18 | FEBRUARY 2002 Copyright© 2002, Belvoir Publications, Inc. TO SUBSCRIBE, CALL (800) 829-9165

BY KATHLEEN DUDLEY

Are “Spot-On” Flea Killers Safe?

TAbsolutely not, says our author, despite what the commercials say.

empting as it may be to simplisticallyconsider fleas as horrible insects, thebane of dogs everywhere, poisoningyour dog in a vain attempt to wipefleas out of existence doesn’t really

make sense. Even though more than half abillion dollars annually are spent on prod-ucts that kill fleas in that vain pursuit.

Of course fleas can make dogs (andeveryone else in the household) perfectlymiserable. But it’s not as if using toxic flea-killing chemicals is the only way to controlfleas. When we attempt to get rid of ourdogs’ fleas by utilizing chemicals that aretoxic to the brain and nervous system, thatmay disrupt hormone (endocrine) systems,and that cause cancer, it’s sort of like burningthe house down to get rid of ants – effective,sure, but what are you left with?

In the next issue of WDJ, we willdescribe effective, nontoxic methods of fleacontrol. No dogs (or any other members ofthe household) will get sick from thesemethods, and no dogs (or any other membersof the household) will die from them. Incontrast, dogs do get sick and die from thetoxic chemicals we will describe in thisarticle.

New products not saferAll pesticides pose some degree of healthrisk to humans and animals. Despite adver-tising claims to the contrary, both over-the-counter and veterinarian-prescribed flea-killing topical treatments are pesticides thatenter our dogs’ internal organs (livers, kid-neys), move into their intestinal tracts, andare eventually eliminated in their feces andurine. Not only that, but the humans andother household animals who closely inter-act with dogs who have been treated withthese chemicals can be affected by the tox-ins. What happens to the health of all ex-posed individuals during this systemic ab-sorption and filtration process varies fromanimal to animal, but the laboratory and fieldtrial results clearly indicate toxicity on thechronic and acute levels.

Until recently, foggers, flea collars,

exposed. We cannot make informed indi-vidual decisions on the acceptability of thoseexposures, a basic element in the mainte-nance and protection of our own health.”Spitzer adds, “The requirements for market-ing a new product fall considerably short ofproviding safety for our animal and humanfamilies.”

Active and inert ingredientsTo fully understand the risks associated withany of these products, it is important to un-derstand the various components in a fleaproduct, or any chemical product that youmay buy, for that matter.

Like other chemical products, all fleaproducts are made up of “active” and “inert”ingredients; strangely, the actual definitionsof those phrases are very different from whatthey seem to connote. In the case of flea-killing chemicals, the “active” ingredientdoes, in fact, target and kill fleas – but someof the “inert” ingredients are poisons, too.

While the word “inert” suggests benignactivity and even connotes safety in theminds of many consumers, legally, it simplymeans added substances that are not theregistered “active” ingredient. This isimportant because most people assume thatonly the “active” ingredient in a chemical

CONSUMER ALERT

powders, sprays, shampoos, and dipscontaining organophosphates (chlorpyrifos,malathion, diazinon), pyrethrins, syntheticpyrethroids, and carbamates, were thecutting-edge solutions to our flea problems.They were effective, but unfortunately, theyalso caused disease and sometimes death.Given enough time, most pesticideseventually cause enough human and animalinjuries that they are identified as hazardsand are removed from the market.

While the newest flea products – so-called “spot-on” liquids that are appliedmonthly to a dog’s skin – are being marketedaggressively by the manufacturers andveterinarians and represented as safealternatives to their predecessors, the factis, they are simply newer. All the “active”ingredients in these spot-on preparations –imidacloprid, fipronil, permethrin,methoprene, and pyriproxyfen – have beenlinked to serious health effects in laboratoryanimals (see chart, page 20).

