Home » Preservatives » Potassium Nitrate (E252)

What is Potassium Nitrate (E252)?

Last updated on: 2/2/2026

Sources: WHO, US-FDA, EFSA, FSSAI.

5

/10

Moderate Concern

Safe within established ADIs, but high exposure is a concern. EFSA and WHO (JECFA) set a numerical ADI for nitrates, and EFSA concluded that dietary exposure may exceed the ADI, especially in children and infants, mainly due to total intake from food and water.

CTL SAFETY SCORE

A higher score reflects higher confidence in safety; it is based on regulatory approvals, intake limits, and individual sensitivities data.

Potassium nitrate is an inorganic salt used mainly as a preservative and curing agent. In foods—especially cured and processed meats—it serves as a source of nitrate, which can gradually convert to nitrite during curing. This helps control microbial growth, stabilise colour, and support flavour development. Nitrates also occur naturally in foods, particularly vegetables.

Safety Summary

Preservative and curing agent; acts as a nitrate source that can convert to nitrite during curing. Long history of use in food preservation, particularly meat curing, under strict regulatory control.

Who should be cautious?

EFSA identified children and infants as key sensitive groups due to potential ADI exceedance from total nitrate exposure.

Quick Facts

E-Number :

E252

INS Number :

INS 252

Category :

Preservatives

Sub-category :

Curing agent

Origin :

Synthetic (also naturally occurring in foods)

Used In :

Food

Alternative Names :

252 , Saltpeter

Similar Ingredients :

Sodium nitrate (E251), Sodium nitrite (E250), Potassium nitrite (E249)

Common Products

Cured meats (ham, bacon, sausages),Fermented and dried meat products,Certain preserved or cured meat preparations

Regulatory Approval.

1. Food and drug administration (fDA – USA)

Status
Usage Limit

Approved

Permitted curing agent with defined limits (21 CFR §172.160).

2. European Food Safety authority (eFSA)

Status
Usage Limit

Approved

Same ADI; exposure concerns for certain population groups (2017 re-evaluation).

3. Food safety and standardization authority India (FSSAI)

Status
Usage Limit

Approved

Permitted preservative (INS 252) with specified maximum limits.

Health concerns

EFSA reviewed toxicological, genotoxicity, sub-chronic, chronic, reproductive, and developmental data for nitrates.

Conclusions

Potassium nitrate (E252) is a regulated preservative and curing agent with an important technological role. While it is approved by FDA, EFSA, WHO/JECFA, and FSSAI, EFSA identified moderate concern due to potential ADI exceedance in infants and children from total dietary exposure. Careful regulation and controlled intake are essential to minimise risk.

Is potassium nitrate safe?
Yes, when used within regulatory limits. However, EFSA found that total dietary exposure can exceed the ADI, so intake control is important.

Who should be most cautious?
Infants and children, and people with high nitrate exposure from food or drinking water.

Why is potassium nitrate used in foods?
It supports controlled curing in meat products by acting as a nitrate source, helping with microbial safety and product stability.

Is potassium nitrate naturally present in foods?
Yes. Nitrates occur naturally in many vegetables and water; added nitrate is tightly regulated to manage total exposure.

How is potassium nitrate different from sodium nitrate?
They perform the same technological function; the difference is the counter-ion (potassium vs sodium). Both share the same ADI and similar regulatory controls.

References

Food And Drugs Administration (US FDA)

European Food Safety Authority (EFSA)

Food Safety And Standardization India (FSSAI)

WHO, Codex And Others