6. Safety, PPE and avoiding risks (techniques, formulations, etc.)

CropLife Workshop on Better Application in Asia

v. 10 September 2017

Early (1990s) guide to responsible use for farmers!

Safety issues

Operator

Environment

Assessing and Understanding risks

Risk / Hazard

No use + no hazard = no risk

Use (exposure) + no hazard = no risk (rare!)

Use * hazard = risk

Personal Protective Equipment (PPE)

“full protective clothing should always be worn when using pesticides”

Personal Protective Equipment (PPE)

• Cloth or disposable face masks are usually considered inadequate for pesticide spraying.

• EU specifications – depend on product, but requires full filtration and /or face visor

• PPE should NEVER be considered the first line of defence:

Spraying procedures (techniques)

Engineering controls

Making a face visor

commercial visors expensive: may cost >€/$ 20

construct your own face shield:

2 L plastic (not ribbed) soft drinks bottle

Plastic foam headband; tied on with strings.

Co

urt

esy

INIA

P, E

cuad

or

• Wear comfortable clothing that protects as much of the body, arms and legs as possible.

Prevention (of exposure) before appropriate PPE

… and Prevention is better than Cure

wind PPE must not be the first line of

defence against exposure

learn how to spray and maintain

equipment correctly:

always keeping the nozzle down-wind

regularly check equipment and repairs for

leaks

select the least toxic products.

Start spraying down-wind and always keep the nozzle down-wind

At the end of each track, change hands for holding the lance to keep nozzle(s) down-wind ‘Rainbowing’ is neither safe nor efficient as a method of spraying

WIND Track

spacing

Hygiene and Clothing • Never put on previously

contaminated overalls or other clothing

• Wash work clothing after each day’s use

• … but away from water sources.

Acute Toxicity: classification and colour coding

Class Solids Liquids

oral dermal oral dermal

Ia Extremely Hazardous 5 10 20 40

Ib Highly Hazardous 6-50 11-100 21-200 41-400

II Moderately Hazardous 51-500 101-1000 201-2000 401-4000

III Slightly Hazardous ≥ 501 ≥ 1001 ≥ 4001

IV (U) Unlikely to present

acute hazard in

normal use

≥ 2001 - ≥ 3001 -

≥ 2001

World Health Organisation (US EPA) (LD50 of formulations to rats: mg/kg body weight)

>40 standard pesticide Formulations …

Terminology CropLife International* / FAO

2-letter convention: e.g. WP, WG, GR

…including:

AI - Active Ingredient

TC - Technical material

* Catalogue of Pesticide Formulation Types (Technical monograph 2):

http://croplife.org/resources/

Some common formulations

Applied as liquid sprays:

SL, SP WP EC SC WG

For mixing and spraying with water

Formulation types by use

ULV UL, OF

Usually used undiluted (or limited dilution with organic carrier)

Fogging: HN, KN

Miscellaneous others

PO - pour on (animals)

GS - grease

etc.

DP GR MG

Dry

Seed treatments

Fumigants and smokes

Formulations for baiting

Water miscible formulations

Older formulations:

Emulsifiable concentrate EC

Wettable powder WP

Soluble (liquid) concentrate SL

Soluble powder SP

Reducing hazards (and use of solvents),

improved stability:

Suspension concentrate SC

Capsule suspensions CS

Water dispersible granules WG

Micro-emulsions ME

Pesticide labels: precautionary phrases, etc

• PPE

• environmental safety

• resistance

• compatibility with other products

Use of pictograms

What do these warning signs mean?

very toxic harmful /

irritant

danger

to the

environment

corrosive health

hazard

• … and storage

Pictograms for Safe Handling

• Spray drift and other environmental concerns

• Storage, disposal of packaging, etc.

• … and the public (including our families!) …

• For the farmer: costs (including work rate)

Other issues to consider

Environmental fate: sources of contamination …

Atmosphere

spray drift

evaporation

precipitation,

dry deposition

short & long-

distance

transport

point source

contamination

diffuse

contamination

crop run-off

(endo-drift)

drainage

land

run-off

water sources

Application

of pesticide

leaching seepage

ground-water

Deposition

on target

What is important?

• exo-drift (the transfer of spray out of the target area)

• endo-drift, where the a.i. in droplets falls into the target area, but does not reach the biological target. – Endo-drift is volumetrically more significant

– Might “exo-drift” be reduced at the expense of an increase in “endo-drift”?

• Point source contamination – Containers, sprayer washing → water courses

Himel (1974)

Disposal of Containers

• Safety: especially to animals & children

• Prevent contamination of the environment - especially water courses

• Practical: – Triple/pressure rinse, pour

rinsate into sprayer

– Leave packaging in the field

– Bury, burn containers

– Puncture containers

– Safe disposal scheme (stores) *

Disposal: a practical example (vegetable cooperative)

initiatives (including research): Multi-trip, returnable containers one-way, single-trip containers: recyclable materials

https://croplife.org/crop-protection/stewardship/container-management/