David G. Patriquin
e-mail: patriqui@dal.ca

January 25, 2005.

To: Mayor Peter Kelly and HRM Councilors
cc: Stephen King, (Environmental Management Services, HRM)
Clean Nova Scotia, Ecology Action Centre, Landscape Nova Scotia, RATE

Dear Mayor Kelly and Councilors,

I am writing to urge that council take actions to reduce the number of permits for pesticides issued under the Pesticide By-law to zero or very close to zero in 2005 and, in particular, to initiate certain actions well before spring.

Overall, the Pesticide By-law has been highly successful, especially in regard to herbicides.¹ However the 2004 Pesticide By-law Program Overview, tabled January 11, identifies some significant outstanding issues, most of which relate in one way or another to pesticide permits issued for control of chinch bug. Several thousand pesticide permits were issued in each of 2003 and 2004, more than 99% of them for control of chinch bug in lawns.² The pesticides involved - diazinon and Sevin (carbaryl) - are ones which the PMRA (Health Canada's Pest Management Regulatory Agency) recognizes as posing significant health risks, especially for children. Thus we need to move as quickly as possible to achieve zero or near zero use of these pesticides, or of other 'hard' pesticides that might replace them, in 2005.

I suggest that three steps, outlined herein, need to be taken well before spring. These are (i) provision of educational materials to residents that received permits in 2003/2004 and encouraging lawncare companies to begin marketing relevant services and materials early in the season; (ii) ensuring that insecticidal soap, a 'soft' pesticide³, is available for control of chinch bugs in 2005; (iii) removing pyrethrum products from Administrative Order No. 23 (the Pesticide By-law Exclusion List). As outlined in the 2004 Program Overview, some actions have already been taken in regard to (i) and (ii) and I am simply supporting the argument for further action in those areas in 2005. The pyrethrum matter was not identified in the 2004 Program Overview but could become a contentious issue if pyrethrum products are registered for use against chinch bug or if these materials are used extensively for other pests; you may already be aware of some concern in the community about this category of pesticides.

Educational Materials
First, I urge HRM to begin its educational activities in relation to the Pesticide By-law well before spring is upon us. The experiences of 2003 and 2004 indicate that chinch bug will be a chronic problem in HRM lawns until appropriate cultural controls are more widely practiced and new lawn construction standards are implemented.⁴ Spring is the optimum time to implement certain of the cultural controls, e.g. aeration, overseeding with clover, application of compost. I suggest that information about cultural practices to control chinch bugs be distributed in March or earlier to property owners who received pesticide permits last year. Given fair advance notice, repeat permits might then not be granted at all in 2005 or not granted unless certain cultural measures have been implemented and attempts to control any outbreaks by monitoring and vacuuming or application of soap (as permitted) have been made. For example, required cultural controls might be two or more chosen from a set of controls such as aeration/dethatching, topdressing with a compost+soil mixture, overseeding with clover, mulch mowing at 2.5 inches (6 cm) or higher, cessation of fertilizer applications from June 5 to Aug 15, regular watering of drought-prone areas. Instructions could be given on how to monitor lawns for chinch bug and how treat any areas showing early signs of damage by chinch bug.

It is important that developers, topsoil manufacturers and lawncare companies are brought into this process. Thin and/or poor quality topsoils in newer developments are a major factor in the high incidence of chinch bug problems in those areas.⁵ The 2004 Program Overview cites opportunities for a Topsoil Availability/Sustainability Partnership and I have been told that HRM staff are organizing workshop on the topsoil issue in March.

CORRECTION Some of the numbers cited in the original letter at left are incorrect: the percentage of applications that came from companies in 2003 was 82% (3180 applications), NOT 72% as stated. (I made a mistake in adding up numbers for different companies cited in the 2003 Program Overview Report .)* It is still true that the number of applications from companies increased in both relative and absolute terms between 2003 and 2004, however there was a small decline (7%) in the total number of applications received from companies that were actually approved rather than the small increase (4%) implied by the numbers at left. *Thanks to Greg MacAskill of the Ecology Action Centre for pointing this out, and my apologies for the mistake. - dp 28 May, 2005.

