DDT (Ref: OMS 16)

DDT (Ref: OMS 16)	Last updated: 05/01/2021
(Also known as: clofenotane; dichlorodiphenyltrichloroethane; dicofane; chlorophenothane; NCI C00464)

SUMMARY

DDT is a banned organochlorine insecticide. It has a low aqueous solubility, is relatively volatile and has a low potential to leach to groundwater. It is highly persistent in soil and non-mobile. It is moderately toxic by the oral route in humans and other mammals but is a carcinogen and endocrine disrupter. It shows a high to moderate level of toxicity to most animals and insects although it is relatively non-toxic to birds

GENERAL INFORMATION

Description

An obsolete and banned insecticide that was used to control insect vectors of disease, especially malaria

Example pests controlled

Mosquitoes; Houseflies; Body lice; Colarado beetles; Gypsy moths

Example applications

Agricultural crops; Domestic houses; Offices, commercial and industrial situations; Non-cropped sites including roads, rights-of-way; parkland

Efficacy & activity

Not applicable

Availability status

Obsolete, Banned since 1972

Introduction & key dates

1944

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

Not applicable

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

Also used in

Chemical structure

Isomerism

Isomer mix containing roughly 75-85% p,p'-DDT, 10-15% o,p'-DDT and a small amount of o,o'-DDT. Any balance is comprised of transformation products dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD).

Chemical formula

C₁₄H₉Cl₅

Canonical SMILES

C1=CC(=CC=C1C(C2=CC=C(C=C2)Cl)C(Cl)(Cl)Cl)Cl (for p,p'-DDT)

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

YVGGHNCTFXOJCH-UHFFFAOYSA-N (for p,p'-DDT)

International Chemical Identifier (InChI)

InChI=1S/C14H9Cl5/c15-11-5-1-9(2-6-11)13(14(17,18)19)10-3-7-12(16)8-4-10/h1-8,13H (for p,p'-DDT)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
o,p'-DDT	Isomer
DDT	Unstated isomer

General status

Pesticide type

Insecticide

Substance group

Organochlorine

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Non-systemic stomach and contact action. Sodium channel modulator.

CAS RN

50-29-3

EC number

200-024-3

CIPAC number

US EPA chemical code

029201

PubChem CID

3036

Molecular mass

354.49

PIN (Preferred Identification Name)

1,1'-(2,2,2-trichloroethane-1,1-diyl)bis(4-chlorobenzene)

IUPAC name

1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane

CAS name

1,1'-(2,2,2-trichloroethylidene)bis(4-chlorobenzene)

Other status information

WFD priority substance; Subject to PIC regulations; POP - regulated by Stockholm Convention; LRTAP Annex I; PAN Dirty Dozen; OSPAR soc; Marine Pollutant; Rotterdam Convention (Class II)

Relevant Environmental Water Quality Standards

EU Directive 2008/105/EC EQS for total DDT surface waters: annual average 0.025 µg l⁻¹
UK statutory standard for protection of aquatic life for inland, coastal & territorial surface waters: 0.025 µg l⁻¹ as annual mean conc

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Wide variety of insects are resistant, Aedes aegypti, Aedes vittatus, Amblyseius fallacis, Apis mellifera, many varieties of mosquito

Physical state

White crystalline powder

Related substances & organisms

p,p'-DDT

o,p'-DDT

o,o'-DDT

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Hildit
Heliotox
Didigam
Dinocide
Digmar
Genitox
Pentachlorin
Rukseam

Example products using this active

King Tech
Hindustan Insecticides Ltd.

Formulation and application details

DDT was available in many different formats including aerosols, dustable powders, emulsifiable concentrates, granules and wettable powders

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

0.006

Low

Solubility - In organic solvents at 20 °C (mg l⁻¹)

1000000

Cyclohexanone

850000

Dichloromethane

770000

Benzene

600000

Xylene

Melting point (°C)

109

Boiling point (°C)

185

Degradation point (°C)

Flashpoint (°C)

Octanol-water partition coefficient at pH 7, 20 °C

8.13 X 10⁰⁶

Calculated

Log P

6.91

High

Bulk density (g ml⁻¹)

0.99

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

0.025

Low volatility

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

8.43 X 10^-01

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)

6200

Very persistent

DT₅₀ (lab at 20 °C)

2000

Very persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Best available data, PIC DGD; DT₅₀; Other sources: DT₅₀ 3 months in tropical regions, 4-30 years temperate regions.

Dissipation rate RL₅₀ on plant matrix

Value

6.0

Note

Published literature RL₅₀ range 1.6-10.8 days, 4 field crops, various matrices, n=5

Dissipation rate RL₅₀ on and in plant matrix

Value

20.2

Note

Published literature RL₅₀ range 3.4-44.0 days, 8 field crops, various matrices, n=13

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

K_d

Non-mobile

K_oc

151000

Notes and range

Log K_oc given as 5.18

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-3.89

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

Key metabolites

Metabolite

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

DDE (Ref: HSDB 1625)

Soil

Not assessed under 91/414 or 1107/2009

DDD (Ref: ENT 4225)

Soil

Not assessed under 91/414 or 1107/2009

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

3173

(Other literature Log BCF values range 1.9-5.5 (R3))

Threshold for concern

CT₅₀ (days)

Not available

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

113

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rat 160 day

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2240

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 2.5

Oncorhynchus mykiss

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.13

Oncorhynchus mykiss

Moderate

Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

> 0.005

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)

> 0.0027

Chironomus riparius 1 day

High

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)

0.54

Apis mellifera

High

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)

0.556

Megachile rotundata

High

Mode of exposure

Contact

Other pollinators (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

0.0074

Nomia melanderi

High

Mode of exposure

Contact

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

> 1000

Eisenia foetida 56 day

Low

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

280

Eisenia foetida as EC10

Low

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

176.0

Folsomia candida as EC10

Other arthropod (1)

LR₅₀ g ha⁻¹

% Effect

Moderately harmful

Typhlodromus pyri

Other arthropod (2)

LR₅₀ g ha⁻¹

% Effect

Soil micro-organisms

Mesocosm study data

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)

113

Rat

Moderate

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

2510

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.01

JMPR 2001

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

JMPR 2000

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

Occupational

European MRLs

EU MRL pesticide database

Drinking Water Standards

Non-statutory WHO drinking water guideline 0.001 mg l⁻¹

UK EA QS database 2018

Drinking Water MAC (μg l⁻¹)

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Highly toxic by ingestion, inhalation and via skin absorption
Strong links with breast and womb cancer
Endocrine issues - Competitive binding to androgen receptors

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

Health: H301, H351, H372
Environment: H400, H410

EC Risk Classification

Carcinogen category 3: R40
T - Toxic: R25, R48/25
N - Dangerous for the environment: R50, R53

EC Safety Classification

S1/2, S22, S36/37, S45, S60, S61

WHO Classification

II (Moderately hazardous)

UN Number

2761

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

DDT

French

DDT

German

DDT

Danish

DDT

Italian

DDT

Spanish

DDT

Greek

DDT

Polish

DDT

Swedish

DDT

Hungarian

DDT

Dutch

DDT

Record last updated:	05/01/2021
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