“The public must recognize that any de-cision to use a pesticide, or to otherwise beexposed to pesticides, is a decision made inignorance,” says Eliot Spitzer, AttorneyGeneral of the New York EnvironmentalProtection Bureau. “We do not know theidentity of the chemicals to which we are

“Spot-on” flea-killers ar“Spot-on” flea-killers ar“Spot-on” flea-killers ar“Spot-on” flea-killers ar“Spot-on” flea-killers areeeeeefefefefeffective, but the long-terfective, but the long-terfective, but the long-terfective, but the long-terfective, but the long-termmmmm

efefefefeffects of their constant use isfects of their constant use isfects of their constant use isfects of their constant use isfects of their constant use isunknown. In efunknown. In efunknown. In efunknown. In efunknown. In effect, our dogsfect, our dogsfect, our dogsfect, our dogsfect, our dogs

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CONSUMER ALERT

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product is of concern. Many people feelcomforted by the idea that a product containsonly a minuscule amount of an “active”ingredient and up to 99.9 percent “inert”ingredients – a typical formula in manypesticide products. Actually, this makeupshould frighten consumers.

Why? Because the Environmental Pro-tection Agency (EPA, the governmentagency that oversees the pesticide industry)requires a higher (if not high enough) stan-dard of scrutiny for “active” ingredients;these must undergo a battery of tests to de-termine their toxicological profiles, be reg-istered with the EPA, and be listed on theproduct inserts and packaging. In contrast,“inert” ingredients need not be listed on theproduct inserts and packaging and are sub-ject to much less testing than the “active”ingredients; “inerts” are generally tested inshort-term studies for acute toxicity only.

The word “inert” implies chemicals thatare somehow inactive. In actuality, many“inert” ingredients used in pesticides areas toxic, or more toxic, than the registered“active” ingredients. For example, naphtha-lene, one of the “inerts” in an imidaclopridproduct, showed clear evidence of canceractivity through inhalation (nasal cancers),as well as anemia, liver damage, cataracts,and skin allergies. An unidentified “inert”ingredient in the flea product Advantage wasimplicated in the death of kittens who re-ceived doses within laboratory tolerances.

Why don’t pesticide manufacturers haveto disclose all the ingredients in their prod-ucts? This kettle began brewing in 1949,when the U.S. Congress passed the FederalInsecticide, Fungicide, and Rodenticide Act(FIFRA), allowing manufacturers confiden-tiality on issues they claimed would other-wise make them vulnerable to market com-petition. “Inert” ingredients, in other words,became protected by industry as “trade se-crets.” While protecting industry, this actsupersedes the public’s right to know to whatwe are being exposed and the health haz-ards resulting from these exposures. Andwithout full disclosure, we are unable tomake educated decisions as to which chemi-cals we want to avoid.

Laboratory studiesObviously, products undergo testing in or-der to qualify for EPA registration, and pre-sumably, most of the overt dangers a prod-uct can exert are ameliorated before theproduct can be marketed. Scientists usehealthy, adult, genetically identical mam-mals to test pesticides, and then extrapolatehealth information regarding the safety ofthe product to domestic animals and humanbeings. In the case of flea products, the labo-ratory tests are performed on live mice, rats,cats, and dogs.

These toxicological (poison) studies areperformed to establish the LD 50 – the oraldose at which the product would kill 50 per-

cent of a test population – and to determinethe acute and chronic effects. Throughoutand following the test, subjects are killed inorder to study the specific system damage(lungs, kidney, etc.). Acute disease tests,such as nervous system and skin reactions,can be performed over a relatively short timeperiod. Most studies are conducted for 3-,13-, or 52-week intervals, and use exagger-ated dosages to compensate for the shorttesting periods.

“Because of the short period under whichthe studies are conducted, the health effectsresulting from the higher doses of the chemi-cals are relevant,” says Dr. Virginia Dobozyof the EPA’s Pesticide Division. These ef-fects can include head-nodding; facialtwitching; exaggerated blinking; gag re-sponses; weight increase of the spleen, thy-mus, and adrenal glands; and/or atrophy ofthe thymus.

