Chitosan-based beads as sustainable adsorbents for wastewater remediation: a review

Environmental Chemistry Letters - Water contamination is increasing worldwide, yet actual methods of water and wastewater treatment are limited, in particular by actual fossil-fuel derived...     

Isoprene Emission from the Forest of Haryana State

Tropical and sub tropical regions are regarded as dominant source of biogenic volatile organic compounds emission (BVOC). However, measurement studies from these regions are limited and largely confined to South Africa and Amazonia. Consequently, global BVOC estimates are mainly based on modeling studies. Moreover, BVOC emission estimate is altogether lacking for any region of the Indian sub continent. This study attempts to estimate isoprene emission capacity of forest of Haryana state. Individual plant species isoprene emission capacity is found to vary from below detection limit (BDL) to 12.01 mg Cm^{− 2} h^{− 1}. Maximum emission capacity (12.01 mg Cm^{− 2} h^{− 1}) is noticed in case of Dalbergia sissoo. The area average isoprene emission capacity for the Haryana forest is found to be 19.98 mg Cm^{− 2} h^{− 1}, which is significantly (2.4 times) higher than the reported isoprene emission value of 8.2 mg Cm^{− 2} h^{− 1} for the Kalahari woodland of Africa.     

In vitro cytogenetic assessment of trichloroacetic acid in human peripheral blood lymphocytes

Trichloroacetic acid (TCA), a common water disinfection byproduct and a persistent metabolite of trichloroethylene (TCE), has been examined for its genotoxic potential in human lymphocytes. Chromosomal aberration (CA) and cytokinesis-block micronucleus (CBMN) assay were employed to assess the toxicity of TCA. Lymphocytes obtained from three healthy donors were exposed to 25, 50, and 100 μg/ml concentration of TCA separately. TCA exposure resulted in chromosomal anomalies and the formation of micronuclei in lymphocytes. Chromosome analysis revealed the dose-dependent and significant induction of CA. Chromatid break/chromosome break, fragments, and chromatid exchanges were commonly observed. Exposure of higher concentration (50 and 100 μg/ml) significantly inhibited mitotic index. Data obtained with CBMN assay indicated that the induction of micronucleus (MN) formation was greater than that of CA. At 25 μg/ml, TCA induced significant frequencies of MN as compared to control cells. Significant induction of MN at the lowest concentration indicates TCA may also interact with mitotic spindles. Lower percentage of CA and MN at 100 μg/ml as compared to 50 μg/ml indicates occurrence of severe cytotoxicity on exposure of 100 μg/ml TCA in lymphocytes. Collectively, results of both cytogenetic assays indicate that exposure of TCA can induce significant genotoxic and cytotoxic effects.     

Altitude distribution of aerosols over Southeast Arabian Sea coast during pre-monsoon season: Elevated layers,long-range transport and atmospheric radiative heating

Every year, during the pre-monsoon period (March–May), a pronounced increase in aerosol optical depth (AOD) is observed over the eastern Arabian Sea, which is attributed to the transport of continental aerosols. This paper presents the altitude distribution of tropospheric aerosols, characteristics of elevated aerosol layers and aerosol radiative heating of the atmosphere during the pre-monsoon season over Trivandrum (8.5°N, 77°E), a station located at the southwest coast of Indian peninsula which is covered by the eastern Arabian Sea plume. Altitude profiles of aerosol backscatter coefficient (β_a) and linear depolarization ratio (LDR) reveal two distinct aerosol layers persisting between 0–2 km and 2–4 km. The layer at 2–4 km, which contributes about 25% of the AOD during polluted conditions, contains significant amount of non-spherical aerosols. This layer is prominent only when the advection of dry airmass occurs from the northern parts of the Indian subcontinent and northern Arabian Sea. Role of long-range transport in the development of this aerosol layer is further confirmed using latitude–altitude cross-section of β_a observed by CALIPSO. Aerosol content in the layer below 2 km is large when advection of air occurs from the north and east Arabian Sea and is significantly small when it occurs from the southwest Arabian Sea or Indian Ocean. During the highly polluted conditions, aerosols tend to increase the diurnal mean atmospheric radiative heating rate by ～0.8 K day^?1 at 500 m and 0.3 K day^?1 at 3 km, which are about 80% and 30% of the respective radiative heating in the aerosol-free atmosphere.     

Berberine-loaded liquid crystalline nanoparticles inhibit non-small cell lung cancer proliferation and migration in vitro

Environmental Science and Pollution Research - Non-small cell lung cancer (NSCLC) is reported to have a high incidence rate and is one of the most prevalent types of cancer contributing towards 85%...     

