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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.

The main purpose of this study is to investigate the bioaccumulation pattern and fate of heavy metals in duckweed‐based wastewater treatment ponds with different depth.

Three replicates of four reactors were used in this experiment. The reactors were randomly distributed on the bench and filled with 50 percent diluted sewage for the control reactors whereas diluted sewage mixed with 5 mg Pb/l and 5 mg Zn/l was used for the treatment reactors. The reactors were stocked with Lemna gibba at 1,000 g fresh weight per each square meter. The culture tanks were exposed to temperature range of 21‐25°C and light regime of 16 hours light using halogen lamps and 8 hours dark. The light intensity was maintained around 200 μ E m⁻² S⁻¹. The experiment extended for 30 days. Regular monitoring of the growth performance of duckweed was carried out with subsequent analysis of dry matter, heavy metals, phosphorous and nitrogen content. Composite samples from the water phase were subjected to the analysis of ammonia, nitrite, nitrate, orthophosphate and sulfate concentration. The analysis of sediment and biofilm were carried out at the end of the experiment. Interpretation of results was carried out using one‐way analysis of variance.

Statistical analysis showed a significant reduction in the growth rate of duckweed within the first five days exposure time. After five days exposure, the growth rate in the treatments returned to the normal growth till day 15 after which the growth became significantly lower in the small and medium scale ponds. The results revealed that zinc is more bio‐available than lead and both metals are mostly precipitated in the sediment probably as sulfides.

The results help in enhancement of heavy metals removal in a small anaerobic pretreatment unit before entering to the pond system by sulfate addition.

The results of the study confirm the positive effect of pond depth in reducing the heavy metal toxicity to the duckweed‐based wastewater treatment ponds.

The presence of heavy metals in milk causes many acute and chronic physiological dysfunctions in human organs. The present study aims to investigate the heavy metals in cow's and buffalo's milk of two major cities, Karachi and Gujranwala, Pakistan to estimate metal intake by humans from this source.

In total, 48 milk samples from 2 cities were drawn from animals' udder to avoid contamination. Each sample was digested with nitric acid at 105 ^oC (degree Celsius) on a pre-heated electric hot plate to investigate the metals by atomic absorption spectroscopy (flame type). Air-acetylene technique analyzed chromium, cadmium and lead, and the hydride method analyzed arsenic in the milk samples.

The results revealed the highest mean lead concentration (19.65 ± 43.86 ppb) in the milk samples, followed by chromium (2.10 ± 2.33 ppb) and arsenic (0.48 ± 0.73 ppb). Cadmium was not detected in any sample, assuming cadmium's occurrence was below the detection level. The concentrations of all the metals in the samples of the two cities do not differ statistically. Lead concentrations in the buffalo's milk were higher than in cow's milk (p < 0.05). However, the concentrations of arsenic and chromium between buffalo's and cow's milk do not differ statistically. The present study reveals a lower level of metals in the milk than those conducted elsewhere. The mean concentrations of all the metals met the World Health Organization's (WHO) safety guidelines (1993).

Although cadmium causes toxicity in the human body, cadmium could not be measured because cadmium's concentration was below the detection level, which is 1 ppb.

This study will help reduce the toxic metals in our environment, and the sources of heavy metals, particularly from the industrial sector could be identified. The feed and water consumed by the milking animals could be carefully used for feeding them.

This study will help reduce the diseases and malfunction of human organs and organ systems since these heavy metals cause toxicity and carcinogenicity in humans. Arsenic and chromium cause cancer while lead causes encephalopathy (a brain disease).

The study reports heavy metal concentrations in the two attributes of four independent variables of raw milk samples that were scarcely reported from Pakistan.

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.

The purpose of this paper is to compare environmental performance of two shackle insulator manufacturing enterprises in India by evaluating and quantifying the life cycle environmental impacts in these enterprises using ISO 14040 guidelines.

All relevant life cycle phases – raw material, manufacturing, transportation and disposal – are considered. Primary inventory data for the two enterprises are collected through observations of processes at the sites. Ecoinvent 3.0 database is used as secondary data source. Process flow models are developed using Umberto software. ReCiPe impact assessment methodology is adopted to calculate environmental impacts in terms of endpoint categories of ecosystem quality, human health and resource availability; and midpoint categories of climate change, fossil depletion, human toxicity, metal depletion, ozone depletion, terrestrial acidification and water depletion.

This study has found that manufacturing phase followed by raw material extraction and transportation phases are responsible for most of the environmental impacts. This study also found that raw materials used in glaze preparation (manganese and ferrite), electricity, heavy fuel oil (C-9) and cotton have high environmental impacts in the manufacturing phase.

The limitation of this study is that most of the inventory data are collected from only two manufacturing plants.

The researchers/enterprises can use the knowledge body for modelling and result comparison under different conditions. The enterprises can do the micro analysis of environmental effects of processes to improve environmental as well as economic performance. The government agencies can use the data for policy development and deployment.

The main contribution of the research is the creation of a knowledge body in the area of ceramic product environmental impacts. The paper provides inventory for the life cycle assessment (LCA) of shackle insulators using primary source (measured values) as no secondary data source is available for the shackle insulators. The inventory and results of this study can be used as reference for the future LCA studies in ceramic industry.