Long-term studies, needed to understandthe chronic effects of the pesticides, are fewby comparison. Chronic disease such as can-cer, immune suppression, developmental orreproductive damage, and DNA damage cantake months or years to manifest.

However, the cumulative effect –potential damage from continued use of onespecific pesticide product or multipleproducts over a dog’s lifetime – is unknown.Also unknown is the potential for synergisticeffects – combined impacts of chemicalexposures from their home and outdoorenvironments. Neither the cumulative northe synergistic effects of chemicals inproducts are required to be tested by the EPAbefore a product is made commerciallyavailable. So, our dogs may be morevulnerable to unknown chemical-relateddangers than the happy commercials wouldhave you believe.

Critics of the pesticide industry claimthat the EPA registers pesticides not onsafety, but on a cost-benefit basis, balanc-ing health and environmental concernsagainst the economic gain to the manufac-turer and the end user of the product. Buteven if the pesticide manufacturers and theEPA are not overly concerned about oursafety, we as consumers and guardiansshould be very concerned.

Too good to be trueToday, spot-on flea preparations are consid-ered by many as the Rolls Royce of fleaproducts, and sell swiftly in veterinary clin-ics and pet stores. Each of the makers ofthese products claim that they are safe – saferthan ever – and that only the targeted in-sects will be affected by the products’ neu-

AdvantageBayer Corporation, Shawness Mission, KS(800) 255-6826 or nofleas.comActive ingred: 9.1% imidaclopridInert ingred: 90.9% (not disclosed)(MSDS indicate inerts include some solvents)

Adams Spot-on Flea & Tick ControlFarnam Pet Products, Phoenix, AZ(602) 285-1660 or farnam.comActive ingred: 45.0% permethrinInert ingred: 55.0% (not disclosed)

BioSpot Flea & Tick ControlFarnam Pet Products, Phoenix, AZ(602) 285-1660 or farnam.comActive ingred: 45.0% permethrin

5.0% pyriproxyfenInert ingred: 50.0% (not disclosed)

Defend EXspot TreatmentSchering-Plough Animal Health, Union, NJ(800) 842-3532 or www.sgp.com/main.htmlActive ingred: 65.0% permethrinInert ingred: 35.0% (not disclosed)

Spot-On Pesticides and Their Ingredients

Frontline Top SpotMerial Limited, Iselin, NJ(800) 660-1842 or frontline.comActive ingred: 9.7% fipronilInert ingred: 90.3% (not disclosed)(MSDS indicates inerts include ethanol7.7%, polyvinlpyrrolidone 6.9%,butylhydroxytoluene 0.3%,butlyhydroxanisole 0.3%, and carbitol[diethylene glycol monoethyl ether])(Note: Frontline Plus is essentially the sameas Frontline Top Spot, but with the additionof 8.8% methoprene, an IGR.)

Zodiac FleaTrol Spot OnWellmark International, Schaumburg, IL(800) 950-4783 or zodiacpet.comActive ingred: 45.0% permethrin

3.0% methoprene (IGR)Inert ingred: 52.0% (not disclosed)

20 | FEBRUARY 2002 Copyright© 2002, Belvoir Publications, Inc. TO SUBSCRIBE, CALL (800) 829-9165

rotoxic impacts. The products are frequentlyadvertised as safe for small children andadults as well as puppies (over eight weeks)and geriatric dogs. Do they sound too goodto be true? Well, perhaps they are.

The spot-on flea products fall into fourgeneral categories of insecticides. All haveneurotoxic effects. The first three –imidacloprid (a chloro-nicotinyl insecti-cide), fipronil (a phenylprazole insecticide),and permethrin (a synthetic broad spectrum

pyrethroid insecticide) – all work by disrupt-ing the nervous system of insects, killing bycontact or ingestion. The fourth type con-tains insect growth regulators (IGR), whichdon’t kill, but interrupt the flea’s life cycle.

