Monday, May 31, 2010

Ants star in new novel by E. O. Wilson

Last month I was catching up on some old "All Things Considered" podcasts, and caught an April 2nd interview with renowned entomologist E. O. Wilson of Harvard University (yes there are a few "renowned" entomologists).  In case you are not familiar with Dr. Wilson, he is one of those rare brilliant scientists who can do science well and communicate very well to an audience far beyond the narrow world of insect-ologists.

Wilson could have laid down his collecting forceps and put aside his microscope in comfortable retirement years ago, and felt pretty darn good about his accomplishments.  He was one of the first discoverers of the red imported fire ant, and is author of more than 20 books, including his Pulitzer Prize-winning book, The Ants.  Instead he has continued with his writings, most of which these days have a conservation theme.

Describing himself Wilson says, "Every kid has a bug phase. I just never grew out of mine."  And I for one am glad he hasn't. I had the chance to meet Dr. Wilson several years ago when he gave a lecture at Texas Tech University.  My one claim to fame (if fame includes having an intimate association with a famous person) is that my early years, and possibly the seeds of my interest in biology, were spent in the same small Alabama town as Wilson. Wilson writes about his early years, including time in Brewton, AL, in his memoir, Naturalist.

Anyway, Wilson has recently published his first work of fiction, called Ant Hill: A Novel. In it, ants play a major character part, with some 70 pages devoted to life inside a fictional ant colony.  When asked why he decided to jump into writing fiction, Wilson noted that "whereas people respect non-fiction, they read novels."

Quoting the Publishers' Weekly review,
Wilson (The Ants) channels Huck Finn in his creative coming-of-age debut novel. Split into three parallel worlds—ants, humans, and the biosphere—the story follows young Raff Cody, who escapes the humid summers in Clayville, Ala., by exploring the remote Nokobee wilderness with his cousin, Junior. In one adventure, sneaking onto the property of a reputed multiple murderer to peek at his rumored 1,000-pound pet alligator, 15-year-old Raff faces down the barrel of a rifle. Raff's aversion to game hunting, ant fascination, Boy Scout achievements, and Harvard education all support his core need to remain a naturalist explorer. A remarkable center section meticulously details the life and death of an ant colony. Nearing 30, Raff's desire to preserve the Nokobee reserve from greedy real estate developers galvanizes an effort to protect the sacred land and a surprise violent ending brings everything full circle. Lush with organic details, Wilson's keen eye for the natural world and his acumen for environmental science is on brilliant display in this multifaceted story about human life and its connection to nature.
Every PMP with an interest in ants owes it to him- or herself to check out some of Wilson's writings.  I haven't yet had the time to sit down with Wilson's novel, but it is on my summer reading list.  To hear the interview with E.O. Wilson, click here. To see more reviews, check out the publisher's site.


Friday, May 21, 2010

Mosquito repellent help

Pest management professionals are exposed to all sorts of health risks, including many of the same pests that afflict their customers. Mosquitoes and ticks are among the worst offenders.  Even if you're not in one of the parts of the state where you risk being eaten alive, we all can potentially be affected by West Nile virus and other mosquito- and tick-borne diseases.

A good mosquito repellent is an essential tool for the PMP. Mosquito repellents are without question one of the marvels of technology. Gone are the days of slathering smelly bear grease on your body to ward off the hungry hoardes. Using modern technology, a quick spray or small dab of cream and you can be protected effectively from the bites of mosquitoes, ticks and biting flies for hours.

It's both a blessing and a curse that there are literally hundreds of repellent products on the market. Choosing the best repellent can be confusing. For many years the Centers for Disease Control (CDC) and most entomologists recommended DEET as the most reliable repellent for most pests. I still recommend DEET for most professionals heading out for a day's work, because one application of the right product can provide day-long protection.  But some of us don't care for the smell of many DEET formulations, and others report sensitivity to DEET.  Fortunately, in the past few years researchers have found acceptable alternatives.  Many of these products provide equal protection, although DEET appears to still be tops for length of protection.

The U.S. Environmental Protection Agency (EPA) and the National Pesticide Information Center both recently posted a handy online tool to help you choose a repellent. The core of the calculator is a database that cross-references registered repellents against their expected hourly protection times against ticks and mosquitoes. Simply enter the pest you are concerned about, how long you need protection for, and (if you have one in mind) the active ingredient you are interested in. It then produces a download-able list of commercial repellents that meet your needs.

