Dr. Aidan Moody presentation - iasis.ie

IASIS Conference
Killenard, 3 February 2011
Pesticides and Water
Exposure Assessment, Monitoring & Controls
Aidan Moody
Pesticide Registration & Control Division

Contents
• Introduction
• Groundwater exposure assessment
• Surface water exposure assessment
• Water Framework Directive
• Di Drinking water monitoring
i
• Minimising exposure
• Conclusions

Introduction
Exposure assessment requirements
Environmental Science Unit
Environmental Fate
Ecotoxicology
Predicted Environmental Concentration (PEC)
• Groundwater
• Surface water (and sediment)
• Directive 91/414/EEC (S.I. No. 83 of 2003)
• Regulation (EC) No 1107/2009

Groundwater
• Groundwater is an important source of drinking
water.
• Provides ~9% of Irish drinking water
(over 80% in Roscommon).
• For pesticide approval, PEC in groundwater must
not exceed 0.1 microgram/L.

Groundwater
• 0.1 microgram/L = 0.1 ppb
(1 part in 10 billion)
• Equivalent to one drop in an Olympic-sized
swimming pool!
(1 stem in 111,000 hay bales, 1 baked bean in 21
million cans)
• Not a health-based standard
(Political decision from 1980 to use 0.1 ppb as a
surrogate for zero.)

Groundwater
• EU leaching models used to calculate PEC in
groundwater (diffuse pollution).
• Models use Good Agricultural Practice (GAP) for
pesticide product, chemical properties of active
ingredient, and EU-defined leaching scenarios.
• Scenarios are combinations of –
weather data
soil properties
crop information.
• Aim is to calculate realistic worst-case PEC
(at 1 m depth below the soil surface).

Groundwater
Leaching – downward movement of pesticides in water through soil

Surface water
• Assess exposure in edge-of-field water bodies:
ditches, streams, ponds.
• PEC in surface water and sediment must not be
harmful to aquatic life forms.
• Aquatic risk assessment performed.
Risk = Adverse-effect level/PEC
Margin of safety must be acceptably high.
• Aim is to protect ecology of water bodies
(science-based protection goal).

Surface water
• EU aquatic exposure models used to
calculate PEC in surface water and
sediment (diffuse pollution).
• Models use –
GAP for pesticide product
chemical properties of active ingredient
EU-defined aquatic exposure scenarios.
• Aim is to calculate realistic worst-case PEC.

Surface water
Key entry routes: spray drift, drainage, runoff

Surface water
• Drainage
Removal of surplus water from land to surface water by the
use of within-field drains.
• Runoff
Transport of water and sediment from the surface of an
agricultural field, by overland flow, to a non-target area
such as a stream, due to a precipitation event.
• Spray drift
Downwind movement of airborne spray droplets beyond
the intended area of application, originating from spraying
operations.

Buffer zones
Surface water
Outcome of assessment may require a buffer
zone (untreated area) to reduce spray drift
and/or runoff input (e.g. 5 m grassed strip).

WFD
Water Framework Directive (Directive 2000/60/EC)
• Prevent deterioration in the status of surface
waters, groundwater bodies, estuaries and
coastal waters.
• Aim to achieve good status in WFD water bodies
by 2015.
• Catchment-based approach
River Basin Districts
(instead of edge-of-field)
field)
• Rivers and lakes
(rather than ditches, streams and
ponds)

WFD
Irish River Basin Districts (RBDs)
8 RBDs Authorities
Neagh Bann IRBD
North Western IRBD
Shannon IRBD
North Eastern RBD
Eastern RBD
South Eastern RBD
South Western RBD
Western RBD
Monaghan / DOE NI - NIEA
Donegal / DOE NI - NIEA
Limerick
DOE NI - NIEA
Dublin City
Carlow
Cork
Galway

WFD
Lead agencies in Ireland
• DEHLG
• EPA
• Local authorities
Other government departments and agencies involved
(DAFF, DETI, Central Fisheries Board, Teagasc,
Waterways Ireland etc.)
See www.wfdireland.ie for more info.

WFD
Two main areas of concern for pesticides
• River Basin Management Plans
(controls on pesticide use)
• Monitoring programmes
(compliance with EQS values)

River Basin Management Plans (RBMPs)
Measures for pesticides include –
• GAP (Good Agricultural Practice)
• Sustainable Use National Action Plans
• Supplementary measures for forestry
(reduce usage, pre-dip plants, develop
biological controls)
Future measures could include
restricting/prohibiting pesticide use in
designated areas if there is a problem.
WFD
WFD could impact on regulatory status of pesticides.

Sustainable Use Directive – 2009/128/EC
WFD
• Reduce risks and impacts of pesticide use on human
health and the environment.
• Focus on protection of aquatic environment and
drinking water supplies.
• Measures to protect aquatic environment and drinking
water supplies must be compatible with the WFD.
• Possible mitigation measures for National Action Plan –
buffer zones (aquatic environment)
safeguard zones (drinking water abstraction points).
SU NAP ill b th i t
SU NAP will be the main measure to
deliver WFD pesticide-related objectives.

