Nitrosamines

NDMA in the bedroom

NDMA — N-nitrosodimethylamine — is a small nitrosamine that is, by mass, one of the most potent carcinogens known. It is the compound whose trace contamination triggered worldwide recalls of the heartburn drug ranitidine and several blood-pressure medicines. In the home it is not stored in a product; it forms — when chlorine-based cleaning chemistry meets the amine residues left by skin, food, and consumer products — and it occurs in the residue of tobacco smoke.

This page covers what NDMA is, the two pathways that put it in a bedroom, and what reduces it. It is a compound where the honest answer is that the formation chemistry is well-understood but in-bedroom concentrations are not well-measured.

NDMA — Embr Bedroom Chemistry Atlas

At a glance

Chemical familyNitrosamine — N-nitroso compound; the smallest dialkylnitrosamine, (CH₃)₂N–N=O
CAS number62-75-9
ClassificationIARC Group 2A (probably carcinogenic to humans); NTP Report on Carcinogens — reasonably anticipated to be a human carcinogen; EPA IRIS — B2 probable human carcinogen with a very potent cancer slope factor; regulated in drinking water at nanogram-per-litre levels
Where you encounter itFormed in situ from secondary amines plus nitrosating agents (nitrite, chloramine, hypochlorite); thirdhand tobacco smoke; cured and nitrite-preserved foods; trace contaminant of some rubber products and, historically, certain pharmaceuticals
Sleep micro-environment relevanceTwo pathways: chlorine-based cleaning products reacting with amine residues on bedroom surfaces, and nitrosamine residue from thirdhand smoke. In-bedroom air concentrations have not been well characterised
Activated carbon captureModerate — adsorbs onto activated carbon, but its small size and water solubility limit capacity, and low-concentration breakthrough is documented in water treatment

Regulatory & certification status

Where NDMA stands across the major regulatory systems and the certifications a bedroom product might carry. Each row links to the governing instrument; where a jurisdiction has no specific measure, that is stated plainly rather than left blank.