I suggest that it would likewise be appropriate to develop a partnership with lawncare companies to promote cultural controls of chinch bug. In 2004, at least some lawncare companies seemed to have intensified their marketing of pesticide treatments even though weather conditions were much less conducive to chinch bug than in 2003. While there was a decline in the total number of applications for pesticide permits between 2003 (3863 applications) and 2004 (3365 applications), the decline was associated with a decline in applications from individuals (38% of total applications in 2003, 2% in 2004) rather than in those from lawncare companies. The applications for Pesticide Permits from companies actually increased in both relative terms (72% of total applications in 2003 and 98% in 2004) and absolute terms (2791 applications were submitted by companies in 2003 and 3297 in 2004; approximately 2531 applications from companies were approved in 2003 and 2638 in 2004).6 Of course, not all lawncare companies were involved and some companies do emphasize cultural controls over pesticides. Encouraging the lawncare industry at large to begin marketing services and materials related to cultural control of chinch bug early in the 2005 season would be a positive way to raise awareness of these issues, and to involve the industry in the public education process.

Insecticidal Soap
Second, I suggest that we need to press Health Canada at the highest levels to expedite a product extension that would allow insecticidal soap to be used for control of chinch bug. Currently, the only pesticides that are permitted by the PMRA for control of chinch bug are diazinon (an organophosphate) and Sevin (carbaryl of Bhopal fame, a carbamate pesticide). Both are cholinesterase inhibitors that are recognized as unsafe in the domestic environment by pesticide regulating agencies in Canada and the U.S, particularly for children, and have been targeted for removal from the domestic market. In the U.S., several alternative, much more benign materials for humans and the environment, or 'soft' pesticides, are also registered for control of chinch bug, such as insecticidal soap. However, this is not the case in Canada. The befuddling result is that the only pesticides that can legally be used against chinch bug in Canada are those which the PMRA itself considers unsafe in the domestic environment, while we cannot use insecticidal soap in our own backyards. (Insecticidal soap is a refined natural soap which is no more hazardous than natural soap.) ⁴

This situation is very difficult to understand, especially as the PMRA is a branch of Health Canada, but there it is. We have an urgent need for access to insecticidal soap to control chinch bug. Insecticidal soap is widely available in Canada for use against a variety of insects (but not chinch bug); it's on the HRM Administrative Order No. 23 list, and it is effective against chinch bug and is registered for that use in the U.S. In Canada we are not permitted to use insecticidal soap to control chinch bug simply because it is not registered for this specific use in Canada. The PMRA apparently does not solicit registration of particular materials, but rather responds to requests from manufacturers. It's possible that manufacturers of insecticidal soap have put forward applications for a product extension that would allow use of insecticidal soap against chinch bug and that this matter is currently being considered.⁷ However, it is also possible that such applications have been or will be turned down. We are not privy to this information because the PMRA does not provide any information unless and until an application is actually approved. So we cannot assume that applications for product extensions are currently being considered, or even if they are, that a product might be approved in time for us to have access to insecticidal soap in 2005. The 2004 Program Overview cites several examples of slow action by the PMRA on issues that are of importance in relation to the pesticide By-law.

Therefore I suggest that this matter be taken directly to Anne McLellan, the Federal Minister of Health, e.g., through a letter from the Mayor and council appealing to the Minister to expedite the registration of Insecticidal Soap for use against chinch bug. I think that the Minister would be responsive to the soap issue: there have been well publicized discussions of the hazards of domestic pesticide use by citizens, physicians and in the House of Commons; the current situation (in which we are entitled to use only materials already targeted for removal because of recognized health risks) is completely non-sensible and inconsistent with the mandate of Health Canada; and HRM has a well recognized leadership role in development of precautionary approaches to urban pesticide use. Insecticidal soap would provide a much needed tool for lawncare companies and individuals, and greatly reduce if not eliminate the need to issue permits for use of the hard pesticides.⁸

Pyrethrum Products
One potentially dark cloud in this scenario is the current inclusion of pyrethrum (or pyrethrin)⁹ on Administrative Order 23 (the Pesticide By-law Exclusion List, or list of permissible pesticides) combined with the distinct possibility that the PMRA will approve use of pyrethrum products for control of chinch bug.¹⁰ This could result in large scale use of these pesticides on lawns by lawncare companies and individuals without restriction. Pyrethrum (or pyrethrin), like rotenone and nicotine, is a natural product but nonetheless is a 'hard' pesticide. Pyrethrum and pyrethrins are strong allergens, pose other significant health risks to humans including possible carcinogenic effects, and have broad spectrum action (killing beneficial insects and non-target organisms). Pyrethroids, which are synthetic analogues of the natural products, share those qualities and are further problematical because of longer persistence in the environment, higher toxicity and a broader range of suspected adversities, including estrogenic activity and neurodevelopmental effects. Infants are particularly sensitive to pyrethrum products. There are additional risks associated with synergists commonly added to the products, and according to the formulations, with other unlisted ingredients which are not required to be identified. A recent, comprehensive US Public Health Service document on pyrethrum products¹¹ makes it clear that considerable caution in their use is appropriate and that use as horticultural pesticides, as on lawns, must be subject to the usual sorts of restrictions placed on such pesticides; in HRM, that means allowing use only with a permit. Thus pyrethrum (or pyrethrin) should be removed from the Administrative Order No. 23 list. ¹²

