West Virginia University

Extension Service


January-March 2002

Dr. John F. Baniecki, Extension Specialist in Plant Pathology/Entomology,
Pest Management Program


 

It’s All Natural and Everywhere

ARSENIC 

Like it or not, you will be exposed to arsenic regardless of whether you have CCA-treated wood in your backyard.  Arsenic (chemical symbol As) is one of the 103 naturally occurring elements; it has a natural abundance in rocks and soils.  The soil concentration of As worldwide has been estimated to range from 1-50 mg/kg (milligram As per kilogram soil).  All plants, cultivated or wild, can absorb small amounts of this element.  The extent of arsenic absorption varies among species and the amounts in the fruit often are lower than in the roots and shoots.  From a chemist’s viewpoint, arsenic is related to phosphorus, an essential element for plant growth.  Indeed, arsenic may be taken up by plants because it is absorbed by the same physiological process used for uptake of phosphates.  Thus, every time you eat, you ingest various amounts of arsenic.  Unlike other metals known to be essential nutrients for good health, arsenic’s necessity in the diet is still an open question. 

What You Can DoIf You Are Still Worried About Arsenic from CCA-Treated Wood

- If you’re sawing treated wood, wear a dust mask, wear a shirt and long pants, and wash thoroughly when finished.
  - Do not make playscapes from CCA-treated wood; consider alternatives like cedar or synthetic materials.
- Grow ornamental (as opposed to edible plants near the borders of garden beds outlined in treated wood.
  - Restrict children’s access to areas directly under decks made with treated wood.
- Keep decks in good shape with sealants.
- Never burn treated wood nor use the sawdust in mulch.

 Agrichemical & Environmental News, June 2001 - Dr. Alan Felsot, Environmental Toxicologist, WSU 


Pesticides as “Fertility Drugs” for Mites

 The obvious aim of insecticides and miticides is to kill offending bugs as quickly as possible; formulations and application rates are developed with this aim in mind.  However, as we develop and use pesticides that are more targeted to particular pests (as opposed to the broad-spectrum, “annihilate everything” approach), many non-target insects and mites are exposed to less-than-deadly (“sublethal”) concentrations of chemicals.

 Studies on the sublethal effects of pesticides on insects and mites often show measurable impacts on longevity and reproduction.  Length of bug life can be shortened by exposure to sublethal doses of chemicals, perhaps by subtly interfering with normal body maintenance.  A shorter bug life may mean a shorter period of reproduction and ultimately a population decline.  Some fungicides, while not killing predatory mites, act as sterilants, thus suppressing biological control almost as effectively as predator-toxic insecticides. 


Viagra  for Mites? 

However, not all sublethal effects of pesticides on insects and mites are necessarily detrimental to the species involved or to overall pest manage-ment.  In 1997, Dr. David G. James, Entomologist at Washington State University, showed that an Australian predatory mite important in biological control programs increased egg production by 25-54% when exposed to the sphicide imidacloprid (Provado, Admire).  Predatory mite populations in orchards sprayed with this aphicide were larger than in orchards where this aphicide was not used.  

Agrichemical & Environmental News, July 2001 – Dr. David G. James, Entomologist, WSU 


The Future of Insect Pathogens

 Control of pest insects using chemical pesticides has generated several problems including insecticide resistance; outbreaks of secondary pests normally held in check by natural enemies; safety risks for humans and domestic animals; contamination of ground water; decreased biodiversity; and other environmental concerns.  These problems and sustainability of programs based predominantly on conventional insecti-cides have stimulated increased interest in IPM.

 Sustainable agriculture in the 21st century will rely increasingly on alternative interventions to chemical pesticides for pest management that are environmentally friendly and reduce the amount of human contact with pesticides.  The mandate of the 1996 Food Quality Protection Act (FQPA) strongly influences the development and registra-tion of chemical pesticides today and will continue to do so in the future.

 Certain microbial control agents can help fill the void left by phased-out chemicals, but their further development and implementation will require improvements in the production and formulation of pathogens; better understanding of how they will fit into integrated systems; greater appreciation for their full advantages (e.g., efficacy, safety, selectivity), not simply their comparison with chemical pesticides; and acceptance by growers and the general public.  If future development is driven exclusively by the market, implementation of microbial control agents will be delayed.

 Agrichemical & Environmental News, September  2001 Drs. Lawrence A Lacey, Roger Frutos, Harry K. Kaya, and Patrick VailSeptember 2001


 Checklist for Responsible Pesticide Ownership and Storage

 For those of you, as growers, who store pesticides, it may be well to go over a check list for responsible pesticide ownership and storage.  Due to recent terrorist activities, there is concern for heightened awareness.

- Secure all pesticides; lock storage areas (where fire codes permit).
- Secure all application equipment.
- Choose storage areas not easily vandalized or destroyed.

- Know who has access (keys) to your pesticides.
- Post all storage areas.
- Inspect storage areas on a regular schedule.
- Inventory your stock and records on a regular schedule; have your inventory readily available for authorities.
- Maintain complete and proper Personal Protective Equipment (PPE) items for all employees.
- Make pesticides available to authorized parties only.
- Report any suspicious or inappropriate activity (unusual purchases, illogical behavior) or inquiries immediately.
- Report theft of pesticides or equipment immediately.
- Apprise employees of these concerns; empower them to report suspicious or inappropriate activity.


Heightened Awareness

 Of course, it’s easy to point fingers at others after the fact.  Some of us, after hearing the news reports about the aerial applicator mechanic in Florida who had apparently been visited and queried by individuals with terrorist intent, disparaged the mechanic for not seeing the danger in the situation.  But would we have reacted any differently had we been in his situation?  The time has come to be vigilant, not out of fear, but out of respect for our responsi-bilities.  The e-mail exchange described above is an example of a suspicious activity that any one of us might have brushed off six months ago, yet today we believe that such an inquiry bears investigation.  We hope that anyone in a similar situation would react in the same way. 

 Examples of other suspicious behaviors (adapted from the resources listed at the end of this article) might include someone engaging in any of the following behaviors:

- purchasing large amounts of a highly toxic chemical with cash;
- asking specific questions about toxicity of a chemical;
- being overly curious about a particular detail regarding application equipment (e.g., tank size, spray range);
- loitering near pesticide storage areas without a good reason for being there; or
- presenting strange-looking (possibly altered) license documentation or other credentials.

 Let your instincts, training, and good sense be your guide when it comes to dealing with the public.  And please keep these basic responsibili-ties in mind: 

 - Secure agrichemicals and application equipment.
 - Stay alert.
 - Report suspicious and inappropriate activities to the authorities.

 These points were made clear by Carol Ramsay, Pesticide Education Specialist; Dr. Catherine Daniels, Pesticide Coordinator, WSU in Agrichemical and Environmental News, November 2001.


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The West Virginia University Cooperative Extension Service, U.S. Department of Agriculture and West Virginia counties cooperating. Equal Opportunity/Affirmative Action Institution.