What is Biochemistry?
Biochemistry is a multidiscipline field that studies the chemistry of life processes. These processes can be loosely divided into the following groups: reactions that are anabolic (build up molecules) or catabolic (break down molecules), chemistry of regulatory pathways (hormones and genes) and the chemistry of cell structure. At the cellular level the reactions include oxidation/reduction reactions, group transfer, hydrolysis, bond making and breaking reactions. On the systemic level the reaction represent pathways and processes in living system that are important in the energy transfer, biological information flow, protein structures, oxygen flow, and catalysis of reactions. These predefined reactions, processes, pathways and systems all function together enabling the living system to function normally.
Xenobiotics the Common Thread
Biochemistry is used in Environmental Science when understanding the environment’s effect on living organisms as they interact with environmental pollutants. The pollutants sometimes referred to as xenobiotics can be ingested, inhaled or absorbed through the skin. Using biochemistry it is possible to study how the different pollutants behave once they are in the body. Where they are transformed, eliminated or stored and how this can affect the different biological process of a normally functioning organism. Xenobiotics studied include pesticides, hazardous wastes, synthetic and natural compounds.
Biochemistry in Environmental Science
Through biochemistry we have been able to determine that some xenobiotics like PCB, Dioxins and DDT once in the body mimic hormones disrupting the body’s normal function. With this information the EPA Okayed the removal of polychlorinated biphenyls or PCBs from several rivers in the United States. The latest was a successful cleanup of the Kalamazoo River in Michigan. The dredging of the river began in June 2007 and is expected to be finished in December 2008. The goal is to create a cleaner PCB-free ecosystem.
Biochemistry is used in Environmental Science to identify biological markers (biomarkers) in genes, blood or urine that can be used to determine exposure, toxic effect, and susceptibility to certain classes of xenobiotics. Biomarkers were used November 2008 to help British Columbia fisheries in managing salmons spawning grounds. The project titled “Genomic Tools for Fisheries Management" combines genetic information with environmental data. The researchers use genetic biomarkers to asses the health of the salmon to see the effects of pollution on the salmon’s health and spawning habits.
Biomagnification and bioaccumulation are important processes of xenobiotics that occur in living systems. In the April 2008 issue of the journal Science, there is an article on a study showing the bioaccumulation of mercury through the terrestrial food chain of birds. Mercury is a notoriously toxic pollutant. Other important biochemical processes that are affected through environmental exposure to toxins are cell damage and cell death. The cell damage mechanism is due to xenobiotics which are sometimes carcinogenic.