# The Water Contaminants Worth Testing For (2026)

> Priority water analytes by risk context: lead, arsenic, nitrate, PFAS, bacteria on wells, disinfection byproducts—test before you filter-shop.

*Published 2026-07-10 · Updated 2026-07-10 · By Elena Voss*

*Medical disclaimer:* Environmental-health editorial—not laboratory medical advice or a substitute for certified lab interpretation and local health department guidance.

The short answer

Match tests to risk: **lead**, **arsenic**, **nitrate**, **PFAS**, microbes on wells. Start with [EPA private well resources](https://www.epa.gov/privatewells) and our [water filtration guide](https://healthcanon.com/environmental-health/water-filtration-reverse-osmosis-guide).

This roundup ranks analytes—not mystery wellness water panels sold without context.

## How to sequence testing

Read utility reports if on a public system; design a well panel if private; then choose treatment that matches detections.

## Sources

1. [EPA private drinking water wells](https://www.epa.gov/privatewells)
2. [Safe Drinking Water Act hub](https://www.epa.gov/sdwa)
3. [CDC private wells](https://www.cdc.gov/healthywater/drinking/private/wells/index.html)

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Source: https://healthcanon.com/environmental-health/best-water-contaminants-to-test-2026
Index: https://healthcanon.com/llms.txt · Full text: https://healthcanon.com/llms-full.txt