When we talk about PFAS, attention often focuses on water, because it is precisely through the contamination of groundwater and drinking water that these substances have caused some of the most serious environmental situations in recent years to emerge. But their fate in the environment could be more complex and also concern other matrices.
Now bringing attention to this aspect are new independent analyzes commissioned by the Rete Zero PFAS Italia, which have detected the presence of various PFAS in the dust collected in areas outside Legnago, in the province of Verona, and in Nuvolera, in the Brescia area.
The case of Legnago is particularly interesting because a Chemviron plant dedicated to the treatment of activated carbon used to remove PFAS operates in the municipal area. These materials, after being used in purification processes, must in turn be treated to manage the substances they have accumulated. It is precisely around this activity that the Rete Zero PFAS Italia wanted to concentrate part of its checks, trying to understand whether the presence of PFAS in the area could also be detected in the dust that settles outside.
For this reason, samples were collected at various points and sent to accredited laboratories for chemical analyses.
What was found in the dust
In Legnago the analyzes detected several perfluoroalkyl substances, including PFBA, PFHxA, PFHpA, PFOA and 6:2FTS, as well as other fluorinated compounds.
Among these there is therefore also PFOA, classified by the IARC as carcinogenic to humans. More generally, exposure to some PFAS has been associated in the scientific literature with various possible health effects, including alterations to the immune system and developmental problems, although not all substances in this large family have the same risk profile.
In the samples examined, the PFOA values reported by the Rete Zero PFAS Italia range from 11 to 54.1 micrograms per kilogram of dry matter (μg/kg).
In Nuvolera, however, high concentrations of some other fluorinated compounds were detected in the dust collected on the balconies. In particular, the analyzes report 28.4 μg/kg of 6:2FTOH, 148.8 μg/kg of PFBA and 1069.6 μg/kg of 8:2FTOH, compounds that the Network indicates among those that deserve further investigation.
To understand the extent of these substances and the caution they require, it should be remembered that the European Food Safety Authority (EFSA) has established an extremely severe tolerable weekly dose for the sum of the four main PFAS: just 4.4 nanograms per kilogram of body weight. Translated into concrete figures, the maximum recommended intake limit per week is just 264 ng for a 60 kg adult and just 88 ng for a 20 kg child.
They are parameters that demonstrate how these molecules can act at infinitesimal doses, but which refer to intake through water and food and cannot be automatically interpreted as a measure of risk for environmental dust. For the latter, in fact, there is no official limit value that allows us to establish whether a given concentration is safe or dangerous for the population.
As the Zero PFAS Network writes:
To date, there are no limits for the release of PFAS into the air because no European public body has developed them. This is not to say that PFAS in the air are not dangerous.
@Rete Zero PFAS
Where do they come from?
This is the real crux of the story. If PFAS are found in the dust that settles outside, it is necessary to understand what their origin is and through what path they ended up in the environment. The finger is obviously pointed towards the industrial activities present in the areas concerned, but the available data does not currently allow a direct connection to be established.
In Legnago, in particular, the attention of the Rete Zero PFAS Italia is also focused on the possible atmospheric emissions of the plant that treats the activated carbon used to remove PFAS. According to the Network, specific controls on emissions and more in-depth monitoring of the area would have been required in the past.
However, it is important to distinguish between a hypothesis to be verified and a responsibility that has already been established. The analyzes commissioned by the Network are in fact independent and, as the organization itself underlines, do not replace the checks carried out by public bodies. Precisely for this reason, the authorities are asked to carry out further sampling and joint analyses, using shared methodologies, to understand whether the presence of PFAS in the dust is confirmed and, above all, what its origin is.
PFAS in the air
The presence of PFAS in dust raises a crucial question: are these substances also present in the air? The analyzes of the Rete Zero PFAS Italia cannot alone answer this question, but represent a first element to be explored in greater depth. Also because, as the Network underlines, there are currently no specific European limits for the release of PFAS into the air.
For this reason, the association calls for broader environmental controls and monitoring, which allow us to verify the presence of PFAS in the air and dust and above all to understand where they come from. In Legnago, in particular, this also means examining the possible role of the industrial activities present in the area and verifying with official sampling what emerged from the independent analyses.
