A combination of global and local cumulative phenomena is at the origin of a spectacular growth of jellyfish populations in recent years, preparing for a potential global ecological disaster.

• As a result of over-fishing, predators of jellyfish, like swordfish and red tuna, see a drastic reduction of their populations. Some fishing practices have also a negative impact on sardines and whitebait that compete for food with jellyfish.

• Warmer waters and shorter winters in some parts of the globe as well as the acidification of oceans impact calcium and shell-forming marine life, in particular marine turtle, one of the most important predators of jellyfish.

• Pollution and unsound waste management have the characteristics of overloading coastal waters with nutrients from agriculture and sewage, and contaminating waters with pesticides and industrial toxic chemicals that destroy marine life to the benefit of jellyfish that accommodate better to a polluted environment than fish.

• Tourism and coastal development can impact negatively on the reproduction of marine turtles on beaches.

The way used tyres are managed and recycled is a fascinating subject: into adhesives, insulation, brake linings, conveyor belts, in serving to pad out children's play areas, in asphalt paving and road construction, or complement to football artificial turf surface, to retreading, regrooving and energy resources to supplement fuel in pulp and paper mills, industrial boilers, cement kilns or power plants.

There is however a negative aspect to the positive role played by the recycling and retreading of used tyres. Used tyres are being exported or imported in large quantities and such trade is expanding. Trade in used tyres, stockpiles and discarded tyres have long been recognised as increasing the worldwide dispersal of invasive mosquito species and generating local outbreak of malaria or chikungunya.