The calculator is relatively simple and, unfortunately, does not cover biting flies other than mosquitoes. I was also a little disappointed that it doesn’t give a reliability rating or provide references to the research on which the data is based (OK, I’m a skeptical scientist…you may not feel the need for this feature). What you will find if you use the calculator is that there are a number of acceptable alternatives to DEET that you may not be aware of–especially if you don’t need 10 hours of protection.

The EPA calculator can be found at
The NPIC calculator can be found at

Also, for lots more information about mosquitoes and mosquito control, don’t forget the Mosquito Safari website. This site is has lots of information about where to find and how to treat mosquitoes.

So next time you head out for accounts with mosquito activity, don’t forget the repellent. And be thankful for the many alternatives to bear grease.

Tuesday, May 18, 2010

Pesticides and ADHD

In case you haven't seen or heard the story this week about scientific research showing a link between pesticides and attention-deficit/hyperactivity disorder (ADHD) in children, I think it's important enough to pass on.  According to the Time magazine story, researchers at the University of Montreal and Harvard University this week reported in the journal Pediatrics a statistical correlation between ADHD and exposure to organophosphate (OP) pesticides.

Before discussing the results, we should note that there are different ways to study environmental causes of disease.  The most straightforward approach is to take a randomly selected group of subjects from a population you are interested in (say males of a certain age), and subject them to a level of the environmental chemical or condition, say pesticides, or microwaves from cell phones, etc.  You then compare the health of this exposure group over time to a randomly selected group of subjects without the exposure.  This type of controlled experiment is one of the more rigorous ways to test an hypothesis and show a cause-effect relationship.  However, this sort of approach is rarely possible for practical and ethical reasons.  Who wants to volunteer themselves for a study of the possible effects of a toxic chemical on your health?  Fifty dollar stipend anyone?

Another approach would be to look for people who have been naturally exposed (via their lifestyle, or home environment, etc.) to an environmental chemical and compare their health parameters to a group who has not been naturally exposed.  This is a valid research method and has been used many times to study the effects of environmental chemicals on human health.  It's important to realize, however, that this approach measures correlation, which is not the same thing as cause and effect.  If they looked, for example, researchers might find a correlation between heart attacks and watching at least two football games on TV each week.  This would not, however, prove that watching football causes heart attacks.  The actual cause could be something entirely different.  Something co-related to football watching, like lack of exercise and big bowls of greasy nachos!!?  The point is that it is very easy to have a correlation without a cause and effect relationship.

Of course this was the same argument cigarette companies made for many years.  Correlations, if done properly, can provide valuable suggestive evidence, but must always be looked at critically to make sure that all relevant variables have been properly controlled. Typically correlative studies are done as preliminary to a more rigorous study, or as a second choice when more rigorous studies are not possible to conduct.  We cannot afford to dismiss correlations as uninformative.

In the case of this study from the University of Montreal, Maryse Bouchard and a team of colleagues analyzed the levels of chemicals called dialkyl phosphates in the urine of more than 1,100 children ages 8 to 15.  Dialkyl phosphates (DAPs) are metabolic "breakdown" products of OPs. Like nacho crumbs left in the sofa cushion, DAPs are left behind in the blood and the urine after someone has been exposed to OP pesticides. Measuring DAPs in blood and urine is much more sensitive than acetylcholinesterase tests (used by many PMPs in the past to measure OP overexposure), and an accepted way to document previous exposure to OP pesticides in epidemiological studies.  Bouchard's study found that children in the study group with the highest levels of which are breakdown products of OPs had the highest incidence of ADHD.  In other words, there was a correlation between DAPs and ADHD.  To see a free abstract of the study, click here.

The researchers, as all good researchers should, made it clear that this is a correlation which falls short of proof that organophosphate insecticides are a cause, or even a contributing factor to, ADHD.  I am no expert on ADHD, nor on the validity of the chemical analyses or the epidemiological methods used by the authors of this study, but studies like this serve as a cautionary tale for the use of pesticides in urban environments or on food.  The possibility of subtle health effects on humans is always present with the widespread use of synthetic chemicals. But the potential risks always must be weighed against the undoubted benefits of pest control.