European UnionHarmonised CLP classification confirmed (Regulation 1272/2008, Annex VI, Index No. 612-077-00-3): Carcinogen Category 1B (H350 – may cause cancer), Acute Tox. 2 by inhalation (H330 – fatal if inhaled), Acute Tox. 3 oral (H301 – toxic if swallowed), STOT RE 1 (H372), and Aquatic Chronic 2 (H411). Not identified on the REACH SVHC Candidate List or the Authorisation List (Annex XIV). Separately, EU law caps N-nitrosamine/N-nitrosatable-substance release from rubber or elastomer teats and soothers at 0.01 mg/kg (nitrosamines) and 0.1 mg/kg (nitrosatable substances) — originally Commission Directive 93/11/EEC — with an equivalent nitrosamine restriction applied to toys for under-3s and other mouth-contact toys under the Toy Safety Directive (2009/48/EC, tested to EN 71-12). This is a narrow childcare/toy-article rule, not a general restriction on bedding or consumer products. Regulatory — EUR-Lex · EDQM Safety Data Sheet (N-
United StatesNo current EPA TSCA risk evaluation or high-priority-substance designation: NDMA was on the TSCA Work Plan for Chemical Assessments from 2012 until EPA removed it in the 2014 update, specifically because it "no longer present[s] exposure potential from current consumer or commercial use"; it does not appear on either subsequent High-Priority Substance list (the 20 chemicals designated in 2019 or the 5 designated in 2024). It is not manufactured for commercial use in the United States and occurs mainly as an unintentional byproduct (e.g., of drinking-water/wastewater chlorination) — a legacy/incidental substance rather than a produced chemical. EPA's IRIS program separately classifies it Group B2, a probable human carcinogen, based on animal tumor data at multiple sites; this is a hazard assessment, not itself a TSCA restriction. It is listed under California Proposition 65 as a carcinogen (listed October 1, 1987), with a No Significant Risk Level of 0.04 µg/day. Regulatory — OEHHA · US EPA IRIS
CanadaFinal-listed on CEPA Schedule 1 (List of Toxic Substances) since May 15, 2003, following a Priority Substances List assessment whose public comment period ran February 19 – April 19, 2000 and which concluded: "NDMA is considered to be 'toxic' as defined in Section 64 of CEPA 1999." It remains listed today and is carried into the current Prohibition of Certain Toxic Substances Regulations. There are no current industrial or commercial uses of NDMA in Canada; it occurs mainly as a byproduct of manufacturing (pesticides, rubber tires, alkylamines, dyes) and municipal wastewater treatment. Regulatory — Government of Canada
AustraliaNo AICIS-specific restriction or assessment identified for NDMA as an industrial chemical (searched AICIS's chemical information resources directly; no scheduling, assessment, or restriction entry found). Separately, Australia does set a drinking-water guideline value for NDMA (0.0001 mg/L / 100 ng/L) via the NHMRC Australian Drinking Water Guidelines, but that is a water-quality guideline, not an industrial-chemical or consumer-product restriction, so it does not change the "not found" status for AICIS purposes. Regulatory — AICIS · NHMRC
United KingdomConfirmed on the UK's GB Mandatory Classification and Labelling list (GB MCL List), which carries the same Index No. 612-077-00-3 entry onshored from EU CLP Annex VI as retained law after Brexit: Carcinogen Category 1B (H350), Acute Tox. 2 by inhalation (H330), Acute Tox. 3 oral (H301), STOT RE 1 (H372), Aquatic Chronic 2 (H411) — identical to the EU harmonised classification. It is not on the UK REACH Candidate List, which only carried over substances already on the EU SVHC Candidate List at the end of the transition period (NDMA was not among them). Regulatory — HSE
InternationalIARC classifies N-Nitrosodimethylamine as Group 2A, "probably carcinogenic to humans" (Volume 17, 1978; overall evaluation upgraded to Group 2A with supporting evidence from other relevant data, Supplement 7, 1987) — confirmed verbatim as its current entry on IARC's official master classification list (CAS 62-75-9: Group 2A, Vol. 17/Sup. 7, 1987). It is not listed under the Stockholm Convention on Persistent Organic Pollutants — whose Annexes A–C cover a specific, much smaller set of chlorinated pesticides, industrial chemicals and unintentional byproducts, none of them nitrosamines — and it is unrelated to the Minamata Convention, which is scoped specifically to mercury and mercury compounds. Regulatory — IARC · IARC Monograph Volume 17 (
CertificationsCertiPUR-US: does not name nitrosamines anywhere in its GHS-hazard-class prohibited substances, prohibited blowing agents, prohibited flame retardants, or VOC emissions-testing target list (confirmed directly against the 2025 Slabstock Technical Guidelines). The program's stated scope is flexible polyurethane foam; it does not cover latex foam — the material where nitrosamine risk actually concentrates, via rubber-vulcanization accelerators. OEKO-TEX Standard 100: restricted — Appendices 4/5 name N-Nitrosodimethylamine specifically (CAS 62-75-9, listed under the acronym "NDMA" among 15 individually-named N-nitrosamines), each capped at 0.5 mg/kg, with a 5 mg/kg cap on total N-nitrosatable substances, applied identically across all four OEKO-TEX product classes (Baby / direct skin contact / no skin contact / decoration material). GREENGUARD/GREENGUARD Gold: a low-VOC chamber-emissions certification that does not name nitrosamines among its approximately 35 individually-limited target VOCs, though its broader TVOC/GC-MS scan could in principle flag a volatile compound like this if present in the tested emissions. Industry — CertiPUR-US
The 72-hour test windowVolatile, not a hidden SVOC: NDMA has a boiling point of approximately 152–154°C (152°C per the peer-reviewed CRC Handbook of Chemistry and Physics; ~154°C per Weast 1983 as cited by ATSDR) and a comparatively high vapor pressure (2.7 mmHg at 20°C per ATSDR) — several orders of magnitude above the ~0.0001 mmHg (10⁻⁴ mm Hg) threshold ATSDR cites for a compound to exist almost entirely in the vapor phase. EPA and ATSDR both describe it as a volatile nitrosamine. A short chamber test is well-suited to detect it if present or actively off-gassing, though continuous low-level formation from residual nitrosatable amine precursors in rubber/latex components — rather than a one-time release — could still be missed by a single short snapshot test. Inferred — from the compound's volatility/emission profile versus the VOC focus of short chamber tests

What it is

NDMA is the simplest of the dialkylnitrosamines: two methyl groups on a nitrogen, joined to a nitroso (–N=O) group. It is a yellow liquid, semi-volatile, and soluble in both water and fat. Its notoriety is out of proportion to its size. NDMA is a genotoxic alkylating agent — it methylates DNA, producing mutations — and it is one of the most potent chemical carcinogens measured in animal studies, causing liver and other tumours at very low doses. Regulatory — IARC, Group 2A The U.S. National Toxicology Program lists it as reasonably anticipated to be a human carcinogen, and EPA's IRIS assessment assigns it one of the steepest cancer slope factors of any regulated chemical. Regulatory

Most people first heard of NDMA in 2018–2020, when trace amounts found in the heartburn drug ranitidine (Zantac) and in several valsartan-family blood-pressure medications led to global recalls. That episode is a useful mental model: NDMA is dangerous at vanishingly small quantities, and it tends to form as an unintended byproduct of other chemistry rather than being deliberately manufactured into products.

