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This paper aims to investigate the contents of heavy metals Cd, Cr, Ni, Cu, Pb and Zn in the soil of vegetable production bases in the Yongnian County of Hebei Province by random sampling.

The environmental quality conditions of these heavy metals were evaluated by both the single quality index and comprehensive quality index methods.

It was concluded that the average heavy metal contents in the soil of protected vegetable fields in the Yongnian County are all under the limit values prescribed by the environmental quality evaluation standard for farmland of greenhouse vegetables production (2007), so the soil’s environmental quality is classified as first class regarding cleanliness. It is fit for the plantation of non-polluted vegetables. It is shown that there is a cumulative trend of heavy metal contents in the soil with age after analysis of a correlation coefficient between heavy metal contents and age in Yongnian’s protected fields and excessive application of fertilizers or organic fertilizers, which is the main factor leading to an increase in heavy metal contents in the soil.

It is suggested that the amount of fertilizer should be properly reduced to prevent the soil’s environmental deterioration, the vegetable planting structure should be improved and the vegetables grown in areas with weaker accumulation of heavy metals should be cultivated.

This study aims to examine the metal pollution in coastal sediment in the Peninsular Malaysia.

Approximately 141 published studies were screened from 1,285 documents and reviewed to determine the existing pollution status in the coastal areas of Peninsular Malaysia and the metals under review were Pb, Hg, Cd, Ar, Cu, Zn, Cr and Ni. Sources of pollutants and their effect on biological systems, marine organisms and human health were addressed in this review as well as recommendation of heavy metal removal or remedies in short. Emphasis is placed on marine pollution, particularly on the toxic metal accumulation in biota.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.

Malaysians are the highest seafood consumers in the region; be it fresh or processed. Environmental pollution has put the safety of seafood at stake, heavy metals among others. This study was done to assess the health risk associated with selected heavy metals ingestion from processed seafood.

The most preferred processed seafood type and the intake rates were determined from a cross-sectional survey among communities in Shah Alam, Selangor (n = 90). The processed seafood were then purchased from local traders (n = 81), underwent homogenization, acid digestion (0.5 g) in Multiwave 3,000 and heavy metal quantitation (Hg, Pb, Cd, As) using ICP-MS. Estimated weekly ingestion (EWI), hazard quotient (HQ), hazard index (HI), lifetime cancer risk (LCR), and target risk (TR) were used to estimate the risk associated with processed seafood consumption.

Arsenic was the highest metal detected, acetes topping the list (10.05 ± 0.02 mg/kg). Mercury was detected at significantly higher level in salted fourfinger threadfin (0.88 ± 0.09 mg/kg) while Pb and Cd in toli shad (2.67 ± 0.16 mg/kg; 0.32 ± 0.22 mg/kg). Non-cancer risk was estimated for consumption of dried/salted food types with hazard index (HI) anchoives (5.2) > salted fourfinger threadfin (1.8) > toli shad (1.7). Besides, an unacceptable cancer risk was estimated for all food types for continuous consumption (Total risk (TR) > 10–4), except the dried acetes.

This study implies that although the concentration of most heavy metals were well below the permitted value, significant amount of risk present for consumption of several species. In addition, for selected heavy metals such as Hg and As, speciation analysis followed by risk assessment would provide a clearer picture.

There is a need to refer back to the local permissible level of heavy metals in processed seafood and formulate safe consumption guide.

The food types are advised to be consumed with caution especially by the sensitive group.

This study estimated the risk of cancer and other non-cancer disease from processed seafood consumption among Malaysian women.

Investigates the fate and toxicity of continuous feeding with increasing dosage of heavy metal ions – Cu, Pb, Zn, Cr(VI) – on biogas production from anaerobic digestion of sewage sludge. The efficiency of the system (as measured by biogas production and volatile organic matter removal rate) was reduced for about 35 days before returning to a steady state with the toxicity ranking Cu > Cr (VI) > Pb >Zn. Also looks at the effect of two “pulse” doses of the metals.

