The Romans made pewter dishes and pipes for water from lead. While lead is a very useful metal, is also poisonous. The effects of poisoning from lead leaching into liquids may have contributed to the fall of the Roman empire. Lead exposure didn't end when lead-based paint and leaded gasoline were phased out.
It is still found in the insulation coating electronics, leaded crystal, storage batteries, on the coating of some candles wicks, as certain plastics stabilizers, and in soldering. You are exposed to trace amounts of lead every day. Lead is toxic mainly because it preferentially replaces other metals e. It interferes with the proteins that cause certain genes to turn on and off by displacing other metals in the molecules.
This changes the shape of the protein molecule such that it can't perform its function. Research is ongoing to identify which molecules bind with lead. Some of the proteins known to be affected by lead regulate blood pressure, which can cause developmental delays in children and high blood pressure in adults , heme production which can lead to anemia , and sperm production possibly implicating lead in infertility.
Lead displaces calcium in the reactions that transmit electrical impulses in the brain, which is another way of saying it diminishes your ability to think or recall information. Paracelsus' was a self-proclaimed alchemist in the s and pioneered the use of minerals in medical practices.
From its position in a table of electrode potentials, one would expect lead to replace hydrogen from acids. But the difference in electrode potentials between the two elements is so small 0. The element does tend to react with oxygen-containing acids more readily, but only because of oxidation that may take place at the same time. Health effects on shellfish can take place even when only very small concentrations of lead are present.
Body functions of phytoplankton can be disturbed when lead interferes. Phytoplankton is an important source of oxygen production in seas and many larger sea-animals eat it. That is why we now begin to wonder whether lead pollution can influence global balances. Soil functions are disturbed by lead intervention, especially near highways and farmlands, where extreme concentrations may be present.
Soil organisms than suffer from lead poisoning, too. Lead is a particularly dangerous chemical, as it can accumulate in individual organisms, but also in entire food chains. For more effects on freshwater ecosystem take a look at lead in freshwater. Read more on lead in water Back to periodic chart. More from 'Elements'. Toggle navigation. Home Periodic table Elements Lead.
About Lenntech. General Delivery Conditions. Privacy Policy. All rights reserved. The oxidation state of an atom is a measure of the degree of oxidation of an atom. It is defined as being the charge that an atom would have if all bonds were ionic. Uncombined elements have an oxidation state of 0. The sum of the oxidation states within a compound or ion must equal the overall charge.
Data for this section been provided by the British Geological Survey. An integrated supply risk index from 1 very low risk to 10 very high risk. This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores.
The percentage of a commodity which is recycled. A higher recycling rate may reduce risk to supply. The availability of suitable substitutes for a given commodity. The percentage of an element produced in the top producing country.
The higher the value, the larger risk there is to supply. The percentage of the world reserves located in the country with the largest reserves. A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K.
A measure of the stiffness of a substance. It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. A measure of how difficult it is to deform a material. It is given by the ratio of the shear stress to the shear strain. A measure of how difficult it is to compress a substance. It is given by the ratio of the pressure on a body to the fractional decrease in volume. A measure of the propensity of a substance to evaporate.
It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site.
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Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Glossary Group A vertical column in the periodic table. Fact box. Group 14 Melting point Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements. Appearance The description of the element in its natural form.
Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation. Lead has been known to, and used by, humans for many centuries. This long history is reflected in the image by the use of an early alchemical symbol for lead and carved Ancient Roman characters.
A dull, silvery-grey metal. It is soft and easily worked into sheets. This easily worked and corrosion-resistant metal has been used for pipes, pewter and paint since Roman times. It has also been used in lead glazes for pottery and, in this century, insecticides, hair dyes and as an anti-knocking additive for petrol.
All these uses have now been banned, replaced or discouraged as lead is known to be detrimental to health, particularly that of children. Lead is still widely used for car batteries, pigments, ammunition, cable sheathing, weights for lifting, weight belts for diving, lead crystal glass, radiation protection and in some solders.
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