Some nine hundred years ago a green Greek Cross emblem was used by the Hospitallers of St. Lazarus. Centuries later Islam adopted green as a symbol of nature and life; a common understanding, irrespective of religion.
To represent life in a spiritual sense there is no more suitable colour than green1. However, since it is a special colour for Muslims, green crosses are now rarely seen in a Christian context, even in places like Ireland, where green is very much a national colour2 and Catholicism is the predominant denomination.
Exceptions are seen in the emblems of Baptist churches in Rwanda, who use a green cross in their group logo (AEBR) aebrwanda.com/, the restorationist Harpeth Community Church in Franklin, Tennessee, USA (HCC) harpethcc.com, and also the Reformed Church in America (RCA) rca.org.
Generally today, a green cross has a secular meaning and the most common use is health care. In particular, the green cross represents First Aid.
The Red Cross of the International Federation of Red Cross and Red Crescent Societies is an emblem protected under the Geneva Conventions Act and cannot be used without permission. Contrary to popular belief, the Red Cross is not a public domain First Aid symbol.
The International Standards Organisation3 recommends that a white cross on green background is used as a First Aid symbol4. (See also the emergency services' Star of Life.)
A variation is a green cross on a white field5. Although this is not recommended by ISO, it is still widely recognised as a first aid symbol.
Green is commonly adopted by environmentalists and in 1986 one such group in Taiwan joined with liberals to form the Democratic Progressive Party (DPP). Their banner is a green outline of Taiwan within a white cross on a green ground. Part of their agenda is anti-Communism and it just so happens that on the opposite side of the colour wheel is red, the predominant colour of the People's Republic of China flag.
A few years later another environmental group used the green cross in their emblem; the Green Cross International (GCINT) organisation, founded in 1993 by the former Soviet leader, Mikhail Gorbachev. This group has branches around the world, yet in many countries the green cross symbol has been used by conservation and welfare organisations since much earlier than 1993.
In Germany, for example, is the Deutsches Grünes Kreuz e.V. (German Green Cross) was founded in 1948. It does not restrict itself to human health, but also has concern for the protection of animals and plants.
In Korea is the headquarters of the Green Cross Corp, named as such since 1971, and whose main business is pharmaceuticals.
In Japan a flag with a green cross (midori-juji6) on a white field is frequently flown on construction sites and factories to encourage workers to remember health and safety. It also appears on badges and arm bands for the same purpose and is occasionally seen as a cross-within-a-cross.
The poster on the right, for example, was seen in Oimachi station, Tokyo, to announce the government's health / safety / sanitation measures.
Ironically, a green cross was used to identify the contents of a deadly artillery gas shell during World War I. These were fired by the British and German armies in Europe and released suffocating gasses7.
Also ironically, green is one of the most toxic colours there is for dyeing fabrics, paper, plastics, and many other materials used for packing 'green' products. According to the German chemist Michael Braungart design book "Cradle to Cradle", it is impossible to dye such products without contaminating them. Composting or recycling such products will contaminate other material. Green is not very environmentally friendly.
The most common green shade used in plastic is Pigment Green 7; it is organic but contains chlorine and is linked to cancer and birth defects. Pigment Green 36 contains chlorine and bromide, and Pigment Green 50 contains cobalt, titanium nickel and zinc oxide. Older pigments used by artists contained arsenic. Indeed, such poison is believed to have caused the death of Napoleon.
Is this nature's way of saying to mankind that trying to replicate nature, even the colours of nature, can lead to doom?
Maybe. But don't let any of this stop you from reaching for the First Aid Box (with its green cross) when you need to!