI) is derived from a series of observations of different air pollutants for reporting air quality. The severity of air pollution and its impacts on the general public are typically reported using the air quality index. Different methods have been developed by various regulatory agencies and scientists, to calculate the AQI using aggregation methods involving critical pollutants. This paper presents a comparison between conventional AQI and Fuzzy AQI. 20 sampling locations were chosen for Vadodara city in order to investigate the effects of urban air pollution, and ambient air quality was measured twice a week from October 2017 to February 2018. The Central Pollution Control Board (CPCB) method formulas were used to calculate the traditional Air Quality Index using the measured values of Coarse particulate matter (PM10), Sulphur dioxide (SO2), and Oxides of nitrogen (NOX). Additionally, the membership functions were provided as input to the Mamdani fuzzy inference system (FIS) for the fuzzy logic system, and the fuzzy air quality index (FAQI) was calculated. The computed conventional AQI values were compared with FAQI values. A close co-relation was observed between conventional AQI and fuzzy AQI values. The application of the fuzzy inference system demonstrates its capability to manage difficult issues including data ambiguity. The findings clearly show that the FIS is capable of resolving inherent discrepancies and interpreting complex conditions.
Show more [+] Less [-]Performance Evaluation of Different Soil Media by Batch-Operated Pilot-Scale Horizontal Subsurface Flow Constructed Wetlands for Wastewater Treatment
2023
Kumar Swarnakar, Arvind | Bajpai, Samir | Ahmad, Ishtiyaq
Constructed wetland systems (CWs) are low-cost natural treatment systems for various types of influents. Although mainly the natural wetlands are soil-based, the constructed wetlands have been traditionally built using aggregate media. The performance of four types of available soils in Chhattisgarh was studied as the filter media in the horizontal subsurface flow-constructed wetland (HSFCW). Fourteen pilot-scale CW units with different soil types (entisol, vertisol, alfisol, inceptisol, and stone aggregate) and plant types (Canna indica and Typha latifolia) were used to treat domestic wastewater (WW). One set of each soil base reactor was planted with Canna indica and Typha latifolia, and one was kept blank (unplanted). All soils and plants are easily available.The reactors received primary wastewater in batch loads with WW loading for six hours to maintain aerobic conditions. The residence time of WW was 48 hours, and the applied hydraulic loading rate (HLR) was based on soil and aggregate. According to the findings, the planted HSFCW was more effective than the unplanted system. The results show that the wetland constructed on the treatment efficiency of the soil base has excellent potential to treat WW, with both plants.
Show more [+] Less [-]Biochar Derived from the Husk and Straw of Rice (Oryza sativa L.) Produced via Low-Temperature Pyrolysis as an Effective Adsorbent for Pb (II) Removal
2023
Chaijak, Pimprapa | Michu, Panisa | Thipraksa, Junjira | Kongthong, Alisa
Pyrolysis is a promising thermochemical conversion process that transforms biomass into biochar, a carbon-rich solid material, in an oxygen-limited environment. This study focuses on the utilization of rice byproducts, namely rice straw and rice husk as feedstock for biochar production through low-temperature pyrolysis. The aim is to explore the potential of these biochars as cost-effective adsorbents for removing metal contaminants from aqueous solutions, with a particular emphasis on Pb(II) removal. Physicochemical properties of the biochars produced at a low temperature of 300 °C were thoroughly investigated, including surface morphology and their adsorption capacity for Pb(II). Remarkably, the rice straw biochar (RSB) produced at 300 °C exhibited exceptional Pb(II) adsorption capacity, with a value of 390.10±0.30 mg/g, and demonstrated a high Pb(II) removal efficiency of 96.10±0.30% when modified with 30% w/w H2O2. A crucial aspect of this study lies in the evaluation of the cost-effectiveness of the biochar production process, particularly when compared to commercially available adsorbents. By demonstrating the potential of rice byproduct-derived biochar as an efficient Pb(II) biosorbent in aqueous environments, this work not only provides new insights into the preparation of biochar using low-temperature pyrolysis but also offers a viable and economical solution for metal-contaminated water treatment. The findings of this research contribute to the field of sustainable waste utilization and highlight the significant potential of rice byproduct-based biochar as an environmentally friendly adsorbent for heavy metal removal.
