Copper II hydroxide

Copper II hydroxide	Last updated: 09/04/2025
(Also known as: cupric hydroxide; copper dihydroxide)

SUMMARY

A widely used copper fungicide. It has a low aqueous solubility and a low volatility. As a heavy metal, copper itself will not degrade in the environment. It is moderately toxic to mammals and most biodiversity.

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 Low alert: Non-persistent; GUS: Low leachability; Drainflow: Non-mobile; Potential for particle bound transport: Low	Ecotoxicity High alert: Fish acute ecotoxicity: High; Daphnia acute ecotoxicity: High	Human health Moderate alert: Mammals acute toxicity: Moderate; Reproduction/development effects

GENERAL INFORMATION

Description

Inorganic copper compound used to protect against a number of fungal and bacterial diseases

Example pests controlled

Wide range of fungal pathogens including mildews and leaf spots

Example applications

Fruit including plums, citrus, litchi, mango, apples, pears, grapes; Beans, Peppers, Brassicas, Lettuce, Onions, Curcubits; Tomatoes

Efficacy & activity

Copper based products have been shown to be affective against many fungal pathogens in field trials.

Availability status

Current

Introduction & key dates

1968, registered USA

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/12/2027

GB LERAP status

No data

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

France/Germany

Date EC 1107/2009 inclusion expires

31/12/2025

EU Candidate for substitution (CfS)

Yes - two 'Persistent-Bioaccumulative-Toxic' criteria

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

Morocco

Chemical structure

Isomerism

None

Chemical formula

H₂O₂Cu

Canonical SMILES

[Cu+2].[OH-].[OH-]

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

JJLJMEJHUUYSSY-UHFFFAOYSA-L

International Chemical Identifier (InChI)

InChI=1S/Cu.2H2O/h;2*1H2/q+2;;/p-2/rCuH2O2/c2-1-3/h2-3H

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide; Other substance

Other bioactivity & uses

Bactericide

Substance groups

Inorganic compound

Minimum active substance purity

> 583 g/Kg total copper

Known relevant impurities

EU 2018 dossier: May contain heavy metals including Pb, Cd, As, Ni, CO, Sb & Hg

Substance origin

Natural

Mode of action

Absorbed copper disrupts the enzyme systems of the pathogens. Multi-site activity.

CAS RN

20427-59-2

EC number

243-815-9

CIPAC number

44.305

US EPA chemical code

PubChem CID

30154

CLP index number

029-021-00-3

Molecular mass

97.56

PIN (Preferred Identification Name)

copper II hydroxide

IUPAC name

copper II hydroxide

CAS name

copper hydroxide

Other status information

PAN listed Highly Hazardous Chemical

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

M01

Examples of recorded resistance

Physical state

Blue-green powdery solid

Related substances & organisms

Bordeaux mixture

Formulations

Property

Value

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

Certis Biologicals
BOC Sciences

Example products using this active

Kocide 2000
Kocide 3000

Formulation and application details

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.506

Low

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

0.007

Heptane

0.016

p-Xylene

0.0016

Isopropanol

0.005

Acetone

Melting point (°C)

Decomposes before melting

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

229

Flashpoint (°C)

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

2.75 X 10⁰⁰

Calculated

Log P

0.44

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

3.37

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

0.000001

Low volatility

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

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Acidic soln: 205nm=3605, 250nm=185, 800nm=13, 290nm=32, 295nm=24

Surface tension (mN m⁻¹)

Not applicable

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.1

Non-persistent

DT₅₀ (lab at 20 °C)

0.1

Non-persistent

DT₅₀ (field)

0.1

Non-persistent

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU 2018 dossier: Copper ion rapidly released in soil. Copper is a naturally occurring element and, as such, does not then degrade further. DT₅₀ of Cu >10,000 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

Stable

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

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

K_d (mL g⁻¹)

Non-mobile

K_oc (mL g⁻¹)

12000

Notes and range

Other data source: K_oc 4000-20000 mL g⁻¹ (US3)

Freundlich

K_f (mL g⁻¹)

K_foc (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

0.08

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

Low

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)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 489

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

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

Birds - Acute LD₅₀ (mg kg⁻¹)

223

Colinus virginianus as copper

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)

> 677

Eisenia foetida

Moderate

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

< 15

Eisenia foetida as Cu 56 day

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 12.5 kg Cu/ha

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)

> 44.46

Apis mellifera

Moderate

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

49.0

Apis mellifera

Moderate

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)

55.6% Mortality at dose 0.56 kg Cu/ha

Chrysoperla carnea Adult

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g Cu/ha

Aphidius rhopalosiphi

Beneficial insects (Predatory mites) as Mortality LR₅₀ g Cu/ha

> 148.8

Typhlodromus pyri

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)

0.017

Oncorhynchus mykiss

High

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

0.027

Oncorhynchus mykiss

Moderate

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

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

0.038

Daphnia magna

High

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

0.03

Daphnia magna

Moderate

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)

59.5

Chironomus riparius as mg Cu/kg

Moderate

Aquatic plants (free-floating, growth) - Acute 7 day EC₅₀, biomass (mg l⁻¹)

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

0.009

Pseudokirchneriella subcapitata

High

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

0.003

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)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 489

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.45

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.15

Dog SF=100

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

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

None allocated

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.072

Dermal penetration studies (%)

1-9

concentration dependent

Dangerous Substances Directive 76/464

List II

Exposure Routes

Public

Negligible risk to bystanders for proposed uses

Occupational

Acceptable risk to operators and workers for proposed uses with PPE/PPC

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Statutory EU standard for total copper in drinking water: 2 mg l⁻¹; Non-statutory WHO guideline for total copper in drinking water: 2 mg l⁻¹

UK EA QS database 2018

Drinking Water MAC (μg l⁻¹)

2000

EU Dir 89/778/EC limit as Cu

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Potential heavy metal poisoning

Handling issues

Property

Value and interpretation

General

Prevent generation of dust
Corrosive
Not explosive or oxidising
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H301, H332

WHO Classification

II (Moderately hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

Limited shelf-life. Store at 0-6 DegC

TRANSLATIONS

Language

Name

English

copper II hydroxide

French

hydroxyde de cuivre

German

Kupferhydroxid

Danish

kobberhydroxid

Italian

idrossido di rame

Spanish

hidróxido de cobre

Greek

Polish

wodorotlenek miedzi (II)

Swedish

kopparhydroxid

Hungarian

réz(II)-hidroxid

Dutch

Norwegian

Record last updated:	09/04/2025
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