In December 2001, we adopted a
one and a half year old Dalmatian,
named Hamish.  He had been in a
high kill shelter in New York City,
and was rescued just one day before
he was scheduled to be destroyed. 

To protect him from fleas and ticks,
our vet recommended Frontline - a
liquid that is applied to the dog's
back.  It gave us peace of mind
knowing that he had this protection,
but it had to be purchased from a
veterinarian and was quite expensive. 

One day while shopping, I came
across an over-the-counter product,
called Bio Spot Flea & Tick Control 
(by Farnam Pet Products).  It looked
similar to the Frontline product, but it was much cheaper, so I decided to try it.  The Bio Spot seemed to work just as well as Frontline, so I used it again six weeks later. 

An hour after applying the Bio Spot, I found Hamish thrashing about on the ground.  His body was completely stiff.  His head was raised in the air, and his jaws were opened wide.  A thick foamy saliva was spewing from his mouth.  Horrified, I tried to determine if something was stuck in his throat.  His windpipe was clear, but he was not breathing.  His eyes began to roll back in his head.  He was dying and I did not know what to do to save him.  We made a desperate call to our veterinarian.

What to do if your pet is having an adverse reaction to a flea control product


                                        CONTACT YOUR VETERINARIAN IMMEDIATELY.

After a few minutes, Hamish slowly began to recover.  We had just witnessed something we had never
seen before - a grand mal (severe) seizure.  Our veterinarian said that a blood test might help to find the cause, and mentioned the possibility of epilepsy.  By the afternoon, Hamish looked much better, but that
night he endured three more grand mal seizures.

Why would a healthy dog have four grand mal seizures within twenty hours?  I searched the Internet for information on epilepsy, and read that if seizures begin to occur frequently, the animal may have to be euthanized!  We would not know the results of the blood test for a week, but we had a feeling it was
not epilepsy, and wondered if the seizures were caused by the Bio Spot.

It seemed unlikely that Bio Spot could have caused the seizures because we had used it (same batch) just six weeks earlier with no adverse effects.  Also, the packaging did not list seizures as a possible adverse reaction (it listed only lethargy, itchiness, redness, rash, hair discoloration, or hair loss).

Just in case the seizures were caused by the Bio Spot, we thoroughly washed Hamish to remove as much
of it as possible, and took him to our veterinarian for a physical exam and blood test.  The exam showed that everything was normal, and the blood test revealed no internal problems.  Our veterinarian could not rule out BioSpot as the cause of the seizures.

Hamish has not had any seizures since the Bio Spot was thoroughly washed off three weeks ago, and appears to be in good health.  However, we worry about irrepairable damage that may have been done to his neurological system, and wonder if short-term exposure to the chemicals in BioSpot will cause any long-term health problems.

How Bio Spot Works

According to Farnam's website, the ingredients in Bio Spot "move around your dog's coat by several processes including diffusion and capillary action, and transfer from hair to hair as the pet moves."  That
may lead you to believe that it remains on your dog's coat, therefore it's safe for your dog.  The truth is these chemicals are absorbed through the skin and enter the bloodstream.  That is also how transdermal patches work - they use the skin as a way to enter the body.

The main active ingredient in Bio Spot is a pesticide known as permethrin  (it is also found in many similar products, including Bayer's K9 Advantix and Summit VetPharm's Vectra 3D).  It kills insects by paralyzing their nervous system (that is also how nerve gas works).  However, it cannot distinguish between an insect's nervous system, a dog's nervous system, or a human's nervous system. That is why it is important to wash your hands thoroughly with soap and water after handling.

Serious Risk to Health

While never claiming their Bio Spot product is safe for dogs, the Farnam website states, "Nearly all dogs tolerate Bio Spot well."  However, that does not mean it is safe for ANY dog, or for anyone who comes in contact with a recently treated pet.  According to the Natural Resources Defense Council:

"Many and perhaps most Americans believe that commercially available pesticides, such as those found in pet products, are tightly regulated by the government.  In fact, they are not. Not until the passage of a 1996 law focused on pesticides in food did the Environmental Protection Agency (EPA) begin examining the risks from pesticides in pet products in earnest.  To this day, the EPA allows the manufacture and sale of pet products containing hazardous insecticides with little or no demonstration that a child's exposure to these ingredients would be safe.  Just because these products are on store shelves does not mean they have been tested or can be presumed safe."

"Of course, as bad as these products may be for pet owners and caregivers, they often are worse for the pets themselves.  Based on the very limited data available, it appears that hundreds and probably thousands of pets have been injured or killed through exposure to pet products containing pesticides. As with small children, pets cannot report when they're being poisoned at low doses."