Show more [+] Less [-]Status, Health Effects and Remediation Techniques of E-waste – A Review
2023
Guin, Shailu | Deswal, Surinder
The annual global generation of e-waste is estimated to be 59.08 million tonnes (7.37 kg per capita), out of which the major chunk is being processed in informal sector using primitive and hazardous methods in developing countries due to cheap labour, less stringent laws and regulatory policies. Despite the fact the annual global value of e-waste industry being about USD 62.5 billion that provides employment to millions in developing countries, the unstructured/informal operations in e-waste sector had and have been causing hazardous health issues in human and environment along with unlawful activities. Many studies have been reported on wide array of interrelated aspects and issues of e-waste, but only few studies have reviewed potential remediation techniques that can take care of the increasing e-waste and its sustainable management. Therefore, disposal and remediation techniques for polluted sites have been the key concerns in the field of environmentally sustainable management (ESM) of e-waste. The present review revealed that of all the classic and hybrid remediation techniques, the biological remediation techniques being eco-friendly and cost effective needs to be explored for metal removing from contaminated environment. The review also concludes the imminent necessity of ESM by framing and implementing regulations and laws essentially incorporating Extended Producer Responsibility (EPR) in developing countries. The review of Indian scenario suggests the scope of startups for the sustainable recycling of e-waste to achieve healthy environment, employment and economic opportunities.
Show more [+] Less [-]A Review on Global Pesticide Use and Food Contamination: African Perspective
2023
Adebisi, Fagbohun | Dauda, Mary | Anjorin, Toba
Pesticide application has increased globally with increasing demand for food, and modernized Agriculture as a result of an explosion in the world’s population growth, especially in developing nations in Africa, Asia, and South America. However, pesticides have helped to improve productivity, protect the nutritive integrity of food crops, and ensure year-round food supplies worldwide. The production and consumption of pesticides persisted from one decade to another until the ecosystem started to suffer from its adverse effects on the environment and human health. Previous investigations revealed that pesticides found entry into the human food chain. In response to these problems, researchers all over the world have conducted several kinds of research on pesticide applications, and their residual contamination in food. This review crosses from the past to present researches on the usage of pesticides, their accumulation in food, and possible methods of their reduction as highlighted by researchers over many years. There is a need for continuous monitoring of pesticide residue profile in soil, crop produce, and animal products in developing countries so that it will not exceed maximum residue limits (MRLs).
Show more [+] Less [-]Treatment of Fish Processing Wastewater by Alum and PAM: A Comparative Study on Turbidity, COD, BOD, and Rheological Properties
2023
AL Riyami, Hanan Ahmed Said | Al Dawery, Salam Kadhim | Reddy, Sreedhar | Ahmed, Anwar
This research article compares the efficacy of using alum and poly aluminum chloride (PAM) for the treatment of fish processing wastewater. This study aims to determine the effectiveness of each treatment method in reducing turbidity, COD), BOD, and altering the rheological properties of the wastewater. Batch mode coagulation and flocculation experiments were conducted using lab scale jar test apparatus. The findings indicate that both alum and PAM can significantly reduce turbidity and COD. The highest turbidity removal efficiency of 93% was achieved with alum at a dose of 200 mg/L, while PAM achieved a maximum turbidity removal efficiency of 86% at a dose of 100 mg/L. Alum and PAM achieved the highest BOD5 and COD removal efficiencies at a dosage of 200 mg/L and pH 7.0. However, the removal efficiencies varied at different pH values and dosages. Alum and PAM have significant effect on the rheological properties of fish processing wastewater. The viscosity of settled residual sludge after chemical coagulation is more compared to untreated fish processing wastewater due to aggregation of suspended particles to form larger flocs. This would improve the settling properties of the coagulated sludge. The study concludes that both alum and PAM can be viable options for treating fish processing wastewater, with Alum showing a slight edge over PAM in certain aspects.
Show more [+] Less [-]Catalytic Conversion of Carbon Dioxide by Metal-Organic Frameworks: an Effective Approach for CO2 Utilization
2023
Tayebi, Leila | Rahimi, Rahmatollah | Akbarzadeh, Ali Reza
Due to the increase in carbon dioxide emission, there is a need for achieving efficient ways to reduce CO2 harmful effects. There are several strategies to mitigate atmospheric CO2 concentration. The catalytic cycloaddition of carbon dioxide with epoxides to provide cyclic carbonates employing metal-organic frameworks is a promising method for this purpose. Herein the application of two porous porphyrinic MOFs (Co-PMOF and Cu-PMOF) as catalysts in CO2 conversion was investigated. These MOFs demonstrated good crystallinity and porosity, providing them with two promising platforms to study CO2 conversion reactions. These heterogeneous porphyrin-based MOFs are catalytically efficient towards the chemical conversion of CO2 under moderate conditions because these MOF matrices contain a high density of active Lewis acidic and basic sites for activating CO2 and epoxide compounds. These MOFs exhibited high catalytic efficiency for the chemical fixation of CO2 at ambient temperature and solvent-free conditions. The reactions formed the proportionate cyclic carbonates in good yields. These products are valuable compounds in a variety of chemical fields.
Show more [+] Less [-]