(e) Temperature: Temperature affects biochemical reaction rates, and the rates
double for each 1
C rise in temperature; optimum temperature range is from
15 to 45
C.
(f) Oxygen: It plays an important role in initial breakdown of contaminants and in
the growth of microorganisms. It also determines whether the process is aerobic
or anaerobic in nature.
6 Conclusion
Cadmium due to its nonbiodegradable nature persists in the environment and
becomes part of the food chain. Higher concentration of cadmium in environment
leads to various types of toxicity to humans, plants, and animals. Bioremediation
now a day is used for cleanup of metal-contaminated and metal-polluted ecosystem.
Microorganisms like algae, bacteria, and fungi bioremediate heavy metals by various
processes like complexation, biosorption, absorption, flocculation, cation/anion
exchange, and oxidation–reduction reaction. The isolation of heavy metal-resistant
microorganisms and the understanding of the mechanisms they use in order to
remove pollutants may contribute to the development of improved bioremediation
processes. The use of resistant plants along with application of microorganism in the
soil would become a good mixing technique for better remediation. Biotechnological
approaches like formation of genetically modified plants and microbes which tolerate high level of cadmium are key factors in the future to reduce the environmental
burden of toxic substances. Due to industrialization, heavy metal pollution is
increasing at an alarming rate, so development of cost-effective and eco-friendly
remediation methods for heavy metal-polluted sites is an urgent need of the hour.
References
Abbas SZ, Rafatullah M, Ismail N, Lalung J (2014) Isolation, identification, and characterization of
cadmium resistant Pseudomonas sp. M3 from industrial wastewater. J Waste Manag:1–6.
https://doi.org/10.1155/2014/160398
Abhilash PC, Jamil S, Singh N (2009) Transgenic plants for enhanced biodegradation and
phytoremediation of organic xenobiotics. Biotechnol Adv 27:474–488
Agency for Toxic Substances and Disease Registry (1999) Toxicological profile for cadmium. US
Department of Human and Health Services
Ahner BA, Wei L, Oleson JR, Ogura N (2002) Glutathione and other low molecular weight thiols in
marine phytoplankton under metal stress. Mar Ecol Prog Ser 232:93–103
Aksu Z, Kustal TA (1991) Bioseparation process for removing lead ions from wastewater by using
Chlorella vulgaris. J Chem Technol Biotechnol 52:109–118
Alfvén T, Järup L, Elinder CG (2002) Cadmium and lead in blood in relation to low bone mineral
density and tubular proteinuria. Environ Health Perspect 110(7):699–702
Alfvén T, Elinder CG, Hellström L, Lagarde F, Järup L (2004) Cadmium exposure and distal
forearm fractures. J Bone Miner Res 19(6):900–908
15 Cadmium as an Environmental Pollutant: Ecotoxicological Effects, Health. . .
379
double for each 1
C rise in temperature; optimum temperature range is from
15 to 45
C.
(f) Oxygen: It plays an important role in initial breakdown of contaminants and in
the growth of microorganisms. It also determines whether the process is aerobic
or anaerobic in nature.
6 Conclusion
Cadmium due to its nonbiodegradable nature persists in the environment and
becomes part of the food chain. Higher concentration of cadmium in environment
leads to various types of toxicity to humans, plants, and animals. Bioremediation
now a day is used for cleanup of metal-contaminated and metal-polluted ecosystem.
Microorganisms like algae, bacteria, and fungi bioremediate heavy metals by various
processes like complexation, biosorption, absorption, flocculation, cation/anion
exchange, and oxidation–reduction reaction. The isolation of heavy metal-resistant
microorganisms and the understanding of the mechanisms they use in order to
remove pollutants may contribute to the development of improved bioremediation
processes. The use of resistant plants along with application of microorganism in the
soil would become a good mixing technique for better remediation. Biotechnological
approaches like formation of genetically modified plants and microbes which tolerate high level of cadmium are key factors in the future to reduce the environmental
burden of toxic substances. Due to industrialization, heavy metal pollution is
increasing at an alarming rate, so development of cost-effective and eco-friendly
remediation methods for heavy metal-polluted sites is an urgent need of the hour.
References
Abbas SZ, Rafatullah M, Ismail N, Lalung J (2014) Isolation, identification, and characterization of
cadmium resistant Pseudomonas sp. M3 from industrial wastewater. J Waste Manag:1–6.
https://doi.org/10.1155/2014/160398
Abhilash PC, Jamil S, Singh N (2009) Transgenic plants for enhanced biodegradation and
phytoremediation of organic xenobiotics. Biotechnol Adv 27:474–488
Agency for Toxic Substances and Disease Registry (1999) Toxicological profile for cadmium. US
Department of Human and Health Services
Ahner BA, Wei L, Oleson JR, Ogura N (2002) Glutathione and other low molecular weight thiols in
marine phytoplankton under metal stress. Mar Ecol Prog Ser 232:93–103
Aksu Z, Kustal TA (1991) Bioseparation process for removing lead ions from wastewater by using
Chlorella vulgaris. J Chem Technol Biotechnol 52:109–118
Alfvén T, Järup L, Elinder CG (2002) Cadmium and lead in blood in relation to low bone mineral
density and tubular proteinuria. Environ Health Perspect 110(7):699–702
Alfvén T, Elinder CG, Hellström L, Lagarde F, Järup L (2004) Cadmium exposure and distal
forearm fractures. J Bone Miner Res 19(6):900–908
15 Cadmium as an Environmental Pollutant: Ecotoxicological Effects, Health. . .
379