                                      Natural Resources Defense Council
                                      Health Hazards from Flea and Tick Products (Executive Summary)
                                      November, 2000

What is known about Bio Spot's main active ingredient, permethrin?  A few drops of it can be deadly
to a cat.  Toxicological studies have linked this pesticide to serious acute and chronic health effects.  The EPA has classified it as a possible human carcinogen because it increases the frequency of lung and liver tumors in laboratory animals.  It suppresses the immune system.  Permethrin is also suspected to have played an important role in the development of illnesses known as the Gulf War Syndrome.

In a recently published journal entitled, Experimental Neurology, researchers at Duke University Medical Center found that frequent and prolonged use of permethrin on adult rats lead to cell death in their brains. In another recent study, researchers at Virginia Tech found that low-level exposure to permethrin caused changes in the brain that could lead to Parkinson's Disease.

The inert ingredients in Bio Spot, which are not disclosed, may pose an even greater risk because they
receive much less scrutiny by the EPA.  The cumulative and synergistic effects of these chemicals are not required to be tested for safety.

Is it true that nearly all dogs tolerate Bio Spot well?  Perhaps, but the risk of short-term exposure includes severe adverse reactions, and the risk of long-term exposure is unknown.

Posted:  July, 2002

James TerBush is a designer of educational games and lives in Pennsylvania.


What can I do to help get harmful pet products
removed from the market? 

1.  Report adverse reactions to the National Pesticide Information Center at                     
       1-800-858-7378.  The NPIC is open seven days per week from 6:30am - 4:30pm
       PST.  They maintain a database of adverse pesticide incidents for the EPA.  
2.  Also, report adverse reactions to the manufacturer of the product.  Their
       phone number is on the product packaging, or you can find their phone number
       by clicking hereSeek reimbursement for veterinary expenses related to
       adverse incidents.

       3. Urge veterinarians or their staff to report adverse incidents using the NPIC's                          Veterinary Pesticide Incident Reporting portal. 

       4. Join a class action lawsuit or consider filing a case in small claims court.


  “If a huge skull and crossbones were suspended above the
insecticide department the customer might at least enter it with
the respect normally accorded death-dealing materials.” 
Rachel Carson, Silent Spring  


"There are 'critical periods' in human development when
exposure to a toxin can permanently alter the way an
individual's biological system operates.”
U.S. Environmental Protection Agency


“The use of any product on the market to control fleas
on pets is associated with a degree of hazard to the animal.”
Claude Kissin, Vice President, Hartz Mountain Corp., 1987


"They are available in grocery stores, pharmacies, feed
stores, veterinary clinics and pet stores.  They are often poorly
labeled and lacking adequate instructions for their safe use."
EPA Overview of Pet Pesticide Products, August 1996


"There is no perfect measurement technique for
determining the amount of pesticide exposure, nor is
there a perfect method for determining risk."
J. Scott Boone, Mississippi State University, Nov. 2001


"During fetal development and the first years of life,
infants are much less able to detoxify most pesticides and
are uniquely vulnerable to developmental toxins, especially
neurotoxins, given that the brain and nervous system
continue developing through about age 12."
Charles M. Benbrook, 2003


“Given the wide range of commonly used home and garden
products associated with health effects, the College's
overall message to patients is to avoid exposure to all
pesticides whenever and wherever possible.”
The Ontario College of Family Physicians, April 2004


Synthetic insecticides, although effective, have been
known to cause environmental effects that are harmful
to humans and to the companion animal.
Sergeant's U.S. Patent Application 20080118585, Oct. 2007


"Pesticides that can cause cancer, alter genes, and damage
the reproductive, endocrine or nervous system must no longer
be authorised. Pesticides that harm bees or life in aquatic
environments must be banned from the market."
Manfred Krautter, Greenpeace chemicals expert, 2008


“The steady rise of reported toxicities to spot-on products
with pets underscores the potential health implications
of chronic human exposure."
    Nicholas Halbach, DVM, Director Hesperian Group, 2009   


"Understanding the potential exposure to humans
resulting from contact with pets treated with
topical health products is critical."
Bayer Animal Health, to FIFRA Science Advisory Panel,
October 6-9, 2009


“I think it’s a good idea to minimize pesticide exposure
of any sort, not only because of what we know,
but because of what we don’t know.”
Donald Weston, UC Berkeley, February 2010


"Over time, repeated nerve stimulation can lead to other
neurological symptoms, and this is why pyrethroids
are cited as a possible cause of ADD, ADHD, Parkinson's,
Bell's palsy and even Alzheimer's disease."
Jeanne Roberts, freelance environmental writer


"Risk management and other traditional concepts of
chemicals control have proven inadequate to protect
human health and the environment.  Modern policies
must be based on knowledge and precaution -- not
on chance."
ChemSec - The International Chemical Secretariat


"We are almost like a third world country when it
comes to regulating chemicals."
Frederick vom Saal, the Endocrine Society

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