ABSTRACT
BACKGROUND: This paper presents micro- and nano-fabrication techniques for leachable realgar using the extremophilic bacterium Acidithiobacillus ferrooxidans (A. ferrooxidans) DLC-5. RESULTS: Realgar nanoparticles of size ranging from 120 nm to 200 nm were successfully prepared using the highenergy ball mill instrument. A. ferrooxidans DLC-5 was then used to bioleach the particles. The arsenic concentration in the bioleaching system was found to be increased significantly when compared with that in the sterile control. Furthermore, in the comparison with the bioleaching of raw realgar, nanoparticles could achieve the same effect with only one fifth of the consumption. CONCLUSION: Emphasis was placed on improving the dissolvability of arsenic because of the great potential of leachable realgar drug delivery in both laboratory and industrial settings
Subject(s)
Arsenic/metabolism , Sulfides/metabolism , Acidithiobacillus/metabolism , Mining/methods , Arsenic/chemistry , Solubility , Sulfides/chemistry , Temperature , Nanotechnology , Nanoparticles/chemistry , ExtremophilesSubject(s)
Adult , Child , Humans , Environmental Pollutants , Mercury , Mining , Metallurgy/methods , Air Pollutants, Occupational/adverse effects , Biotransformation , Bacteria/metabolism , Colombia , Environment , Environmental Policy , Environmental Pollutants/adverse effects , Gold , Industrial Waste/adverse effects , Mercury Poisoning/epidemiology , Mercury Poisoning/etiology , Mercury/metabolism , Methylmercury Compounds/metabolism , Methylmercury Compounds/poisoning , Methylmercury Compounds/toxicity , Mining/methods , Occupational Diseases/epidemiology , Occupational Diseases/etiologyABSTRACT
Economic development, including resource extraction, can cause toxic exposures that interact with endemic infectious diseases. Mercury is an immunotoxic metal used in the amalgamation of gold, resulting in both occupational exposures and environmental pollution. A cross-sectional medical survey was conducted in 1997 on 135 garimpeiros in Para, Brazil, because of their risks of both mercury exposure and malaria transmission. Mean levels of blood and urine mercury were well above non-exposed background levels. Twenty-six subjects had malaria parasitemia: Health symptoms consistent with mercury exposure were reported, but neither symptoms nor signs correlated with mercury levels in blood or urine. We did not find a dose response relationship between mercury exposure and likelihood of prevalent malaria infection, but there was a possible reduction in acquisition of immunity that may be associated with conditions in gold mining, including mercury exposure
Subject(s)
Adolescent , Adult , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Gold , Malaria/epidemiology , Mercury/adverse effects , Mining/methods , Occupational Exposure/adverse effects , Brazil/epidemiology , Cross-Sectional Studies , Malaria/etiology , Mercury/blood , Mercury/urine , Occupational Exposure/analysis , Prevalence , Parasitemia/blood , Parasitemia/epidemiology , Plasmodium/isolation & purificationABSTRACT
El programa es el resultado del análisis de la contaminación ambiental causada por la industria minera en general y de la mineria pequeña en particular, esta destinado a brindar apoyo y asistencia directa a los mineros pequeños concientizandolos sobre el problema ambiental en sus operaciones, desarrollando, probando y difundiendo tecnologias para la proteccion del medio ambiente.(au)