Figures reveal Glasgow's Hope Street is one of the most polluted streets in Scotland.
Environmental campaigners Friends of the Earth Scotland analysed data which it said looked at the country's dirtiest streets.
And it turns out Hope Street was found to have 65 microgrammes of nitrogen dioxide per cubic metre, breaking the European directive of 40.
Also making the list were Cambuslang Main Street with 45 g/m3 of nitrogen dioxide, and Glasgow's Dumbarton Road.
Official figures for two toxic pollutants reveal air quality safety standards are regularly broken, the campaign group said.
In 2016 new official pollution zones were declared in Linlithgow and Newton in West Lothian, Johnstone and Renfrew in Renfrewshire, and with Edinburgh's Salamander Street coming into force later this month, taking the number up to 38 across the country.
Jean Nelson, 59, from Glasgow, believes pollution has contributed to her chronic obstructive pulmonary disease.
She said: "I live at a junction where the traffic is nose to tail almost every minute of the day, and I feel like I'm choking on fumes on a daily basis.
"Air pollution makes it hard for me to breathe and on bad days, I can barely walk. I do not own a car and often have to take the bus from Hope Street. I can see black smoke coming out of the buses and sometimes am forced to take a taxi just to escape the fumes.
"We need less traffic on our roads if air pollution is going to improve. There are thousands more cars on the roads every year and the problem is only getting worse."
Friends of the Earth Scotland said the Scottish Government needs to take the issue more seriously.
Air pollution campaigner Emilia Hanna said: "Air pollution from traffic is a public health crisis, claiming thousands of lives each year and particularly harmful for small children, pregnant women and people living in poverty.
"For people living in an official pollution zone or near traffic-choked streets, breathing in toxic air is an inescapable fact of life. It should not be this way, we have the right to breathe clean air just as we have the right to drink clean water.
"The Scottish Government and local authorities are not tackling this public health crisis with the seriousness and urgency required.
"We now have a staggering 38 official pollution zones across Scotland, up from 33 last year. This means that many more people are living with illegal levels of air pollution than previously recognised.
"The Scottish Government has promised a 'plan' for Low Emission Zones by 2018 but needs to make a public commitment that it will provide significant funding, so that local councils can get on with making serious plans to clean up the air in their area."