Thirty monitoring stations throughout Sardinia and a constant danger : polluting gases and fine dust . The former mark the pace in the industrial areas of the island and are released precisely from the production processes; the latter, starting with the more famous Pm10, are mainly generated by the combustion of fuels. In both cases, their presence becomes harmful when the concentration exceeds certain limits , set by law, and lasts over time.
MONITORING - A premise is needed to accompany the Sardinian map on air quality : monitoring is daily and is part of national and European protocols. The data is sifted by Arpas, the regional environmental agency. The system is computerized. The big brain is in Cagliari, in the offices in via Carloforte 51. There is the Cot, the operational center for acquisition of surveys. The numbers arrive from the control units located in the territories and are transferred to Sira, the regional environmental information system.
The via Cadello station in Cagliari is a garrison of the metropolitan city together with the stations of via Sant'Angelo in Monserrato and via Perdalonga in Quartu. There, the red lights come on a couple of times a month, as can be seen from the reports published on the SardegnaArpa website. Suffice it to say that in the capital and surrounding areas there are 419,399 residents (January 2023 data). Add to this the inhabitants not registered in the local registers and the commuters who gravitate to the vast area of Cagliari every day for the most varied reasons. We are talking about almost a third of the Sardinian population , who mainly travel by their own means.
ILLNESS RISK – Pm10s are called this because the particulate matter has a size equal to or less than 10 microns , or ten thousandths of a millimetre. These are dusts that are not visible to the naked eye and that the human body is able to neutralize through the filter of the nose, trachea and bronchi. To make them harmless. Problems arise when the PM10 concentration exceeds 50 micrograms per cubic meter and this occurs for more than 35 days a year . In these cases the respiratory system suffers. It means risk of diseases, infections and tumors.
Since January, PM10s have also exceeded warning levels in the streets of Olbia : in the capital of Gallura, the detection center is in via Fausto Noce, one of the local mobility hubs. Another PM10 "hot area" is the urban area of Sassari : here the danger level is exceeded through the via Budapest station. From time to time, the PM10 concentration exceeds 50 micrograms per cubic meter in Sulcis too: the detection passes from the plant in Nuraxi Figus, a hamlet of Gonnesa, crossed by a provincial road which is a local traffic hub. Moreover, fine dust, in addition to being released by the combustion of fuel, is also generated through the wear of tyres, clutches and brakes.
In 2023, however, PM10 never went beyond the threshold in the rural areas of Sardinia , another piece of monitoring, as foreseen by the Regional Air Quality Plan. In this case the control units are located in Carbonia in Sulcis, in Nuraminis in Southern Sardinia and in Santa Giusta in the Oristano area. Then here are the stations of Siniscola, Alghero and Seulo. Finally, the Macomer and Ottana control units, where the PM10s detected in 2023 have always remained below warning levels.
INDUSTRIAL AREAS – Industrial zones aside: the regional air quality plan monitors the sites of Assemini-Macchiareddu, Sarroch, Portoscuso and Porto Torres . Here since January the emergency has been double: the threat did not come only from particulate matter, but also the non-standard detections of some gases harmful to the environment.
Arpas data from July shows that fine particles have exceeded the limit of 50 micrograms per cubic meter in both Assemini and Porto Torres . In the first case the detection started from the control unit of Strada Consortile 3; in the second case the alarm came from the via Pertini station. Exceeding the Pm10 limits also in Portoscuso , again in July: the detection systems located in via Dante and Primo Maggio act as a warning. The other episodes can be obtained from the October 2023 report, also online on Sardegna Ambiente: fine particles have once again triggered the alert in Sulcis and again in the industrial center of Northern Sardinia .
In April, however, record levels of sulfur dioxide were recorded in the industrial area of Assemini-Macchiareddu. «There were three exceedances of the hourly average – it is written in the Arpas documents – with a maximum value of 452 micrograms per cubic meter». The legislation sets the limit at 350 micrograms. Sulfur dioxide, also called sulfur dioxide, is the major sulfur-based air pollutant and can be irritating to the respiratory tract.
No less severe are the effects deriving from the high concentration of ozone , as recorded on several occasions in the production centers of Sardinia monitored by the regional Agency. Two episodes date back to last July. «Several exceedances of the eight-hour moving average have been detected» in the stations of Sarroch , «in via della Concordia and in via Rossini», it is written in the monthly reports. The same happened in Portoscuso , as transferred by the Arpas switchboard from the Via Primo Maggio station. The limit exceeded was 120 micrograms per cubic meter. In the Sulcis center it happened "twice", according to the online reports.
Again: in September the quantity of ozone present in the air exceeded "the eight-hour moving average" in the consortium Dorsale of Macchiareddu . In Sarroch, in the same month, there were five gas peaks, one outside the threshold again detected by the control unit in Via della Concordia. Where there have already been "several exceedances" this month of October, the control unit in via Rossini recorded.
Ozone is monitored because its excessive presence in the air is harmful to the health of people and animals: the acute effects lead to irritation of the eyes, nose, throat and respiratory system. However, none of the Arpas reports indicates the abnormal value reached in recent months.
From the national protocols we derive only one certainty: we speak of an "alarm threshold" when the presence of ozone in the air is equal to or greater than 240 micrograms per cubic meter.
