🧪 Formaldehyde in Water

Physicochemistry PN-71/C-04593

Overview

STATUS (as of 03.11.2026). PN-C-04593:1971 (former designation PN-71/C-04593) — Polish standard, Polish version, published on 06.11.1971, 3 pages, technical committee KT 122 (Water Quality — Chemical Testing — Organic Substances). THE STANDARD HAS BEEN WITHDRAWN — withdrawal date 13.12.2005 (PKN card); the card does not indicate a replacing standard. “Aldehyd mrówkowy” (formic aldehyde) is the old Polish name of formaldehyde.

SCOPE (PKN card). “The subject of the standard is a colorimetric method for determining the content of formic aldehyde (formaldehyde) in water and in waste water” (our translation).

FORMALDEHYDE IN WATER (WHO Guidelines for drinking-water quality, fourth edition incorporating the first and second addenda, formaldehyde fact sheet). Formaldehyde enters waters with industrial effluents, and in drinking water it results primarily from the oxidation of natural organic matter during ozonation and chlorination; concentrations of up to 30 µg/l have been found in ozonated drinking water, and it can also be released from polyacetal plastic fittings. WHO does not establish a guideline value for it, because in drinking water it occurs at concentrations well below those of health concern — the tolerable concentration for ingested formaldehyde is 2.6 mg/l. IARC classifies formaldehyde in group 1 (carcinogenic to humans), while according to WHO the weight of evidence indicates that it is not carcinogenic by the oral route. The regulation on water intended for human consumption (Dz.U. 2026 item 748) does not include formaldehyde in its list of parameters.

WHAT WE DO NOT GIVE HERE. The text of the standard is not freely available — the PKN catalogue shows only the card, and I did not find its content in repositories of standards or in the literature. Therefore we do not give the colour reagent, wavelength, measuring range, volumes, times or reaction conditions; the description of the reaction of formaldehyde with acetylacetone that was here before had no basis in the text of this standard. A laboratory applying this standard takes the procedure only from its text.

Method principle

According to the PKN catalogue card, the standard describes a colorimetric method for determining the content of formic aldehyde (formaldehyde) in water and in waste water. We do not give the reagent, wavelength or procedure, because the text of the standard is not publicly available.

Applications

• Water and waste water — scope of the standard according to the PKN card

Key parameters

Standard

Standard number

PN-C-04593:1971 (PN-71/C-04593)

Title (PL)

Woda i ścieki — Oznaczanie zawartości aldehydu mrówkowego

Title (EN)

Water and wastewater — Determination of formaldehyde content

Step-by-step procedure

1. Procedure according to the text of the standard

   The text of PN-C-04593:1971 is not publicly available — we do not give the steps, reagents or reaction conditions.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Formaldehyde — harmonised CLP classification: H302, H314 (causes severe skin burns and eye damage), H317, H330 (fatal if inhaled), H341, H350 (may cause cancer)

Frequently asked questions