Plans to build about 400 houses on former green belt land in Cheshire have been approved despite concerns about air quality.
They will be built on land at Henbury near Macclesfield, which lost green belt status to meet housing targets.
Opponents claimed the development would worsen local pollution levels, which already breach government guidelines.
The homes' developers said the town needed new homes and they would alter road junctions to improve air quality.
Nearby Broken Cross was declared an "air quality management area" by Cheshire East Council in 2017 due to high levels of nitrogen dioxide.
A council report said that while road alterations would improve air quality in the area, "the impacts of the development could be significantly worse than predicted".
Councillors approved three separate proposals for 398 homes on adjoining areas of land around Chelford Road to the west of Macclesfield, put forward by four different developers.
Local councillor Nick Mannion said traffic queues and air pollution would increase.
Macclesfield MP David Rutley wrote to councillors asking them to reject the applications until further work had been undertaken on "vital air quality issues".
Residents said they would consider launching a judicial review into the council's handling of the plans.
However, agent Gary Halman, representing the developers, said they rejected claims that air quality projections that had been produced for the plans had been "deliberately skewed".
He added: "The town needs new homes, especially affordable ones, for local families."
The council re-designated a number of green belt sites in 2017 as part of its local housing plan, which earmarked land for 36,000 new homes for more than 30 years.