Pollution

Pollution is the introduction of contaminants into the natural environment that cause adverse change.^[1] Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Pollution is often classed as point source ornonpoint source pollution.

"Waste-water from the houses collected in the gutters running alongside the curbs and emitted a truly fearsome smell. There were no public toilets in the streets or squares. Visitors, especially women, often became desperate when nature called. In the public buildings the sanitary facilities were unbelievably primitive....As a metropolis, Berlin did not emerge from a state of barbarism into civilization until after 1870."^[7]

https://en.wikipedia.org/wiki/Pollution

Reflection :
Plant some trees, do not smoke ,


summary :

Pollution is the introduction of contaminants into the natural environment that cause adverse change.^[1] Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Pollution is often classed as point source ornonpoint source pollution.