PFAS above EPA’s limits in Puerto Rico.
The short answer
15 utilities serving 1.5 million people, as they report it, had a location averaging above a limit, most often PFOS (15) and Hazard Index (1). The largest is Metropolitano, whose highest PFOS average was 6.3 ppt, 1.6 times the limit. The furthest above is Aibonito la Plata, at 6.4 times the PFOS limit.
These are EPA’s survey results, not violations: the limits take effect April 26, 2029, and compliance will rest on each utility’s own monitoring. EPA has proposed changes to the rule; as of Oct. 13, 2026, none is final.
Utilities above a limit
Largest first. Each one’s highest location average is for the limit it is furthest above, with the single highest sample of the same PFAS; its report has every result.
| Utility | Based in | Serves | Above | Highest location average | Highest single sample |
|---|---|---|---|---|---|
| Metropolitano | Bayamon | 1,084,637 | PFOS | PFOS 6.3 ppt1.6 times the limit | 7.8 ppt |
| Aguadilla | Rincon | 124,782 | PFOS | PFOS 5.3 ppt1.3 times the limit | 5.3 ppt |
| Ponce Urbano | Penuelas | 113,972 | PFOS, PFHxS, Hazard Index | PFOS 25 ppt6.3 times the limit | 26 ppt |
| Santa Isabel Urbano | Santa Isabel | 39,925 | PFOS | PFOS 5.2 ppt1.3 times the limit | 10 ppt |
| Cidra Urbano | Cidra | 34,424 | PFOS | PFOS 7.7 ppt1.9 times the limit | 9.8 ppt |
| Patillas Urbano | Patillas | 32,222 | PFOS | PFOS 7.2 ppt1.8 times the limit | 14 ppt |
| Aibonito la Plata | Aibonito | 16,354 | PFOS | PFOS 26 ppt6.4 times the limit | 47 ppt |
| Manati East | Manati | 13,580 | PFOS | PFOS 4.6 ppt1.2 times the limit | 6.7 ppt |
| Las Bocas | Barranquitas | 11,022 | PFOS | PFOS 6.9 ppt1.7 times the limit | 7.2 ppt |
| Maunabo Urbano | Maunabo | 9,380 | PFOS | PFOS 4.4 ppt1.1 times the limit | 4.8 ppt |
| Salinas Urbano | Salinas | 8,977 | PFOS | PFOS 8.3 ppt2.1 times the limit | 9.6 ppt |
| Experimental | Juana Diaz | 6,445 | PFOA, PFOS | PFOA 17 ppt4.4 times the limit | 22 ppt |
| Aibonito Urbano | Aibonito | 5,580 | PFOS | PFOS 4.3 ppt1.07 times the limit | 4.3 ppt |
| Aruz | Juana Diaz | 5,105 | PFOS | PFOS 5.4 ppt1.4 times the limit | 7.1 ppt |
| Jacaguas | Juana Diaz | 4,261 | PFOS | PFOS 12 ppt3 times the limit | 12 ppt |
11 more utilities in Puerto Rico had a single sample above a limit but no location average above, so they are not listed; each report shows the sample.
Results: EPA UCMR 5 occurrence data, file of Oct. 15, 2026, samples from Jan. 3, 2023 to June 17, 2026, averaged by sampling location as EPA’s final UCMR 5 data summary does. Every state, and the full data as a CSV; how this list is made. People served is what each utility reports.
Where to go next
- Metropolitano’s reportEvery PFAS result with its dates, and the certification claim that handles each.Open the report
- Every stateThe national list, the largest utilities above a limit, and the data to download.PFAS above EPA’s limits
- Filters certified for PFASRanked by certification and what they cost over five years.Best water filters for PFAS