Copper (I) oxide

Copper (I) oxide	Last updated: 31/10/2024
(Also known as: cuprite; dicopper oxide; copper oxide; red copper oxide; cuprous oxide)

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.

GENERAL INFORMATION

Description

An inorganic compound used as a mineral supplement for livestock

Availability status

Current

Introduction & key dates

1943, generally introduced; 1998, approved for non-food applications in US

Examples of veterinary uses

Used for the prevention and treatment of copper deficiency in livestock

Examples of species treated

Sheep; Cattle

Approval status

VMR 2013/2033 approval status (GB/UK)

Approved

EU Regulatory approval status

Approved

Chemical structure

Isomerism

None

Chemical formula

Cu₂O

Canonical SMILES

[Cu].[Cu].O

Isomeric SMILES

International Chemical Identifier key (InChIKey)

BERDEBHAJNAUOM-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/2Cu.O/rCu2O/c1-3-2S

2D structure diagram/image available?

Yes

General status

Veterinary substance type

Mineral supplement

Substance groups

Inorganic compound

Minimum active substance purity

858 g kg⁻¹ 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

Protective, inhibiting fungal spores and pathogens from entering the host tissues. Multi-site activity.

Molecular targets

CAS RN

1317-39-1

EC number

215-270-7

CIPAC number

44.603

US EPA chemical code

PubChem CID

14830

CLP index number

029-002-00-X

Therapeutic Class

Alimentary tract and metabolism: Mineral supplements

ATCvet Code

QA12CX

Controlled Drug?

Regulation 37/2010 MRL Classification

Allowed substance (Table 1: All food producing species)

Molecular mass

143.08

PIN (Preferred Identification Name)

IUPAC name

dicopper oxide

CAS name

cuprous oxide

Other status information

Relevant Environmental Water Quality Standards

Physical state

Brownish red to orange coloured powdery solid

Formulations

Property

Product

Manufacturer

Authorisation Route

Legal Class (GB/UK)

Example products (past and present) using this active

Copasure 24g Capsule

Animax Ltd

UK National authorisation

Authorised veterinary medicine for general sale (AVM-GSL)

Copinox Ewe/Calf Capsule

Animax Ltd

UK National authorisation

Authorised veterinary medicine for general sale (AVM-GSL)

Copinox lamb 2g hard capsule

Animax Ltd

UK National authorisation

Authorised veterinary medicine for general sale (AVM-GSL)

Formulation and application details

Usually supplied in capsule form

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.64

Low

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

0.000014

Toluene

0.00001

Dichloromethane

0.000098

n-Hexane

0.000012

Ethyl acetate

Melting point (°C)

Decomposes before melting

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

400

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)

6.0

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

1.00 X 10^-10

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=2978, 250nm=1425, 800nm=40, 290nm=265, 295nm=198

Surface tension (mN m⁻¹)

Not applicable

Refractive Index

Environmental release

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.1

Non-persistent

DT₅₀ (lab at 20 °C)

0.1

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

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

Manure DT₅₀ (days)

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)

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)

K_oc (mL g⁻¹)

Notes and range

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

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)

> 300

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)

1183

Coturnix japonica

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)

> 862

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: 15.0 kg Cu/ha; 28 Day

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)

> 22.0

Apis mellifera

Moderate

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

> 116

Apis mellifera

Low

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 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)

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

39200

Aphidius rhopalosiphi

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

26100

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)

0.207

Oncorhynchus mykiss

Moderate

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

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

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

0.45

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)

0.057

Americamysis bahia

High

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 - Acute 7 day EC₅₀, biomass (mg l⁻¹)

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

0.147

Pseudokirchneriella subcapitata

Moderate

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

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)

> 300

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

2.92

Rat 4 hr (nose only)

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

Rat SF=30

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

Mammalian dose elimination route and rate

Excess copper is excreted in the bile, only small amounts being found in urine

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

, ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Potential heavy metal poisoning
Kidneys, lungs and liver toxicant
Harmful if swallowed

Handling issues

Property

Value and interpretation

General

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

CLP classification 2013

Health: H302, H332, H318

WHO Classification

II (Moderately hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

copper (I) oxide

French

cuivre de l'oxyde cuivreux

German

Dikupferoxid

Danish

kobberoxid

Italian

ossido di rame

Spanish

oxido de cobre

Greek

Polish

tlenek miedzi (I)

Swedish

koppar(I)oxid

Hungarian

Dutch

koper(I)oxide

Norwegian

kopper(I)oksid

Record last updated:	31/10/2024
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