If the stench of San Jose's air during rush hour and the burning-eye sensation wasn't confirmation enough, authorities now acknowledge the city's air is unsafe to breathe.

In its fourth annual report on air quality, a coalition of government and university researchers published a scathing report on the state of the capital's air.

“This study succeeded in demonstrating that the high level of pollution is not just a threat to the environment but also to human health,” said José Luis Vargas, the Health Ministry's human environment protection director, during a presentation of the report yesterday.

The results showed nitrogen dioxide, the heavy metal manganese and particulate matter at levels above those recommended as relatively safe by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO).

Particulate matter can be solid or liquid and includes dust, soot, ash, cement and pollen. The smaller the matter is, the more dangerous it is because it can more easily penetrate a person's lungs and cause respiratory problems, aggravate asthma and cause infections, researcher José Rojas said.

Rojas and others from the National University (UNA) used 14 monitoring stations set up in the San José metropolitan area to collect data during 2007.

The heavy metal manganese, a neurotoxin, was reported at unsafe levels but the UNA report gave it short shrift and included no explanation of its potential health impacts.

“By inhalation, manganese has been known since the early 19th century to be toxic,” states a report on the WHO Web site. “Manganism (a result of exposure) is characterized by various psychiatric and movement disorders, with some general resemblance to Parkinson's disease. Respiratory effects such as pneumonitis and pneumonia and reproductive dysfunction such as reduced libido are also frequently reported features of manganese intoxication.”

Rojas' report blamed metal industries for this pollutant's presence.

Nitrogen dioxide levels were found to be consistently unsafe all year round in the downtown area as well as the Sabana Sur neighborhood. This chemical compound which can combine with sunlight to create ozone, causes skin irritation, damage to capillaries in the lungs, bronchitis and emphysema.

Particulate pollution was above safe levels during March, April, July, September and November.

UNA rector Olman Segura said the results show a failure of the nation's to deal with the problem.

“It's a danger for us to be above the (WHO) statistics,” he said. “It's a serious call to attention to review the country's policies and make the changes necessary. We have to create new policies, and it's only going to get worse if we don't act now.”

Energy and Environment Vice Minister Jorge Rodríguez said the Oscar Arias administration had “declared war” on pollution, but he offered no specifics on the policies of that war.

San José Mayor Johnny Araya said he was attacking the problem with proposals to plant more trees, coordinate San José bypass routes for commuters, increase train routes and create more pedestrian and bicycle-friendly areas.

Authorities said the pollution levels are not helped by the fact that the number of cars in the country is increasing by 8.45 percent each year.

“In 16 years, we already have 1.6 million vehicles in the country,” Araya said as he made a dig at Ticos who he said are copying the U.S. model of traffic and consumption.

“We don't need that North American model of organizing cities that serve the roads and shopping malls and not its citizens,” he said.

One of the recommendations in the report's conclusion was for the government's transportation, environment and health ministries to work together to come up with polices to diminish the pollution crisis.

No representative of the Transportation Ministry was in attendance.