The Environmental Protection Ministry is planning to declare Tel Aviv a city with polluted air - but the Tel Aviv municipality released data Sunday showing that the city's air quality has improved substantially.

Municipal officials are taking the ministry to task over plans to declare the city's air polluted, while the ministry cites data that the city has still fallen short of air quality targets.

The municipality's 2011 data reflect a sharp decline in concentration of air pollutants such as fine particulate matter and nitrogen oxide. These kinds of pollutants are the primary cause of respiratory, cardiac and circulatory problems among people exposed to it. The number of days in which air pollution exceeded the maximum standard at any of the city's monitoring stations declined over a 10-year period from 90 days per year to 19 days.

The Environmental Protection Ministry, however, cites 2010 data showing that Tel Aviv had high concentrations of nitrogen dioxide that year.

The municipality says improvements to air quality are the result of a long-term anti-pollution program - for example, the municipality has required gas stations in the city to sell fuel with lower levels of sulfur. The removal of the wholesale market from the city also improved air quality because it used to attract large numbers of heavily polluting diesel-powered trucks. And in an unrelated move, the Israel Electric Corporation switched the fuel it uses at the city's Reading power station from crude oil to natural gas, which is less polluting.

The municipality also cites other environmentally-friendly developments, such as bicycle rental stations, the expansion of the network of bicycle paths in the city and a 50-percent increase in green spaces over the course of a decade.

Despite the progress, the Environmental Protection Ministry plans on officially declaring Tel Aviv and several adjoining municipalities as polluted, which would give the ministry the power to order local authorities to take steps to address the problem.

"We don't understand why they have to declare Tel Aviv a polluted area when there is improvement and a plan that we are implementing. In my opinion, it would be inappropriate and unprofessional," said Moshe Blassenheim, who heads Tel Aviv's environment authority.

The Environmental Protection Ministry said the improvements to air quality in Tel Aviv were the result of action taken on a national level, stricter motor vehicle pollution standards and a government program designed to get old cars off the roads. "The ministry stands by its demand that [local] authorities in the Tel Aviv area advance plans to reduce air pollution," the ministry's statement said.

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