Trioxymethylene	Last updated: 20/03/2021
(Also known as: 1,3,5-trioxane; S-trioxane; metaformaldehyde; trioxin; paraformaldehyde; aldeform; trioxymethylen)

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GENERAL INFORMATION

Description	An outdated fungicide that has previously been used as a public health substance with a range of uses such as disinfecting sickrooms and linens
Example pests controlled	Broad spectrum of fungal pathogens
Example applications	Non-agricultural and utility applications
Efficacy & activity	-
Availability status	Unknown
Introduction & key dates	-

UK regulatory status

UK COPR regulatory status	Not approved
Date COPR inclusion expires	Not applicable
UK LERAP status	No UK approval for use

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status	Not approved
Dossier rapporteur/co-rapporteur	Not applicable
Date EC 1107/2009 inclusion expires	Not applicable
EU Candidate for substitution (CfS)	Not applicable
Listed in EU database	Yes
Approved for use (✓) under EC 1107/2009 in the following EU Member States	ATAustria BEBelgium BGBulgaria CYCyprus CZCzech Republic DEGermany DKDenmark EEEstonia ELGreece                   ESSpain FIFinland FRFrance HRCroatia HUHungary IEIreland ITItaly LTLithuania LULuxembourg                   LVLatvia MTMalta NLNetherlands PLPoland PTPortugal RORomania SESweden SISlovenia SKSlovakia

Also used in

Also used in	-

Chemical structure

Isomerism	-
Chemical formula	C₃H₆O₃
Canonical SMILES	C1OCOCO1
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	BGJSXRVXTHVRSN-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C3H6O3/c1-4-2-6-3-5-1/h1-3H2
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
trioxymethylene	-

General status

Pesticide type	Fungicide, Fumigant, Antibacterial
Substance group	Cyclic trimer of formaldehyde
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	-
CAS RN	110-88-3
EC number	203-812-5
CIPAC number	-
US EPA chemical code	-
PubChem CID	8081
Molecular mass	90.08
PIN (Preferred Identification Name)	1,3,5-trioxane
IUPAC name	1,3,5-trioxane
CAS name	1,3,5-trioxacyclohexane
Other status information	Potenial groundwater pollutant
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	Not applicable
Fungicide Resistance Classification (FRAC)	Not known
Examples of recorded resistance	-
Physical state	White crystalline solid

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	-
Example products using this active	-
Formulation and application details	-

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		221000	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	High
Solubility - In organic solvents at 20 °C (mg l⁻¹)		Insoluble	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Ethanol	-
		Insoluble	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Ether	-
Melting point (°C)		62	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Boiling point (°C)		115	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Sublimes	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		45	E4 E = Manufacturers safety data sheets 4 = Verified data (closed cup)	-
Octanol-water partition coefficient at pH 7, 20 °C	P	3.72 X 10-01	Calculated	-
	Log P	-0.43	V3 V = ChemID online databases / IPCS INCHEM (ChemID; IPCS INCHEM ) 3 = Unverified data of known source	Low
Bulk density (g ml⁻¹)		1.17	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		-	-	-
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		-	-	-
Maximum UV-vis absorption L mol⁻¹ cm⁻¹		-	-	-
Surface tension (mN m⁻¹)		-	-	-

Degradation

Property		Value	Source; quality score; and other information	Interpretation
General biodegradability		-
Soil degradation (days) (aerobic)	DT₅₀ (typical)	-	-	-
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	-
Dissipation rate RL₅₀ on plant matrix	Value	-	-	-
	Note	-
Dissipation rate RL₅₀ on and in plant matrix	Value	-	-	-
	Note	-
Aqueous photolysis DT₅₀ (days) at pH 7	Value	-	-	-
	Note	-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	-	-	-
	Note	-
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	-	-
	Koc	-
	Notes and range	-
Freundlich	Kf	-	-	-
	Kfoc	-
	1/n	-
	Notes and range	-
pH sensitivity		-

Fate indices

Property		Value	Source; quality score; and other information	Interpretation
GUS leaching potential index		-	-	-
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	Cannot be calculated	-	-
	Note	-
Potential for particle bound transport index		-	-	-
Potential for loss via drain flow		-	-	-

