Dieldrin (Ref: ENT 16225 )	Last updated: 24/08/2024
(Also known as: dieldrex; dieldrite; SD 3417; dieldrine)

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SUMMARY

Dieldrin is an obsolete insecticide. It has a low aqueous solubility and is volatile. Based on its chemical properties, it is not expected to leach to groundwater. Its data suggests it is very persistent in soils and is non-mobile. It is highly toxic to mammals with a high potential for bioaccumulation. It is a neurotoxin and probably a mutagen. Dieldrin has a moderate toxicity to birds, aquatic invertebrates and algae but considered to be more toxic to fish and honeybees.

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.

Environmental fate	Ecotoxicity	Human health
Environmental fate High alert: Very persistent; Potential for particle bound transport: High	Ecotoxicity High alert: Fish acute ecotoxicity: High; Bees acute unknown ecotoxicity: High	Human health High alert: Mammals acute toxicity: High; Genotoxic; Endocrine disrupter; Reproduction/development effects; Neurotoxicant

GENERAL INFORMATION

Description	An obsolete cyclodiene insecticide. Can also be a pesticide transformation product
Example pests controlled	Termites; Locusts; Wood eating insects; Fabric eating insects
Example applications	Wood; Fabrics; Public health situations
Efficacy & activity	-
Availability status	Considered obsolete but may be available in some countries; Banned in many countries
Introduction & key dates	1949, first reported

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
Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries	ISIceland NONorway

Additional information

Also used in	-

Chemical structure

Isomerism	Dieldrin is a stereoisomer of endrin
Chemical formula	C₁₂H₈Cl₆O
Canonical SMILES	C1C2C3C(C1C4C2O4)C5(C(=C(C3(C5(Cl)Cl)Cl)Cl)Cl)Cl
Isomeric SMILES	C1[C@@H]2[C@H]3[C@@H]([C@H]1[C@H]4[C@@H]2O4)[C@]5(C(=C([C@@]3(C5(Cl)Cl)Cl)Cl)Cl)Cl
International Chemical Identifier key (InChIKey)	DFBKLUNHFCTMDC-PICURKEMSA-N
International Chemical Identifier (InChI)	InChI=1S/C12H8Cl6O/c13-8-9(14)11(16)5-3-1-2(6-7(3)19-6)4(5)10(8,15)12(11,17)18/h2-7H,1H2/t2-,3+,4+,5-,6-,7+,10+,11-
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
dieldrin	Unstated isomer

General status

Pesticide type	Insecticide, Metabolite
Metabolite Type	Soil
Substance groups	Cyclodiene insecticide
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Central nervous system stimulant. GABA-gated chloride channel antagonist. Contact and stomach action
CAS RN	60-57-1
EC number	200-484-5
CIPAC number	16
US EPA chemical code	045001
PubChem CID	969491
CLP index number	602-049-00-9
Molecular mass	380.91
PIN (Preferred Identification Name)	(1aR,2R,2aS,3S,6R,6aR,7S,7aS)-3,4,5,6,9,9-hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-dimethanonaphth[2,3-b]oxirene
IUPAC name	(1R,4S,4aS,5R,6R,7S,8S,8aR)-1,2,3,4,10,10-hexachloro-1,4,4a,5,6,7,8,8a-octahydro-6,7-epoxy-1,4:5,8-dimethanonaphthalene
CAS name	(1aR,2R,2aS,3S,6R,6aR,7S,7aS)-rel-3,4,5,6,9,9-hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-dimethanonaphth(2,3-b)oxirene
Other status information	WFD priority substance; POP; LRTAP Annex I; PAN Dirty Dozen; OSPAR soc; Marine Pollutant; Rotterdam Convention (Class O) - subject to PIC regulations
Relevant Environmental Water Quality Standards	EU Directive 2008/105/EC EQS sum of all cyclodiene pesticides in: Inland surface waters as annual average: 0.01 µg l⁻¹; Other surface waters; 0.005 µg l⁻¹
Herbicide Resistance Class (HRAC MoA class)	Not applicable
Herbicide Resistance Class (WSSA MoA class)	Not applicable
Insecticide Resistance Class (IRAC MoA class)	2A
Fungicide Resistance Class (FRAC MOA class)	Not applicable
Examples of recorded resistance	Many recorded cases, Agriotes lineatus, Agriotes obscurus, Anopheles sacharovi, Blattella germanica, Chironomus zealandicus, Epitrix cucumeris, Plusia gamma
Physical state	White to light brown crystals
Related substances & organisms	endrin

Can be a metabolite of:

Parent	Formation medium	Estimated maximum occurrence fraction	1107/2009 relevancy
aldrin	Soil	-	-

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Shell Chemical Co. Hyman
Example products using this active	Octalox Panoram D-31 Alvit Dieldrex
Formulation and application details	Usually supplied in a variety of formulations including wettable powders, granules and emulsifiable concentrates

