"Spot-Ons" are advertised heavily, recommended by trusted veterinarians and represented as safer,
easier to use alternatives to the older pesticides.
But is the new mix of neurotoxins really safe for pets and your family?
Organo phosphates (aka Chlorpyrifos, Diazinon, Dioxathion and Malathion) and carbamates (aka Carbaryl, Methomyl and Propoxur) were among the original chemicals in flea/tick treatments. Both work by interfering with the transmission of nerve signals. Unfortunately these effects are not confined to the pests but eventually caused enough animal damage and death, that the EPA removed some of them from the US marketplace.
Many of these ingredients are still used in flea collars and flea bombs.
These were replaced by the "Spot-On" treatments.
They are represented by four general categories of insecticides.
The active ingredients of three of them (imidacloprid, fipronil, permethrin) work by disrupting the nervous system of insects.
The fourth type, whose active ingredients are methoprene and pyriproxyfen insect growth regulators (IGR).
They don't kill but interrupt the flea's life cycle.
These insecticides are promoted as being absorbed into the skin layer where they stay as a reservoir.
Results of radio-labeling produce far different results demonstrating that the chemicals are absorbed systemically.
They were found in various organs and fat and also excreted in urine and feces.
Though supposedly safer, all of these ingredients have been associated with laboratory animal health defects.
The severity of reactions to these new insecticides range from:
- minor skin irritation, skin sloughing, hair loss
- body twitches/tremors
- nausea, vomiting, diarrhea, abdominal and lumbar pain
- whining, barking, crying
- lack of coordination from stiffened limbs, unsteady gait
- organ damage to liver, kidney, heart, lungs, spleen, adrenals, brain, gonads
- increased miscarriages and smaller offspring
- elevated aggressive behavior, learning disruption
- animal carcinogen and possible human carcinogen
These responses are cause for alarm indicating high levels of acute and chronic poisoning from even short-term use.
There has not been sufficient time to evaluate long-term cumulative use.
Also unknown is the potential for synergistic effects from the combined impact of multiple exposures to different chemicals.
The corporate and federal response to these risks has been to amend the product label to include:
- Additional dosing information,
- Distinguishing between cat and dog products,
- Improving label clarity and
- Addressing uncertainties about inert ingredients.
While these recommendations are worthwhile and necessary to provide more information to the consumer they miss the underlying problem.
It is not the product label but the products ingredients that cause harm.
Even following these new label directions is not sufficient.
Pyrethrin, permethrin and phenothrin can cause severe adverse reactions in cats and ferrets.
These are recommended for use on dogs only, but in mixed pet households cats receiving secondary exposure via contact with treated dogs are suffering from the effects.
Many organizations (NRDC, HSUS, HSVMA) including the EPA are questioning the short and long-term effects of their use.
Our pets have become often-unwilling test subjects.
Not every pet exhibits symptoms from these "Spot Ons".
Adult healthy animals are less likely to manifest problems compared to animals that are very young, old, or suffering from chronic disease.
As a pet guardian you need to evaluate benefits and risks of pesticides.
This should include acknowledging the consequences of increased insect resistance to ever expanding, more complicated and possibly more toxic pesticide formulas.
If you do decide to use flea and tick products, follow these simple steps to help prevent problems:
- Never use dog treatments on cats, and vice versa
- Always be certain of your pet's weight before purchase to ensure proper dosage
- Don't split one "large dog" dose in half for two small dogs (or combine two "small dog" doses for one large dog)
- Read and follow all instructions when using these products
- Do not use these products on elderly or pregnant animals
How to tell if your pet has been poisoned:
Symptoms of poisoning by flea/tick treatments may include salivating, dilated pupils, tremors, vomiting, hiding, shivering, and skin irritation.