The formation recipe is simple and common: a secondary amine (dimethylamine is the classic precursor) plus a nitrosating agent (nitrite, or the chloramine and hypochlorite used as disinfectants). Both halves of that recipe are present in ordinary indoor environments — amines from skin, food, and many consumer products; nitrosating agents from chlorine-based cleaners and from combustion.

How it gets to the bedroom

From cleaning chemistry

This is the less obvious pathway and the more interesting one. When a nitrosating agent meets a secondary amine, NDMA can form. Disinfection-chemistry research established the mechanism quantitatively: in a controlled study of chloramination, hypochlorite (the active ingredient in chlorine bleach) formed roughly an order of magnitude more NDMA than monochloramine from the same dimethylamine precursor. Peer-reviewed — Schreiber & Mitch 2005, PMID 15952390 That study was conducted in water treatment, not on a bedroom surface — but the chemistry is the same chemistry, and amine residues are abundant on the surfaces around a bed. How much NDMA this produces in real indoor air has not been quantified. Inferred — the formation chemistry is established; the in-home air concentration is not measured

From thirdhand tobacco smoke

NDMA is one of the volatile nitrosamines present in tobacco smoke, and nitrosamine residues are a documented component of thirdhand smoke — the chemical film that settles into dust, bedding, and soft surfaces and re-emits for months after smoking stops. In a bedroom with a current or former smoking history, this is the most likely ongoing NDMA source, alongside the tobacco-specific nitrosamines NNK and NNN. Regulatory — tobacco smoke is a listed NDMA source

From rubber, food, and other sources

NDMA also occurs as a trace contaminant of some rubber products (a byproduct of vulcanization chemistry), and dietary exposure comes from cured and nitrite-preserved meats, where nitrite reacts with naturally present amines. These are real exposure routes but are not specific to the sleep environment; they are context for why NDMA is a compound worth knowing rather than bedroom-specific pathways.

What the research says

Documented health effects

The carcinogenicity evidence is strong in animals and mechanistically clear: NDMA is metabolised to a reactive species that methylates DNA, and it produces tumours — particularly in the liver — across many animal species at low doses. Regulatory — IARC Group 2A Direct human epidemiology is limited, which is why the classification is 2A (probable) rather than 1, but the combination of potency, genotoxic mechanism, and consistency across species is why regulators treat NDMA so conservatively. Regulatory — NTP, EPA IRIS

Bedroom-specific evidence

This is where honesty matters: there is little. The formation chemistry (cleaning) and the residue chemistry (thirdhand smoke) are both well-documented, but we are not aware of studies that have measured NDMA concentrations in residential bedroom air and partitioned the sources. The reasonable position is that NDMA is plausibly present at low levels where chlorine cleaners and amine residues coincide, or where thirdhand smoke is present, and that the quantity is unknown. Speculation — in-bedroom concentration and dose are unquantified

What helps reduce exposure

Limit chlorine-bleach and chloramine cleaners on bedroom-area surfaces. The nitrosating agent is the controllable half of the formation recipe. Using non-chlorine cleaning approaches near the bed, and ventilating after any chlorine cleaning, reduces the opportunity for NDMA to form.

Address thirdhand smoke. If the bedroom has a smoking history, the nitrosamine reservoir is in soft furnishings, dust, and surfaces. Replacing or deep-cleaning textiles, washing bedding, and sealing or repainting where feasible reduces the residue that re-emits.

Ventilate. As with other semi-volatile indoor pollutants, fresh-air exchange lowers accumulated concentrations.

Use activated-carbon filtration with adequate carbon mass. Carbon adsorbs NDMA moderately; capacity is limited, so sizing matters and the carbon needs periodic replacement.

What does NOT help

  • HEPA-only air purifiers. NDMA is a gas-phase / semi-volatile compound; particle filtration does not remove it.
  • "Antibacterial" chlorine cleaning as a catch-all. For NDMA specifically, more chlorine chemistry near amine residues is the wrong direction — it supplies the nitrosating agent.
  • Masking odour. NDMA is not the smell; air fresheners add VOCs without removing it.

Open research questions

  • The actual concentration of NDMA in residential bedroom air where chlorine cleaners and amine residues coincide. Speculation
  • The contribution of thirdhand-smoke nitrosamine reservoirs to airborne NDMA in the sleep environment. Speculation
  • Activated-carbon capture performance for NDMA at the very low concentrations relevant to indoor air. Speculation

The Embr Exposure Ledger: N-Nitrosodimethylamine

One chemical, several public questions, answered from independent datasets and joined here — the environment it shows up in, the body burden it carries, how it is regulated, and what actually reduces it.

