pyrethroids – Lacto Bacto

The Bee and Butterfly Decline Continues

SimaJuly 20, 2026July 23, 2026Leave a comment

Haven't seen any bees or butterflies this past week. Not on flowers, not among the clover. None. All I can do is document the devastating effects of neighboring pesticide applications on pollinator populations in my organic suburban property.

A neighbor has had numerous applications by 3 services(!) for several years - on the lawn, in the garden, on plants around the house, the exterior of the house, and the hedges between properties. Basically everywhere, typically every 3 weeks. Of course, the pesticides drift to neighboring properties (mine!).

The worst for pollinators (bees, butterflies) appear to be the mosquito applications using a device that looks like a leaf blower, which is held at waist-height - these are high-volume applications. The mosquito applications are done using cypermethrin and pyrethroid insecticides (which are synthetic pesticides, e.g., made by Fendona). Pyrethroids are known to be highly toxic to pollinators such as bees and wasps, and there is growing evidence of harms to humans (here, here).

One study confirmed that pesticides are a major reason that wild bee populations are significantly down in the US. The researchers found that bee species are about 43% down in areas of heavy pesticide use. They singled out pesticides (insecticides) such as neonicotinoids and pyrethroids as drivers of this bee species reduction. They pointed out that using Integrated Pest Management (IPM) or organic methods would help reduce pesticide use and so help with bee species populations.

This means that businesses (e.g., Mosquito Joe) that apply long-lasting pyrethroids throughout suburban yards and hedges in the US are contributing directly to bee species reduction.

Other studies found that applying pesticides (no matter what kind) to lawns destroys bee populations and reduces the number of bee species. Think of lawns that are not treated with pesticides as having wildflowers, not weeds. These are bee habitats!

Some Pesticides Linked to Increased Risk of Stillbirth

SimaOctober 18, 2024Leave a comment

Once again, another study found that being exposed to pesticides has harmful health effects. Of all sorts. A recent study found that pregnant women exposed to certain pesticides increases the risk of a stillbirth. In this case, exposure means living near (less than 1/3 mile) where certain pesticides have been used.

The pesticides linked to increased stillbirths when exposed to in the pre-conception period were: cyfluthrin (a pyrethroid), zeta-cypermethrin (a pyrethroid), pyrethroids as a class, organophosphates as a class, malathion, carbaryl and propamocarb hydrochloride. Exposure in the first trimester of pregnancy to the following pesticides were associated with stillbirths: fenpropathrin (a pyrethroid), permethrin (a pyrethroid), organophosphates as a class, acephate and formetanate hydrochloride.

This means living near a non-organic farm has increased risks to pregnancy and the baby, including stillbirth. Note that some of these are also commonly used residential pesticides, such as pyrethroids (used as insecticides, and especially by mosquito and tick services). We shouldn't be surprised when pesticides applied to kill living things (e.g., insects) also have harmful effects on developing babies (also alive). [Some studies showing harmful effects of pesticides on pregnancy and the developing fetus (baby).]

From Medical Xpress: Pesticide exposure linked to stillbirth risk in new study

Living less than about one-third of a mile from pesticide use prior to conception and during early pregnancy could increase the risk of stillbirths, according to new research led by researchers at the Mel and Enid Zuckerman College of Public Health and Southwest Environmental Health Sciences Center. ...continue reading "Some Pesticides Linked to Increased Risk of Stillbirth"

Eating Organic Foods Lowers Pesticide Levels In the Body

SimaSeptember 27, 2024September 28, 2024Leave a comment

We all have some pesticide residues in our body, and the levels vary. One way that people are exposed to pesticides is from the foods they eat, specifically non-organic foods. Pesticides that people are exposed to can be measured in the blood and urine.

A recent review of 72 scientific studies found that people who eat an organic diet have lower pesticide levels in their urine. (Other pesticide exposures are from the environment around us, for example, garden and lawn pesticides.)

The study authors specifically looked at pesticide residues and metabolites of common pesticides such as organophosphates, pyrethroids, 2,4-D, and glyphosate. The most commonly mentioned pesticide residue was from pyrethroids, with 34% of studies finding it in urine. Keep in mind that only a limited number of pesticide residues were looked for. In reality, people are exposed to many more in life, including from non-organic foods that they eat.

Looking at the studies, the researchers found a massive reduction in pesticide residues when an organic diet is adopted. For example, phenol and phosphonate herbicide levels drop 41% to 100% in the studies, and pyrethroid metabolites dropped 16% to 100% [Note: each study had different drops in pesticide residues.]

And yes, you want lower levels of pesticide residues in your body for health reasons. For example, pyrethroids have been associated with numerous health harms, including cancer, endocrine disruption, and reproductive effects.

