Question

why do we say that burning of fuels can cause health hazards

Answer 1

Burning Fossil fuels like coal, petroleum products and Natural gas leads to releasing of pollutants in air which leads to air pollution and effects

Answer 2

These particles are very dangerous pollutants and cause respiratory diseases for example asthma. When fuels are incompletely burnt, they release carbon monoxide gas into the atmosphere. ... Burning of coal and diesel releases sulphur dioxide gas.