205
[4]. Heavy metals can also cause environmental pollution due to metal corrosion,
deposition of metals in the atmosphere, leaching of heavy metals, soil erosion of
heavy metals and metallic ions, re-suspension of sediments, and evaporation of
metals from water reservoirs to soil and groundwater [5]. These heavy metals can
accumulate in the human body by different processes and cause harmful effects on
them. These heavy metals have the ability to bind with macromolecules and alter
their normal cellular functions. It may lead to many adverse effects on the health of
humans by affecting their central nervous system, lungs, liver, and kidney [6]. In the
proceeding sections, we have briefly summarized the role of most important heaving metals that act as EDCs in metabolic disorders.
Cadmium
Sources and Exposure
Cadmium is a heavy metal that naturally occurs in ores. It generally acts as a stabilizer in many products such as polyvinyl chloride containing products, many
alloys, and color pigments. Phosphate fertilizers are also a major source of cadmium exposure [7]. The activities in the environment such as the burning of fossil
fuels, electroplating phenomena, usage and production of pigments and batteries
containing alkaline nickel-cadmium and welding have more contribution to acting
as a source of cadmium as compared to naturally occurring process in the environment. The naturally occurring processes such as volcanic activity, forest fires, erosion of soil, and weathering of rocks are major sources for releasing cadmium into
the environment [8]. The human being may be exposed to cadmium in several
ways (Fig. 13.1). Mining and smelting of non-ferrous metals and synthesis of
compounds containing cadmium are known as occupational sources of cadmium
exposure. Non- occupational sources of cadmium exposure may include smoking,
diet, and house dust [9].
Role of Cadmium on Carbohydrates Metabolism
Effect of Cadmium Glycolysis
Glycolysis is a process of conversion of a six-carbon compound into three-carbon
compounds. This process occurs in the cytoplasm [10]. Glucose is converted into
glucose-6-phosphate (G-6-P) by the mechanism of phosphorylation with the help of
an enzyme glucokinase [11]. The G-6-P is converted into fructose-6-phosphate
(F-6-P) by an enzyme phosphohexose isomerase. F-6-P is phosphorylated by an
enzyme phosphofructokinase to form fructose 1, 6-bisphosphate. Fructose 1,
13 Role of Heavy Metals in Metabolic Disorders
[4]. Heavy metals can also cause environmental pollution due to metal corrosion,
deposition of metals in the atmosphere, leaching of heavy metals, soil erosion of
heavy metals and metallic ions, re-suspension of sediments, and evaporation of
metals from water reservoirs to soil and groundwater [5]. These heavy metals can
accumulate in the human body by different processes and cause harmful effects on
them. These heavy metals have the ability to bind with macromolecules and alter
their normal cellular functions. It may lead to many adverse effects on the health of
humans by affecting their central nervous system, lungs, liver, and kidney [6]. In the
proceeding sections, we have briefly summarized the role of most important heaving metals that act as EDCs in metabolic disorders.
Cadmium
Sources and Exposure
Cadmium is a heavy metal that naturally occurs in ores. It generally acts as a stabilizer in many products such as polyvinyl chloride containing products, many
alloys, and color pigments. Phosphate fertilizers are also a major source of cadmium exposure [7]. The activities in the environment such as the burning of fossil
fuels, electroplating phenomena, usage and production of pigments and batteries
containing alkaline nickel-cadmium and welding have more contribution to acting
as a source of cadmium as compared to naturally occurring process in the environment. The naturally occurring processes such as volcanic activity, forest fires, erosion of soil, and weathering of rocks are major sources for releasing cadmium into
the environment [8]. The human being may be exposed to cadmium in several
ways (Fig. 13.1). Mining and smelting of non-ferrous metals and synthesis of
compounds containing cadmium are known as occupational sources of cadmium
exposure. Non- occupational sources of cadmium exposure may include smoking,
diet, and house dust [9].
Role of Cadmium on Carbohydrates Metabolism
Effect of Cadmium Glycolysis
Glycolysis is a process of conversion of a six-carbon compound into three-carbon
compounds. This process occurs in the cytoplasm [10]. Glucose is converted into
glucose-6-phosphate (G-6-P) by the mechanism of phosphorylation with the help of
an enzyme glucokinase [11]. The G-6-P is converted into fructose-6-phosphate
(F-6-P) by an enzyme phosphohexose isomerase. F-6-P is phosphorylated by an
enzyme phosphofructokinase to form fructose 1, 6-bisphosphate. Fructose 1,
13 Role of Heavy Metals in Metabolic Disorders