endrin ** nendrin ** OMS 197 ** aldrin epoxide ** Experimental Insecticide 269 ** Translations

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SUMMARY

Endrin is an obsolete, multi-use organochlorine insecticide that is not approved for use in the EU. It has a low aqueous solubility and is non-volatile. Based on its chemical properties it is not expected to leach to groundwater. Endrin tends to be persistent in soil systems. It is highly toxic to mammals and is a neurotoxin. It is also highly toxic to birds, honeybees and most aquatic organisms but slightly less so to earthworms.

GENERAL INFORMATION
for endrin

Description: A multi-use but now obsolete pesticide used to control insects, rodents, and birds.

Example pests controlled: Aphids; Lygus bugs; Grasshoppers; Small mammals including mice, voles

Example applications: Field crops; Cotton; Grains; Rice; Sugarcane

Efficacy & activity: -

Availability status: Obsolete, Banned

Introduction & key dates: 1950s

EC Regulation 1107/2009 (repealing 91/414):

Status	Not approved
Dossier rapporteur/co-rapporteur	-
Date inclusion expires	Expired
EU Candidate for substitution (CfS)	-
Listed in EU database	Yes

Approved for use () or known to be used () in the following European countries:

AT

BE

BG

CY

CZ

DE

DK

EE

EL

ES

FI

FR

HR

HU

IE

IT

LT

LU

LV

MT

NL

PL

PT

RO

SE

SI

SK

UK

Chemical structure:

Isomerism	Isomeric
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-GKRDHZSOSA-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-/m0/s1
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams:

Common Name	Relationship	Link
Endrin	Unstated isomer

General status:

Pesticide type	Insecticide, Avicide, Rodenticide
Substance group	Organochlorine
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Broad-spectrum, with contact and stomach action. Is a chloride channel-blocking agent.
CAS RN	72-20-8
EC number	200-775-7
CIPAC number	28
US EPA chemical code	041601
PubChem CID	12358480
Molecular mass (g mol-1)	380.91
PIN (Preferred Identification Name)	(1aR,2R,2aR,3R,6S,6aS,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	1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-exo-1,4-exo-5,8-dimethanonaphthalene
CAS name	(1aR,2R,2aR,3R,6S,6aS,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 - regulated by Stockholm Convention; LRTAP Annex I; PAN Dirty Dozen; OSPAR soc; Severe Marine Pollutant
Relevant Environmental Water Quality Standards	EU Directive 2008/105/EC EQS for the sum of all cyclodiene pesticides in: inland surface waters: 0.01 ug/L; Other surface waters; 0.005 ug/L as annual average
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	Not known
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	Many recorded cases Aphis gossypii Culex pipiens pipiens Empoasca biguttula Leptocorisa oratorius Spodoptera littoralis many others
Physical state	White crystals
Related substances & organisms	-

Formulations:

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Shell Chemical Company Velsicol
Example products using this active	Endrex Mendrin Nendrin Hexadrin
UK LERAP status	No UK approval for use as a pesticide under EC Regulation 1107/2009
Formulation and application details	Available in a variety of formulations including wettable powders and emulsifiable concentrates.

ENVIRONMENTAL FATE
for endrin

Property		Value	Source/Quality Score/Other Information	Interpretation
Solubility - In water at 20oC (mg l-1)		0.24	H4	Low
Solubility - In organic solvents at 20oC (mg l-1)		-	-	-
Melting point (oC)		200	V3	-
Boiling point (oC)		-	-	-
Degradation point (oC)		-	-	-
Flashpoint (oC)		-	-	-
Octanol-water partition coefficient at pH 7, 20oC	P	1.58 X 1003	Calculated	-
	Log P	3.2	H4	High
Bulk density (g ml-1)/Specific gravity		1.84	Q2	-
Dissociation constant (pKa) at 25oC		-	-	-
		Note:
Vapour pressure at 20oC (mPa)		2.0 X 10-07	F4	Low volatility
Henry's law constant at 25oC (Pa m3 mol-1)		1.48 X 10-01	H4	Moderately volatile
GUS leaching potential index		0.00	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		-	Calculated	High
Maximum UV-vis absorption L mol-1 cm-1		-	-	-
Surface tension (mN m-1)		-	-	-

Degradation:

Property		Value	Source/Quality Score/Other Information	Interpretation
General biodegradability		-
Soil degradation (days) (aerobic)	DT50 (typical)	4300	M4	Very persistent
	DT50 (lab at 20oC)	-	-	-
	DT50 (field)	-	-	-
	DT90 (lab at 20oC)	-	-	-
	DT90 (field)	-	-	-
	DT50 modelling endpoint	-	-	-
	Note	Other sources: DT50 up to 12 years (R3); FAO state DT50 4-14 days
Dissipation rate RL50 on plant matrix	Value	3.3	R3	-
	Note	Birdsfoot trefoil leaves, n=1
Dissipation rate RL50 on and in plant matrix	Value	4.0	R4	-
	Note	Published literature RL50 range 1.0-7.0 days, 2 field crops, various matrices, n=2
Aqueous photolysis DT50 (days) at pH 7	Value	-	-	-
	Note	-
Aqueous hydrolysis DT50 (days) at 20oC and pH 7	Value	-	-	-
	Note	-
Water-sediment DT50 (days)		-	-	-
Water phase only DT50 (days)		-	-	-

