Water quality by county
in Massachusetts
EPA sampled public water systems across Massachusetts for PFAS under its UCMR 5 programme. Of the 14 counties, 9 have a reading above a federal limit and 0 have not been sampled at all — which is not a clean result, only an absence of one. Each county below shows what was found, at what concentration, and at which utility.
| county | Population | Worst result | Compound |
|---|---|---|---|
| Bristol County | 588,593 | 23× | PFOA · 92 ng/L |
| Middlesex County | 1,668,956 | 9.3× | PFOS · 37.3 ng/L |
| Plymouth County | 542,090 | 8.8× | PFOS · 35 ng/L |
| Worcester County | 881,248 | 4.0× | PFOA · 15.8 ng/L |
| Norfolk County | 740,754 | 3.8× | PFOS · 15 ng/L |
| Essex County | 823,938 | 3.0× | PFOA · 12 ng/L |
| Barnstable County | 232,570 | 1.8× | PFOS · 7.1 ng/L |
| Hampshire County | 165,399 | 1.8× | PFOS · 7.1 ng/L |
| Berkshire County | 128,726 | 1.5× | PFOA · 5.9 ng/L |
| Franklin County | 70,871 | under the limit | PFNA · 4.8 ng/L |
| Dukes County | 21,061 | under the limit | — |
| Hampden County | 464,151 | under the limit | — |
| Nantucket County | 14,670 | under the limit | — |
| Suffolk County | 793,144 | under the limit | — |