WFD monitoring
• National programme covering surface waters and
groundwater.
• Administered by EPA.
• Results will be made available on EPA website –
www.epa.ie/whatwedo/wfd/monitoring/results
WFD
• Groundwater monitored at 145 sites for –
2,4-D, atrazine, bentazone, chlorotoluron,
cypermethrin, DDT, dieldrin, diuron, glyphosate,
isoproturon, lindane, MCPA, mecoprop and simazine.
• Groundwater results compared against threshold
level of 0.1 microgram/L.

WFD
WFD surface water monitoring
• EU-specified substances and additional national substances.
• EU-specified pesticides –
alachlor, aldrin, atrazine, chlorfenvinphos, chlorpyrifos, DDT,
dieldrin, diuron, endosulfan, endrin, hexachlorocyclohexane,
isodrin, isoproturon, pentachlorophenol, simazine and
trifluralin.
• National pesticides monitored by Ireland in first phase –
2,4-D, dichlobenil (and its metabolite BAM), epoxiconazole,
glyphosate, linuron, malathion, mancozeb, maneb, mecoprop,
pirimiphos-methylmethyl and zineb.

WFD
WFD surface water monitoring
• Results compared against Environmental Quality Standards
(EQS values)
• EU-specified pesticides
Comparison against EU EQS values (Directive 2008/105/EC).
• National pesticides
Results compared against national EQS values.
• National EQS values (S.I. 272 of 2009) established for –
dimethoate, glyphosate, linuron and mancozeb.
EQS is cut-off point for designation of good chemical status.

Drinking water
Monitoring of tap water
• Drinking Water Directive – 98/83/EC
(S.I. No. 278 of 2007)
• Conducted by local authorities.
Results reported to EPA
• Responsibility of local authorities to decide
which pesticides to monitor, and to organise
sampling and analysis.
• Drinking water standard for individual
pesticides = 0.1 microgram/L.

Issues to consider
• Agricultural use of pesticides
Drinking water
• Amenity uses
(parks, sports grounds, golf courses, roadside verges)
• Amateur use
(home gardens)
• Substances most likely to be detected are high-use,
water-soluble and relatively persistent in water.

Drinking water
Prevention better than treatment
t t
One foil seal contains enough pesticide
to breach 0.1 microgram/L level along 30 km
of a typical stream (width = 1 m, depth = 0.3 m)

Drinking water
Prevention better than treatment
• Local authorities required to take remedial action
if there is an ongoing problem.
• Source control measures
Restrict/prohibit pesticide use in affected areas.
• Removal options
Fit water treatment plants with activated carbon
adsorption filters (very expensive).
Potential for regulatory action in event of an ongoing problem.

Minimising exposure
Diffuse pollution (sprayer use)
Entry routes - spray drift, drainage, runoff, leaching

Minimising exposure
Point source pollution (pesticide handling areas)
Entry routes – mixing, filling, washing, spillage, leaks

Minimising exposure
Diffuse pollution
• Follow the label instructions (buffer zones).
• Be aware of location of water bodies and if they are
used to supply drinking water.
• Do not apply if heavy rain forecast within 48 hours.
• Do not apply to saturated or frozen ground.
• Do not apply if field drains are flowing.
• Do not apply on areas with channels that drain
directly to water.
• Do not apply to dry, cracked soils.

Minimising exposure
Diffuse pollution
• Do not apply on poorly draining or wet soils that
slope strongly towards a water body.
• Consider grassed buffer strip to protect vulnerable
water bodies.
• Ensure application equipment is properly calibrated.
• Do not spray in windy conditions.
• Keep spray boom as low as possible.
• Use the coarsest appropriate spray quality.
• Consider use of drift-reducing nozzles.
• Consider alternative ti treatments.
t t

Minimising exposure
Point source pollution
• Follow the label instructions.
• Be aware of location of water bodies and if they are
used to supply drinking water.
• Perform handling operations well away from water
bodies and from drains (10-50 m).
• Consider using a containment system to catch spills
(e.g. a bund or lip around filling area).
• Minimise water volumes (rain and washings) on
handling area.

Minimising exposure
Point source pollution (sprayer washdown)
• Best practice for tank washings and sprayer
exterior surfaces is to carry this out in the field.
• Any washings should be discharged onto the
previously sprayed cropped area.
• Observe maximum dose for that area.

Minimising exposure

Conclusions
• Regulatory assessment of groundwater and surface water
exposure uses EU standard models and scenarios.
• Groundwater exposure compared to drinking water standard
(0.1 microgram/L).
• Aquatic risk assessment performed for surface water (buffer
zone may be required).
• Main surface water input routes: spray drift, drainage, runoff.
• WFD uses a catchment-based approach (River Basin
Districts).
• Sustainable Use National Action Plan will be main measure
to deliver WFD pesticide-related objectives (potential impact
on regulatory status of pesticides).

Conclusions
• WFD monitoring covers surface waters and groundwater
(national programme administered by the EPA).
• Surface water monitoring for EU-specified pesticides and
national pesticides (results compared to EQS values).
• Drinking water monitoring carried out by local authorities.
• Local authorities decide which pesticides to monitor.
• Prevention of drinking water exposure better than treatment.
• Necessary to minimise exposure from diffuse pollution and
from point source pollution.
• Follow label instructions and other available advice, and use
common sense.

Thank you for your attention
www.pcs.agriculture.gov.ie
E-mail: pcs@agriculture gov ie
E-mail: pcs@agriculture.gov.ie
aidan.moody@agriculture.gov.ie
Phone 01-6157625 (direct line)