The Manner of Application of Pesticides
by
Brenda J Rosser

Senate Question Number 1046
Answer to Question a.	What information does the Government have and what is its understanding of the ability for spray to drift beyond target land?
Comments on the two documents referenced by Senator Ian McDonald
1.	The Primary Industries Standing Committee (PISC) Report No 82, entitled “Spray Drift Management – Principles, Strategies and Supporting Information” 2003
(i)	No current mechanism exists to define buffer distances for pesticide drift control
(ii) All commercial nozzles generate a range of droplet sizes
(iii) Many (most) droplets from current operations are small and prone to drift in air currents
(iv) Each metre of release height results in a very dramatic rise in pesticide drift
(v)	APVMA sets a spurious release height of 15 metres for forestry ops
(vi) Aircraft should be straight and level above the crop. How is this possible in Tasmania?
(vii)	The atrocious scale of aerial spraying in Australia
(viii) The number of chemicals used makes them impossible to monitor
(ix) Affected neighbours have little power
(x) No alternatives to pesticide use presented nor referred to
(xi)	Lack of mandatory requirements
(xii)	Compelling Evidence that Tassie’s Spray Exclusion Zones are Dangerous!
(xiii) Aerial spraying over hilly terrain
a.	No drift modelling for aerial spraying in hilly terrain. Why not?
b.	Aircraft needs to be straight and level when spraying?
c.	Hills create air turbulence
(iixx)  ‘Acceptable’ dose of pesticide drift is being set without adequate science or consultation
a.  Limits to the science of toxicology
b.  General lack of toxicity data
c.  MRLs in Australia are set much higher than elsewhere:
Obstruction by the Tasmanian Spray Complaints Unit
2.  "Operating Principles and Proposed Registration Requirements in Relation to Spray Drift Risk"
Public asked to comment without access to spray drift modelling data
The APVMA assumes responsibility for how registered chemical products may be used
The APVMA increased the proposed release height for aerial spraying from 3 metres to 15 metres
Answer to Question (b): has the possibility of drift over distances of kilometres beyond target land been dismissed; if so, how and by whom; if not; what safety standards have been instigated or put in place by relevant Government departments and agencies.

Senate Question Number 1046
On 3rd August 2005, Bob Brown asked, on notice, the Minister representing the Minister for Agriculture, Fisheries and Forestry Senator Ian MacDonald the following questions:

“With reference to aerial spraying of chemicals on Australian crop lands:

a.	what information does the Government have and what is its understanding of the ability for spray to drift beyond target land; and

b.	has the possibility of drift over distances of kilometres beyond target land been dismissed; if so, how and by whom; if not; what safety standards have been instigated or put in place by relevant Government departments and agencies.”

Senator Macdonald provided the following answers:
Answer to Question a.	What information does the Government have and what is its understanding of the ability for spray to drift beyond target land?

Senator Macdonald said:  
"The Primary Industries Standing Committee (PISC) Report No 82, "Spray Drift Management - Principles, Strategies and Supporting Information, published in 2003, is a comprehensive document which draws together current scientific and technical information on the causes of chemical spray drift and ways to reduce it for both ground and aerial spraying. A copy of the PISC Report is available from the Senate Table Office.

The Australian Pesticide and Veterinary Medicines Authority (APVMA) has recently published a discussion paper entitled "Operating Principles and Proposed Registration Requirements in Relation to Spray Drift Risk" which references the PISC Report. The discussion paper outlines the APVMA's proposed approach to improving spray drift assessment and risk management and is available on the APVMA's website for public consultation until 21 October 2005. The APVMA is also developing additional information on risk factors which will be included on its website under "Spray Drift Considerations".

There is always a possibility of chemical spray drift occurring whenever pesticides are sprayed, even when applied with care.”
Comments on the two documents referenced by Senator Ian McDonald
1.	The Primary Industries Standing Committee (PISC) Report No 82, entitled “Spray Drift Management – Principles, Strategies and Supporting Information” 2003
http://downloads.publish.csiro.au/books/download.cfm?ID=3452
(i)	No current mechanism exists to define buffer distances for pesticide drift control
This document outlines a multitude of factors that influence pesticide drift.  Things such as wind speed, wind direction, humidity, spray release height, existence of inversions and wind turbulence (See page 4, Section 1.2).  However, droplet size is a major factor.  But there is currently no standardised spray nozzle selection and utilisation in Australia.  The document states that (page 38) IF a nozzle classification system is fully adopted by the Australian industry, then this will allow “manufacturers and regulators not only to describe spray quality and thus nozzle systems for particular uses, but also to provide a mechanism for defining buffer distances for pesticide drift control.”

