Tuesday, March 29, 2011

Research casts doubt on Hobo spider risks

Approximately 20 years ago the first reports came out about a new spider associated with necrotic bites in humans (Akre and Myhre. 1991. Melanderia 47:1-30).  This spider, known as the hobo spider, is a European species that is now established in the Pacific Northwestern states of the U.S. and in British Columbia.  Since this time the hobo spider, Tegenaria agrestis, has entered the lexicon of pest control as the third most important venomous spider type in the U.S., behind the brown recluse, Loxosceles reclusa, and the black widows, Latrodectus spp.

New research published in the Journal of Medical Entomology provides evidence that the hobo spider may not be as dangerous as previously believed.  The research by Melissa Gaver-Wainwright and colleagues at Washington State University and University of Pennsylvania at Edinboro, used a sophisticated hemolysis venom assay to determine the ability of the venom to cause tissue destruction like the brown recluse spider.  The research team also looked at the ability of the spider to transfer MRSA, the dangerous bacterial strain for which symptoms have frequently been misdiagnosed as brown recluse spider bites.

Result of the study showed no evidence that the spider causes necrotic bites.  In addition researchers were unable to culture MRSA from the bodies of spiders exposed to the pathogen, nor did they detect MRSA on surfaces that the exposed spiders walked on.

It has been suspected for over 10 years that the hobo spider threat has been exaggerated in the media and even in some industry and scientific publications.   In 2001, for example, Binford (Toxicon 39: 955-968) noted the curious lack of necrotic reports from the native European home of the spider.  They were unable to document any difference in venom between European and American spiders. 

The hobo spider, with its sometime aggressive behavior, made for scary headlines, but in this case at least, truth is duller than fiction.  A free pdf copy of the research is available online.

Bed bug or bedbug

Last week, while reviewing an article in which I was quoted, I commented about the spelling of bed bug.  The article writer was using the condensed (one word) form of the name and I argued that it should be two words. This is consistent, I said, with the way other insect compound names are handled. The editor thanked me for my input and said they would "look into it".

I suspect I know what that means.  The lumpers seem to be winning these days over the splitters, as you will see if you read Jodi Dorsch's editorial in today's PCT magazine.  Jodi tackles the "bedbug" vs. "bed bug" issue and comes out strongly in favor of "bed bug".  She notes the arguments of at least one blogger, Michael Quinion, as the opposing point of view. I agree with Jodi's stance and applaud her efforts. 

The traditional rule that I (and I believe most entomologists) learned for spelling insect names goes like this.  Bed bugs are true “bugs” in the insect order Hemiptera. Typically when an insect name accurately identifies the order to which it belongs, it is spelled as two words (e.g., house fly). But when the insect common name includes an inaccurate descriptor of the insect order, it is spelled as a single word (e.g., dragonfly, which is not a true fly, but it’s own order). Check it out and you'll see this rule is pretty consistent for insect common names (e.g., whitefly, inchworm, cutworm, billbug--none of which are true flies, worms or bugs).

I take some offense to Quinion's statement that "the [one word] spelling has long since become standard for everybody except professional entomologists."  Hey, wait a minute.  Who, besides entomologists wrote about, or even cared about, bed bugs until bed bugs became hip a year or three ago?  And with any kind of professional word, since when does one not look to professionals for guidance with spelling?  If I want to know the proper spelling or pronunciation of a Macpherson strut, I ask a car mechanic. If I'm writing about a cerebrovascular accident (aka stroke) I check my spelling with a medical dictionary. So it would follow that if someone is writing about insects, you would consult with an entomologist. Quinion dismisses any rules (substantiated by the official common names of insects guidelines published by the Entomological Society of America) as a quaint form of "folk entomology".  Excuse me?  I think I'll go have a cerebrovascular accident.

NPDES permit requirements on hold for now

Last August I wrote about the recent court mandate that would require a Clean Water Act permit for activities like community mosquito control and aquatic weed control.  The April 9, 2011 deadline for implementing this new permitting system was rapidly approaching until yesterday, when the Sixth Circuit Court of Appeals granted the U.S. EPA a stay (delay) of the requirements until October 31, 2011.

According to the EPA website, the extension was requested by the agency to allow sufficient time for EPA to engage in Endangered Species Act consultation and complete the development of an electronic database to streamline requests for coverage under the Agency’s general permit. It also allows time for authorized states to finish developing their state permits and for permitting authorities to provide additional outreach to stakeholders on pesticide permit requirements.

