Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.

Water pollution is one of the global challenges that society must address in the 21st century aiming to improve water quality and reduce human and ecosystem health impacts. Industrialization, climate change, and expansion of urban areas produce a variety of water pollutants. In this work, we discuss some of the most recent and relevant findings related to the release of heavy metals, the possible risks for the environment and human health, the materials and technologies available for their removal. Anthropogenic activities are identified as the main source of the increasing amounts of heavy metals found in aquatic environments. Some of the health hazards derived from repeated exposure to traces of heavy metals, including lead, cadmium, mercury, and arsenic, are outlined. We also give some perspectives about several techniques used to detect heavy metals, as well as about the factors that could affect the contaminant removal. The advantages and drawbacks of conventional and non-conventional heavy metal removal methods are critically discussed, given particular attention to those related to adsorption, nanostructured materials and plant-mediated remediation. Some of the commercial products currently used to eliminate heavy metals from water are also listed. Finally, we point out some the requirements and opportunities linked to developing efficient methods for heavy metal removal, such as the ones that exploit nanotechnologies.

Heavy metal water pollution: A fresh look about hazards, novel and conventional remediation methods

Milk in its natural form has a high food value, since it is comprised of a wide variety of nutrients which are essential for proper growth and maintenance of the human body. In recent decades, there has been an upsurge in milk consumption worldwide, especially in developing countries, and it is now forming a significant part of the diet for a high proportion of the global population. As a result of the increased demand, in addition to the growth in competition in the dairy market and the increasing complexity of the supply chain, some unscrupulous producers are indulging in milk fraud. This malpractice has become a common problem in the developing countries, which lack strict vigilance by food safety authorities. Milk is often subjected to fraud (by means of adulteration) for financial gain, but it can also be adulterated due to ill-informed attempts to improve hygiene conditions. Water is the most common adulterant used, which decreases the nutritional value of milk. If the water is contaminated, for example, with chemicals or pathogens, this poses a serious health risk for consumers. To the diluted milk, inferior cheaper materials may be added such as reconstituted milk powder, urea, and cane sugar, even more hazardous chemicals including melamine, formalin, caustic soda, and detergents. These additions have the potential to cause serious health-related problems. This review aims to investigate the impacts of milk fraud on nutrition and food safety, and it points out the potential adverse human health effects associated with the consumption of adulterated milk.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1541-4337.12181

Impacts of Milk Fraud on Food Safety and Nutrition with Special Emphasis on Developing Countries

In this work, the occurrence of contaminants in drinking water sources was described in relation to their treatment options based on both conventional (e.g., coagulation-flocculation, sedimentation...

Occurrence of contaminants in drinking water sources and the potential of biochar for water quality improvement:A review

The potential of Lemna gibba L. and Lemna minor L. to remove Cu, Pb, Zn, and As in gallery water in a mining area in Keban, Turkey

Water resources in the world have been profoundly influenced over the last years by human activities, whereby the world is currently facing critical water supply and drinking water quality problems. In many parts of the world heavy metal (HM) concentrations in drinking water are higher than some international guideline values. Discussing about the HM pollution in drinking water, the incorporation of them into the food chain, and their implications as a global risk for the human health, are the objectives of this review. It is known that there are million people with chronic HM poisoning which has become a worldwide public health issue, while 1.6 million children die each year from diseases for which contaminated drinking water is a leading cause. There is also evidence of HM in drinking water that are responsible for causing adverse effect on human health through food chain contamination. A global effort to offering affordable and healthy drinking water most to be launched throughout the world, while various laws and regulations to protect and improve the utilization of drinking water resources should be updated or created throughout the world, including the low income countries; otherwise, the problem of HM-polluted drinking water will be growing because demand for drinking water is still growing such as this problem will become even more pressing in the future. Finally, notwithstanding, additional researches are necessaries about the correlation between HM concentration in drinking water and human diseases, while the development of robust, cheap and sustainable technologies to improve the drinking water quality is necessary.

	 

	Key words: Groundwater, aquifer, water quality, water pollution, microorganism, water supply, microbial communities, food chain, disease

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Heavy metal pollution in drinking water - a global risk for human health: A review

The ability of various crops to grow and maintain its average yield when they are cultivated in contaminated soils should be better explored to choose the most appropriate crop when suddenly a gasoline-pipeline collapse on soils of subsistence agricultural systems. The aim of the present study was to evaluate the effect of organic or inorganic amendments on plant characteristics, biomass yield, colony-forming units (CFU), and on biological and chemical soil characteristics when it was cultivated, under greenhouse conditions, in a soil artificially polluted with gasoline and amended or not with sludge, compost, manure or inorganic fertilizers. Our results suggest that the electrolytic conductivity, organic matter, inorganic N, extractable P and exchangeable K were strongly influenced by the organic or inorganic amendments but not by the gasoline. Gasoline contamination reduced seedling emergence, shoot length, root volume, root dry weight, shoot dry weight and abundance of nodules but organic or inorganic amendments increased them. In addition, gasoline-polluted soil amended with sludge had the highest seedling emergence, shoot length, root volume, root dry weight and shoot dry weight. The soil used in this experiment contains autochthonous microorganisms able to grow in a gasoline-polluted soil while gasoline-spiked soil amended with manure or compost maintained their CFU and even increased using gasoline as a sole carbon source, suggesting that manure or compost contains indigenous microorganism that uses gasoline as a sole carbon source. Plant characteristics and yield were increased in the order of sludge > compost = manure > inorganic fertilizer > unamended and unpolluted soil > unamended polluted soil. Hence, a gasoline-spiked soil amended with sludge can be successfully cultivated with common vetch. 

	 

	Key words: Biomass yield, colony-forming unit, greenhouse conditions, indigenous microorganisms, organic or 

	inorganic amendments, plant characteristics.

Fern

Papers

Heavy metal pollution in drinking water - a global risk for human health: A review

Growth and development of common vetch ( Vicia sativa L.) in a gasoline-polluted soil amended with organic or inorganic amendments