Bottom line: To lower pesticide levels in your body, eat as many organic foods as possible.

Excerpts from Beyond Pesticides: Review of Pesticide Residues In Urine, Lower Concentrations With Organic Diet

A literature review, published this month in the Journal of Agricultural and Food Chemistry, explores levels of pesticide residues found in samples of human urine with environmental exposure and dietary intake and confirms prior findings about the benefits of an organic diet. Similar to past findings, lower concentrations of chemicals are detected in the urine of participants who report eating an organic diet. ...continue reading "Eating Organic Foods Lowers Pesticide Levels In the Body"

Pesticides Are Contributing To Bee Declines

SimaSeptember 22, 2024September 22, 2024Leave a comment

For several years I've been reporting on the effects of pesticides on bees. Yes, it's all bad because pesticides kill bees. Commonly used pesticides such as pyrethroids that many view as "safe" kill bees. Pyrethroids are broad spectrum insect killers, which means they kill both beneficial bees and other pollinators, as well as potentially harmful insects (mosquitos).

A recent study confirmed that pesticides are a major reason that wild bee populations are significantly down in the US. The researchers found that bee species are about 43% down in areas of heavy pesticide use. They singled out pesticides (insecticides) such as neonicotinoids and pyrethroids as drivers of this bee species reduction. They pointed out that using Integrated Pest Management (IPM) or organic methods would help reduce pesticide use and so help with bee species populations.

This means that businesses (e.g., Mosquito Joe) that apply long-lasting pyrethroids throughout suburban yards and hedges in the US are contributing directly to bee species reduction.

From Environmental Health News (EHN): Pesticides may be contributing to the disappearance of bees across the US

A recent study published in Nature Sustainability found that pesticide use may be a major factor in the decline of bee populations within the United States. ...continue reading "Pesticides Are Contributing To Bee Declines"

Slow Death For A Pollinator

SimaSeptember 9, 2024September 11, 2024Leave a comment

There was a rare sighting of an insect pollinator in my yard recently. Unfortunately, it was dying. I suspect that pesticides were the cause of the slow death.

The ordinary person has no clue how damaging pesticide applications on their lawns and plants can be to insects living nearby. To pollinators (e.g., bees and wasps). To entire insect and bird ecosystems.

On the day I saw the dying insect pollinator, an immediate neighbor had not one, but two pesticide applications by two different services in one day! One service was for their lawn, and the second one was for mosquitos (using pyrethroid and cypermethrin insecticides) with a device that looks like a leaf blower. This device is held at waist-height (a high volume application).

Soon after that I found the dying, but still twitching, pollinator on the hood of my car (close to the property line). As I've discussed before, since the neighbor started mosquito pesticide applications 2 years ago, I rarely see a bee, wasp, or butterfly in my organic yard. At most, maybe one bee every 2 months? Before that, there were many daily.

The mosquito applications are done using cypermethrin and pyrethroid insecticides (which are synthetic pesticides, e.g., made by Fendona). Pyrethroids are known to be highly toxic to pollinators such as bees and wasps, and there is growing evidence of harms to humans (here, here).

Of course, when pesticides are applied, they drift and travel to non-target neighboring areas. It's sad. But totally legal.

Where Are the Hummingbirds?

SimaJuly 25, 2024July 26, 2024Leave a comment

Hummingbirds like the red Cardinal flower (also called lobelia). Really like them. Butterflies also swarm to these flowers. Usually.

But not always. Since an immediate neighbor started using a mosquito service that uses high-volume pesticide applications of a synthetic pyrethroid (think of a leaf blower on steroids), there has been an absence of butterflies, bees, and hummingbirds in my garden. Other people also report this happening.

Even though the synthetic pyrethroids (e.g., Fendona) are not neonicotinoids, which we know kills bees - pyrethroids are also toxic to bees. Pyrethroids are broad-spectrum insecticides - that is, they kill a wide variety of insects indiscriminately. This totally destroys the biodiversity of species in the environment. We need bees, butterflies, hummingbirds, and other species!

But what are the pesticides doing to humans? Developing children? The developing fetus? Sick people? Everyone? Yes, there is accumulating evidence of health harms to humans, especially children and babies.

Buyer Beware When It Comes to “Organic-Based” Lawn Care Services

SimaOctober 2, 2023October 2, 2023Leave a comment

Buyer beware when it comes to lawn care services. Lately I've been seeing a number of lawn care companies saying they offer "organic-based" or "organic weed-free lawn care" or "natural lawn care". Nope, nope, nope.

These companies do NOT provide organic lawn care. Instead it's the same old routine of using toxic pesticides disguised with organic, environmentally friendly buzzwords. And yes, these pesticides are harmful to adults, children, pets, wildlife, birds, bees, butterflies, and the environment.