Imidacloprid is the first of its class ofinsecticides, and is relatively new on theblock; it was introduced in 1994. Labora-tory testing on mice, dogs, and rats, indi-cates that this insecticide can be neurotoxicto laboratory animals, causing incoordina-

tion, labored breathing, thyroid lesions, re-duced birth weights, and increased fre-quency of birth defects.

Fipronil was introduced in the UnitedStates in 1996. It is a neurotoxin and sus-pected human carcinogen. Fipronil cancause liver toxicity, thyroid lesions (cancer),damage to the kidneys, increased cholesterollevels, alterations in thyroid hormones, in-coordination, labored breathing, increasedmiscarriages, and smaller offspring.

Fipronil

Imidacloprid

Methoprene

Permethrin

Pyriproxyfen

Ethanol

Butylhydroxanisole

Butyldydroxytoluene

Carbitol

Polyvinlpyrrolidone

Active

Active

Active

Active

Active

Inert

Inert

Inert

Inert

Inert

Carcinogen

Organ damage

Neurotoxin(nervous systemdamage)

Teratogen(reproductive damage)

Skin problems

Carcinogen

Organ damage

Neurotoxin

Teratogen

Organ damage

Neurotoxin

Carcinogen

Organ damage

Neurotoxin

Teratogen

Autoimmune

Teratogen

Teratogen

Carcinogen

Carcinogen

Neurotoxin

Organ damage

Carcinogen

Thyroid cancer (possible human carcinogen)

Increased organ weights, altered thyroid hormones

Loss of appetite, underactivity, convulsions, whining, barking, crying(vocalization), body twitches/tremors, overactivity, salivation, stiffened limbs,unsteady gait, incoordination, labored breathing

Reduced fertility, decreased litter size and body weights in litters, fetus mortality

Severe moist inflammation, ulcerations, skin sloughing, chemical burn, itching,hair loss at and beyond the application site

Yet to be determined; evidence of thyroid lesions in dogs

Liver, kidney, thyroid, heart, lungs, spleen, adrenal, brain, gonads; liver toxicity,increased organ weights, thyroid lesions, increased cholesterol levels in dogs

Incoordination and labored breathing, muscle weakness including musclesnecessary for breathing

Increased miscarriages and smaller offspring

Liver enlargement

Headaches, eye and throat irritation, difficulty breathing, confusion, dizzinessand nausea in humans

Liver and lung tumors (possible human carcinogen)

Kidney enlargement, changes in lung

Tremors, incoordination, elevated body temperature, increased aggressivebehavior, learning disruption

Fertility is affected

Bone marrow changes in laboratory animals

Reduced weight gain, toxicity to pups

Adverse effects on fetus

Animal carcinogen (possible human carcinogen)

Animal carcinogen (possible human carcinogen)

Headache, depression, nausea, vomiting, diarrhea, abdominal and lumbar pain

Pathological lesions in brain, lungs, liver menni; possibility of pulmonary edema,intravascular hemolysis and bone marrow depression

Not evaluated by EPA for carcinogenic

INGREDIENT TYPE AFFECTED SYSTEM LABORATORY ANIMAL HEALTH EFFECTS

Adverse Effects of Ingredients Found in Spot-On Products

Sources of the above information include reports from the Environmental Protection Agency; Occupational Safety & Health Administration, US Dept. of Labor; Extoxnet:Extension Toxicology Network; Journal of Pesticide Reform, Material Safety Data Sheets, Pesticide Action Network North America, and more.

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In a review of the fipronil pet formula-tions, Dr. Virginia Dobozy of the EPA’s Pes-ticide Division states that “this is a persis-tent chemical that has the potential for ner-vous system and thyroid toxicity after longterm exposure at low dosages.”

Permethrin, a synthetic broad spectrumpyrethroid insecticide, is suspected to be anendocrine disrupter and a carcinogenic in-secticide (causing lung cancer and liver tu-mors in laboratory animals). Somepermethrin products have additional “ac-tive” ingredients in lesser percentages, andinclude methoprene, and pyriproxyfen (de-scribed below).