Given the multitude of other factors (apart from droplet size as a function of the type of spray nozzle used) that influence the extent of drift the document provides no clear explanation as to how a mere standardisation of nozzles will adequately define the required buffer distances between spraying operations and sensitive areas.  

The document continues this vagueness by saying, on page 3 “If sensitive areas are present or become established within the [drift] awareness zone, details should be recorded and, if necessary, expert advice sought.”  There is no explanation as to what ‘if necessary’ means. And experts, with no clearly defined educational criteria, are expected to be of assistance in defining individual buffers when the aerial spraying operator chooses to do so.  
                    (ii) All commercial nozzles generate a range of droplet sizes
On page 38 it says that 10 micrometre droplets “may be considered essentially airborne”.  In the next paragraph it is stated that there is “no practical spray nozzle system used in agriculture [that] produces droplets that are all the same size.  All commercial nozzles generate a range of droplet sizes.”  On page 39, Figure 13 provides a “typical droplet spectra” that clearly shows a range of droplet sizes from 10 micrometres to approximately 375 micrometres. On page 41, large droplets are defined as 300 micrometre and small droplets anything less than that. So the graph (on page 39) clearly demonstrates that most droplets are small in size. 
       (iii) Many (most) droplets from current operations are small and prone to drift in air currents
Page 38:  “Vertical and horizontal air movement must be appreciated to understand fully the droplet transport process.  When droplets are large (eg >300 micrometre) their passage towards the ground from spray equipment is largely influenced by gravitational forces.  In other words, the droplets tend to impact on the ground largely unaffected by air currents, unless the wind velocities are very large.  However, many droplets produced by spray equipment are smaller than 300 micrometres.  As droplets decrease in size, their movement becomes increasingly controlled by the movement of air around them..”

On page 45 it is made clear that the nozzles currently in use by the industry are far from optimal.  “Hydraulic nozzles are the most common type of nozzle found in ground application equipment.  A hydraulic nozzle has to meter liquid flow, generate a specified droplet size range and direct the spray in a desired direction and pattern.  While their limitations (primarily the wide range of droplet sizes that are produced) have long been recognised, their simplicity, robustness and cost have led to their widespread adoption by Australian growers…”  and “hollow cone nozzles are generally operated at higher pressures and may produce small droplets than flat fan nozzles, which are more appropriate for foliage spraying.  There has been a general trend away from hollow cone to flat fan nozzles for many types of pesticide application because flat fan nozzles are capably of applying more uniform deposits over the area to be treated…”

NOTE:  a quick search on the web indicates that the forest industry uses hydraulic nozzles for aerial spraying.  See:  http://www.fao.org/documents/show_cdr.asp?url_file=/docrep/007/y5507e/y5507e07.htm
And
“the two main types of atomisers used in aerial systems are hydraulic spray nozzles and rotary atomisers..”
http://www.pmra-arla.gc.ca/english/pdf/edu/edu_aerial-e.pdf
(iv) Each metre of release height results in a very dramatic rise in pesticide drift
The last graph in Figure 21 on page 57 shows a steep rise in pesticide drift 500 metres downwind of aerial spraying.  
(v)	APVMA sets a spurious release height of 15 metres for forestry ops
At a 15 metre height (that recommended by the APVMA for forestry spraying operations – see www.apvma.gov.au/users/spray_drift_risk.pdf) the downwind deposit at half a kilometre is 5% of the applied rate.  This computer modelling does not take into account a whole range of factors that would exacerbate this problem such as humidity, turbulence, speed of helicopter etc.  Instead the modelling assumes ideal and linear conditions that could not take into account the complexity of real world situations.  The APVMA has failed to provide any modelling of aerial spraying drift at 15 metres beyond the single and alarming graph in Figure 21, page 57 of this document.