Soil adsorption and mobility:

Property		Value	Source/Quality Score/Other Information	Interpretation
Linear	Kd	-	H3	Non-mobile
	Koc	10000
	Notes and range	Other sources: 31623 mL/g (R3)
Freundlich	Kf	-	-	-
	Kfoc	-
	1/n	-
	Notes and range	-
pH sensitivity		-

Other known metabolites:

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
endrin aldehyde Note: Persistent	-	Soil	-	-

ECOTOXICOLOGY
for endrin

Property		Value	Source/Quality Score/Other Information	Interpretation
Bio-concentration factor	BCF (l kg-1)	3970	R3 (whole body, Literature values log BCF range 2.2-3.4 (R3))	Threshold for concern
	CT50 (days)	Not available		-
Mammals - Acute oral LD50 (mg kg-1)		> 7.5	R3 Rat	High
Mammals - Short term dietary NOEL	(mg kg-1)	-	-	-
	(ppm diet)	-		-
Birds - Acute LD50 (mg kg-1)		5.6	R3 Anas platyrhynchos	High
Birds - Short term dietary (LC50/LD50)		-	-	-
Fish - Acute 96 hour LC50 (mg l-1)		0.00073	F4 Oncorhynchus mykiss	High
Fish - Chronic 21 day NOEC (mg l-1)		-	-	-
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1)		0.0042	F4 Daphnia magna	High
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	Contact acute 48 hour LD50 (μg bee-1)	> 0.46	F4	High
	Oral acute 48 hour LD50 (μg bee-1)	-	-	-
	Unknown mode acute 48 hour LD50 (μg bee-1)	-	-	-
Earthworms - Acute 14 day LC50 (mg kg-1)		> 66	F4 Lumbricus terrestris	Moderate
Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1)		-	-	-
Other soil macro-organisms - e.g. Collembola	LR50 / EC50 / NOEC / % Effect	-	-	-
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
for endrin

General:

Property		Value	Source/Quality Score/Other Information	Interpretation
Threshold of Toxicological Concern (Cramer Class)		High (class III)	-	-
Mammals - Acute oral LD50 (mg kg-1)		> 7.5	R3 Rat	High
Mammals - Dermal LD50 (mg kg-1 body weight)		5.0	R3 Rat	-
Mammals - Inhalation LC50 (mg l-1)		-	-	-
Other Mammal toxicity endpoints		-		-
ADI - Acceptable Daily Intake (mg kg-1bw day-1)		0.0002	A5	-
ARfD - Acute Reference Dose (mg kg-1bw day-1)		-	-	-
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1)		-	-	-
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1)		-	-	-
Dermal penetration studies (%)		-	-	-
Dangerous Substances Directive 76/464		List I; List II	-	-
Exposure Limits		[UK LT TWA 8 hr: 380 mg/m3]	Occupation Exposure	-
Exposure Routes	Public	-
	Occupational	-
European MRLs		Click here for the EU MRL pesticide database
Drinking Water Standards		Non-statutory WHO drinking water guideline 0.0006 mg/L	UK EA QS database, 2018	-
Drinking Water MAC (μg l-1)		-	-	-

Health issues:

Carcinogen	Mutagen	Endocrine disrupter	Reproduction / development effects	Cholinesterase inhibitor	Neurotoxicant
	-
Respiratory tract irritant	Skin irritant	Skin sensitiser	Eye irritant	Phototoxicant
		-		-
General human health issues		Highly toxic Endocrine issues - Competitive binding to androgen receptors

: Yes, known to cause a problem
: No, known not to cause a problem
: Possibly, status not identified
- : No data found

Handling issues:

Property		Value	Source/Quality Score/Other Information	Interpretation
General		No information available
CLP classification 2013		Health: H300, H311 Environment: H400, H410
EC Risk Classification		T+ - Very toxic: R28 T - Toxic: R24 N - Dangerous for the environment: R50, R53
EC Safety Classification		S1/2, S22, S36/37, S45, S60, S61
WHO Classification		O	-	Obsolete substance
US EPA Classification (formulation)		I	-	Danger - Highly toxic
UN Number		2761
Waste disposal & packaging		-

TRANSLATIONS
for endrin

Language	Name
English	endrin
French	endrine
German	Endrin
Danish	endrin
Italian	endrin
Spanish	endrin
Greek	endrin
Slovenian	endrin
Polish	endryna
Swedish	-
Hungarian	-
Dutch	endrine

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Record last updated: Wednesday 31 October 2018
Contact: aeru@herts.ac.uk