Phytoremediation of Wastewater Containing Lead (Pb) in Pilot Reed Bed Using Scirpus Grossus

Phytoremediation is a technology to clean the environment from heavy metals contamination. The objectives of this study are to threat Pb contaminated wastewater by using phytoremediation technology and to determine if the plant can be mention as hyperaccumulator. Fifty plants of Scirpus grossus were grown in sand medium and 600 L spiked water in various Pb concentration (10, 30 and 50 mg/L) was exposed. The experiment was conducted with single exposure method, sampling time on day-1, day-14, day-28, day-42, day-70, and day-98. The analysis of Pb concentration in water, sand medium and inside the plant tissue was conducted by ICP-OES. Water samples were filtered and Pb concentration were directly analyzed, Pb in sand samples were extracted by EDTA method before analyzed, and Pb in plant tissues were extracted by wet digestion method and analyzed. The results showed that on day-28, Pb concentration in water decreased 100%, 99.9%, 99.7%, and the highest Pb uptake by plant were 1343, 4909, 3236 mg/kg for the treatment of 10, 30, and 50 mg/L respectively. The highest BC and TF were 485,261 on day-42 and 2.5295 on day-70 of treatment 30 mg/L, it can be mentioned that Scirpus grossus is a hyperaccumulator.     

On the kinetics of lead in the human body

Summary A compartment model is derived for the kinetics of lead in the human body. The parameters are estimated from field data. Numerical solutions of the equations are obtained. They are used to discuss recent theories on lead intake, in particular from the atmosphere.     

Highly Efficient Perovskite Solar Cell Photocharging of Lithium Ion Battery Using DC–DC Booster

Solar cells become a viable energy source to charge lithium ion batteries. Here a simple and efficient photocharging design approach is demonstrated, where a promising low cost single junction solar cell such as perovskite solar cell or dye sensitized solar cell efficiently charges a Li₄Ti₅O₁₂‐LiCoO₂ Li‐ion cell using a DC–DC voltage boost converter. The converter boosts the low input voltage of a single junction solar cell to charge a lithium ion cell and offers advantages including maximum power point tracking of solar photovoltaics and overvoltage protection for the lithium ion cell. This is the first demonstration of this technology. This approach leads to the highest reported overall efficiency of 9.36% and average storage efficiency of 77.2% at 0.5 C discharge for a perovskite solar cell‐converter charging. The high efficiency for the perovskite solar cell‐converter charging is attributed to maximum power harvesting along with high power conversion efficiency of the perovskite solar cell and low potential polarization between the charge and discharge voltage plateaus for the Li₄Ti₅O₁₂‐LiCoO₂ Li‐ion cell.     

Removal of soluble Cu and Pb by the automatic drip coffee brewing process: Application to risk assessment

Three commercial brands of coffee were examined for sorption of Cu and Pb. We kept experimental conditions close to those in ordinary situations by using an automatic drip coffee maker. One‐liter increments of de‐ionized water spiked with increasing amounts of Cu and Pb were used to make pots of coffee. Influent (water) metal concentration was then compared with effluent (coffee) metal concentration. We kept influent metal concentrations in ranges that might be expected due to contamination from storage tanks and pipes in municipal water delivery systems (0.1 to 5.0 mg/L). The coffee brewing process removed 78 to 90% of both Cu and Pb from influent water. We ran experiments by varying coffee strength (function of bed depth) and varying brewed coffee volume (function of bed depth and water volume) . Most of the metal that goes through the coffee bed does so in the early stages of the brewing process before the coffee bed is wetted. The main factor influencing removal of soluble metal by coffee is contact time with the wetted coffee bed. Therefore, the strength and/or volume of coffee brewed play a critical role in metal removal. Preliminary work with steeping teabags in metal spiked water showed little to no reduction in the soluble Cu and Pb concentration. Results of this study are important for risk assessment model formulations. Daily human exposure to Cu and Pb from municipal water systems may be grossly overestimated if a large proportion of tapwater ingestion by an individual is filtered through coffee.     