NOTE:  Current forestry aerial spraying more often than not exceeds 15 metres.  From my observations the helicopter is usually about 30-40 feet above the canopy but I have also seen spraying done where the helicopter was closer to 300 feet above the ground.  *Spray release heights become somewhat irrelevant when the helicopter (as it often is) is on top of a hill or at a very high altitude compared with the rest of the surroundings.
   (vi) Aircraft should be straight and level above the crop. How is this possible in Tasmania?
On page 54 it is recommended that large droplet placement application requires that “aircraft are positioned straight and level above the crop” with the wheel height not exceeding 3 metres above the crop during spraying.

Tasmania’s forestry terrain is hilly.  Where there are plantations they are often interspersed with small strands of larger and older native trees along the creeks and rivers.  It is typical for plantations to be broken up repeatedly by creeks, dams and rivers leaving very small areas of land (very often only a hectare or two) that are flat enough to allow an aeroplane to be positioned straight and level.  It’s simply impossible to keep a plane straight and level in the type of topography found where tree plantations grow in this state.
(vii)	The atrocious scale of aerial spraying in Australia
On page 48 in section 2.6.8 entitled ‘Aerial Spraying’ it says:  “There are currently about 300 aircraft registered in Australia for the application of pesticides.  These specialist aircraft, flown by pilots from about 100 aerial application companies, apply pesticides and fertilisers to about 10 million hectares annually (under average to good seasonal conditions).
(viii) The number of chemicals used makes them impossible to monitor 
On page 48 in section 2.6.8 entitled ‘Aerial Spraying’ it says:  “There are approximately 1,100 pesticides registered for agricultural purposes in Australia, of which approximately 370 are registered for aerial application.

How can any regulatory or health authority measures the level of contamination in fresh water when they have to test for so many chemicals.  There appears to be no consideration given for the synergistic effects of chemical combinations in the environment and in our bodies.  

Residues of 36 different types of pesticides were found in a range of commonly eaten foods in Australia. (The 20th Australian Total Diet Survey, 2003, carried out by Foods Standards Australian New Zealand FSANZ).
(ix) Affected neighbours have little power
Legal action against the offending and careless forestry industrialists and farmers appears to be the major recourse available.  This is prohibitively expensive.  A number of Tasmanians are currently involved in an appeal to the Forest Practices Tribunal to try and stop several private timber reserves at Reedy Marsh.  This is a test case.  The arguments put forward are on the basis of whether (a) the land is suitable for a Private Timber Reserve, and (b) whether the private timber reserves are in the ‘public interest’.  The procedures to-date have been flawed and markedly in favour of Gunns Ltd.

The ‘Principles and Strategies’ document rarely mentions any mandatory requirements.  The document is full of ‘should bes’ and ‘encouraged to’.  Spraying plans ‘should be’ communicated to neighbours. No mention of consultation with those directly affected by spray drift.  (See page 1).
(x) No alternatives to pesticide use presented nor referred to
On page 8, Section 1.4.  “alternative pest control..should be considered”.  The obvious flaw in forestry, with respect to the establishment of a vast tree monoculture (in terms of pest vulnerability) is not mentioned. No references are made as to where alternatives can be found.
(xi)	Lack of mandatory requirements
No mandatory requirements for the following drift mitigation strategies:
•	Weather conditions (see page 9)
•	Neighbour consultation and communication (page 1)
•	Establishment of drift awareness zones (page 3)
•	Establishment of adequate buffer zones apart from a woolly reference to ‘duty of care’ in the (voluntary) aerial spraying code of practice.
•	Exploration of alternatives to chemicals. (Page 4)
•	Height of spray release (page 14)
•	Adequate boom stabilisation.
•	Choice of spray nozzle.
•	Spraying in hilly terrain.
•	Provision of spray drift modelling.
•	Adequate record keeping
•	Public access to spray records
(xii)	Compelling Evidence that Tassie’s Meagre Spray Exclusion Zones are Dangerous!
In Tasmania the (voluntary) aerial spraying code of practice sets a minimum spray exclusion zone around a dwelling of 100 metres.  Around a creek or dam it is a mere 10 metres.  

The forestry and agricultural industry uses these minimum distances as their standard everyday practice, unless they are instructed otherwise (and that rarely occurs).  This distance flies in the face of evidence from existing spray drift modelling where it could be argued (successfully) that aerial spraying should not ever be considered in rural residential areas close to homes, schools, school bus stops, shops and endangered species.

