A production that stops, after years of controversy, controls and requests for greater environmental protection. On 28 October 2026, Syensqo, the company born from the separation of Solvay’s chemical activities, announced the cessation of C6O4 production at the Spinetta Marengo plant, in the province of Alessandria. It is a substance belonging to the PFAS family, used as an aid in the production of some fluoropolymers.
The decision comes ahead of the December 31, 2026 deadline set by the plant’s Integrated Environmental Authorization (AIA) renewal procedure. An important step, which the company attributes to the development of a new production technology without fluorosurfactants.
The news, however, must be read in its context. Because the chemical center of Spinetta Marengo has long been at the center of concerns due to the presence of pollutants in the groundwater and in the surrounding environment. And stopping C6O4 production does not mean that PFAS have disappeared from the site or that the cleanup is complete.
Because there is so much talk about Spinetta Marengo
For those who don’t know them yet, PFAS, an acronym for per- and polyfluoroalkyl substances, are a vast family of chemical compounds used in numerous industrial processes and commonly used products. Their link with environmental contamination also depends on the difficulty with which many of these substances degrade, which is why some are known as persistent pollutants and can accumulate in the environment.
Spinetta Marengo, a hamlet in the municipality of Alessandria, is home to a historic chemical hub in which various properties and production activities have followed one another over time. Today the processes are largely linked to the chemistry of fluorinated compounds.
The focus on this site is not just about C6O4. Environmental investigations have detected several PFAS over time, including PFOA, cC6O4 and ADV, as well as other contaminants of industrial origin. In March 2019 Arpa Piemonte started monitoring PFAS in groundwater after finding their presence during its own investigations.
The checks highlighted a complex situation, which does not end with the production of a single substance. According to the data reported in the regional environmental framework, the contamination mainly affects some areas inside the chemical hub, but fluorinated substances were also detected in the surface water table outside the plant, along the direction of its flow.
Over the years, the affair has attracted the attention of institutions, technicians and citizens, fueling the demand for more stringent controls on emissions and effective interventions to deal with contamination. In fact, the topic concerns not only the substances used in production cycles, but also what can be released into the environment and the management of the consequences of industrial activities carried out over time.
C6O4, what changes with the stop announced by Syensqo
C6O4 is a fluorinated compound used as an aid in the polymerization process to produce some fluoropolymers. These materials find use in specialized industrial applications, including semiconductors, batteries and hydrogen-related technologies.
In its press release, Syensqo explains that the investments in research and innovation launched since 2019 have made it possible to develop an alternative technology that does not require the use of fluorosurfactants. The company claims that almost 100% of its fluoropolymers are now produced without these process aids and that this development has made it possible to stop the production of C6O4 at Spinetta Marengo.
However, there remains a residual portion of processes for which, according to the company, an adequate technological alternative is not yet available. This is approximately 1% of the volumes of finished products: for these productions, the C6O4 stocks already present in the plant will be used, while work will continue to switch to a technology without fluorosurfactants.
The company’s decision therefore anticipates a deadline that had already been set by the authorities. On 5 August 2026, at the end of the Services Conference for the renewal of the Integrated Environmental Authorization (AIA), the Province of Alessandria, the Municipality, Arpa Piemonte and ASL AL announced new environmental requirements for the plant. Among these, the ban on producing cC6O4 starting from 1 January 2027 and the possibility of using exclusively the residual quantities already present on the site to create two products, equal to approximately 1% of the total volumes of finished product. These processes too will eventually have to switch to an alternative technology without fluorosurfactants
The new measure also provides specific limits for PFAS emissions into the atmosphere, with a progressive reduction in subsequent years. It is an important aspect because environmental protection does not only depend on ceasing the production of a substance, but also on the control of emissions and compliance with the requirements for plants.
Stopping production does not erase the contamination
The end of C6O4 production represents a concrete change in the industrial process of the plant, but it certainly does not equate to the resolution of all of Spinetta Marengo’s environmental problems.
Arpa Piemonte’s monitoring for 2025 confirmed the presence of PFAS in groundwater, both inside the chemical center and outside, along the direction of flow of the aquifer. The Agency also detected the presence of these substances in the air through monitoring of airborne particulates in the area, stating that there are currently no regulatory limits available for PFAS in ambient air with which to compare the results.
These are data that help to distinguish two issues: on the one hand the reduction in the use of fluorinated substances in production processes, on the other the contamination already present and the need to address it with controls, interventions and checks over time.
Syensqo’s announcement therefore marks a step forward in the replacement of fluorosurfactants, but does not close the story of the Alexandrian chemical hub. The challenge remains to verify the actual reduction of emissions, follow the evolution of water and air quality and ensure that the measures envisaged by the authorities produce concrete environmental results.
The reaction of the Stop Solvay Committee
Syensqo’s decision is welcomed with satisfaction, but without lowering one’s guard, by the committees and associations that have been fighting against the contamination of Spinetta Marengo for years.
The No PFAS Committee is keen to underline that the result is not only the result of technological innovation, as underlined by the company, but also of the pressure exerted over the years by citizens and activists through complaints, public initiatives and requests to institutions. In fact, he writes in a post on Facebook:
If we have achieved this result today, it is thanks to those who have reported for years, organized initiatives, collected information and forced companies and institutions to deal with what is happening in Spinetta.
As committees and associations we have never stopped asking for contamination to be accounted for, we have continued to bring the problem to the streets and to the institutions.
Today we also claim the result of this work, without forgetting how much it cost to get there and how many years were lost.
Today we are aware that pressure from below can have an impact and that we cannot stop until the territory and public health are truly protected.
The cessation of C6O4 production, however, they underline, does not solve the problem of PFAS already dispersed in the environment. The requests remain a stop to the production and use of all these substances, the complete remediation of the area, inside and outside the plant, and greater transparency on emissions and possible health effects.
We will not stop because production ceases. We will stop when all PFAS runs out and cleanup is a reality.