The purpose of this paper is to address the case of toxic metal contamination of Sepetiba Bay caused by the Ingá Company. The paper reviews the history of the contamination and discusses the current presence of metals in the bay sediments, demonstrating that the toxic metals are clearly enriched. Sepetiba Bay is prone to significant dredging activities that make metals available in the food chain, affecting human populations, mainly fishermen communities.

The study presents the case of the Ingá Company based on international literature and data provided by previous studies.

Through the analysis and compilation of diverse data from the literature, this study demonstrates that the Ingá Company is a major source of Cd, Pb and Zn due to its calamine processing activities used to obtain high purity Zn.

This study highlights important research to complete the historical scenario of heavy metal contamination of the Sepetiba Bay by Ingá Company. The results indicate that the contaminants from the Ingá Company can indeed be traced in the sediments of Sepetiba Bay. These data have the utmost value for the environmental management of this coastal system, because such high concentrations of toxic metals in marine sediments have serious implications for the environmental quality of the bay and may negatively affect biota and human health. Therefore, this study suggests that it is now necessary to monitor this region for contamination continuously.

Lead is a known reproductive toxicant in humans and animals. Data on cadmium reproductive effects in humans are inconclusive, and in female animals are lacking. More information on the toxicokinetics and toxicity of Pb and Cd during the reproductive period and in developing young is needed. Experimental studies on rats conducted in laboratories in Croatia and in the USA separately and as collaborative research show that Pb or Cd have effects on reproductive function. Chronic or subchronic oral Pb or Cd exposure of the dams causes decreased pup weight and survival, and depressed serum progesterone concentration in Cd‐exposed dams at the term. No paternally mediated Pb effects were found in offspring. Organ Pb or Cd accumulation was accompanied by changes in essential element concentrations in both dam and foetus. Acute in vivo and in vitro exposure to Cd had specific effects on gonadal steroidogenesis in both males and females. Proposes possible sites of action of Cd in the steroidogenic pathway.

The study aimed at developing the bioremediation model of Lapindo mud through multisymbiotic organism.

The research was conducted using completely randomized design. The model plants chosen in this research were soybean. The interaction pattern during the treatment was used to develop the bioremediation model based on the parameters.

The results showed that there was an effect of the type of organism on the parameters, namely: the growth of plant (biomass, height, length of root, and number of leaves), the biomass of root nodules, the percentage of mycorrhizal infection, the content of water, nitrogen, phosphorus, and total petroleum hydrocarbons (TPHs). There was a pattern of multisymbiotic interaction between each organism and roles of each symbiont in that interaction. Therefore, the plants were capable of surviving in the environment of Sidoarjo Lapindo mud. This pattern can be named as the bioremediation model proposed, which is the analogy of tripartite symbiosis between plants, mycorrhizae, and Rhizobium but also adding plant growth bacteria such as phosphate-solubilizing bacteria and hydrocarbon degradation bacteria. The implementation of this model can be used to treat oil-contaminated soil in order to be used as a plant growth medium.

Phytoremediation is a new and promising approach to remove contaminants in the environment but using plants alone for remediation confronts many limitations. Therefore, the application of plant-growth-promoting rhizobia (PGPR) has been extended to remediate contaminated soils in association with plants (Zhuang et al., 2007). The development of the model will use the analogy of tripartite symbiosis between plants, mycorrhizae, and Rhizobium. The developed model will be based on the interaction pattern on each parameters obtained. Bioremediation is chosen because it is considered an effective technique to transform toxic components into less toxic products without disrupting the surrounding environment. Besides, bioremediation is cheaper and environment-friendly because it utilizes microorganisms to clean pollutants from the environment (Nugroho, 2006).

This report, presented as the keynote paper at Surface Mount International, is the culmination of joint efforts to assess the use of lead in electronics assembly. The study, which is presented in two parts, involved the collaboration of the following participants: B. R. Allenby and J. P. Ciccarelli, AT&T, Basking Ridge, New Jersey; I. Artaki, J. R. Fisher and D. Schoenthaler, AT&T Bell Laboratories, ERC, Princeton, New Jersey; T. A. Carroll, Hughes, El Segundo, California; D. W. Dahringer, Y. Degani, R. S. Freund, T. E. Graedel, A. M. Lyons and J. T. Plewes, AT&T Bell Laboratories, Murray Hill, New Jersey; C. Gherman and H. Solomon, GE Aerospace, Philadelphia, Pennsylvania; C. Melton, Motorola Inc., Schaumburg, Illinois; G. C. Munie, AT&T Bell Laboratories, Indian Hill, Naperville, Illinois; and N. Socolowski, Alpha Metals, Jersey City, New Jersey. Part 1 was published in the previous issue of Circuit World, Vol. 19, No. 2.

Heavy metals play a crucial role in the economic development of any nation. Industries utilizing heavy metals, consequently, emanate a large volume of metal-containing liquid effluents. Since metals are non-renewable and finite resources, their judicious and sustainable use is the key. Hazardous metal-laden water poses threat to human health and ecology. Apart from metals, these industrial effluents also consist of toxic chemicals. Conventional physical–chemical techniques are not efficient enough as it consumes energy and are, therefore, not cost effective.

It is known that biomaterials namely microorganisms, plants, and agricultural biomass have the competence to bind metals, in some cases, selectively, from aqueous medium. This phenomenon is termed as “metal biosorption.” Biosorption has immense potential of becoming an effective alternative over conventional methods. The authors in the present chapter have used secondary data from their previous research work and attempted to develop few strategic models through their feasibility studies for metal sustainability.