Key metabolites

Metabolite	Formation medium	Estimated maximum occurrence fraction	1107/2009 relevancy
formaldehyde	Acid media	-	Major fraction; Relevant

Other known metabolites

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
Formic acid	-	Air (oxidation)	-	Q3

ECOTOXICOLOGY

Property		Value	Source; quality score; and other information	Interpretation
Bio-concentration factor	BCF (l kg⁻¹)	-	-	-
	CT₅₀ (days)	-		-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 550	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Rat	Moderate
Mammals - Short term dietary NOEL	(mg kg⁻¹)	-	-	-
	(ppm diet)	-		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		-	-	-
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 14236	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Cyprinodon variegatus	Low
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		> 13219	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Daphnia magna	Low
Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)		-	-	-
Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)		-	-	-
Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)		-	-	-
Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)		-	-	-
Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)		-	-	-
Non-target plants		-	-	-
		-	-	-
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		-	-	-
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		-	-	-
Honeybees (Apis spp.)	Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
	Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
	Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
Bumblebees (Bombus spp.)	Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
		-
	Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
		-
Mason bees (Osmia spp.)	Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
	Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
Other pollinators (1)	Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)	-	-	-
	Mode of exposure	-
Other pollinators (2)	Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)	-	-	-
	Mode of exposure	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		-	-	-
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)		-	-	-
Other soil macro-organisms	Acute LC₅₀ (mg kg⁻¹)	-	-	-
	Chronic NOEC (mg kg⁻¹)	-	-	-
Other arthropod (1)	LR₅₀ g ha⁻¹	-	-	-
	% Effect	-	-	-
Other arthropod (2)	LR₅₀ g ha⁻¹	-	-	-
	% Effect	-	-	-
Soil micro-organisms		-	-	-
Mesocosm study data	NOEAEC mg l⁻¹	-	-	-
	NOEAEC mg l⁻¹	-	-	-

HUMAN HEALTH AND PROTECTION

General

Property		Value	Source; quality score; and other information	Interpretation
Threshold of Toxicological Concern (Cramer Class)		High (class III)	-	-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 550	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Rat	Moderate
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		-	-	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		0.203	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rat	-
Other Mammal toxicity endpoints		Intraperitoneal LD₅₀ = 425 mg kg⁻¹	A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes Rat	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		-	-	-
ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)		-	-	-
AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)		-	-	-
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)		-	-	-
Dermal penetration studies (%)		-	-	-
Dangerous Substances Directive 76/464		-	-	-
Exposure Routes	Public	-
	Occupational	-
MRLs	European	EU MRL pesticide database
	Notes	-
Drinking Water Standards		-	-	-
Drinking Water MAC (μg l⁻¹)		-	-	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor ✓Yes, known to cause a problem A0 A = Chromosome aberration (EFSA database) 0 = No data ; B0 B = DNA damage/repair (EFSA database) 0 = No data ; C0 C = Gene mutation (EFSA database) 0 = No data ; D0 D = Genome mutation (EFSA database) 0 = No data ; E1 E = Unspecified genotoxicity type (miscellaneous data source) 1 = Positive No data found Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant ✓Yes, known to cause a problem No data found No data found Respiratory tract irritant Skin irritant Skin sensitiser ✓Yes, known to cause a problem ✓Yes, known to cause a problem No data found Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		May cause pulmonary irritation, dermatitis, nausa, vomiting and loss of consciouness Harmful is swallowed or inhaled

Handling issues

Property	Value and interpretation
General	IMDG Transport Code is usually 4.1 Flammable May decompose to form flammable and/or explosive mixtures in air
CLP classification 2013	None allocated at this time
EC Risk Classification	Xn - Harmful: 22/36/37/38/40
EC Safety Classification	S26/28
WHO Classification	-
UN Number	2213
Waste disposal & packaging	Packaging Group III (minor danger)

TRANSLATIONS

Language	Name
English	trioxymethylene
French	-
German	Trioxymethylen
Danish	-
Italian	triossimetilene
Spanish	-
Greek	-
Polish	-
Swedish	-
Hungarian	-
Dutch	trioxymethyleen

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Record last updated:	20/03/2021
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242