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		0.14	H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		-	-	-
Melting point (°C)		177	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Boiling point (°C)		385	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	5.01 X 1003	Calculated	-
	Log P	3.7	H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data	High
Fat solubility of residues	Solubility	Soluble	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	-
	Data type	Regulatory data - observed in metabolism and farm animal feeding studies	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	-
Density (g ml⁻¹)		1.75	F4 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 ) 4 = Verified data	-
Dissociation constant pKa) at 25 °C		Not applicable	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
		No dissociation
Vapour pressure at 20 °C (mPa)		0.024	H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		6.50 X 10-02	H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data	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)	1400	M4 M = GLEAMS Model database (Groundwater Loading Effects of Agricultural Management Systems). Dataset no longer available. 4 = Verified data	Very persistent
	DT₅₀ (lab at 20 °C)	2000	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	Very persistent
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Best available data, PIC DGD DT₅₀ 5 years; Other sources: DT₅₀ 800-900 days (R3)
Dissipation rate RL₅₀ (days) on plant matrix	Value	6.8	R4 R = Peer reviewed scientific publications 4 = Verified data	-
	Note	Published literature RL₅₀ range 6.5-7.0 days, 2 field crops, various matrices, n=2
Dissipation rate RL₅₀ (days) on and in plant matrix	Value	6.0	R4 R = Peer reviewed scientific publications 4 = Verified data	-
	Note	Published literature RL₅₀ range 2.0-10.0 days, 6 field crops, various matrices, n=8
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)		-	-	-
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)	-	H3 H = The US ARS pesticide properties database. Dataset is no longer available. 3 = Unverified data of known source	Non-mobile
	Koc (mL g⁻¹)	12000
	Notes and range	-
Freundlich	Kf (mL g⁻¹)	1563	Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source	-
	Kfoc (mL g⁻¹)	-
	1/n	0.95
	Notes and range	Mean of 3 soils. Organic Kf=4246; Sandy loam Kf=338; Sand Kf=106
pH sensitivity		-

Fate indices

Property		Value	Source; quality score; and other information	Interpretation
GUS leaching potential index		-0.26	Calculated	Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	5.35 X 10-03	Calculated	-
	Note	Estimated concentrations of chemicals with Koc values greater than 9995 ml g⁻¹ are beyond the scope of the regression data used in SCI-GROW development. If there are concerns for such chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the concentration returned by SCI-GROW
Potential for particle bound transport index		High	Calculated	-
Potential for loss via drain flow		Non-mobile	Calculated	-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk		-	-	-
Bio-concentration factor	BCF (l kg⁻¹)	35000	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Whole body (Literature values Log BCF range 1.4-4.1 ( R3 R = Peer reviewed scientific publications 3 = Unverified data of known source ))	High potential
	CT₅₀ (days)	1		-

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		46	F4 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 ) 4 = Verified data Rat	High
Mammals - Short term dietary NOEL	(mg kg⁻¹)	-	Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source Rat	-
	(ppm diet)	0.5		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		153	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 Anas platyrhynchos	Moderate
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		100	R4 R = Peer reviewed scientific publications 4 = Verified data Eisenia foetida	Moderate
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)		-	-	-
Soil micro-organisms		-	-	-
Collembola	Acute LC₅₀ (mg kg⁻¹)	-	-	-
	Chronic NOEC (mg kg⁻¹)	-	-	-
Non-target plants		-	-	-
		-	-	-
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)	0.32	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	High
	Chronic	-	-	-
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)	0.029	R4 R = Peer reviewed scientific publications 4 = Verified data Trigona spinipes	High
	Mode of exposure	Contact
Other bee species (2)	Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)	0.0036	R4 R = Peer reviewed scientific publications 4 = Verified data Megachile rotundata	High
	Mode of exposure	Contact
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)		0.0012	F4 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 ) 4 = Verified data Oncorhynchus mykiss	High
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		0.00225	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 Danio rerio Embryo	High
Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		0.25	F4 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 ) 4 = Verified data Daphnia magna	Moderate
Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (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)		57	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Chironomus dilutus 10 day LC₅₀	Moderate
Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)		-	-	-
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		0.1	F4 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 ) 4 = Verified data Chlorella pyrenoidosa	Moderate
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		-	-	-
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)		46	F4 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 ) 4 = Verified data Rat	High
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		60	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		-	-	-
Other Mammal toxicity endpoints		-	-	-
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		List II	-	-
Exposure Routes	Public	-
	Occupational	Can be absorbed into the body via dermal and inhalation routes
MRLs	European	EU MRL pesticide database
	Great Britain	GB MRL Register
	Notes	-
Drinking Water Standards		-	-	-
Drinking Water MAC (μg l⁻¹)		0.03	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 PIC DGD - WHO recommendation max limit 0.03 µg l⁻¹	-
Mammalian dose elimination route and rate		-	-	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor ?Possibly, status not identified A3 A = Chromosome aberration (EFSA database) 3 = Negative ; 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 ✓Yes, known to cause a problem Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant ✓Yes, known to cause a problem XNo, known not to cause a problem ✓Yes, known to cause a problem Respiratory tract irritant Skin irritant Skin sensitiser No data found No data found No data found Eye irritant Phototoxicant   No data found No data found
General human health issues		Extremely hazardous Exposure can lead to convulsions IARC Group 3 carcinogen - not classifiable; CLP data - suspected carcinogen; US EPA - probable human carcinogen Endocrine issues - Competitive binding to androgen receptors, estrogenic effect

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	Health: H301, H310, H351, H372 Environment: H400, H410
WHO Classification	Ib (Highly hazardous)
UN Number	-
Waste disposal & packaging	-
Shelf-life, storage, stability and reactivity	-

TRANSLATIONS

Language	Name
English	dieldrin
French	dieldrine
German	Dieldrin
Danish	dieldrin
Italian	dieldrin
Spanish	dieldrin
Greek	dieldrin
Polish	dieldryna
Swedish	-
Hungarian	-
Dutch	dieldrine
Norwegian	-

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Record last updated:	24/08/2024
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