How do you you know that they are not providing organic lawn care?

1) One big tip off is "weed free" lawns. Nope. A real organic lawn has diversity of plants - for example, clover. Only toxic pesticides can give you the sterile carpet look. Yes, an organic lawn can be lush, beautiful, and green, but it's different than a sterile carpet with only 1 species of grass (a monoculture).

2) Another warning sign is that they routinely apply "preemergent herbicides" (weed-killers). Nope, nope, nope. For example, one popular herbicide used by such companies is 2,4,-D. This was one of the 2 pesticides used in Agent Orange, and yes - it sticks around. Yikes!

3) They use the word "organic-based". They generally use this only when discussing fertilizers. Hah! Talk is cheap. I haven't yet seen evidence of real organic fertilizers being used.

4) They will routinely schedule "insect control" - of course, by using toxic pesticides. If they were real organic, they wouldn't do that - it wouldn't be needed and/or desired.

By the way, pyrethroids are synthetic toxic pesticides - they are NOT from chrysanthemums and have different effects, such as being toxic to bees and butterflies, and with harmful effects on humans, especially children. They are not used in real organic lawn care. ...continue reading "Buyer Beware When It Comes to “Organic-Based” Lawn Care Services"

Looking For Bees

SimaAugust 2, 2023July 21, 2024Leave a comment

Ever since an immediate neighbor started using a mosquito and tick service last year, it is rare to find bees or butterflies in my organic yard and garden. Where I formerly had multitudes of bees, I now rarely see one.

This is because mosquito/tick services use pesticides that are highly toxic to bees and butterflies. The applicators hold pesticide sprayers at waist height that spray insecticides directly out at high volume, and usually walk along a property 's perimeter spraying.

Typically pyrethroid and cypermethrin insecticides (e.g. made by Fendona) are used. These are broad-spectrum (kill many species, including bees), microencapsulated, long-lasting (up to 90 days), and applications are every 3 weeks.

Yup, I observed the applicator walking along the neighbor's yard perimeter applying the insecticides at waist height directly into my hedges (it is obvious to the applicator that they are on my property). As he walked along, I could see the hedges violently shaking from the high volume application.

That is a deliberate non-target application of pesticides, which is against the law in my state. But it's what these companies do with impunity - go look at their web-site photos. By the way, pesticide contamination of adjacent properties will always be a problem in suburban yards with this kind of application.

Bees are pollinators, and unfortunately they are in serious decline in the United States. Pesticides are a big cause. Pesticides, including pyrethroids, also have numerous health effects on humans - none of them good. Especially worrisome is exposure during pregnancy or in young children.

A rare bee sighting among the oregano blossoms.

Pyrethroids and Autism Spectrum Disorder

SimaApril 28, 2023April 28, 2023Leave a comment

A recent study may contribute to explaining why autism spectrum disorder (ASD) rates are rising so rapidly in the US. The CDC reports that 1 in 36 children have autism spectrum disorder as of 2020!! Researchers and physicians agree that things in the environment (e.g., pesticides) are playing a role in this increase.

Even though the study was conducted in mice, it examined the impact of pesticides called pyrethroids on neurological development. They found that even at low levels that humans are typically exposed to, there were neurological effects on mice who were exposed during pregnancy. Their behaviors were altered in a negative way, for example an increase in repetitive behaviors.

Pyrethroids are being used in increasing amounts in the US for all sorts of insect treatments, both inside and outside of homes. It's very frequently used against mosquitos. Studies find that 70 to 80% of the US population have pyrethroid breakdown products (metabolites) in the blood. This is because we are exposed to chronic low levels - whether in the air, in water, around our homes or workplace.

The researchers wrote in the published research that scientists are especially concerned with pyrethroid exposure because it has a harmful effect on fetal development in both humans and animals. Studies are finding links from pyrethroid exposure during pregnancy or infancy and developmental delays.

"Critically, evidence from recent epidemiology and longitudinal studies suggests that ambient prenatal exposure to pyrethroid pesticides poses a risk for autism, developmental delay, and neurodevelopmental disorders in general. Analysis of data from the CHARGE study showed a significant increase in risk for either ASD or developmental delay from exposure during pregnancy to pyrethroid pesticides being applied up to 1.5 km from the home. A regional study in New York showed an association between areas where aerial application of pyrethroid pesticides was used, and ASD and developmental delay prevalence in the area. Additionally, the presence of pyrethroid metabolites in blood or urine correlates with risk for ADHD in children."

Bottom line: Avoid using pyrethroids around the home and yard. Look into IPM (Integrated Pest Management) or organic and natural ways to deal with pests. Pyrethroids are also toxic to bees, and we need bees. Synthetic pyrethroids (which is what is commonly used) are not like natural extracts from the chrysanthemum flower, and don't let someone tell you they are.

