The group had installed diffusion tubes near key roads in Adur to measure levels of nitrogen dioxide in the air, against the annual mean legal limit of 40 micrograms per cubic meter (µg/m3).
At the Ropetackle Centre meeting on Thursday, group member Gerard Rosenberg said the findings were ‘quite shocking’.
Coordinator Barb O’ Kelly said that out of three locations monitored on Shoreham high street, all readings were above 40µg/m3 and one was above 50µg/m3.
“This is really important because it affects the lungs and health of all of us every time we walk down the high street,” she said.
A traffic count on the high street found that an average of 15,383 vehicles used the road over a 12-hour period – which was far more than expected, said coordinator Geoff Hodgson.
In Lancing, Bill Freeman revealed that eight results out of 36 measured were ‘well over’ 40µg/m3, with one over 50µg/m3 – findings that he said ‘raised alarm bells’.
Proposed developments at New Monks Farm and the airport would create ‘additional pollution and an even greater health hazard for the community’, he said, and ‘must simply not be allowed to take place’.
Nadeem Shad, environment team leader at Adur District Council, said the council were working to update their Area Quality Action Plan, which aims to reduce pollution levels, particularly in council-identified hotspots Shoreham high street and Old Shoreham Road in Southwick.
Strategies included looking at traffic light sequencing, car club schemes and improving walking and cycling routes.
A council application for a feasibility study into charging clean air zones had been unsuccessful, he said.
Mr Rosenberg said the group hoped ‘to create a dialogue’ with both councils, as well as the public, so as to tackle the issue together.