background: waste produced in dental clinics has been the topic of investigations for many years. these waste materials have important health impacts and are hazardous to humans and the environment. objective: to investigating solid waste production and its management in dental clinics in gorgan, northern iran. methods: in this cross-sectional study, 45 of 143 public dental practices and 5 of 2...

introduction: recent investigations have detected the presence of significant levels of heavy metals (chromium, lead and cadmium) in toys and other pvc products manufactured for children. in some countries, addition of compounds containing toxic metals to toys are limited or prohibited. methods: to evaluate the safety of some of the plastic toys in the city of isfahan with respect to toxic trac...

The process of etching is the most crucial part of the work of manufacturing printed circuit boards (PCB). In the etching process by nitric acid, a spent etching waste solution of composition 250 g/L HNO3, 30-40 g/L Cu, 30-40 g/L Sn, 30-40 g/L Pb and 20-25 g/L Fe is produced. High metal concentrations in the spent etching waste solution make it a viable candidate for the recovery of metals. Rec...

Textile dye industry waste is one of the most serious problems in the environment. The dye wastes are severely deleterious to surface water bodies. The present study was an attempt for the assessment of different physicochemical parameters such as pH, temperature, Electrical Conductivity (EC), Total Solids (TS), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Dissolved Oxygen (DO), ...

13 Abstract Reactive waste dumps with sulfide minerals pro14 mote acid mine drainage (AMD), which results in water and 15 soil contamination by metals and metalloids. In these systems, 16 contamination is regulated by many factors, such as mineral17 ogical composition of soil and the presence of sorption sites 18 on specific mineral phases. So, the present study dedicates 19 itself to understan...

Mercury exposure is the second-most common cause of toxic metal poisoning. Public health concern over mercury exposure, due to contamination of fish with methylmercury and the elemental mercury content of dental amalgams, has long been a topic of political and medical debate. Although the toxicology of mercury is complex, there is evidence for antioxidant protection in the prevention of neurolo...

Bioleaching, a novel biotechnological process, is used to eliminate heavy metals from contaminated sediments by acidification as well as solubilization of heavy metals. Metals from poor-quality ore and mineral compounds are removed by Bioleaching process, which is simple and low cost effective technology. Acidophilic sulfur oxidizing bacteria (Acidithiobacillus ferrooxidans, Acidithiobacillus t...

Metals have been mined and used since ancient times. The industrial era has seen a sharp increase in both the amounts and variety of metals that find applications in industry. The inadvertent release of metals, such as from fossil fuel consumption, also adds to the global burden. A number of catastrophic outbreaks have alerted us to the occupational and environmental health risks. Life on this ...

A ll transition metals are highly toxic to life at low levels, but at the same time some, such as manganese, iron, cobalt, nickel, copper, zinc and molybdenum, are essential micronutrients needed to catalyse key enzymatic reactions. To survive, living organisms have had to evolve mechanisms that either remove such metals from their bodies or detoxify and make use of them metabolically. Many of ...

Composting is the best-known processes for biological stabilization of sewage sludge, municipal solid waste and other biodegradable wastes. Prepared compost can be used as a soil conditioner in agricultural applications. However, the presence of non-biodegradable and high level of toxic heavy metals in the compost frequently hinders agricultural land application. Uptake of heavy metals by plant...