Lakshmi Narayana Suvarapu

Review on Analytical and Biological Applications of Hydrazones and their Metal Complexes

Hydrazones are very important group of analytical regents for the determination of various metal ions by using various analytical techniques. Besides this use of hydrazones are also having biological activities also. In this paper we first discussed about the chemical nature of hydrazones and their biological activities. We mainly focused on the papers which were published during 1980-2011 on analytical applications (spectrophotometric and spectrofluorimetric) of hydrazones. We gave the total established conditions for the determination of various metal ions with hydrazones.

Recent Developments in the Speciation and Determination of Mercury Using Various Analytical Techniques.

This paper reviews the speciation and determination of mercury by various analytical techniques such as atomic absorption spectrometry, voltammetry, inductively coupled plasma techniques, spectrophotometry, spectrofluorometry, high performance liquid chromatography, and gas chromatography. Approximately 126 research papers on the speciation and determination of mercury by various analytical techniques published in international journals since 2013 are reviewed.

Determination of heavy metals in the ambient atmosphere: A review

Heavy metal determination in ambient air is an important task for environmental researchers because of their toxicity to human beings. Some heavy metals (hexavalent chromium (Cr), arsenic (As), cadmium (Cd) and nickel (Ni)) have been listed as carcinogens. Furthermore, heavy metals in the atmosphere can accumulate in various plants and animals and enter humans through the food chain. This article reviews the determination of heavy metals in the atmosphere in different areas of the world since 2006. The results showed that most researchers concentrated on toxic metals, such as Cr, Cd, Ni, As and lead. A few studies used plant materials as bio-monitors for the atmospheric levels of heavy metals. Some researchers found higher concentrations of heavy metals surrounding industrial areas compared with residential and/or commercial areas. Most studies reported the major sources of the particulate matter and heavy metals in the atmosphere to be industrial emissions, vehicular emissions and secondary aerosols.

Speciation and determination of mercury by various analytical techniques

Abstract Mercury is one of the most important metals to environmental researchers due to its toxicity. In recent years, many authors determined the concentration of mercury and its different forms in the environment, such as soil, water, atmosphere and biota, with various analytical techniques, such as atomic absorption spectrometry, spectrophotometry, voltammetry, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry, spectrofluorometry and chromatography. The objective of this paper is to summarize the recent understanding of the available techniques for the analysis and speciation of mercury in environmental and biological samples reported worldwide during 2010–2011. We tabulated all the analytical parameters of about 129 research papers published in reputable international journals during 2010–2011 about mercury determination and speciation studies.

Occurrence and Concentrations of Toxic VOCs in the Ambient Air of Gumi, an Electronics-Industrial City in Korea

This study was carried out to characterize the occurrence and concentrations of a variety of volatile organic compounds (VOCs) including aliphatic, aromatic, halogenated, nitrogenous, and carbonyl compounds, in the ambient air of Gumi City, where a large number of electronics industries are found. Two field monitoring campaigns were conducted for a one year period in 2003/2004 and 2010/2011 at several sampling sites in the city, representing industrial, residential and commercial areas. More than 80 individual compounds were determined in this study, and important compounds were then identified according to their abundance, ubiquity and toxicity. The monitoring data revealed toluene, trichloroethylene and acetaldehyde to be the most significant air toxics in the city, and their major sources were mainly industrial activities. On the other hand, there was no clear evidence of an industrial impact on the concentrations of benzene and formaldehyde in the ambient air of the city. Overall, seasonal variations were not as distinct as locational variations in the VOCs concentrations, whereas the within-day variations showed a typical pattern of urban air pollution, i.e., increase in the morning, decrease in the afternoon, and an increase again in the evening. Considerable decreases in the concentrations of VOCs from 2003 to 2011 were observed. The reductions in the ambient concentrations were confirmed further by the Korean PRTR data in industrial emissions within the city. Significant decreases in the concentrations of benzene and acetaldehyde were also noted, whereas formaldehyde appeared to be almost constant between the both campaigns. The decreased trends in the ambient levels were attributed not only to the stricter regulations for VOCs in Korea, but also to the voluntary agreement of major companies to reduce the use of organic solvents. In addition, a site planning project for an eco-friendly industrial complex is believed to play a contributory role in improving the air quality of the city.

Characterization of Odorous Compounds (VOC and Carbonyl Compounds) in the Ambient Air of Yeosu and Gwangyang, Large Industrial Areas of South Korea

Odorous compounds play an important role in air pollution in industrial areas and the residential areas surrounding them. This study measured the odorous volatile organic compounds (VOC) and carbonyl compounds at Yeosu and Gwangyang, two large industrial areas of South Korea, during four seasons of 2008-2009. Along with these two cities, the same odorous compounds were measured at Suncheon, which was selected as a control site. The concentrations of VOC and carbonyl compounds that were listed as odorous air pollutants by the Ministry of Environment of South Korea are discussed. Benzene and formaldehyde were included in the target analytes because of their carcinogenic nature. Most researchers only examined the concentration of odorous compounds in ambient air but the present study evaluated the odor intensity, which is a new parameter that will help better understand the precise odor perceived by people. This paper describes the seasonal variations and spatial distribution of the above-mentioned odorous compounds at the specified sites. Pearson correlation coefficients between the odorous compounds and other air pollutants, such as ozone, CO, SO2, NO2, and PM10, and meteorological conditions, such as temperature and wind speed, provide the source information of odorous VOC and carbonyl compounds.

Review on the Concentrations of Benzo[a]pyrene in the Indian Environment Since 1983

ABSTRACT The concentrations of benzo[a]pyrene [B(a)P] in the Indian environment since 1983 are reviewed. For this purpose, nearly sixty research papers on the determination of B(a)P in the Indian environment published in International journals were evaluated. The literature survey showed that the most of the research on determining the B(a)P levels in the Indian environment had been published in recent years. This review tabulated all the analytical parameters, such as extraction method, analyzed equipment, sampling medium, and detection limit in determination of B(a)P in the environment. This study also compares the concentration of B(a)P reported in the Indian environment with other Asian and Western countries. This review predicts that the concentrations of B(a)P reported in the ambient air of India were much higher than the Western countries, such as Germany, Italy, Greece, USA, and UK. On the other hand in Asian countries, the concentrations of B(a)P were reported in India were higher than the countries, such as Japan, Korea, Hong Kong, and Taiwan but comparable with China.

Recent Studies on the Speciation and Determination of Mercury in Different Environmental Matrices Using Various Analytical Techniques

This paper reviews the current research on the speciation and determination of mercury by various analytical techniques, including the atomic absorption spectrometry (AAS), voltammetry, inductively coupled plasma optical emission spectrometry (ICP-OES), ICP-mass spectrometry (MS), atomic fluorescence spectrometry (AFS), spectrophotometry, spectrofluorometry, and high performance liquid chromatography (HPLC). Approximately 96 research papers on the speciation and determination of mercury by various analytical instruments published in international journals since 2015 were reviewed. All analytical parameters, including the limits of detection, linearity range, quality assurance and control, applicability, and interfering ions, evaluated in the reviewed articles were tabulated. In this review, we found a lack of information in speciation studies of mercury in recent years. Another important conclusion from this review was that there were few studies regarding the concentration of mercury in the atmosphere.