The industry, which employs some 14 million people worldwide, is booming in the US and Europe as companies are lured by low prices and new technology.

But in many areas of the US, cleaning is not being performed to the high standards required to prevent contamination.

The World Health Organisation says a third of Americans still do not have access to clean water.

What’s more, there is a growing concern that the contamination is being ignored by companies, leaving the environment and the workers exposed to dangerous levels of chemicals.

This is despite the fact that the industry has been around for centuries and was a key part of the industrial revolution.

But now, as the US economy has grown and manufacturing is becoming more diverse, cleaning services are starting to come under pressure.

This article first appeared on the BBC World Service.

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