Lisbon, April 15, 2026 (Lusa) - Portugal's national meteorological institute (IPMA) president, José Guerreiro, has refuted claims linking alleged food poisoning cases abroad to clams harvested from the legally exploitable zone of the River Tagus.
He addressed a parliamentary hearing on Tuesday, which had been convened following requests from the PS (Portugal’s Socialist Party) and the PSD (Portugal’s Social Democratic Party).
The PS had called for the session to discuss the scandal involving contaminated clams from the Tagus estuary, while the PSD sought to address the ongoing illegal harvesting of Japanese clams in the same area.
The IPMA is the National Reference Laboratory for Marine Living Resources, responsible for identifying areas open to harvesting, monitoring them, and declaring whether they remain suitable for harvesting.
He said that a report he had requested from the national health authority (DGS) showed only seven confirmed cases of E. coli (a type of bacteria commonly found in the intestines of humans and warm-blooded animals) between January 2023 and July 2025, adding that none of those cases had been explicitly linked to the consumption of bivalves, specifically the Japanese carpet shell clam from the Tagus.
"Therefore, the reports that have come to light regarding Portugal are unfounded; they have no basis in the national health authority’s findings, and the cause-and-effect relationship between these factors, which requires a very clear explanation, remains to be proven," he said, adding that there was a distinction between clams harvested in duly licenced areas, in zones designated for harvesting, and illegal fishing.
He added that there were two areas in the Tagus estuary: one upstream of the Vasco da Gama Bridge and the other downstream.
Only the downstream zone was legally exploitable, and even then, the catch required purification before being fit for consumption.
During the session, PS MP for the Setúbal Constituency, António Mendonça Mendes, said that reports that 348 people across Europe had required hospital treatment after eating bivalves allegedly caught illegally in the Tagus triggered the hearing, highlighting the importance of identifying any potential failures in the national sanitary monitoring system.
Guerreiro also emphasised the importance of distinguishing between legal, properly licensed fishing in the Tagus estuary and what had allegedly been illegal and unlicensed fishing.
He said that the monitoring system, which conducts regular weekly, fortnightly, and monthly analyses, remained robust and had never been compromised, adding that there was no serious non-compliance within the system.
“Therefore, these cases that allegedly occurred abroad have not been shown anywhere to have originated from what would be the legally exploitable zone.”
“And so, this is a non-issue, in terms of the Bivalve Control and Monitoring System,” he said.
In January, the Directorate-General for Marine Resources (DGRM) banned the harvesting of Japanese clams through an order issued on 22 January 2026, which revoked the licences issued for 2026 to combat illegal fishing and harvesting of these bivalve molluscs in various parts of Portugal.
Tuesday's hearing also heard evidence from the DGRM Director-General, the Food and Economic Safety Authority (ASAE) Inspector-General, the Maritime Authority Director-General, the Maritime Police Commander, the CEO of Docapesca - Portos e Lotas, S.A., and the Regional Director of Nature Conservation and Forests for Lisbon and the Tagus Valley.
GC/MYAL // ADB.
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