On page 3, Section 1.1:  “The chemical user should be responsible for establishing a spray drift awareness zone around the property.  Under most circumstances, the awareness zone for ground spraying could extend from approximately 100 metres to 1 kilometre from the paddock to be sprayed and up to 5 kilometres from the paddock for aerial spraying.  The width of the awareness zone may be extended if there are special sensitive areas nearby or the area is subject to local meteorological effects, such as cold air drainage in a valley (katabatic wind flows)…The zone should be used to aid the survey of areas or buildings outside a field to be sprayed that may be potentially sensitive to spray drifts, eg schools, dwellings, wetland areas, travelling stock routes, organic farms, etc. (Figure 1). 
(xiii) Aerial spraying over hilly terrain
This practice is fraught with dangers:
a.	No drift modelling for aerial spraying in hilly terrain. Why not?
b.	Aircraft needs to be straight and level when spraying?
On page 54 it is recommended that large droplet placement application require that “aircraft are positioned straight and level above the crop”. 

Hills are very frequent in the very areas where aerial spraying is most common in Tasmania – the North West and North East coastal hinterland. Often there is only a hectare or two that are flat enough to allow an aeroplane to be positioned straight and level.  It’s simply impossible to keep a plane in that position whilst spraying in the type of topography found here.
c.	Hills create air turbulence
Page 3:  “The width of the awareness zone may be extended if there are special sensitive areas nearby or the area is subject to local meteorological effects, such as cold air drainage in a valley (katabatic wind flows).  On page 20 it says (in terms of establishing drift awareness zones):  “Small distances (eg. 100m) might be appropriate for spraying small horticultural areas with hand-held equipment, whereas large distances (eg. 5km) might be required for aerial application of agricultural chemicals in large monocultures.”

The document further adds an ‘Important note’ saying “The establishment of a drift awareness zone at a given distance does not imply that spray droplets can or cannot be transported in air beyond that distance.”
(iixx)  ‘Acceptable’ dose of pesticide drift is being set without adequate science or consultation
On page 30, Section 2.4.4:  “While following label directions will not necessarily prevent spray drift, it is a legal requirement under State law and will protect growers using the chemical and the consumers of the treated produce.”  The same paragraphs describe the need for spray residues to be below the Maximum Residue Limits (MRLs) on food.  The information derived from residue trials and consumption data can “then be assessed against the Acceptable Daily Intake (ADI) established from the toxicology evaluation of the chemical…”
a.  Limits to the science of toxicology
This document makes no allowance for the limits to the science of toxicology.  For further elaboration on this particular problem see:  http://www.geocities.com/rosserbj/toxicology_limits.html
b.  General lack of toxicity data
Nor the general lack of data for many chemicals now in use:
“For about 75% of the 3,000 or so chemicals in large-scale use, the “minimal” toxicity data required by the OECD for a preliminary assessment of health hazards to humans is not publicly available (NRC, 1984; EDF, 1997). S i m i l a r l y, little is known about eco-toxicity. “It is difficult to even broadly classify chemicals as “dangerous”, under labelling requirements, for example, without minimal toxicity data (Temanord, 1997).”
Source: http://www.chemicalspolicy.org/downloads/Low%20Doses.pdf
c.  MRLs in Australia are set much higher than elsewhere:
Because our level of contamination is much higher.
Examples:
•	DDT in beef – 5mg/kg.  5 times that set in the European Economic Community.
•	Many forestry pesticides set at 10 times more than WHO limits.

WHO DEFINES WHAT IS ‘ACCEPTABLE’?

(ixx)  
Obstruction by the Tasmanian Spray Complaints Unit
The Spray Complaints Unit acts as an office to buffer the industry against public outcry.  This office has made it clear to me (at least) that they have no intention of ‘jeopardising the forest industry’ by interfering with industry aerial spray operations.  A façade of ‘duty of care’ is implemented whenever there is any particular pressure to bear on that office.  For instance, they may test your water before and after spraying but this is more likely if the connecting pipe into the rainwater tank has been disconnected before during and after spraying.  On one occasion I was told that community water tanks had been tested when Gunns Ltd aerial sprayed 100 metres from (at least one residence) in Takone in 2002.  The wind direction leads the spray over the rainwater roof catchment and on top of the neighbours at the time.  I was alarmed to find out some months later that these people were not aware of any testing having been done.
2.  "Operating Principles and Proposed Registration Requirements in Relation to Spray Drift Risk"
Public asked to comment without access to spray drift modelling data
On page 4, ‘Introduction’ this document states that one of the four aims for these spray operating principles was to “Create and maintain a consistent and transparent process for making registration decisions in relation to spray drift assessment and risk mitigation.”