Texas has already developed its own state permit, which lays out what Texas communities and businesses have to do to legally apply mosquito adulticides, aquatic herbicides, forestry insecticides and other pesticides to state waters and lands.  This stay will mean that cities, school districts, landowners and businesses in Texas and other states that apply pesticides to more than the minimum area specified in the rules, have more time to develop and submit their permits.

The stay is not related to political opposition to the Clean Water Act's extension into the pesticide world.  Environmental groups have pushed for the CWA to cover pesticide applications for years; however numerous groups (e.g., American Mosquito Control Association, National Cotton Council, Golf Course Superintendent's Association, National Association of State Departments of Agriculture, etc.) have fought hard against the expansion.  Until a court decision in 2009, pesticides were exempt from CWA requirements as long as pesticide labels were followed.  Permits must comply with the National Pollutant Discharge Elimination System (NPDES) of permits.  At least one bill, HR 872 the Reducing Regulatory Burdens Act, would amend the Federal Water Pollution Control Act to exempt pesticides from permit requirements.  That bill was recently voted on favorably (46-8) by the House Transportation and Infrastructure Committee.

Friday, March 11, 2011

Would eliminating Texas' public school IPM requirements affect student health?

New Texas school IPM coordinators get a
lesson in conducting IPM inspections at
East-Central ISD, in San Antonio this week.
On Tuesday the Texas Senate Education Committee held hearings on a bill that relates to school IPM.  Senate Bill 3 (formerly SB 468) is titled "flexibility of the board of trustees of a school district in the management and operation of public schools in the district" deals with several issues relating to efforts to make Texas legislation less costly to school districts.  At the end of the day long hearing (which included testimony from five witnesses who opposed the repeal of school IPM rules and no one specifically in favor), Senator Van de Putte (D- San Antonio) asked Janet Hurley, school IPM program specialist, and I whether in our opinion, repeal of the school IPM legislation would be harmful to childrens' health.

While this is a complex answer to address completely, we both had little choice but to answer yes.  Let me explain why.

Texas' requirement for schools to follow IPM principles and to encourage the use of less toxic pesticides has changed the way pest control is done.  We know, for example, that indoor school environments receive fewer pesticide spray applications today, 16 years after implementation of the IPM law.  Pesticide sprays inevitably deposit residues in places where they can be in contact with children.  One could argue that there is little evidence that proper spray applications pose any significant threat to children's health; but the facts remain that children are more likely to be exposed to potentially harmful spray deposits when they are used more frequently. Most of us would agree that keeping pesticides away from kids is a good thing. This is one of the reasons that the U.S. EPA has pushed schools to consider using IPM for almost 20 years.

A second reason for linking IPM to student health is that repeated research shows that IPM is the most effective way to manage pests.  This has been shown for cockroach control in schools, bed bug control in public housing, and numerous other sites

Why is pest control so important? Consider rodents.  Mice and rats spread human pathogens via feces and urine, invisible deposits of which can be found on food preparation surfaces, floors and desks of infested schools.  This is the situation we saw recently in a south Texas school district that obviously did not have a strong IPM program. I can tell you from personal observation that cockroaches are present in many Texas schools (even with IPM, we're not perfect).  Cockroaches are implicated not only in transmission of disease organisms like Salmonella, but also in allergen production. In some areas, cockroach allergies are just as frequent in human populations at house dust mite, cat, and pollen allergies.  These allergens are frequently encountered in school dust samples (Eggleston PA, Arruda LK. 2001. Ecology and elimination of cockroaches and allergens in the home. J Allergy Clin Immunol 107:S422-S429).  Similarly, house flies, fire ants, bats and other pests are among pests targeted effectively by IPM. Failure to control pests in schools is a failure to provide a safe learning environment for our children. 

If you are willing to accept these claims on the part of IPM, the key remaining question is whether IPM practice is likely to decline in the absence of a state requirement.  If the past history of pest control in Texas is any guide, the answer is not highly encouraging. Prior to 1995, when school IPM legislation went into effect, there were a few schools with good IPM programs, but most districts relied on scheduled spray visits.  One study showed that average satisfaction with pest control programs at that time was low (Damon Shodrock MS thesis, 1994).  According to our research, Texas school districts today are 75% more likely to be satisfied with their pest control program compared to 1993, before the law went into effect. We also found that 75% of school IPM coordinators believe that the Texas IPM requirements have resulted in more effective pest management in their districts.

