(Also known as: formalin; methanal; methyl aldehyde; methylene oxide; paraformaldehyde)
SUMMARY
Formaldehyde tends to be used as a disinfectant for soil, equipment, yards etc. but also has some fungicidal activity. It is highly toxic and highly volatile. Risk of drift is a concern. It is not persistent in soil systems and the potential for leaching to groundwater is low. It is highly toxic to mammals, a recognised carcinogen and severe irritant. It may also cause genetic defects. It is moderately toxic to most biodiversity species.
Data alerts
The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.
Listed on USA Toxic Release Inventory; Registered as a UK Commodity Substance; Subject to the provisions of the UK Poisons Act 1972; Some applications may be approved under the GB Biocide Products Regulations
Relevant Environmental Water Quality Standards
UK Environment Agency non-statutory standard for the protection of aquatic life in fresh surface water: 5 µg l⁻¹ as annual average, 50 µg l⁻¹ as max acceptable conc.
Example manufacturers & suppliers of products using this active now or historically
-
Example products using this active
Formalin Fungicide
Formulation and application details
Often used as a dip, drench or spray treatment. May also be used as a fumigant to sterilise animal houses.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
550000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
High
Solubility - In organic solvents at 20 °C (mg l⁻¹)
Miscible
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Acetone
-
Melting point (°C)
-92
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
-
Boiling point (°C)
-19.2
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
-
Degradation point (°C)
-
-
-
Flashpoint (°C)
50
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
-
Octanol-water partition coefficient at pH 7, 20 °C
P
2.24 X 1000
Calculated
-
Log P
0.35
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Low
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
0.82
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
13.27
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
-
Strong base
Vapour pressure at 20 °C (mPa)
53300000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Highly volatile. If applied directly to plants or soil, drift is a concern & mitigation is advisable
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
3.41 X 10-02
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Non-volatile
Volatilisation as max % of applied dose lost
From plant surface
-
-
-
From soil surface
-
-
-
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)
6
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
Non-persistent
DT₅₀ (lab at 20 °C)
1.9
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
Non-persistent
DT₅₀ (field)
-
-
-
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Other sources: DT₅₀ 2-20 days
Dissipation rate RL₅₀ (days) on plant matrix
Value
-
-
-
Note
-
Dissipation rate RL₅₀ (days) 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
Stable
P2 P = Other non-EU, UK or US Governments and Regulators 2 = Unverified data of unknown source
Stable
Note
-
Water-sediment DT₅₀ (days)
-
-
-
Water phase only DT₅₀ (days)
-
-
-
Sediment phase only DT₅₀ (days)
-
-
-
Air degradation
As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.
Decay in stored produce DT₅₀
-
Soil adsorption and mobility
Property
Value
Source; quality score; and other information
Interpretation
Linear
Kd (mL g⁻¹)
-
A3 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 ) 3 = Unverified data of known source
Mobile
Koc (mL g⁻¹)
37
Notes and range
Other sources: DT₅₀ 2-20 days
Freundlich
Kf (mL g⁻¹)
-
-
-
Kfoc (mL g⁻¹)
-
1/n
-
Notes and range
-
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
0.68
Calculated
Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
1.64 X 10-03
Calculated
-
Note
-
Potential for particle bound transport index
Low
Calculated
-
Potential for loss via drain flow
Mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
0.2
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
Low potential
CT₅₀ (days)
Not available
-
Known metabolites
None
ECOTOXICOLOGY
Terrestrial ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)
> 550
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
Moderate
Mammals - Short term dietary NOEL
(mg kg⁻¹)
-
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
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)
-
-
-
Chronic
-
-
-
Notes
-
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 bee species (1)
Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)
-
-
-
Mode of exposure
-
Other bee species (2)
Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)
-
-
-
Mode of exposure
-
Beneficial insects (Ladybirds)
-
-
-
Beneficial insects (Lacewings)
-
-
-
Beneficial insects (Parasitic wasps)
-
-
-
Beneficial insects (Predatory mites)
-
-
-
Beneficial insects (Ground beetles)
-
-
-
Aquatic ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
> 1.84
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
Oncorhynchus mykiss
Moderate
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)
-
-
-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
41.0
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
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
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Phyllospora comosa
Moderate
Mesocosm study data
NOEAEC mg l⁻¹
-
-
-
NOEAEC mg l⁻¹
-
-
-
Marine bivalves
-
-
-
HUMAN HEALTH AND PROTECTION
General
Property
Value
Source; quality score; and other information
Interpretation
Threshold of Toxicological Concern (Cramer Class)
Low (class I)
-
-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)
> 550
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
Moderate
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)
270
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Rabbit
-
Mammals - Inhalation LC₅₀ (mg l⁻¹)
> 0.6
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Most probable exposure route is via inhalation - PPE/PPC essential
MRLs
European
EU MRL pesticide database
Great Britain
GB MRL Register
Notes
-
Drinking Water Standards
-
-
-
Drinking Water MAC (μg l⁻¹)
-
-
-
Mammalian dose elimination route and rate
-
-
-
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
?Possibly, status not identified
XNo, known not to cause a problem
XNo, known not to cause a problem
Respiratory tract irritant
Skin irritant
Skin sensitiser
✓Yes, known to cause a problem
✓Yes, known to cause a problem
✓Yes, known to cause a problem
Eye irritant
Phototoxicant
✓Yes, known to cause a problem
No data found
General human health issues
IARC Group 1 carcinogen, UK HSE - carcinogen; CLP data - known human carcinogen; US NTP - known carcinogen; OSHA - known human carcinogen; US EPA - probable human carcinogen Severe obstructive tracheobronchitis may result from inhalation causing throat spasms and a build up of fluid in the lungs, leading to death Suspected of causing genetic defects May cause serious damage of the gastrointestinal tract
Handling issues
Property
Value and interpretation
General
Flammable gas Reacts explosively with peroxides and performic acid IMDG Tranport Class 3
CLP classification 2013
Health: H301, H311, H314, H317, H331, H341, H350
WHO Classification
Not classified: Fumigant (Not classified: Fumigant)
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
Environmental fate
Ecotoxicity
