Dienochlor (Ref: SAN 804)	Last updated: 22/01/2023
(Also known as: decachlor; dienochlore; HRS 1654; HRS 16A)

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SUMMARY

Dienochlor is an obsolete organochlorine insecticide. It has a low aqueous solubility and is quite volatile. Its data suggests it is persistent in soils. It is not toxic to mammals but does high a potential for bioaccumulation. Dienochlor has a moderate toxicity to aquatic invertebrates but considered to be more toxic to fish. It is relatively non-toxic to birds

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: Potential for particle bound transport: High Warning: Significant data are missing	Ecotoxicity High alert: Fish acute ecotoxicity: High	Human health Low alert

GENERAL INFORMATION

Description	An obsolete insecticide once used to control of plant-damaging mites on ornamentals
Example pests controlled	Various mites including two-spotted spider, tumid spider, strawberry spider, spruce spider, citrus red, European red, carmine, clover, McDaniel mite and the privet mite
Example applications	Ornamental shrubs and trees outside and within greenhouses
Efficacy & activity	-
Availability status	Considered obsolete but may be available in some countries
Introduction & key dates	1964, first reported

UK regulatory status

UK COPR regulatory status	Not approved
Date COPR inclusion expires	Expired
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	-
Date EC 1107/2009 inclusion expires	Expired
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

Additional information

Also used in	-

Chemical structure

Isomerism	None
Chemical formula	C₁₀Cl₁₀
Canonical SMILES	C1(=C(C(C(=C1Cl)Cl)(C2(C(=C(C(=C2Cl)Cl)Cl)Cl)Cl)Cl)Cl)Cl
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	LWLJUMBEZJHXHV-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C10Cl10/c11-1-2(12)6(16)9(19,5(1)15)10(20)7(17)3(13)4(14)8(10)18
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
dienochlor	-

General status

Pesticide type	Acaricide, Insecticide, Ovicide
Substance groups	Organochloride insecticide; Organochloride acaricide
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Contact action, destabilises nerve cell membranes. GABA-gated chloride channel antagonist.
CAS RN	2227-17-0
EC number	218-763-5
CIPAC number	None allocated
US EPA chemical code	027501
PubChem CID	16686
CLP index number	No data found
Molecular mass	474.8
PIN (Preferred Identification Name)	1,1',2,2',3,3',4,4',5,5'-decachlorobi(cyclopenta-2,4-diene)
IUPAC name	perchloro-1,1'-bicyclopenta-2,4-diene
CAS name	1,1',2,2',3,3',4,4',5,5'-decachlorobi-2,4-cyclopentadien-1-yl
Other status information	-
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	2A
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	Tetranychus urticae
Physical state	Colourless to grey coloured crystalline solid

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Novartis Dow Hooker: Zoecon
Example products using this active	Pentac
Formulation and application details	Usually supplied as a wettable powder or as flowable concentrates

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		0.025	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		590000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Toluene	-
		47700	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source n-Octanol	-
Melting point (°C)		122	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Boiling point (°C)		-	-	-
Degradation point (°C)		250	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	6.92 X 1003	Calculated	-
	Log P	3.84	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	High
Fat solubility of residues	Solubility	Likely to be soluble	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
	Data type	Based on chemical group	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Density (g ml⁻¹)		1.94	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		1.3	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		69.3	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Moderately volatile
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)	300	DW4 DW = Don Wauchope personal database for Pka data: Wauchope, R. D. and Edwards, J. Dissociation constants for pesticide active ingredients: a database and comparison with predicted values. MS in preparation 4 = Verified data	Persistent
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Best available data
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	-	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Slightly mobile
	Koc	783
	Notes and range	Literature range 196-1000 mL g⁻¹
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		2.74	Calculated	Transition state
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	2.35 X 10-01	Calculated	-
	Note	-
Potential for particle bound transport index		High	Calculated	-
Potential for loss via drain flow		Slightly mobile	Calculated	-
Bio-concentration factor	BCF (l kg⁻¹)	2700000	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source Estimated	High 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)		> 3160	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source Rat	Low
Mammals - Short term dietary NOEL	(mg kg⁻¹)	6.3	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source Rat	High
	(ppm diet)	-		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		3966	F5 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 5 = Verified data used for regulatory purposes Anas platyrhynchos	Low
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		> 1000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Eisenia foetida	Low
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)	> 36.0	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Moderate
	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	-	-	-
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	-
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
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		0.05	F5 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 5 = Verified data used for regulatory purposes Oncorhynchus mykiss	High
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		1.2	F5 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 5 = Verified data used for regulatory purposes Daphnia magna	Moderate
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)		-	-	-
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		-	-	-
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)		> 3160	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source Rat	Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		2000	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 I; List II	-	-
Exposure Routes	Public	Low risk to Europeans as no longer approved for use
	Occupational	Low risk to Europeans as no longer approved for use
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 XNo, known not 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 ; E0 E = Unspecified genotoxicity type (miscellaneous data source) 0 = No data No data found Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant No data found XNo, known not to cause a problem XNo, known not to cause a problem Respiratory tract irritant Skin irritant Skin sensitiser No data found ✓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		No further information available

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	Health: H302, H319 Environment: H400
WHO Classification	III (Slightly hazardous)
UN Number	2995
Waste disposal & packaging	-

TRANSLATIONS

Language	Name
English	dienochlor
French	dienochlore
German	Dienochlor
Danish	dienochlor
Italian	dienoclor
Spanish	dienoclor
Greek	-
Polish	dienochlor
Swedish	-
Hungarian	-
Dutch	-

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Record last updated:	22/01/2023
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