Here are a few things to keep in mind should you find yourself in the position of justifying to local media or your customers the use of pesticides as pest control tools.
  • The pesticide class which was the focus of this study is, for the most part, no longer widely used in the pest control industry.  Organophosphates (such as diazinon, malathion, chlorpyrifos, acephate, and safrotin) have been largely supplanted by pyrethroid insecticides and even newer classes of chemistry.  The results of this study apply only to OPs and not to all pesticides.
  • The study did not attempt to prove a cause-effect relationship between OP pesticides and ADHD.  The study, for example, as the authors admit, could not fully rule out that some behavior factor common to ADHD children might cause them to have higher frequency of contact with OP pesticides. 
  • The source(s) of OP exposure was not identified by the study.  Much of the exposures of children to these older pesticides likely come from dietary sources, especially since OP use by the pest control industry was already in decline during the years when the data was collected. 
  • Any pest control company practicing IPM and safe application methods should at best be a minor and occasional source of pesticide exposure to customers.  Risk, or toxicity, of a pesticides is a product of two factors: (1) the toxicity of the pesticide and (2) how much exposure one has to that pesticide.  If labels are being followed, care is being taken to place pesticides only in places where people are unlikely to contact them, and lowest risk pesticides are being used, then the risk of harm to human health should be very small.
The results of this study do not negate the regulatory process that evaluates the safety of pesticides in use by the industry today.  Testing required by the U.S. Environmental Protection Agency for pesticides remains some of the most stringent consumer product testing in the world.  That said, no regulatory system can guarantee safety of any product or practice.  It's often said you can't prove absolute safety, because that's the same thing as trying to prove a negative--it's beyond the scope of experimental science.  We can only hope to guarantee a certain level of safety.  That is why a 100-fold safety factor is built into our current pesticide regulatory system, and why continual review of pesticides goes on between agency and manufacturers.  If a causal relationship is determined to exist between OP insecticides and ADHD, this new data will be taken into account by the EPA, and regulatory changes will undoubtedly be made, as they have for other pesticides.

If I were convinced that we could do IPM effectively without pesticides, I would certainly be a supporter of "no more pesticides".  But not all pesticides are equally risky, and the reality is that pesticides can be useful and even essential tools in our competition with pests. 

Until we find even safer ways to control pests, I will continue to study the use of pesticides, teach and preach pesticide safety, and recommend their use.  And in the meantime, if you really want to protect your health... cut back on the nachos. : )

    Friday, May 7, 2010

    PMPs ride bikes

    Heather and I preparing to ride in the Sam's Club MS 150 bike ride last weekend.  Our team, the Cheesy Riders is sponsored by Pepsico and Frito Lay, whose headquarters is in Plano, TX
    Last week I included a note about riding in the Sam's Club MS 150 bicycle ride, in support of research efforts to fight multiple sclerosis.  Well, I'm happy to report that my wife Heather and I rode and finished the two-day, 159 mile ride across the rolling prairie north of Dallas and Fort Worth.  Thanks to all of you who supported me with donations to the National Multiple Sclerosis Society.  We came away with sore legs and shoulders, good memories, a great sense of accomplishment and a promise to ourselves to avoid our bicycle saddles for a few weeks.  We also made a few new friends, and ran into some old ones.  One of the teams riding last weekend was "Team Termidor", put together by Mike Toce, Regional Sales Manager for BASF, out of Southlake, TX.

    Team Termidor 2010, from left, included Dennis Jenkins, Mike Toce, Mike Cohn, Matt Burns, Fred Webb, Brian Kelley, Bobby Jenkins, Tom Rainer
    It's refreshing to know that you have pest control colleagues that share your quirkiness.  Quirky in the sense they're willing to squeeze into tight shorts, put on funny helmets and pedal like mad for five hours for fun and a worthy cause (I didn't check to see how many of them shaved their legs). I'm sure many of you have similar stories of running into fellow PMPs at races, sporting events, and vacations far from home. If so, feel free to share in the comments section with the rest of us.

    Tuesday, May 4, 2010

    Formosan termite swarming season

    'Tis the season to be on the lookout for Formosan termite swarmers.  Over four seasons of monitoring Formosan termites in the Dallas area suggests that the north Texas swarming season ranges from mid-May to mid-June. Since 1999 my lab has documented Formosan termites from approximately 20 sites in north Texas.  Most of these sites seem to be associated with the transport and use of railroad cross-ties as landscaping timbers.

    I am always glad to receive reports of suspected Formosan termites, but this year I am especially interested.   Our office, in cooperation with Dr. Roger Gold's lab in College Station, is contracting this summer with the Texas Department of Agriculture to map out active Formosan termites sites throughout Texas. To do this, we are returning to sites where we have previously collected this termite and placing out both light traps and ground monitoring stations. We want to do a better job of identifying infested areas, and (we hope) determine whether they have spread.

