Address data taken as part of a ZIP Code project studying smoking habits in Milwaukee has revealed 42 per cent of people in the city's poorest neighborhoods smoke.
This figure is twice the national US average and largely accounts for households on incomes of less than $15,000 a year, reports ScoutNews.
Bruce Christiansen, an associate scientist with the University of Wisconsin Center for Tobacco Research and Intervention in Madison, said the national smoking rate has fallen in recent decades, but this is primarily among people with better education and higher wage brackets.
Dr Jay Brooks, chairman of hematology and oncology at Ochsner Health System in New Orleans, told the news agency: "Smoking tends to be a disease of poverty and lack of education. Thirty years ago, 50 per cent of the population smoked and now we're down to roughly 25 per cent."
ZIP Code software will be used to provide details of schools in the Chicago suburbs where children will be able to get vaccinations against swine flu, according to the Daily Herald.