Effective removal of doxycycline from aqueous solution using CuO nanoparticles decorated poly(2-acrylamido-2-methyl-1-propanesulfonic acid)/chitosan

Environmental Science and Pollution Research - The primary focus of the present study was to synthesize CuO nanoparticles decorated poly(2-acrylamido-2-methyl-1-propanesulfonic acid)/chitosan to...     

Assessment of persistent organic pollutants in soil and sediments from an urbanized flood plain area

Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and phenolic compounds (PCs) are persistent organic compounds. Contamination of these potentially toxic organic pollutants in soils and sediments is most studied environmental compartments. In recent past, studies were carried out on PAHs, OCPs and PCs in various soils and sediments in India. But, this is the first study on these pollutants in soils and sediments from an urbanized river flood plain area in Delhi, India. During 2018, a total of fifty-four samples including twenty-seven each of soil and sediment were collected and analyzed for thirteen priority PAHs, four OCPs and six PCs. The detected concentration of ∑PAHs, ∑OCPs and ∑PCs in soils ranged between 473 and 1132, 13 and 41, and 639 and 2112 µg/kg, respectively, while their concentrations in sediments ranged between 1685 and 4010, 4.2 and 47, and 553 and 20,983 µg/kg, respectively. PAHs with 4-aromatic rings were the dominant compounds, accounting for 51 and 76% of total PAHs in soils and sediments, respectively. The contribution of seven carcinogen PAHs (7CPAHs) in soils and sediments accounted for 43% and 61%, respectively, to ∑PAHs. Among OCPs, p, p’-DDT was the dominant compound in soils, while α-HCH was found to be dominated in sediments. The concentrations of ∑CPs (chlorophenols) were dominated over ∑NPs (nitrophenols) in both the matrices. Various diagnostic tools were applied for the identification of their possible sources in soil and sediments. The observed concentrations of PAHs, OCPs and PCs were more or less comparable with the recently reports from various locations around the world including India. Soil quality guidelines and consensus-based sediment quality guidelines were applied for the assessment of ecotoxicological health effect.

     

Total Volatile Organic Compounds in the Urban Environment of Delhi

ABSTRACT

Total volatile organic compounds (TVOCs) in the urban ambient environment of Delhi were monitored from November 1994 to June 1995 at 13 sites using an inexpensive and a manual-labor-intensive sample collection procedure in want of sophisticated equipment. The results of the study show appreciable levels of TVOCs in the ambient environment of Delhi. The amount of TVOCs in the ambient environment was found to vary between 3 and 42 ppmv and exhibited wide temporal and seasonal variations. On a diurnal cycle, TVOC levels mostly peaked at 9:00 a.m., which coincided with the peak traffic hour. TVOC buildup in the urban atmosphere has serious implications for air quality through the formation of highly toxic oxidants. The results of this preliminary study make out a strong case for a regular monitoring of TVOCs in the urban environment of Delhi.     

An insight into the influence of low dose irradiation pretreatment on the microbial decolouration and degradation of Reactive Red-120 dye

The influence of low dose irradiation pretreatment on the microbial decolouration and degradation of Reactive Red-120 (RR-120) dye was investigated in detail by using Pseudomonas sp. SUK1. About 27%, 56% and 66% decolouration of 150 ppm RR-120 dye solution was observed by applying 0, 0.5 and 1 kGy doses, respectively, in the first step followed by microbial treatment for 24 h under static condition. Similarly, about 70%, 88% and 90% TOC removal was observed by applying 0, 0.5 and 1 kGy doses, respectively, in the first step followed by the microbial treatment for 96 h under static condition. The radiation induced fragmented products of RR-120 at doses of 0.5 and 1 kGy were investigated by FTIR and electrospray ionization-MS analysis. The induction of the enzymes viz. laccase, tyrosinase, azoreductase and NADH-2,6-dichlorophenol indophenol reductase was studied in the decolourised solution obtained after irradiating 150 ppm RR-120 dye solution with 0 and 1 kGy doses followed by the microbial treatment for 96 h under static condition. The enzymatic degradation products were studied by FTIR, HPLC and GC–MS. The toxicity study of the treated dye solution on plants revealed the degradation of RR-120 into non-toxic products by combined radiation-microbial treatment. This study explores a reliable and promising way to use industrially viable dose (?1 kGy) and microbial strain viz. Pseudomonas sp. SUK1 for permissible safe disposal of dye solutions from textile industries.