I don't believe the change we've seen in Texas is completely the result of the pest control industry getting better over time.  Although there are few statewide surveys, and evidence is anecdotal at best, I think it's safe to say that non-regulated states have not made as much progress in the past 20 years as Texas. Colleagues from other states jealously note that it is difficult to raise interest in IPM among school administrators who are not required by some mandate to follow IPM standards.  And if you ask any maintenance professionals familiar with school IPM programs, having the support of school administration is key to IPM success in schools.

We were very appreciative of the opportunity to share these statistics with the Education Committee this week and hope that the Education committee and our legislature will make the decision best for the school children of Texas. Also, if you haven't seen it, a Texas Tribune article reported this week on the issue with voices both for and against the legislation. 

Wednesday, March 2, 2011

The end of School IPM in Texas?

In case you haven't heard, a bill submitted to the Texas Senate earlier this month includes a provision that would eliminate all requirements for schools to follow IPM in our state.  Section 13 paragraph (2) of Senate Bill 468, introduced by Senator Florence Shapiro (R) of Plano, Texas, would repeal Section 1951.212 of the Occupations Code, the section of state law entitled "Integrated Pest Management Programs for School Districts".  The presumed intent of the bill is to reduce costs to Texas school districts in this time of very tight budgets.

In response to a number of inquiries we have had from schools and pest management professionals, I and colleagues have put together some facts concerning school IPM in Texas. We are not advocating for or against the provision of this bill that affects school IPM programs, though most readers of this blog will recognize my belief that the school IPM requirements have played an important role in moving our state's public schools toward a better form of pest control.

When discussing the bill with others, you may find the following information helpful in formulating talking points.  If you need more information, go to the school IPM website, http://schoolipm.tamu.edu. Detailed information about the Texas School IPM model can be found by clicking on the “More Information” button on the right hand side of the page. For specific information about successful IPM programs click on the “Awards and Recognition” button, also on the right hand side of the home page.

