page_title: Bioremediation of radioactive waste
section_title: Ecological and human health consequences
hierarchical_section_title: Bioremediation of radioactive waste / Areas contaminated by radioactivity / Ecological and human health consequences
caption_attribution_description: English: Female hand showing deformity due to x-ray burns. The inflammation of the fingers are due to excessive radiation, which occurs when x-ray machines are unshielded.
context_page_description: Bioremediation of radioactive waste or bioremediation of radionuclides is an application of bioremediation based on the use of biological agents bacteria, plants and fungi to catalyze chemical reactions that allow the decontamination of sites affected by radionuclides. These radioactive particles are by-products generated as a result of activities related to nuclear energy and constitute a pollution and a radiotoxicity problem due to its unstable nature of ionizing radiation emissions.
  The techniques of bioremediation of environmental areas as soil, water and sediments contaminated by radionuclides are diverse and currently being set up as an ecological and economic alternative to traditional procedures. Physico-chemical conventional strategies are based on the extraction of waste by excavating and drilling, with a subsequent long-range transport for their final confinement. These works and transport have often unacceptable estimated costs of operation that could exceed a trillion dollars in the US and 50 million pounds in the UK.
context_section_description: Radioactive contamination is a potential danger for living organisms and results in external hazards, concerning radiation sources outside the body, and internal dangers, as a result of the incorporation of radionuclides inside the body (often by inhalation of particles or ingestion of contaminated food).
  In humans, single doses from 0.25 Sv produce first anomalies in the amount of leukocytes. This effect is accentuated if the absorbed dose is between 0.5 and 2 Sv, in whose first damage, nausea and hair loss are suffered. The strip ranging between 2 and 5 Sv is considered the most serious and include bleeding, ulcers and risk of death; values exceeding 5 Sv involve immediate death. If radiation, likewise, is received in small doses over long periods of time, the consequences can be equally severe. It is difficult to quantify the health effects for doses below 10 mSv, but it has been shown that there is a direct relationship between prolonged exposure and cancer risk (although there is not a very clear dose-response relationship to establish clear limits of exposure).
  The information available on the effect of natural background radiation with respect anthropogenic pollution on wildlife is scarce and refers to very few species. It is very difficult to estimate from the available data the total doses that can accumulate during specific stages of the life cycle (embryonic development or reproductive age), in changes in behavior or depending on environmental factors such as seasonality. The phenomena of radioactive bioaccumulation, bioconcentration and biomagnification, however, are especially known to sea level. They are caused by the recruitment and retention of radioisotopes by bivalves, crustaceans, corals and phytoplankton, which then amounted to the rest of the food chain at low concentration factors.
  Radiobiological literature and IAEA establish a safe limit of absorbed dose of 0.001 Gy/d for terrestrial animals and 0.01 Gy/d for plants and marine biota, although this limit should be reconsidered for long-lived species with low reproductive capacity.
  Radiation tests in model organisms that determine the effects of high radiation on animals and plants are:
  Chromosomal aberrations.
  DNA damage.
  Cancer, particularly leukemia.
  Leukopenia.
  Growth reduction.
  Reproductive deficiencies: sterility, reduction in fecundity, and occurrence of developmental abnormalities or reduction in viability of offspring
  Reduced seed germination.
  Burned tissues exposed to radiation.
  Mortality, including both acute lethality and long-term reduction in life span.
  The effects of radioactivity on bacteria are given, as in eukaryotes, by ionization of water and production of reactive oxygen species. These compounds mutate DNA strands and produce genetic damage, inducing newly lysis and subsequent cell death.
  Its action on viruses, on the other hand, results in damaged nucleic acids and viral inactivation. They have a sensory threshold ranging between 1000 and 10,000 Gy (range occupying most biological organisms) which decreases with increasing genome size.
caption: Deformity of hand due to an X-ray burn.
exif: {"Image Orientation": "Horizontal (normal)", "Image XResolution": "800", "Image YResolution": "800", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop Elements 6.0 Windows", "Image DateTime": "2009:01:19 12:43:14", "Image ExifOffset": "172", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "310", "Thumbnail JPEGInterchangeFormatLength": "3130", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2214", "EXIF ExifImageLength": "2467"}