Methoprene and pyriproxyfen are bothinsect growth regulators (IGR), which limitthe development of juvenile fleas so theycannot reproduce. Test results indicate thatmethoprene causes enlarged livers and de-generation of parts of the kidneys.

All of the above active ingredients haveinduced responses in laboratory animals thatgive cause for alarm. While these new prod-ucts are suggested as safer than their prede-cessors, they indicate high levels of acuteand chronic poisoning from short-term use.

Method of actionWhether or not it is purposeful, manufac-turers of these spot-on flea products havemanaged to convince many veterinariansand animal guardians that these products arenot absorbed into our dogs’ systems. The

companies’ literature describes in vague andcontradictory detail how the chemicals don’tgo beyond the hair follicles and fat layers ofthe dogs’ skin.

Take, for example, information pub-lished on Merial’s Web site for Frontline(“How Frontline Works”). In one place, itclearly states that fipronil (Frontline’s “ac-tive” ingredient) is absorbed into the skin

(“Sebaceous glands pro-vide a natural reservoirfor Frontline . . .”), butother statements suggestthat fipronil stays thereand then leaves throughthe same entry point with-out moving into any other

parts of the dog’s body – an illogical con-clusion.

When the EPA’s Dr. Dobozy reviewedthe results of a fipronil metabolism study,she reported that “significant amounts of ra-dio-labeled fipronil were found [not only]in various organs and fat . . . [but they werealso] excreted in the urine and feces, andwere present in other parts of the body . . .which demonstrated that the chemical isabsorbed systemically.”

Veterinarians and pet owners who payclose attention can witness evidence thatthese products are indeed systemically ab-sorbed. Dr. Stephen Blake, a San Diego vet-erinarian, relates a client’s experience: “Weput Advantage on the backs of our dogs and

could smell it on their breath in a matter ofminutes following the application.” Blakestated that this indication of immediate ab-sorption did not tally with what he had beenled to believe by reading Bayer’s literature.He continues to question its safety for hisclients’ animals.

Neurological health effectsLogic tells us that a topical chemical that isnot absorbed into the skin has no chance ofcausing neurotoxic effects. Then why do theMaterial Data Safety Sheets (MSDSs) forall the permethrin-containing pesticides rec-ommend preventing their products from hav-ing prolonged contact with the skin? Andwhy do they all state that skin sensations,such as “numbness and tingling,” can oc-cur? Schering-Plough’s MSDS makes an ad-ditional statement about its Defend EXspotTreatment: “can be harmful if absorbedthrough the skin and harmful following in-halation,” causing headaches, dizziness, andnausea.

Bayer does not reveal more than 90 per-cent of the ingredients in Advantage, but itsMSDS does warn us to “use a respirator fororganic vapors” in order to avoid “respira-tory tract irritation and other symptoms suchas headache or dizziness” (symptoms ofnervous system exposure). Bayer’s promo-tional literature for Advantage, however,states that “studies prove that using 20-24times the dosage on dogs and cats does notcause any internal or external side effects,”and that “. . . switching to Advantage fromanother flea control product poses virtuallyno risk to your pet.”

Dr. Graham Hines, a veterinarian fromthe United Kingdom, treated a four-year-oldfemale German Shepherd who had two Ad-vantage Top Spot treatments. He reportedthat “both times she became unusuallyclingy, and would not leave her guardian’sside, yet paced up and down all day, veryrestlessly. These symptoms persisted for 48hours before a gradual return to her normalstate.” The neurotoxic effects were clear toDr. Hines.

Dr. Blake also finds different results thanthe Bayer literature. “We are told that theproduct affects only insects’ nervous sys-tems, not mammals’. Several of my clientstold me that they accidentally got someAdvantage on their hands and when theytouched their mouths, their lips became im-mediately numb for several hours. So muchfor not having an effect on the nervous sys-tem of mammals.”