This compound appears in 5 of the Embr Exposure Ledger’s 10 exposure datasets.
Is it around me?
Detected in 27.05% of 1,198 U.S. public water systems monitored in 2008-2010.Source: EPA UCMR 2 — Unregulated Contaminant Monitoring Rule, 2nd cycle
Is it in the air?
In U.S. outdoor air: about 0.0012 in a million added lifetime cancer risk.Source: EPA AirToxScreen (2020) — modeled ambient air-toxics concentrations and risk
At what level would it matter?
Published benchmarks exist: an inhalation reference concentration of 4e-05 mg/m³ (PPRTV appendix) and a residential indoor-air screening level of 7.2e-05 µg/m³, set on a cancer endpoint (1-in-a-million excess lifetime risk). A screening level is the concentration at which EPA would look further, not a boundary between safe and harmful. The ledger holds no measured sleeping-environment concentration for this compound, so there is nothing here to compare the benchmark against — it tells you what would matter, not what is in any room.Source: US EPA, Regional Screening Levels (RSL) Summary Table — consolidated toxicity values from IRIS, PPRTV, ATSDR, Cal EPA and OPP
Does the law flag it?
Listed under California Proposition 65 for cancer since 1987. Carries an EU-wide binding classification as carcinogenic (category 1B). That classifies the substance itself; it does not restrict any product.Source: California OEHHA Proposition 65 List (Safe Drinking Water and Toxic Enforcement Act of 1986)Source: EU CLP Annex VI
Has a regulator acted?
Regulators have acted on products over this compound: 19 EU safety alerts. These are actions against specific products, not a measure of the substance in general — and counts follow enforcement attention as much as they follow prevalence.Source: EU Safety Gate (RAPEX), European Commission rapid alert system for dangerous non-food products

Detection and body-burden figures are occurrence data, not a personal measurement or a health diagnosis. Part of the Embr Exposure Ledger — an open, cross-dataset chemical join (download the data), reusable with attribution.

Citations

  1. IARC. N-Nitrosodimethylamine — Group 2A (probably carcinogenic to humans). Regulatory
  2. NTP. 15th Report on Carcinogens — N-Nitrosodimethylamine (reasonably anticipated to be a human carcinogen). Regulatory
  3. EPA. Integrated Risk Information System (IRIS) — N-Nitrosodimethylamine. Regulatory
  4. ATSDR. Toxicological Profile for N-Nitrosodimethylamine. Regulatory
  5. Schreiber IM, Mitch WA (2005). Influence of the order of reagent addition on NDMA formation during chloramination. Environmental Science & Technology. PMID 15952390 Peer-reviewed

Frequently asked questions

  • What is NDMA and why is it considered so dangerous?

    NDMA (N-nitrosodimethylamine) is a small nitrosamine that is one of the most potent carcinogens known by mass — a genotoxic agent that damages DNA, carcinogenic in animals at very low doses. IARC classifies it as Group 2A and the U.S. National Toxicology Program lists it as reasonably anticipated to be a human carcinogen. It became widely known when trace NDMA contamination triggered global recalls of the heartburn drug ranitidine and several blood-pressure medications. Regulatory

  • Can cleaning products create NDMA in my home?

    NDMA forms when a nitrosating agent — such as the hypochlorite in chlorine bleach or chloramine — reacts with a secondary amine like dimethylamine. Amines are common residues from skin, foods, and many consumer products. Disinfection-chemistry research has shown hypochlorite can form roughly an order of magnitude more NDMA than chloramine from dimethylamine. The same chemistry can occur on household surfaces, although NDMA concentrations in indoor air from cleaning have not been well quantified.

  • Is NDMA in tobacco smoke?

    Yes. NDMA is one of the volatile nitrosamines present in tobacco smoke, and nitrosamine residues persist on surfaces and in dust as part of thirdhand smoke. In a bedroom with a current or former smoking history, this is the most likely ongoing NDMA source.

  • Does activated carbon remove NDMA?

    Activated carbon adsorbs NDMA with moderate effectiveness. NDMA is small and water-soluble, so capacity is more limited than for larger, more lipophilic compounds, and early breakthrough at very low concentrations has been documented in water treatment. Adequately sized carbon media improves capture.

  • Should I worry about NDMA from my mattress?

    A mattress is not a primary NDMA source. The relevant bedroom pathways are cleaning chemistry (chlorine-based products reacting with amine residues) and thirdhand tobacco smoke. Rubber products can contain trace nitrosamines from vulcanization, but finished consumer mattresses are not a documented major source. Reducing chlorine-cleaner use on bedding-area surfaces and addressing thirdhand smoke are the meaningful steps.

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Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.

Last reviewed 2026-06-26. If you find a factual error, contact us.