Excerpts from Medical Xpress: Research links common insecticide to neurodevelopmental disorders

A new study from The University of Toledo suggests early exposure to a common class of insecticides called pyrethroids may increase the risk of autism and other developmental disorders, even at levels currently recognized as safe by federal regulators. ...continue reading "Pyrethroids and Autism Spectrum Disorder"

Common Pesticides and Behavioral Problems in Children

SimaMarch 16, 2017October 27, 2017Leave a comment

Another study has linked childhood behavioral problems to pesticide exposure, this time to pyrethroid insecticide exposure. Pyrethroids are synthetic pesticides (insecticides) that are increasingly used for personal use (mosquito repellents and treatments for head lice, scabies), on pets (for fleas), home use (e.g., Raid pesticides), and in agriculture.

Until recently, they have been viewed as "safer" and posing fewer risks to human health than older pesticides, but a growing body of research is finding that pyrethroid pesticides share similar neurocognitive health effects as older pesticides. Neurocognitive refers to the neural processes of the brain and central nervous system involved in cognitive functioning. Pyrethroids get into people various ways: through inhalation, absorbed through the skin, and ingested in food. And yes, they cross the placenta (they have been detected in the placental cord immediately after birth).

In this study, researchers looked at levels of pyrethroid metabolites (the breakdown products from pyrethroids) in the mother's urine during early pregnancy and in the child's urine when the child was 6 years of age. They looked at how social a child is (altruism), whether the child is inhibited and has difficulty sharing problems or asking for help (internalizing behaviors), as well as how defiant or disruptive a child is (externalizing behaviors, which can include hyperactivity and oppositionality).

Pyrethroids (the metabolites) were regularly detected in both mothers and children participating in the study. Internalizing disorders were associated with high levels of one pyrethroid metabolite (cis-DCCA, a breakdown product of permethrin, cypermethrin, and clyfluthrin) in pregnant mothers’ urine. Childhood exposure to pyrethroids (as measured in the child's urine) was linked to externalizing disorders. Researchers hypothesized that the behavioral difficulties were due to changes in the child’s brain. The authors stated: “The current study suggests that exposure to certain pyrethroids at the low environmental doses encountered by the general public may be associated with behavioural disorders in children.” "Internalizing behaviors are inhibited and overcontrolled in nature, while children with

Other studies have also found negative health effects on children from pyrethroids - for example, an association between synthetic pyrethroid exposure and ADHD hyperactivity and impulsivity. Recent research found that living near a farm field where pyrethroids are applied during a mother’s third trimester or just before conception corresponds with a greatly increased risk of having a child with autism spectrum disorder.

What can one do? Main one: try to avoid using and ingesting (in food) synthetic pyrethroids. This means avoid routine "pesticide treatments" of your home and garden, and instead use least-toxic methods to control pests around the home and garden (such as baits for insects, caulk holes, etc.). Try viewing weeds in the lawn as native wildflowers and the flowers as bee habitats (yes, you'll also be saving bees!). Eat as many organic foods (especially fruits and vegetables) as possible - this will lower the amount of pesticides in your body. This is because synthetic pyrethroids are not allowed in organic farming. The good news is that pyrethroid pesticides leave the body within days, so with some lifestyle changes you can really lower your pesticide levels.

From Medscape: 'Safe' Insecticides Tied to Neurobehavioral Problems in Kids

Prenatal and childhood exposure to pyrethroid insecticides may adversely affect neurobehavioral development in children up to age 6 years, new research shows. A group of French researchers led by Jean-François Viel, MD, PhD, and Prof Andreas G. Franke, MD, both of the University of Mainz, Germany, investigated the associations between exposure to pyrethroid insecticides and behavioral skills in 6-year-olds.

Using a longitudinal design, the researchers assessed pyrethroid exposure in children prenatally and at age 6 years. They found that in 6-year-old children, increased prenatal concentrations of the cis-dimethylcyclopropane carbolic acid metabolite were associated with internalizing difficulties. A positive association was also found between the presence of childhood 3-phenoxybenzoic acid (3-PBA) and externalizing difficulties.

The researchers used a longitudinal design to assess the relationship between prenatal and childhood pyrethroid concentrations, using data from the French PELAGIE mother-child study. That study enrolled 3421 pregnant women from Brittany, France, between 2002 and 2006. Of this cohort, 287 randomly selected mothers agreed to participate in neuropsychological follow-up. Psychologists who were blinded to pyrethroid exposure levels in the study participants conducted neurodevelopmental assessments and maternal interviews to assess the home environment. They also collected children's urine samples as well as dust samples.