Acute symptoms of headache, nausea,and abdominal and lumbar pain are associ-

Don’Don’Don’Don’Don’t just “consult yourt just “consult yourt just “consult yourt just “consult yourt just “consult yourveterinarian.” Wveterinarian.” Wveterinarian.” Wveterinarian.” Wveterinarian.” We woulde woulde woulde woulde wouldsuggest NEVER using onsuggest NEVER using onsuggest NEVER using onsuggest NEVER using onsuggest NEVER using on

“debilitated, aged, medicated,“debilitated, aged, medicated,“debilitated, aged, medicated,“debilitated, aged, medicated,“debilitated, aged, medicated,prprprprpregnant or nursing” dogs.egnant or nursing” dogs.egnant or nursing” dogs.egnant or nursing” dogs.egnant or nursing” dogs.

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List of “active”List of “active”List of “active”List of “active”List of “active”(known) and “iner(known) and “iner(known) and “iner(known) and “iner(known) and “inert”t”t”t”t”(who knows what?)(who knows what?)(who knows what?)(who knows what?)(who knows what?)

ingringringringringredients.edients.edients.edients.edients.

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When rWhen rWhen rWhen rWhen researesearesearesearesearchingchingchingchingchinga chemical, usea chemical, usea chemical, usea chemical, usea chemical, usethe EPthe EPthe EPthe EPthe EPAAAAARegisterRegisterRegisterRegisterRegisteredededededNumberNumberNumberNumberNumber.....

22 | FEBRUARY 2002 Copyright© 2002, Belvoir Publications, Inc. TO SUBSCRIBE, CALL (800) 829-9165

Kathleen Dudley is a writer andphotgrapher, and lives in New Mexico.

ated with carbitol, one of the “inert” ingre-dients in Frontline. According to the MSDS,carbitol induced these symptoms in labora-tory settings.

Curiously, these potential side effects arenot published in the literature accompany-ing the products, nor do many veterinariansknow the dangers. But there are numerousanecdotal reports from veterinarians in theU.S. and the U.K. of dogs who were treatedwith spot-on products who have displayedsigns of neurological damage, such as de-pression, lethargy, convulsions, underactiv-ity, tremors, overactivity, stiffened limbs,and lameness.

Adverse skin effectsTopical skin irritation is listed on all theMSDSs of the products reviewed in this ar-ticle; however, product literature inserts failto emphasize the extreme nature of the prob-lems. They all instruct the users that theirproducts are for “external use only,” and to“avoid contact with the skin,” but onlyMerial’s product insert appears to suggest

there is some possibil-ity of adverse skin con-tact reactions.

Dr. Dee Blanco, aholistic veterinarianpracticing in NewMexico, treated 20dogs for adverse reac-

tions to Farnam’s flea product. In a letter tothe Farnam regarding a client who had usedone of Farnam’s permethrin-based insecti-cides, Dr. Blanco stated, “All the dogs (20out of her 24 dogs treated with BioSpot )had pruritus (severe itching of the skin) withbleeding and cracking of the skin, variousdegrees of erythema (intense redness of theskin), many fluid vesicles (blisters), severehair loss, and elephantiasis (thickening ofthe skin) with chronic itching. Many alsoshowed severe mental depression, lethargy,and symptoms concomitant with aggravatedliver toxicity. All symptoms appeared withintwo weeks after applications of your(BioSpot) product, also a consistent time-frame for liver toxicity after absorptionthrough the skin. . . To date, most of the dogshave dramatically improved but a few stillremain symptomatic.”

Dr. Blanco also stated that one dog diedof liver cancer within three months of thisBioSpot application, which she says “couldhave been exacerbated by the applicationof BioSpot.” Permethrin is indicated as apossible carcinogen by the EPA, causingliver enlargement and cancers in laboratorymammals.