I am very grateful for your consideration of these matters. The leadership of HRM elected officials and staff in this area is widely appreciated within HRM and beyond. As well as protecting our own citizens, the Pesticide By-law and what we do with it as new challenges arise has a strong influence on the many other communities following our lead. Commercial enterprises also benefit by being on the forefront of new approaches to sustainable management of cities.

Respectfully,

David G. Patriquin

David G. Patriquin

(Professor of Biology)

Enclosure: Notes 1-12

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NOTES

Note 1 The HRM Pesticide By-law Program Overviews indicate there have been no applications for use of herbicides under the notwithstanding clause.

Note 2 Under the notwithstanding clause "a pesticide application may be carried out to control or destroy plants or insects if such plants or insects constitute a danger for human beings or to control or destroy insects which have infested a property, if such pesticide application is specifically permitted by the Inspector for that purpose and the pesticide application is carried out subject to such terms and conditions as shall be prescribed by the Inspector." In 2003, there were 3,863 applications for permits, 72% were from companies, 91% were approved, over 99% of the applications were for chinch bug; in 2004, there were 3365 applications, 98% were submitted by companies, over 99% were for chinch bug, 80% were approved (figures from the 2003 and 2004 Program Overviews).

Note 3 Legally, any substance used to control a pest through chemical or biological action is defined as a 'pesticide'. The terms 'soft' and 'hard' pesticides are coming into use to distinguish pesticides such as soaps and oils from the traditional types of pesticides. Soft pesticides are mostly natural products that decompose quickly and completely, have little or no ill effects on humans and either do not affect natural enemies of pests or allow quick reinvasion of treated areas by natural enemies. Many of them, e.g., soap and certain essential oils, have an ancient history of use by humans as pesticides or pest repellents or for other purposes, but have not been exploited in the modern context until recently. These soft pesticides are especially appropriate in modern, integrated systems of pest control such as 'Biointensive IPM' (www.attra.org/attra-pub/ipm.html). Hard pesticides are the traditional, mostly synthetic pesticides but also include certain botanical pesticides such as nicotine; they are generally broad spectrum in their action, decompose slowly and/or incompletely and pose significant health risks.

Note 4 Please see the website Control of Chinch Bug Without Pesticides (www.versicolor.ca/lawns) for factual information and references related to insecticidal soap, pyrethrum products, permitted materials lists, regulatory issues and cultural practices for control of chinch bug.

Note 5 From the 2003 Program Overview: "Regarding chinch bug, in many cases, applications came from locations with poor quality and/or insufficient soil, or other poor growing conditions." From the 2004 Program Overview: "This year Regional Council raised the issue of insufficient and/ or poor quality topsoil at new home construction sites resulting in pest and maintenance problems for the homeowners shortly thereafter. Regional Council therefore asked staff to look at ways where HRM could influence better topsoil practices at new home construction sites."

Note 6 Statistics are taken from the 2003 and 2004 Program Overviews, or were calculated from those statistics, e.g., the total number of permits given to companies were estimated as (total number of applications for permits X the percent of applications from companies X the percent approval overall).

Note 7 See the 2004 Overview, page 14: "EAC has encouraged two manufacturers in Canada to register their products".

Note 8 An important benefit of insecticidal soap is that it would eliminate all of the exposure to regular (hard) pesticides which occurs due to overuse of pesticides. That occurs even under an IPM type process in which pesticides are used only when there is evidence from monitoring that a particular pest is present and could cause damage (as in the Pesticide Permit process). Any system of predicting eventual damage from presence of pests or early signs of damage is less than perfect: there will always be situations in which serious damage would not develop even if pesticides were not applied, e.g., because of misdiagnoses, or because the subsequent weather conditions are not conducive to the pest, or because the real cause of damage was a factor other than the target pest even though it was present. It is a catch-22 situation: if pesticides are NOT applied, there is a risk that serious damage will occur; if pesticides ARE applied, serious damage will (hopefully) not occur, but pesticides may not have been necessary. It seems quite likely that the latter was frequently the case in 2004 when weather conditions overall were not favourable for chinch bug proliferation and we did not see the massive damage seen in 2003. High initial populations and some initial damage in 2004 - which were used as criteria for issuing permits - could have been associated with carryover (overwintering) of the large chinch bug populations that accrued in 2003 rather than conditions in 2004. Also, in general, the pesticide applicators spray whole lawns, not just the affected areas, and as noted in the text, lawncare companies seemed to have conducted more intensive marketing of pesticide treatments in 2004 compared to 2003. If soap (or vacuuming), rather than hard pesticides are used, there may still be overuse of treatments, but these treatments do not entail exposure of operators and residents to hard pesticides. In addition, combined with monitoring, soap (or vacuuming) will likely control most if not all of the real chinch bug threats.