HEAVY METALS AND MARINE PHYTOPLANKTON: CORRELATION OF TOXICITY AND SULFHYDRYL-BINDING1,2

In a study of sublethal effects of metals on growth of the marine diatom Asterionella japonica Cleve, the relative toxicities of Hg, Cu, Zn, Pb, Cd, and Mn are shown to be correlated (r = 0.961) with the solubility products of the corresponding metal sulfides. The results, together with findings elsewhere, suggest a common action for these heavy metals, with toxicity deriving from metal binding to sulfhydryl-containing compounds in the cell.     

Lead Poisoning: Using Transdisciplinary Approaches to Solve an Ancient Problem

Conservation medicine examines the linkages among the health of people, animals, and the environment. Few issues illustrate this approach better than an examination of lead (Pb) toxicity. Lead is cheap and there is a long tradition of its use. But the toxic effects of Pb have also been recognized for many years. As a result, western societies have eliminated or greatly reduced many traditional uses of Pb, including many paints, gasoline, and solders because of threats to the health of humans and the environment. Legislation in several countries has eliminated the use of lead shot for hunting waterfowl. Despite these advances, a great many Pb products continue to be readily available. For example, wildlife agencies recognize that angling and shooting sports deposit thousands of tons of Pb into the environment each year. In recent years, our knowledge of the lethal and sublethal effects of Pb has grown dramatically. This discussion reviews the effects of lead on wildlife, humans, and domestic animals. It also discusses the importance of bringing together all interest groups to find safe alternatives, to develop new educational and policy initiatives, to eliminate many current uses of Pb, and to clean up existing problems.     

Lead Tetraacetate-Thiocarbohydrazide-Silver Proteinate Method for Light Microscopy of Polysaccharides

Lead tetraacetate-thiocarbohydrazide-silver proteinate reaction sequence for light microscopy of polysaccharides was evaluated on Carnoy's fixed rat liver sections. The results of this evaluation suggest that, on the light microscopic level, the lead tetraacetate-thiocarbohydrazide-silver proteinate method may serve as a practical and histochemically specific alternative to the lead tetraacetate-Schiff reaction for the localization of tissue carbohydrates.     

Assay for erythrocyte superoxide dismutase activity in patients with lung cancer and effects on pollution and smoke trace elements

The antioxidative effect of CuZnSOD, which catalyzes the dismutation of Superoxide anion (O₂-), provides a defense against the oxygen toxicity. The object of the study is to evaluate the erythrocytes Superoxide dismutase (SOD) activity in two groups of persons (Group I, healthy blood donors; Group II, lung cancer patients), using the spectrophotometric assay of NADH oxidation and the indirect method (2–27). The effect of trace elements, such as A1^3-, Cr³⁺, Fe³⁺, Hg²⁺, NI²⁺, and Pb²⁺ (producing free radicals oxygen and present in pollution and smoke) is also evaluated. The results show the decrease of SOD activity in lung cancer patients with respect to healthy individuals. Likewise, in those patients the enzymatic activity is bigger in early stage (I,II) with respect to advanced one (III) (p < 0.05). The lesser activity when the samples are incubated with Ni or Pb point out that these metals play a role in neoplasm development. In short, the oxidant-antioxidant balance is altered in lung cancer patients.     

Risk Analysis of a Farm Area Near a Lead- and Cadmium-Contaminated Industrial Site

The Asua Valley is an area on the outskirts of Bilbao where industry and small farms still coexist despite decades of serious environmental pollution. The present study was carried out to estimate the risk to which the residents of the area are exposed as a result of soil/dust ingestion and consumption of locally grown fresh produce, and, on the basis of this data, to delimit the areas that might require environmental clean-up. The relation between lead and cadmium content in soil and plant samples was assessed by multiple linear regression. The level of soil lead content for proposing intervention was determined by assessing the exposure of young children due to soil ingestion, assuming a “central-estimate” ingestion rate of 110?mg/day. Vegetable sampling was stratified according to the level of cadmium in the soil. The intervention content of cadmium was established as the midpoint of the soil sampling stratum previous to the one registering a vegetable consumption hazard quotient of 1; in this interval the intake reached 57% of the TDI.