When Dr. Dobozy reviewed the reportsfrom fipronil product studies, she found thatFrontline “does not adequately describe thesevere reactions” reported by veterinarians– sloughing, “chemical burn” conditions,and extensively affected areaswell beyond the application site.When these incidents were re-ported, Merial recommendedbathing the dogs. That’s strange,because their literature indicatesthe product remains effective after bathing.

The MSDS for Bayer’s Advantage tellus that “prolonged contact with the skin cancause defatting of the skin due to solventcomponent in the products,” to “avoid skincontact,” “to wear appropriate gloves whenhandling the product,” and to “wash off anycontamination.”

Chronic diseaseBased upon toxicological studies, a dog suf-fering from liver, kidney, thyroid, adrenal,spleen, lung, brain or gonadal conditionscould experience heightened states ofchronic diseases, with the potential for de-velopment of cancer, when spot-on fleapreparations are used. Permethrin is linkedto malignant liver and lung tumors and au-toimmune system disease, and at very lowlevels suppresses the immune system. Thy-roid lesions have developed in laboratorystudies in dogs during imidacloprid tests.Further studies are necessary to understandthe possibilities of malignancy. Thyroid can-cer has been linked to fipronil, according tothe EPA. The data from the metabolism andchronic toxicity studies for fipronil indicatethat “ . . . this is a persistent chemical andhas the potential for nervous system and thy-roid toxicity after long-term exposure at lowlevels,” according to Dr. Dobozy.

In the Journal of Pesticide Reform, au-thor Caroline Cox cites studies that showthyroid sensitivity to imidacloprid can re-sult in thyroid lesions, as well as increasedincidences of miscarriages, mutagenic(DNA damage) abnormalities, and abnor-mal skeletons in animal studies. In addition,one metabolite (breakdown of the chemicalinto new chemical compounds during themetabolism process in the body) ofimidacloprid appears to be far more toxicto mammals than the imidacloprid itself.

General risk factorsOf course, not all dogs exhibit immediatelynoticeable symptoms when dosed with acommercial spot-on flea product. Adult ani-mals and those in the peak of health are lesslikely to show immediate signs compared

to animals that are young, old, or sufferingfrom chronic disease. Animals with a height-ened sensitivity to chemicals or with expo-sures from multiple sources such as a fleacollar; other dips, sprays, dust, or flea

bombs; yard pesticides; andhouse termite extermination,are most likely to react. Thecumulative and synergisticimpacts of pesticides cantake a heavy toll on animals.

Dr. Jerry Blondell, of the US EPA Of-fice of Pesticides, has indicated clearly “notto use pesticides on the old, the sick, or theyoung.” While some of the literature for thespot-on products does discourage this us-age, many dog guardians and veterinariansoverlook or disregard these written precau-tions.

Although the number of dogs reportedto react to these products may seem small,this does not suggest the overall impact issmall. First, spot-on products are relativelynew, and many problems are cumulative.

Second, reactivity to chemicals in apopulation is similar to other population sta-tistics and is represented by a bell-shapedcurve. In other words, at one end of the spec-trum are sensitive individuals, and at theopposite end are resistant individuals; thesegroups are relatively small compared to thevast middle group, who show varying de-grees of susceptibility – but who are all sus-ceptible. Thus the sensitive group – dogswho have displayed signs of toxicity – hap-pen to be the sentinels for the younger,healthier ones who will eventually be af-fected; it’s just a matter of time.

Safe alternativesIntegrated pest management (IPM) is a non-toxic approach used to eradicate any insectinfestation. Simply, it is a way of thinkingabout how to preserve the quality of life onthis planet and within the earth’s stratosphere– of understanding not only the damages ofthe pesticide to all species and the environ-ment, but also understanding the conse-quences of insect resistance to the constantparade of new, more sophisticated, and per-haps more toxic pesticide formulas. TheIPM process was initially designed to safe-guard all species, including the environment,from the ravages of pesticides.

In the next issue, we will present acomplete indoor and outdoor IPM treatmentprogram for effective, non-poisonous fleacontrol.