Fipronil in parts-per-trillion can mutate proteins and kill human liver cells.
Fipronil was introduced for commercial use in the U.S. in 1996.
It was praised as a safer insecticide by targeting invertebrates but not vertebrates.
Safer for humans and pets, supposedly.
Fipronil kills an insect by disrupting its central nervous system.
The chemical acts selectively on the insect’s GABA and glutamate receptors.
The mechanism for this 'selectivity' is not completely understood.
Research now shows that even minuscule exposure is toxic to vertebrates including humans and pets.
The mechanism is excitotoxic.
Fipronil has been shown to mutate proteins and to kill human liver cells at concentrations of 0.1 nM.
Using fipronil's molecular weight = 437.15 g/mol leads to
That is a ~very~ low exposure.
Meanwhile, the government allows fipronil residue in foods at levels 220x to 34,000x higher.
The researchers noticed that the dose-response curve was non-monotonic.
In other words, the smallest doses were more toxic than larger ones (see hormesis for more about this kind of toxic behavior).
Also, the researchers found that fipronil sulfone, a chemical left over after fipronil breaks down, was more toxic than fipronil itself.
Fipronil sulfone caused cell death at lower doses.
FrontLine (by Merial, a joint venture between Merck and Aventis) is a popular flea and tick treatment for pets.
It contains 9.8% fipronil by weight.
FrontLine is applied topically between the pet's shoulder blades. Fipronil collects in oils from skin and hair follicles and migrates across the pet's body.
Usually 98-100% of any fleas or ticks die within 24-48 hours.
This toxic action lasts for approximately 30 days.
This study found that, one day after applying FrontLine to an adult dog, petting it for just 5 minutes while wearing gloves resulted in exposure of 600 ppm.
Typical owners handle their pets more than 5 minutes per day.
Any surface the pet contacts will become contaminated, thereby increasing exposure.
Dander will also remain toxic for a period.
Children and anyone suffering an excitoxin-related illness are at higher risk.
Veterinarians and other pet care providers also have increased risk.
Fipronil is extremely toxic to termites and has gained popularity for use around commercial, residential, hospital, and school grounds.
Termidor SC (TSC) is sold for this purpose.
According to the label it contains 9.1% fipronil by weight. Additional information includes
|0.8 lb fipronil / 1 gal TSC||Fipronil concentration|
|0.8 oz TSC / gal H2O||Typical application|
|1.6 oz TSC / gal H2O||Severe infestation|
|3.2 oz TSC / gal H2O||Severe infestation and soil won't accept labeled volumes|
|1.06 g TSC / mL TSC||Specific gravity of TSC|
|0.9982 kg H2O / L H2O||Specific gravity of water @ 20°C|
Calculating for undiluted Termidor
Calculating for the fipronil concentration in a typically diluted application
Similarly, the concentration for a severe infestation is 26,000 ppb, and for a severe infestation in non-absorbant soil it is 51,000 ppb.
Fipronil degrades slowly on vegetation (half-life of 7.3 months depending on substrate and conditions) and relatively slowly in soil and in water (half-life can accelerate to 36 hours in water and sunlight).
Desulfinyl fipronil and fipronil sulfone are two of the chemicals left over after fipronil decays.
They result from photodegradation, biotransformation or oxidization mechanisms.
Both of these chemicals are more toxic than fipronil itself.
They are also very persistent in the environment.
A study on mice found that fipronil poisoning caused excitation in the central nervous system, leading to damage in nerve cells related to the over-expression of glutamate transmitters.
This is evidence of excitotoxicity.
In other studies where the animals survived, fipronil
Fipronil is applied to rice fields as an insecticide. The runoff was found to be highly toxic to crayfish.
Fipronil has been observed to bioaccumulate in fish, where some of it biotransforms into fipronil sulfone.
Fipronil is highly toxic to bees, with death resulting from 0.1 ng exposure. Bees are a critical link in the ecosystem. Fipronil (and imidacloprid) are implicated in Colony Collapse Disorder.
There is early evidence that some people are more susceptible to fipronil's toxic effects than others.
Fipronil is 1 of 16 pesticides selected to be monitored in a study sponsored by industry and planned by the EPA.
The study set out to pay families $970 to videotape their children after exposing them to pesticides and other dangerous chemicals for 2 years.
Intentions about the study leaked out, and after more than a year of pressure the EPA said it would not 'run' the study.
Although the EPA is no longer providing direct funding for the study, it is being undertaken as a 'private' study by the American Chemistry Council.
Children will still be intentionally exposed.
The study intends to use children from birth to age 3.
Fipronil is sprayed on crops such as corn and sunflower. This study found
• 35% converting to the metabolites which themselves are potent insecticides
This is troublesome since the interactions between fipronil, its metabolites, and other chemical residues have not been studied with regards to human toxicity.
Also, the EPA RfD for fipronil is 0.0002 mg/kg/day (0.2ppb).
That’s hundreds of times higher than levels known to cause harm.
• Concentrations found in the examples above
• High uptake into plants
• Persistence in the environment
• Tendency to bioaccumulate
• Neurotoxic effects at very low, non-monotonic doses
it is reasonable to conclude that fipronil should be regarded with considerable caution and awareness.
The following warnings found on the Termidor label should take on new gravity:
• Do not allow people or pets to contact contaminated areas
• Do not treat around edible plants
• Do not contaminate water supplies or while precipitation is occurring
• Toxic to birds, fish, and aquatic invertebrates
For additional information, the Fluoride Action Network is paying attention to Fipronil.
This site contains hundreds of first-hand accounts about pets that have suffered adverse reactions — including death — from pesticide treatments.
Using Natural Defense? Look here for observations about its toxicity...
It is not made with fipronil but acts in a similar manner.
Advantage contains 8.8% Imidacloprid and 44% Permethrin.
Imidacloprid is an excitotoxic insecticide.
Like fipronil, it works by hyperexciting the central nervous system of insects.
Their neurons fire uncontrollably resulting in muscle paralysis, organ destruction and death.
Imidacloprid is one of the most widely used pesticides in the world.
It is a chief suspect in bee colony-collapse disorder (CCD).
This leaked EPA document from November, 2010, states:
The persistence of residues and potential residual toxicity of Clothianidin in nectar and pollen suggests the possibility of chronic toxic risk to honey bee larvae and the eventual instability of the hive."
Imidacloprid is marketed as 'selectively' toxic to just insects.
But it is toxic to humans and mammals too.
The same scenario as fipronil, Bio Spot (permethrin), Revolution (selamectin), Natural Defense, and others.
Imidacloprid has never bee studied for it's excitotoxic effects on humans during long-term, low-level exposure (years of exposure to residue in air, water, food, soil and various surfaces).
Neither has it been studied for its effects on populations with varying detoxification abilities (such as due to variations in cytochrome P450 expression).
It is true that imidacloprid is 'selective' for insects and other invertebrates — it acts quickly in their systems and the destruction is easy to observe.
However, to claim that the chemical 'selectively excludes' people, mammals, and other vertebrates is wrong.
The effect is less obvious and subject to synergistic variability.
Commercially prepared formulations can be more toxic than the pure molecule by itself.
Imidacloprid (by Bayer, a proponent of thimerosal) is also commonly known under the names Admire, Gaucho, Confidor, Merit, Hachikusan, Premise, Prothor, Provado and Winner.
But don't forget about the Permethrin combined in the product.
Permethrin is a suspected endocrine disruptor and, like all pyrethroid compounds, is toxic in various ways.
Permethrin is excitotoxic, too.