Note 9 The term 'pyrethrin product' is used here to refer to any product containing pyrethrum and/or concentrated pyrethrins and//or pyrethroids. Administrative Order No. 23 refers to 'Pyrethrum (or pyrethrin)'. The term 'pyrethrum' is generally used to refer only to powders made from the pyrethrum daisy without refinement, however it is sometimes used or as a general name covering both natural compounds and their synthetic analogues. 'Pyrethrin' refers to any or all of the different forms of the biochemical 'pyrethrin' that are responsible for the pesticidal activity of the natural materials; often these are concentrated by extraction for use in pesticides. 'Pyrethroid' refers to synthetic compounds designed to resemble the pyrethrins. Under the HRM By-law, only pyrethrum and pyrethrins are permitted, and not pyrethroids and not synergists or undeclared ingredients added to many pyrethrum products. In practice however, this level of discrimination of products is not practiced at the retail level and would be difficult to apply without expert review. For this reason, as well as because of their broad spectrum activity and significant health risks, even the natural products are restricted under OMRI (see note 12 below).

Note 10 The reason for suspecting that the PMRA may approve pyrethrum products for use against chinch is two-fold. (i) In principle (and hopefully in practice ) diazinon will NOT be available in 2005, leaving only Sevin (carbaryl) as an approved pesticide for use against chinch bug. The PMRA has declared that carbaryl needs to be removed from the domestic market, so they will be looking for other products to be registered. Pyrethrum products are already approved for domestic use and in the U.S. are approved for use against chinch bug, which would simplify their registration for use against chinch bug in Canada. (ii) Officially, I believe, the PMRA does not solicit companies or users to seek registration of particular products. However, in 2004, I received a bonafide report that in response to an inquiry about getting insecticidal soap registered, the PMRA suggested the best option would be to seek registration of a soap product containing pyrethrins.

Note 11 See: "Agency for Toxic Substances and Disease Registry (ATSDR). 2003. Toxicological Profile for Pyrethrins and Pyrethroids. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service." (Available at www.atsdr.cdc.gov/toxprofiles/tp155.html). The following is from the Extoxnet Toxicology Network (http://extoxnet.orst.edu/pips/pyrethri.htm):

"Synthetic pyrethroid compounds vary in their toxicity as do the natural pyrethrins. Pyrethrum carries the signal word CAUTION. Inhaling high levels of pyrethrum may bring about asthmatic breathing, sneezing, nasal stuffiness, headache, nausea, incoordination, tremors, convulsions, facial flushing and swelling, and burning and itching sensations (102). The most severe poisonings have been reported in infants, who are not able to efficiently break down pyrethrum."

Note 12 Pyrethrum (or pyrethrin) was apparently included in Administrative Order No. 23 originally because HRM made use of the OMRI Lists of Permitted Materials in deciding what should be included in the Administrative Order No. 23. OMRI is the Organic Materials Review Institute which publishes lists of materials that are acceptable for use in certified organic farming and horticulture. Pyrethrum (or pyrethrin) is listed by OMRI, however, OMRI classifies pyrethrum (or pyrethrin) as a Restricted material, not an Allowed material. The Restricted status means that a farmer or horticulturalist who wishes to use pyrethrum (or pyrethrin) must make a special application to the certifying organization to justify one-time use, and that is granted only under the condition that suitable approved alternatives are not available and that cultural or other measures are taken to reduce the intensity of the pest problem in future. Also, even for this restricted use, OMRI approves only specific products that it verifies are free of synthetic pyrethrins (pyrethroids), synergists such as PBO, any undeclared constituents, and any other materials that are prohibited under OMRI. According to SOUL (Society of Organic Urban Land Care Professionals, based in Victoria, B.C.), "there are currently no pyrethrum products registered in Canada that do not contain synthetic contaminants." Clearly, in the HRM situation, pyrethrum (or pyrethrin) should have similar restrictions, which means it should be useable only with a pesticide permit, i.e. it should not be listed in Administrative Order No. 23.