PFAS in tap water: Miyagi Prefecture
In Miyagi Prefecture’s water supplies, the highest combined PFOS and PFOA value for FY2020–FY2025 (FY2025 through the end of August) was 13 ng/L in Tagajo City (多賀城市) (FY2021). Tagajo City has been nd (below the detection or quantification limit) since FY2022. The prefecture’s maximum in FY2024 was 4 at the Misato Town water utility (美里町水道事業), and in FY2025 it was 2, also at Misato Town.
Levels by utility (PFOS + PFOA combined, ng/L)
| Utility | FY2020 | FY2021 | FY2022 | FY2023 | FY2024 | FY2025* | Sampled at |
|---|---|---|---|---|---|---|---|
| 村田町水道事業Water supply · 村田町buys all its water — Buys from 仙南・仙塩広域水道用水供給事業 | — | — | — | — | — | — | — |
| 角田市水道事業Water supply · 角田市 | nd | nd | nd | nd | nd | nd | raw water only |
| 丸森町水道事業Water supply · 丸森町 | — | — | — | — | nd | nd | plant outlet and raw |
| 七ヶ浜町水道事業Water supply · 七ヶ浜町buys all its water — Buys from 仙南・仙塩広域水道用水供給事業 | — | — | — | — | — | nd | — |
| 女川町水道事業Water supply · 女川町 | — | — | — | nd | — | — | tap only |
| 松島町水道事業Water supply · 松島町 | — | — | — | nd | nd | — | plant outlet and raw |
| 白石市水道事業Water supply · 白石市 | — | — | — | nd | — | — | tap only |
| 色麻町水道事業Water supply · 色麻町 | — | — | — | — | nd | nd | raw water only |
| 蔵王町水道事業Water supply · 蔵王町 | — | — | — | — | 3 | nd | raw water only |
| 加美町水道事業Water supply · 加美町 | nd | 4 | nd | nd | nd | — | tap and raw |
| 南三陸町水道事業Water supply · 南三陸町 | — | nd | nd | nd | nd | — | tap and raw |
| 大河原町水道事業Water supply · 大河原町 | — | nd | nd | 5 | nd | — | plant outlet only |
| 涌谷町水道事業Water supply · 涌谷町 | — | — | — | 6 | nd | nd | plant outlet only |
| 富谷市水道事業Water supply · 富谷市buys all its water — Buys from 仙南・仙塩広域水道用水供給事業, 大崎広域水道用水供給事業 | — | — | — | — | — | nd | — |
| 美里町水道事業Water supply · 美里町 | — | nd | nd | 3 | 4 | 2 | plant outlet only |
| 大和町水道事業Water supply · 大和町 | — | — | — | — | nd | — | — |
| 大郷町水道事業Water supply · 大郷町 | — | — | — | — | nd | nd | tap, plant outlet and raw |
| 亘理町水道事業Water supply · 亘理町 | nd | nd | nd | nd | nd | nd | raw water only |
| 山元町水道事業Water supply · 山元町 | — | — | — | — | nd | — | tap and raw |
| 川崎町水道事業Water supply · 川崎町 | — | — | — | — | nd | — | plant outlet only |
| 利府町水道事業Water supply · 利府町 | nd | nd | nd | nd | nd | — | plant outlet and raw |
| 仙台市水道事業Water supply · 仙台市Also buys from: 仙南・仙塩広域水道用水供給事業 | nd | nd | nd | nd | nd | nd | plant outlet and raw |
| 気仙沼市水道事業Water supply · 気仙沼市 | — | nd | nd | nd | nd | nd | tap only |
| 石巻地方広域水道企業団Water supply | — | 4 | 5 | 3 | 2 | nd | plant outlet and raw |
| 塩竈市上下水道部Water supply · 塩竈市 | nd | nd | nd | nd | nd | nd | — |
| 登米市水道事業Water supply · 登米市 | — | nd | nd | nd | nd | nd | plant outlet and raw |
| 岩沼市水道事業Water supply · 岩沼市 | nd | nd | nd | nd | nd | nd | plant outlet and raw |
| 多賀城市Water supply · 多賀城市buys all its water — Buys from 仙南・仙塩広域水道用水供給事業 | — | 13 | nd | nd | nd | nd | tap and raw |
| 柴田町水道事業Water supply · 柴田町buys all its water — Buys from 仙南・仙塩広域水道用水供給事業 | — | nd | nd | nd | — | — | tap only |
| 大衡村水道事業Water supply · 大衡村buys all its water — Buys from 大崎広域水道用水供給事業 | — | — | — | — | — | — | — |
| 栗原市水道事業Water supply · 栗原市 | nd | nd | nd | nd | nd | nd | tap, plant outlet and raw |
| 名取市水道事業Water supply · 名取市 | nd | nd | nd | nd | nd | nd | plant outlet only |
| 大崎市上下水道部Water supply · 大崎市 | nd | nd | nd | nd | nd | nd | tap and raw |