    We need your help. If you know of any old or new sites (through specimens), would you consider calling us? Collection information we need includes: specific address, owner, owner’s phone and/or email, and dates and circumstances of collection (including whether the termites were collected indoors or outdoors). If you or your technician do find a new site, we would be very interested to know whether railroad crossties are located on or near the property, or whether the infestation can be traced to some other source.

    Formosan termite swarmers (right) are larger and lighter in color than eastern subterranean termites (left). Winged reproductives can be distinguished from drywood termite swarmers by the 2 (instead of 3 or more) thickened veins in the leading edge of the forewings. Formosans fly at night, instead of during the day, like Reticulitermes. If you are in north Texas and see anything remotely like one of these termites, please let us know by calling 972-231-5362 and asking for me or Dr. Charlie Helpert. Any sightings from central, south, or coastal areas of the state should be reported to the Center for Urban and Industrial Entomology in College Station at 979-845-5855.  Any specimens collected should be placed in ethyl or rubbing alcohol as soon as possible.

    As always, your help is greatly appreciated.

    If you don't have a copy of the PCT Field Guide for the Management of Structure-infesting Ants, now's a good time to get one.  The third edition just came out and at $9.95 it's a bargain.  I can't imagine being in pest control and not having a copy of this guide.  Check it out.

    Monday, May 3, 2010

    Objective (mostly) pesticide information from the NPIC

    The National Pesticide Information Center (NPIC) celebrated its 15th year of operating out of Oregon State University last month.  Originally known as the National Pesticide Telecommunications Network (NPTN--from back in the day when telecommunications meant land-line phones) the Center has been partly funded by the U.S. Environmental Protection Agency for more than 30 years.

    There's even a Texas connection to the Center. The pesticide information service began as a place to report spills, misapplications, or unintended pesticide exposures at the Texas Tech University Health Sciences Center in San Benito. Later, as the center began to receive calls from across the U.S., the Center evolved into a place for the public to get general information on pesticides.  It resided at Texas Tech University's Health Sciences Center in Lubbock, Texas between 1986 and 1995, and, after a competitive process NPTN moved to Oregon State University in April 1995.

    Renamed the NPIC in 2001, the primary mission of the National Pesticide Information Center has not changed.  It's mission is to serve as a source of objective, science-based information on a wide variety of pesticide-related subjects, including:
    • recognition and management of pesticide poisonings
    • health and environmental effects of pesticides
    • toxicology
    • environmental chemistry
    • pesticide products
    In addition, NPIC provides referrals for:
    • safety practices
    • clean-up and disposal
    • emergency treatment
    • investigation of pesticide incidents
    • laboratory analysis
    It's interesting to reflect on some of the changes since 1995.  In its first year of operation, the Center responded to 17,775 phone calls. Last year 2008-2009, the Center responded to 26,449 telephone calls (Toll-free at 800-858-7378) and registered 2.4 million hits on their website:  In 1995, 1852 of the calls received (10% of the total) concerned chlorpyrifos (Dursban--remember that product?).  Today, moth balls, boric acid and pyrethrins are the subjects of some of the most frequent calls, emails, or website visits.  Over 40% of the calls related to pesticides in general, and 39% of the inquiries related to specific products.  The annual reports are very detailed and, I think, surprisingly interesting for anyone with an interest in what consumers are thinking about pesticides.

    For the most part, I believe the NPIC does a pretty good job of meeting its objectives.  From my perspective there does seem to be a slight anti-pesticide emphasis, but this is what one should expect from a Center whose directors are toxicologists, and who's focus is on the potential health effects of pesticides rather than on the benefits pesticides provide in pest control. In a way, I think this can work in your favor as a PMP.

    Consider recommending the NPIC as a resource for your wariest customers--you know, those good folks who believe all pesticides are "radioactive".  The Center doesn't sugar-coat toxicology issues.  The materials I have read seem pretty well balanced and at least attempt to balance risks and benefits of pesticides and specific active ingredients.  Your customers can learn about the relationship between dose and response, and will get relatively objective assessments of the relative toxicities of different active ingredients. 

    Anyone who is skilled in the business of pest control today should not fear an educated customer.  The only thing we "might should" get a little nervous about (to use a good southern expression), is a customer who knows more about a subject than we do.  So check out the NPIC website and look up some stuff yourself.  We can all will find information there that we need to know.