THIS paper shows briefly the origins and development of a comparatively new and certainly important branch of engineering science. For many years the alloys of the light metals, particularly of aluminium and magnesium, have been developed, until the term “light alloys” has come to be generally accepted as indicating the alloys of the light metals or any metallic alloy having a density of less than about 3·8. Towards the other end of the density scale are now being developed alloys of the heavy metals, mainly tungsten and tantalum. The techniques of production and manufacture of these two groups are very different: whereas the light alloys are produced and manipulated mainly by melting, casting, annealing, and forging, the heavy alloys are produced by various processes of powder metallurgy, resulting in substances with densities of 15 or more.

This paper aims to investigation of processes for Pb²⁺ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb²⁺ ions by various nanocomposites has been explained from water/wastewaters. ZnO-based nanocomposites, as eco-friendly nanoparticles with unique physicochemical properties, have received increased attention to remove Pb²⁺ ions from water/wastewaters.

In this review, different ZnO-based nanocomposites were reviewed for their application in the removal of Pb²⁺ ions from the aqueous solution, typically for wastewater treatment using methodology, such as adsorption. This review focused on the ZnO-based nanocomposites for removing Pb²⁺ ions from water and wastewaters systems.

The ZnO-based nanocomposite was prepared by different methods, such as electrospinning, hydrothermal/alkali hydrothermal, direct precipitation and polymerization. Depending on the preparation method, various types of ZnO-based nanocomposites like ZnO-metal (Cu/ZnO, ZnO/ZnS, ZnO/Fe), ZnO-nonmetal (PVA/ZnO, Talc/ZnO) and ZnO-metal/nonmetal (ZnO/Na-Y zeolite) were obtained with different morphologies. The effects of operational parameters and adsorption mechanisms were discussed in the review.

The findings may be greatly useful in the application of the ZnO-based nanocomposite in the fields of organic and inorganic pollutants adsorption.

The present study is novel, because it investigated the morphological and structural properties of the synthesized ZnO-based nanocomposite using different methods and studied the capability of green-synthesized ZnO-based nanocomposite to remove Pb²⁺ ions as water contaminants.

The current review can be used for the development of environmental pollution control measures.

This paper reviews the rapidly developing field of nanocomposite technology.

Bismuth is relatively little known in general; however, it has been known since the fifteenth century in Germany and was called by Paracelsus “Bismutum”. With very similar properties to lead, it could be called the “twin brother of lead”, but bismuth is considered non‐toxic and used in cosmetics and pharmaceuticals. It is really a unique metal, considered as a metal within the periodic table of elements, but has more similarity to semimetals than to metals. Bismuth replaces the formerly and widely used lead in EP‐greases and EP‐lubricants giving better properties to them, even using down to half of the metal concentration. Bismuth has very high synergism to sulphur, the oldest known element. So, the combination of the oldest known element sulphur with the newest “green and ecologically clean” metal Bismuth – is actually the modern and metallic extreme pressure technology – that follows the formerly used, during many decades, sulphur‐lead‐technology – but being non‐toxic.

The general behaviour of titanium and zirconium in pure chemical environments is summarised, and also the effects of common contaminants such as air and heavy metal ions that are present in many process streams. The beneficial effect of traces of soluble iron and copper and organic compounds in non‐oxidising acids is discussed and the relative effect of these upon the behaviour of titanium and zirconium pointed out. Information is provided upon the performance of titanium—0.15% palladium alloy under similar circumstances. The conclusion suggests that the behaviour of titanium and zirconium in various types of chemical plant is best determined by reference to in‐plant trials than by laboratory testing; the use of in‐plant corrosion probes is recommended.

This paper aims to select a type of mordant from aluminium salts, namely, aluminium sulphate, aluminium nitrate and polyaluminium chloride (PAC) with the lowest potential for contamination so that their use will minimise pollution from natural dye waste. It also aims to determine the pollution value of natural dye immersion waste from jackfruit wood extract, secang wood, mangsi fruit and several synthetic dyes, to identify potential environmental pollution.