| 仙南・仙塩広域水道用水供給事業Bulk supplierSupplies: 白石市、角田市、岩沼市、蔵王町、大河原町、村田町、柴田町、亘理町、山元町、仙台市、塩竈市、名取市、多賀城市、富谷市、松島町、七ヶ浜町、利府町 | nd | nd | nd | nd | nd | nd | plant outlet and raw |
| 大崎広域水道用水供給事業Bulk supplierSupplies: 大崎市、栗原市、加美町、涌谷町、美里町、大郷町、松島町、富谷市、大衡村、大和町 | nd | nd | nd | nd | nd | nd | plant outlet and raw |
| 気仙沼市八瀬簡易水道事業Small water supply · 気仙沼市 | — | nd | nd | nd | nd | nd | tap only |
| 気仙沼市廿一簡易水道事業Small water supply · 気仙沼市 | — | — | — | — | nd | nd | tap only |
| 蔵王町北原尾簡易水道事業Small water supply · 蔵王町 | — | — | — | — | nd | nd | raw water only |
| 七ヶ宿町簡易水道事業Small water supply · 七ヶ宿町 | — | — | — | — | nd | nd | raw water only |
| 小里簡易水道組合Small water supply | — | — | — | — | nd | — | tap only |
These are the highest values in each fiscal year reported by each utility to the national government (MLIT and the Ministry of the Environment). A utility with several sources or treatment plants can have different levels in different parts of its area. Samples are taken at the tap in principle, but some utilities only measured raw water (water before treatment), and raw-water values are not covered by the tap-water standard. nd = below the detection or quantification limit; — = no value reported. *FY2025 covers results up to the end of August 2025. Utility names are left in Japanese as in the official table.
>50 a year above 50 ng/L (for utilities that also sampled raw water, the value may be from raw water) raw above 50 ng/L, but measured in raw water only
Good to know
- The Sendai City water utility (仙台市水道事業) and the bulk water suppliers (utilities that sell water wholesale to cities and towns) Sennan-Senen Regional Water Supply (仙南・仙塩広域水道) and Osaki Regional Water Supply (大崎広域水道) were nd for all six years.
- Six utilities buy all their water from a bulk supplier (they buy water from another utility). Tagajo City also buys all its water as of August 2025. Check the values of the supplier as well. → How to read the national table
- Private water supplies (for a facility) were tested at 54 of the 88 operators, and no exceedance of the provisional target value has been confirmed (through the end of August 2025).
Put it in terms of your own intake
- Intake from water
- — ng/kg/day
- Compared with Japan’s tolerable daily intake (PFOS and PFOA, 20 ng/kg bw/day each)
- —
- Compared with EFSA’s tolerable weekly intake (4 PFAS combined, 4.4 ng/kg bw/week ≈ 0.63 a day)
- —
- Compared with intake from 37 foods (MAFF estimate: PFOS 0.13 + PFOA 0.09 = 0.22 ng/kg bw/day; the 37 foods make up about half of what people eat by amount)
- —
The combined value is treated as a single substance (in reality it is split between PFOS and PFOA, so the share of Japan’s TDI would be smaller). EFSA’s value is for the sum of PFOA, PFNA, PFHxS and PFOS; tap-water values here do not include PFNA or PFHxS. This calculation shows how the same intake reads differently against different yardsticks; it does not judge health effects.
Related explainers
Sources
- Ministry of the Environment and MLIT, “Results of the follow-up survey on PFOS and PFOA in water supplies” (December 25, 2025)
- Same, list of survey results (updated), Excel (annual maximums, FY2020–FY2025)
- Same, follow-up survey annex (status of private water supplies by prefecture)
Last checked 2026.10.04 (against the original government documents and papers, collected and cross-checked in Gemini Notebook). Utility values are as in the national table; Urayomi sorted and summarized them.