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Impact of heavy metal (HM) pollution and its understanding on environment as well as human beings has grown a lot during the last few decades. The goal of this study is to create a scientometric study on heavy metal contamination, in the period 1989 to 2020, in order to provide futuristic goals for the new researchers on wastewater treatment. For this, a search was conducted in the Web of Science (WoS) and Scopus databases, related to heavy metal pollution. Totally, 37,154 records were collected during the study period from 1989 to 2020. The findings revealed that China, the United States, and India has most referenced papers across a wide range of trans disciplinary issues such as toxicity, technology, and pollution. As a result, this study concludes that more research on various treatment methods is required in order to obtain high-quality water for consumption and routine activities, with the incorporation of various treatment tasks poses various challenges for the upcoming future studies. [Display omitted] • A bibliometric study is performed an heavy metal pollution between 1989 and 2020. • 37,154 records were critically analyzed to extract the bibliographic maps. • China, USA and India are the leading countries in heavy metal pollution research. • Advanced oxidation, coagulation-flocculation, adsorption, and membrane filtering technologies were focussed. [ABSTRACT FROM AUTHOR]

Our paper provides a comparative perspective on the development of public primary education in four of the largest developing economies circa 1910: Brazil, Russia, India and China (BRIC). These four countries encompassed more than 50% of the world's population in 1910, but remarkably few of their citizens attended any school by the early 20th century. We present new, comparable data on school inputs and outputs for BRIC drawn from contemporary surveys and government documents. Recent studies emphasize the importance of political decentralization, and relatively broad political voice for the early spread of public primary education in developed economies. We identify the former and the lack of the latter to be important in the context of BRIC, but we also outline how other factors such as factor endowments, colonialism, serfdom, and, especially, the characteristics of the political and economic elite help explain the low achievement levels of these four countries and the incredible amount of heterogeneity within each of them. [ABSTRACT FROM AUTHOR]

Abstract: In 2006 a report on the analysis for lead in 80 new residential paints from four countries in Asia revealed high levels in three of the countries (China, India and Malaysia) and low levels in a fourth country (Singapore) where a lead in paint regulation was enforced. The authors warned of the possible export of lead-painted consumer products to the United States and other countries and the dangers the lead paint represented to children in the countries where it was available for purchase. The need for a worldwide ban on the use of lead in paints was emphasized to prevent an increase in exposure and disease from this very preventable environmental source. Since the earlier paper almost 300 additional new paint samples have been collected from the four initial countries plus 8 additional countries, three from Asia, three from Africa and two from South America. During the intervening time period two million toys and other items imported into the United States were recalled because the lead content exceeded the United States standard. High lead paints were detected in all 12 countries. The average lead concentration by country ranged from 6988 (Singapore) to 31,960ppm (Ecuador). One multinational company sold high lead paint in one country through January 2007 but sold low lead paint later in 2007 indicating that a major change to cease adding lead to their paints had occurred. However, the finding that almost one-third of the samples would meet the new United States standard for new paint of 90ppm, suggests that the technology is already available in at least 11 of the 12 countries to produce low lead enamel paints for domestic use. The need remains urgent to establish effective worldwide controls to prevent the needless poisoning of millions of children from this preventable exposure. [Copyright &y& Elsevier]