What is the comparative form of “unpolluted”?

The comparative form of “unpolluted” is “less polluted”.

Example

The countryside is less polluted than the city.

Example

The air in the mountains is less polluted than in the industrial area.

What is the superlative form of “unpolluted”?

The superlative form of “unpolluted” is “the least polluted”.

Example

Among all the cities, this one is the least polluted.

Example

The beach is the least polluted place I've ever been to.

Why is this expression not used with most, more?

"The least" and "less" are used with "polluted" to form the comparatives and superlatives. The forms "less polluted" and "the least polluted" are commonly used to indicate a lower degree of pollution.

Does this expression have an irregular comparative/superlative form?

"Polluted" follows the regular pattern of using "less" and "the least" for forming comparatives and superlatives.

Expressions with similar meanings to “less polluted”

cleaner

Used to describe something that has a lower level of pollution or contamination.

Example

The water in the lake is cleaner than in the river.

purer

Used to indicate that something has a higher level of purity or cleanliness.

Example

The air in the forest is purer than in the urban area.

Expressions with similar meanings to “the least polluted”

the cleanest

Used to describe something that has the highest level of cleanliness or purity.

Example

This hotel has the cleanest rooms I've ever seen.

the purest

Used to indicate that something has the highest level of purity or cleanliness.

Example

The water from the spring is the purest I've tasted.

Using than with comparative “less polluted”

When using the comparative form "less polluted" to compare two things, you would use "than" to connect the two parts of the comparison: Example: "The countryside is less polluted than the city." Here, "than" is used to show that the level of pollution in "the countryside" is lower than the level of pollution in "the city."

How can I use this expression in context?

“less polluted” and “the least polluted” can be used in a variety of situations to compare speed.

1Locations
The park is less polluted than the busy intersection.
The park is less polluted than the busy intersection.
2Air Quality
The indoor air is the least polluted in the office building.
The indoor air is the least polluted in the office building.
3Water
The tap water is less polluted than the river water.
The tap water is less polluted than the river water.
4Environment
The national park is the least polluted area in the region.
The national park is the least polluted area in the region.