Silver sodium thiosulphate

Silver sodium thiosulphate	Last updated: 23/08/2018
(Also known as: sodium silver thiosulphate; sodium silver thiosulfate; silver sodium thiosulfate; SST)

SUMMARY

Silver sodium thiosulphate is a silver complex used as a post-harvest conditioner. A non-volatile aqueous solution of silver and thiosulphate ions. No significant human health concerns identified. No significant environmental concerns highlighted relateddirectly to its use however wastes must not reach the public sewer as there is a risk to terrestrial biodiversity from contaminated sewage sludge. Highly toxic to aquatic life and soil invertebrates.

GENERAL INFORMATION

Description

A plant growth regulator used commercially to prolong the life of cut flowers particularly useful for those sensitive to ethylene

Example pests controlled

Example applications

Ornamentals - cut flowers

Efficacy & activity

Availability status

Current

Introduction & key dates

UK regulatory status

UK approval status

Not approved

EC Regulation 1107/2009 (repealing 91/414)

EC Directive 91/414 Status

Approved

Dossier rapporteur/co-rapporteur

Netherlands

Date inclusion expires

30/04/2024

EU Candidate for substitution (CfS)

Listed in EU database

Yes

Approved for use (✓) or known to be used (#) in the following EU-27 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

Chemical formula

[Ag(S₂O₃)₂]₃-

Canonical SMILES

Isomeric SMILES

International Chemical Identifier key (InChIKey)

International Chemical Identifier (InChI)

2D structure diagram/image available?

General status

Pesticide type

Plant growth regulator, Anti-senescent

Substance group

Solution of ratio 1:8 silver to thiosulphate ions

Minimum active substance purity

10 g Ag kg⁻¹ as Ag

Known relevant impurities

Substance origin

Synthetic

Mode of action

CAS RN

None

EC number

None

CIPAC number

762

US EPA chemical code

080119

PubChem CID

No data

Molecular mass

332

Chemical name

silver sodium thiosulphate

PIN (Preferred Identification Name)

IUPAC name

CAS name

Other status information

Contains silver nitrate

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Not applicable

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Physical state

Transparent liquid

Formulations

Property

Value

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

Chrysal aVB

Example products using this active

Chrysal International

UK LERAP status

Not applicable

Formulation and application details

Usually supplied as a soluble concentrate formulation

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

Not applicable

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

Not applicable

Melting point (°C)

-22

Freezing point

Boiling point (°C)

100

Degradation point (°C)

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

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

Log P

Bulk density (g ml⁻¹)

1.144

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C

Henry's law constant at 25 °C

GUS leaching potential index

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

Cannot be calculated

Note

Potential for particle bound transport index

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

Max @ 277.6nm

Surface tension (mN m⁻¹)

72.0

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

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

K_d

84000

K_oc

Notes and range

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Birds - Acute LD₅₀ (mg kg⁻¹)

Birds - Short term dietary (LC₅₀/LD₅₀)

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

0.0056

Pimephales promelas as AgNO3

High

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.00024

Oncorhynchus mykiss as AgNO3

High

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

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

0.0016

Daphnia magna as AgNO3

High

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 (Apis 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)

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)

Mode of exposure

Other pollinators (2)

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

Mode of exposure

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

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

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

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

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

0.006

Rat SF=100 as SST

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

None allocated

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

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

0.006

Rat SF=100 as SST

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Occupational

European MRLs

EU MRL pesticide database

Drinking Water Standards

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

Possinle gastro-intestinal toxicant

Handling issues

Property

Value and interpretation

General

Careful disposal of wastes required - do not permit substance to reach sewer system

CLP classification 2013

EC Risk Classification

T - Toxic: R33
N - Dangerous for the environment: R50/53

EC Safety Classification

WHO Classification

NL (Not listed)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

silver sodium thiosulphate

French

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Danish

Italian

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Record last updated:	23/08/2018
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