How can this process be transparent when the Chief Scientist for the APVMA has repeatedly failed to provide the spray drift modelling data requested by the Brenda Rosser from the Tasmanian Clean Water Network, Dr Alison Bleaney and, probably, many others?
The APVMA assumes responsibility for how registered chemical products may be used
On page 4:  “The Commonwealth, through the Australian Pesticide and Veterinary Medicines Authority (APVMA), assesses all products prior to registration and determines how those products may be used.  .  .”

What has become clear is that pesticides have been allowed to be used for decades now without evidence of ‘duty of care’ both by the APVMA and by most industry operators.

The APVMA go on to say (on page 5) “If the APVMA finds that spray drift associated with a chemical application would be likely to cause such harm, the APVMA cannot allow that product to be used unless a way can be found to prevent that harm from occurring.”

Yet when the APVMA have been informed of dangerous practices it has turned a blind eye for years.  Only in the past three years has there been any effort on the part of this corporate-funded institution to draft guidelines for safer use.
The APVMA increased the proposed release height for aerial spraying from 3 metres to 15 metres
(For the forest industry). Then the APVMA refused to provide any computerised drift modelling data for spraying at such heights when requested.  What little modelling has been incorporated into these two documents shows an alarming level of pesticide drift under ‘ideal’ conditions and/or with many parameters (such as humidity, topography etc) undefined.

Spraying at such a height cannot be offset by vegetative buffers because the “Tree height should be at least double the release height of the spray.” (Second 2.2.6, page 27 of PISC (SCARM) Report 82).  Spraying on hilly terrain makes vegetative buffers untenable even more so.

These comments are incomplete.  
Answer to Question (b): has the possibility of drift over distances of kilometres beyond target land been dismissed; if so, how and by whom; if not; what safety standards have been instigated or put in place by relevant Government departments and agencies.

(b) No. (That is, the possibility of drift over distances of kilometres has not been dismissed).

 Senator Macdonald goes on to say:  “The Australian Government acknowledges this risk, hence the PISC Report and the APVMA's spray drift management initiative. State/Territory governments acknowledge and manage the risk through legislation governing the control of use of agricultural and veterninary chemicals. These regulations require aerial agricultural spraying businesses and pilots spraying chemicals on a commercial basis to be licensed.

The Tasmanian Department of Primary Industries, Water and Environment would not acknowledge the risk in correspondence sent to me from that department.  Nor, as can be seen above, is it ‘managing the risk’ in any real sense of the term.

In general, aerial spraying businesses are required to be accredited to either the industry-based Aerial Agricultural Association of Australia (AAAA) Operation Spray Safe Standard or an equivalent standard. Meeting this standard ensures that their operational facilities and systems provide the necessary equipment, ground support and safety checks to assist pilots to spray chemicals safely on target and manage the risk of spray drift. Participation in Operation Spray Safe also involves educating clients, including farmers, farm advisers and consultants, so that businesses and pilots are not pressured into applying chemicals under conditions which could result in spray drift.

Macdonald is misleading the public in his last sentence here by implying that spray drift CAN BE avoided. No details have been made available to the public with respect  to the details and regularity of  safety checks.

Pilots are required to have a pilot (chemical rating) license for chemical spraying, based on attaining an AAAA Operation Spray Safe Certificate, or equivalent State/Territory aerial pesticide spraying certification. To be certified, they must have the necessary skills and knowledge to avoid spray drift and minimise the effect of chemical spraying on the environment.

The ‘skills’ Macdonald refers to are not evidenced in practice.

More generic regulations for managing the food safety/human health, occupational health and safety and environmental risks associated with on-farm chemical use apply to farmers undertaking non-commercial crop spraying on their own land. In addition, most, if not all, primary industry sector quality assurance programs include a chemical element which addresses the importance of managing spray drift. Chemical user training and accreditation underpins these arrangements.”

Unfinished document