Bioremediation

Bioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi in mycoremediation, and plants in phytoremediation), living or dead, is employed for removing environmental pollutants from air, water, soil, flue gasses, industrial effluents etc., in natural or artificial settings.[1] The natural ability of organisms to adsorb, accumulate, and degrade common and emerging pollutants has attracted the use of biological resources in treatment of contaminated environment.[1] In comparison to conventional physicochemical treatment methods bioremediation may offer advantages as it aims to be sustainable, eco-friendly, cheap, and scalable.[1]

Most bioremediation is inadvertent, involving native organisms. Research on bioremediation is heavily focused on stimulating the process by inoculation of a polluted site with organisms or supplying nutrients to promote their growth. Environmental remediation is an alternative to bioremediation.[2]

While organic pollutants are susceptible to biodegradation, heavy metals cannot be degraded, but rather oxidized or reduced. Typical bioremediations involves oxidations.[3][4] Oxidations enhance the water-solubility of organic compounds and their susceptibility to further degradation by further oxidation and hydrolysis. Ultimately biodegradation converts hydrocarbons to carbon dioxide and water.[5] For heavy metals, bioremediation offers few solutions. Metal-containing pollutant can be removed, at least partially, with varying bioremediation techniques.[6] The main challenge to bioremediations is rate: the processes are slow.[7]

Bioremediation techniques can be classified as (i) in situ techniques, which treat polluted sites directly, vs (ii) ex situ techniques which are applied to excavated materials.[8] In both these approaches, additional nutrients, vitamins, minerals, and pH buffers are added to enhance the growth and metabolism of the microorganisms. In some cases, specialized microbial cultures are added (biostimulation). Some examples of bioremediation related technologies are phytoremediation, bioventing, bioattenuation, biosparging, composting (biopiles and windrows), and landfarming. Other remediation techniques include thermal desorption, vitrification, air stripping, bioleaching, rhizofiltration, and soil washing. Biological treatment, bioremediation, is a similar approach used to treat wastes including wastewater, industrial waste and solid waste. The end goal of bioremediation is to remove harmful compounds to improve soil and water quality.[9]

  1. ^ a b c Yuvraj (2022). "Microalgal Bioremediation: A Clean and Sustainable Approach for Controlling Environmental Pollution". Innovations in Environmental Biotechnology. Vol. 1. Singapore: Springer Singapore. pp. 305–318. doi:10.1007/978-981-16-4445-0_13. ISBN 978-981-16-4445-0.
  2. ^ "Green Remediation Best Management Practices: Sites with Leaking Underground Storage Tank Systems. EPA 542-F-11-008" (PDF). EPA. June 2011.
  3. ^ Duran N, Esposito E (2022). "Potential Applications of Oxidative Enzymes and Phenoloxidase-like Compounds in Wastewater and Soil Treatment: A Review". Applied Catalysis B: Environmental. 1 (2): 305–318. doi:10.1016/S0926-3373(00)00168-5.
  4. ^ Singh N, Kumar A, Sharma B (2019). "Role of Fungal Enzymes for Bioremediation of Hazardous Chemicals". Recent Advancement in White Biotechnology Through Fungi. Fungal Biology. Vol. 3. Cham: Springer International Publishing. pp. 237–256. doi:10.1007/978-3-030-25506-0_9. ISBN 978-3-030-25506-0. S2CID 210291135.
  5. ^ Cite error: The named reference EPA_2013 was invoked but never defined (see the help page).
  6. ^ Kapahi M, Sachdeva S (December 2019). "Bioremediation Options for Heavy Metal Pollution". Journal of Health and Pollution. 9 (24): 191203. doi:10.5696/2156-9614-9.24.191203. PMC 6905138. PMID 31893164.
  7. ^ Cite error: The named reference Norris_1993 was invoked but never defined (see the help page).
  8. ^ Kensa VM (2011). "Bioremediation - An Overview". I Control Pollution. 27 (2): 161–168. ISSN 0970-2083.
  9. ^ Canak S, Berezljev L, Borojevic K, Asotic J, Ketin S (2019). "Bioremediation and "green chemistry"". Fresenius Environmental Bulletin. 28 (4): 3056–3064.