Living close to motorways in Kent can affect children's school performance, according to a new survey.

The seven-month investigation by Maidstone Borough Council looked into the effects of noise from the M2 and M20.

Initial tests found sound levels were way above what was expected and enough to affect school pupils' performance.

Councillor Tony Harwood, heading the investigation, said: "Some of the readings are really quite disturbing."

Some of the readings are really quite disturbing Councillor Tony Harwood

Levels were also high enough to disturb sleep and make people irritable.

The investigation, which is still in progress, also looked at air pollution and the effects of debris such as remnants of tyres left on roads.

Health experts specialising in pollution and psychologists were among those consulted by the council.

The council was particularly keen to look at the effects of noise, as it felt noise from motorways had previously been overshadowed by investigations into noise pollution from airports.

Dover's port means more traffic for Kent

It sees Kent as an area particularly affected by motorway traffic, as the county's roads are used by a high number of HGVs heading to and from the port at Dover and the Channel Tunnel.

Previous research has found noise of 40-55 decibels makes people annoyed, up to 60 decibels disturbs sleep and levels of up to 70 could affect health and school performance.

Noise of 60 to 70 decibels was found to be commonplace in tests taken in residential areas near the Kent motorways.

Experts from the EU and the Highways Agency will be consulted before the project reaches its final conclusions in the spring.