How Lead Metal is Crucial Element in Various Applications
Lead (Pb) is a bluish-white soft lustrous metal, which is highly ductile, malleable and a comparatively poor conductor of electricity. It is resistant to corrosion but gets tarnished upon exposure to air. Lead is among the most notorious metals found in the earth’s crust. Today it is known more widely as the source of poisoning in humans, despite the metal being used by humans for thousands of years. Lead is soft, has a comparatively low melting point, can be easily shaped, and does not corrode much, making it extraordinarily useful. It is also quite abundantly found and can be extracted with much ease.
The hazards caused by lead have been known for centuries, but recently, science has revealed that even moderate levels of lead exposure can trigger cardiovascular and neurological disease, diminished kidney function, and infertility. In young kids particularly, traces of lead have been associated with behavioral and learning problems, low IQ, and other health problems that can continue a lifetime.
Health Effects of Lead
Lead is one of the four metals with the most harmful effects on human well-being. It can enter our bodies through food (65%), air (15%), and water (20%). Foods items such as vegetables, fruits, grains, meat, seafood, wine, and soft drinks may contain substantial quantities of lead. Smoking cigarettes can also cause small volumes of lead to enter the body.
Lead can enter the water through corroded pipes. The likelihood of lead entering the water is more when the water is a little acidic. That is why community water treatment plants are now needed to carry out pH adjustments in water. Lead can cause numerous undesirable effects, such as:
Behavioral disturbances in children, such as impulsive behavior, hyperactivity, and aggression
Reduced learning abilities among children
Weakened fertility among men as a result of sperm damage
Brain and kidney damage
Disruption of nervous systems
Miscarriages and abortions
High blood pressure
Disruption of the synthesis of haemoglobin and anaemia
Use of Lead
Lead can be used for various applications. It can be used to alloy with other metals, as an unadulterated metal or as chemical compounds. Here is a list of the various applications in which lead is used extensively:
Ammunition: Lead is used to make bullets and other ammunition that are extensively used in sport shooting with small arms.
Cable sheathing: Due to its decent extrusion ability, high ductility, comparatively low temperature & outstanding corrosion resistance when it comes in contact with a range of marine and industrial environments, and chemicals, lead alloys are used widely as sheathing materials for high voltage power cables.
Lead-acid battery: The primary consumption of lead is for lead-acid batteries in which the plate or grid is made of lead or lead alloys consisting of antimony.
Lead pipes: As a result of its corrosion-resistant features, lead is used for carrying corrosive substances at chemical plants. Lead pipes of suitable composition are extruded for cutting into short length 'sleeves' for joining lead sheathed cables.
Rolled extrusions: Lead sheets are utilized in the construction industry for weathering or flashings to stop water dispersion & for cladding and roofing. Since lead is resistant to corrosion, lead sheets are also used for the lining of acid plants, storage vessels, and chemical treatment baths. Lead sheet’s high density makes it a valuable material for the purpose of sound insulation. Lead clad steel is also used in radiation shielding.
Pigments: Lead pigments are used widely in paints, although lately the use of lead in paints has been significantly reduced because of health reasons. The most commonly used lead pigment is white lead. Lead chromates and lead sulfates are other lead pigments of importance.
Lead alloys: Lead alloys formed with copper, tin, antimony, arsenic, cadmium, sodium, and bismuth are all of industrial value. Lead is used to make solder, bearings, and antifriction metals. Lead foil is made with lead alloys and lead is added to brass to lower machine tool wear.
Environmental Consequences of Lead
In addition to leaded gasoline, other human actions, such as industrial manufacturing, solid waste combustion, and fuel combustion also increase lead concentrations in the environment.
Lead ends up in the water and pollutes the soil through lead corroded pipelines for transporting water and through the corrosion of leaded paints. The pollutants cannot be broken down and it can only be transformed into other forms.
Lead collects in the bodies of organisms in soil and water. It eventually, affects the health of shellfish and phytoplankton even when only small concentrations of lead are present. Phytoplankton is a key source of oxygen production in oceans and many large sea animals consume it. That is why it is believed that lead pollution can impact global balances.
Soil functions are disrupted by the accumulation of lead, especially near farmlands and highways, where excessive concentrations may be present. Organisms in the soil suffer from lead poisoning, too. Lead is a dangerous chemical, as it can not only accumulate in individual organisms, but also in the whole food chain.