says we have 219 toxic pollutants in our bodies, and this includes preservatives, pesticides and heavy metals like lead and mercury.

For example, the authors of The Limits to Growth predicted that before 2013, the world would have run out of aluminum, copper, gold, lead, mercury, molybdenum, natural gas, oil, silver, tin, tungsten, and zinc.

Heavy metals (aluminium, chromium, arsenic, and copper) dissolved in the water as a result of coal burning were deemed to be at acceptable levels, but metals in sediment and mercury in larger pike were found to be excessive.

In addition, some countries specify as air pollutants heavy metals (such as lead and mercury), volatile organic compounds (such as benzene and formaldehyde) and a broad array of other chemical compounds classified as air toxics.

Chemical exposures can also interfere with primary education by impairing children's physical growth and emotional development and, in the case of metals such as lead and mercury, can have serious and irreversible adverse effects on children's mental development.

Gas emits less than half the CO2 per kWh produced, and it emits much lower amounts of other pollutants like NOx, SO2, black carbon, CO, mercury, and particulates. If the UK sold its shale gas both domestically and abroad to replace coal, it could reduce local air pollution significantly and reduce global carbon emissions by 170Mt, or more than a third of UK carbon emissions.

For example, the classic 1972 bestseller Limits to Growth predicted that the world would run out of gold in 1981, silver and mercury in 1985, and zinc in 1990.

That message still resonates today, though it was spectacularly wrong. For example, the authors of The Limits to Growth predicted that before 2013, the world would have run out of aluminum, copper, gold, lead, mercury, molybdenum, natural gas, oil, silver, tin, tungsten, and zinc.

Occurrence Iridium is one of the nine least abundant stable elements in Earth's crust, having an average mass fraction of 0.001 ppm in crustal rock gold is 40 times more abundant, platinum is 10 times more abundant, and silver and mercury are 80 times more abundant.