Economic Impacts of School IPM Laws
  • There is no evidence that the school IPM law and its associated regulations cost school districts significantly more that what they would normally spend on adequate pest control. In a 2005 Texas AgriLife Extension survey of over 500 IPM Coordinators, 53% felt that the IPM requirements had actually reduced long-term costs of pest management. Fifteen percent believed there was no change in cost to the district. Only 18% of districts said that they felt the school IPM regulations had increased the long-term costs of pest control to their district.
  • Increased costs in labor and training for IPM programs appear to be more than offset by long-term reductions in pest complaints, reduced costs of chemicals, and reduced costs for transportation (responding to pest complaints), etc.
  • Additional school district savings, associated with other IPM programs and likely to be true for Texas schools as well, include reduced liability for pest and pesticide complaints, and healthier work environments resulting in reduced student absences and teacher sick days.
  • There is evidence that many schools are finding substantial cost savings with the switch to IPM. Keller ISD, for example, reduced its costs for contractual pest control from $94,000 to $18,000 between 2008 and 2010, due to better management and bringing some services in-house. 
  • A 2005 study conducted in nine North Carolina elementary schools compared conventional pest control to IPM for German cockroach control. Conventional pest control cost $16.92 per service at the beginning of the study and decreased to a stable $7.50 in the final months; compared to IPM service which intially cost $12.63 per service and declined to $6.20 per service (Williams, Linker, Waldvogel, Leidy, & Schal 2005).
Health and Safety Impacts Associated with IPM
  • According to the Centers for Disease Control and Prevention, asthma is a leading cause of school absence in the U.S. – more than 12 million asthma-related absences per year. Not only is IPM implementation more effective at controlling pests that conventional pest management practices but it can also lead to long-term health benefits, such as reduced exposure to rodent and cockroach allergens, important asthma triggers. For this reason, the U.S. EPA considers IPM to be an important component of its Tools for Schools program advocating for better indoor air quality for schools. 
  • The IPM law has resulted in a shift from more- to less-toxic pesticide use in Texas schools. A 1994 Texas A&M University study showed that the two most consistently used insecticides for indoor and outdoor pests in schools at the time were diazinon and Dursban, two broad-spectrum, residual insecticides that were associated with numerous public complaints. In the 2005 Texas AgriLife Extension Service statewide survey conducted ten years after enactment of the school IPM law, insect baits, followed by insect growth regulators and low-toxicity inorganic insecticides such as boric acid (all preferred products under state regulations) were the most commonly used products. This significant shift away from conventional insecticides has not been seen in school districts from other states.
  • The school IPM law requires good record-keeping from all school districts. This has resulted in better accountability and provides a way to track improvements in pesticide stewardship not commonly seen in schools in other states.
  • In a Maryland study, the Montgomery County Public School System reduced pesticide applications from  5,000 to 600 per year within three years of implementing IPM. Similar reductions have been reported in Texas since implementation of school IPM regulations.
Quality of Pest Control
  • Texas schools have indicated greater satisfaction with their pest control programs, both in-house and contracted, since implementation of the school IPM law. According to the 2005 Texas AgriLife Extension Service study, schools were 75% more likely to be satisfied with their pest control program compared to 1993, before the law went into effect. In addition, the study found that 75% of school IPM coordinators believe that the state IPM requirements have resulted in more effective pest management in their districts.
  • Similar conclusions were found in a 2001 survey of 292 school districts by the then Structural Pest Control Board. In this survey, a substantial majority of schools felt that IPM had resulted in pest control equal to or better than pest control services before the IPM requirements went into effect.
  • Research consistently shows that whenever IPM is implemented in the urban environment it tends to result in better pest control, generally with the use of less hazardous pesticides and less contaminating application methods. There is now nearly universal agreement among regulatory officials, academics, facilities managers, architects and pest management professionals that IPM represents the best available management approach for dealing with pests. 
Other considerations
  • Texas’ law and regulations strike a balance between encouraging use of less hazardous products and methods, and allowing schools the freedom to do what they need to manage pests. Under current rules, Texas schools can use any pesticide they deem necessary.
  • Many school IPM coordinators report receiving greater support for their programs from district administrators because of this law. 
  • Some school district superintendents may be under the mistaken impression that repeal of the school IPM law will save the district money for the training and licensing of school district employees to apply pesticides. However, eliminating Section 1951.212 will not eliminate the need for use of licensed applicators to apply pesticides in schools. For safety purposes all pesticide applications made to restaurants or other food processing establishments, apartments, day-care centers, hospitals, hotels, warehouses, government buildings and schools must be made by licensed individuals (Occupations Code Section 1951.051).
  • Requiring school IPM coordinators to be trained has resulted in schools being better-educated consumers of pest control services. Many districts demand better service, switching to higher quality service providers or bring pest control services in-house at reduced expense. Nationally the trend is for states to require more, not less, training for school pest management personnel.
      To learn more about what you can do about this bill, contact your local professional association.  The Texas Pest Control Association, Texas Association of School Boards, or the Texas IPM Affiliates for Public Schools are each developing position statements on SB 468.  This is a vitally important issue that needs the attention of anyone involved in school health and IPM-related professions today. 

      Tuesday, March 1, 2011

      Car Talk radio show tackles wildlife topic

      Kieran Lindsey, former Texas A&M University wildlife major,
      and now Virginia Tech professor, tackles the subject of
      wildlife and automobile maintenance.

      Any of you who find yourself out driving around on a Saturday morning, and have happened to tune into an National Public Radio station, have probably heard the show Car Talk. Who would have guessed that two goofy brothers answering car maintenance questions on the radio would have been successful? I wouldn't. Yet they've become an enormous hit with a syndicated newspaper column and with NPR listeners with cars over a certain age.

      The Car Talk brothers usually make me laugh. So I was pleasantly surprised a few months ago when I got a call from someone purportedly working for the show, and who needed some advice about pest problems in cars. It turns out that my caller was Dr. Kieran Lindsey, a Texas A&M grad who now works at Virginia Tech and who is moonlighting her wildlife biology skills and knowledge as the "wildlife expert" for Car Talk. An article about Kieran and her new gig just appeared in AgriLife Today.

      I'm proud to report that a couple of the issues we discussed are now part of Kieran's Car Talk webpage called Wildlife and Your Car. So for all the times you wake up in the middle of the night in a panic, worrying about spiders or bed bugs in your car, you now have a place to go online. I know I'll sleep easier knowing that Car Talk has all the answers about what to do should be car is invaded by snakes, rats, goats and cats. Oh, and don't forget the perennial worry about what will happen to your dog in the front seat should your airbag deploy.

      Given the current state of the Texas budget and the economy, Dr. Lindsey gives me great hope. If a wildlife biologist can get a gig advising people how to keep wildlife out of their cars, perhaps there's a place for an unemployed Ph.D. entomologist in the new economy.