Dyeing with natural dyes was performed by exhaust at room temperature by the pre-mordant method, while with synthetic dyes it was performed by exhaust according to the dyeing procedure (reactive, vat and naphthol). The groundwater, mordant solutions, natural dye extract and the waste-water from the natural and synthetic dyes were then tested to determine their biological oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids (TSS), pH, Al and heavy metal contents such as chromium (Cr), copper (Cu), cadmium (Cd), nickel (Ni), cobalt (Co) and lead (Pb).

Aluminium sulphate had the lowest pollution load while PAC had the highest, as aluminium sulphate had a higher BOD₅/COD ratio (0.62–0.67) than aluminium nitrate (0.56–0.64) or PAC (0.44–0.54). The dyeing waste from the three natural dyes contained an acidic pH of 3.5–4.2, Al of 75.280–621.34 mg/L, Cr of 0.154–0.215 mg/L and Cu of 0.035–0.072 mg/L. The values of TSS, COD and BOD₅ are higher than the quality standards of the waste but are environmentally friendly because the ratio of the BOD₅/COD values from the waste ranges from 0.44–0.67.

The findings indicate that as a mordant, aluminium sulphate results in lower pollution loads than aluminium nitrate and PAC. However, all three mordants contain Cr and Cu, albeit in negligible concentrations. Therefore, it is recommended that future studies strive to identify a mordant that has lower pollution loads and does not contain metals but can increase dyeing results to satisfy consumer requirements. It is the hope that, with the discovery of a new mordant, natural dyes will be the solution for the heavy metal pollution caused by synthetic dyes.

The use of environmentally-friendly mordants and natural dyes in the Indonesian textile and batik industry will give rise to superior quality eco-textile and eco-batik products. Such environmentally-friendly and high-quality products will not only increase competition and consumer interest but increase product sales as well which will, in turn, increase incomes and the economy. Additionally, an increase in the use of natural dyes by the textile and batik industry will serve as additional income to the communities and farmers from which the raw materials for the natural dyes are sourced thereby creating jobs and increasing welfare.

As environmentally-friendly mordants and natural dyes replace the hazardous and toxic materials currently used in the textile and batik industry, it guarantees the health and safety of its consumers and workers. Furthermore, as the waste-water produced is biodegradable, it reduces river and groundwater pollution. It is, therefore, expected that this information will not only lead to a shift in attitude within the textile and batik industries but the adoption of environmentally-friendly materials, for the sake of the environment, as well as the development of eco-textile and eco-batik products.

Aluminium sulphate is a mordant type of aluminium salt with a lower potential for contamination than aluminium nitrate and PAC. However, PAC has been discovered to be a mordant for natural dyes, as has the fruit of the mangsi shrub, which has recently been discovered as a naturally occurring blue dye.

The purpose of this study is to monitor suspended particulate matter (SPM), PM2.5 and source apportionment study for the identification of possible sources during the year 2018–2019 at Raipur, India.

Source apportionment study was performed using a multivariate receptor model, positive matrix factorization (PMFv5.0) with a view to identify the various possible sources of particulate matter in the area. Back-trajectory analysis was also performed using NOAA-HYSPLIT model to understand the origin and trans-boundary movement of air mass over the sampling location.

Daily average SPM and PM2.5 aerosols mass concentration was found to be 377.19 ± 157.24 µg/m³ and 126.39 ± 37.77 µg/m³ respectively. SPM and PM2.5 mass concentrations showed distinct seasonal cycle; SPM – (Winter ; 377.19 ±157.25 µg/m?) > (Summer; 283.57 ±93.18 µg/m?) > (Monsoon; 33.20 ±16.32 µg/m?) and PM2.5 – (Winter; 126.39±37.77 µg/m³) > (Summer; 75.92±12.28 µg/m³). Source apportionment model (PMF) have been applied and identified five major sources contributing the pollution; steel production and industry (68%), vehicular and re-suspended road dust (10.1%), heavy oil combustion (10.1%), tire wear and brake wear/abrasion (8%) and crustal/Earth crust (3.7%). Industrial activities have been identified as major contributing factor for air quality degradation in the region.

Chemical characterization of aerosols and identification of possible sources will be helpful in abatement of pollution and framing mitigating strategies. It will also help in standardization of global climate model.

The findings provide valuable results to be considered for controlling air pollution in the region.