# Total Trihalomethanes (TTHMs) — Drinking water contaminant limits by regulator

For Total Trihalomethanes (TTHMs), regulator is US EPA (National Primary Drinking Water Regulations); limit is 0.080; unit is mg/L; limit type is MCL (Maximum Contaminant Level), recorded from its source on 2026-08-06.

- **Contaminant:** Total Trihalomethanes (TTHMs) _(verified: appears in the quote below)_
- **Regulator:** US EPA (National Primary Drinking Water Regulations) _(our reading, not quoted from the source)_
- **Limit:** 0.080 _(verified: appears in the quote below)_
- **Unit:** mg/L
- **Limit type:** MCL (Maximum Contaminant Level) _(our reading, not quoted from the source)_

## What the source says

> Total Trihalomethanes ( TTHMs ) | n/a 6 | 0.080

## Source

- https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations

Last verified: 2026-08-06. Review by: 2027-08-06.
Part of [Drinking water contaminant limits by regulator](https://referencesource.org/drinking-water-contaminant-limits/).