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New research published in The Lancet estimates that lead exposure results in about 400,000 deaths every year in the USA - which includes about 250,000 deaths from cardiovascular disease. The study looked at "historical exposure" to lead, which means they looked at a person's lead exposure years ago (which could have been from many sources, such as breathing lead contaminated dust, drinking water from leaded pipes, from lead paint, leaded gas, or eating from cans that have been soldered with lead). What was noteworthy in this study following over 14,000 adults was that there were increased death rates even from low lead blood levels (concentrations of lead in blood lower than 5 μg/dL).

Lead exposure has been declining since the 1970s after lead was eliminated (banned) from paint and gasoline, but this study looked at adults born in the years when lead exposure was higher during childhood and adulthood. Baseline data (blood lead levels) was collected between 1988 and 1994 and then individuals were followed for the next 2 decades. The researchers found that there was a dose response curve - the higher the blood lead level, the higher the death rate from any cause (all-cause mortality), from cardiovascular disease, and from ischaemic heart disease in the next two decades.

Lead is a naturally occurring heavy metal, but it's also a poisonous substance for humans, and accumulates in teeth and bones. Lead can pass through the blood-brain barrier in children and fetuses and kill brain cells (and cause neurological damage). Lead can enter blood vessels and harm the endothelial cells that line the blood vessels. This process hardens arteries and causes plaque to form in blood vessels, increasing blood pressure, and the risk of heart disease and stroke. Lead can damage the kidneys, which play an important role in regulating blood pressure, and so increase a person’s risk of heart disease and stroke.

The Centers for Disease Control and Prevention (CDC) have stated that there are no safe blood levels of lead for children (zero is best), and the researchers of this study believe the same is true for adults. From Science Daily:

Historical lead exposure may be linked to 256,000 premature deaths from cardiovascular disease in adults in United States each year

New estimates suggest that 256,000 premature deaths from cardiovascular disease -- including 185,000 deaths from ischemic heart disease -- in the USA may be linked to historical lead exposure in middle-aged and older adults (people currently aged 44 years or over), according to an observational study following 14,300 people for almost 20 years, published in The Lancet Public Health journal.  ...continue reading "Even Low Level Lead Exposure Is Linked to Later Health Problems"

The researchers of a recent study caution about the regular use of lavender and tea tree essential oils (e.g. in lotions or soaps) - that the oils may act as endocrine disruptors (chemicals that disrupt hormones and their actions in the body). Earlier research found a link between regular use of lavender essential oil and tea tree oil and abnormal breast growth in boys - called prepubertal gynecomastia. The condition went away after they stopped using the products.

Now researchers examined 8 common chemical components of lavender and tea tree oils for endocrine disrupting activity in lab tests - and yes, they found varying degrees of endocrine-disrupting activity in the chemicals. The researchers (from the National Institute of Environmental Health Sciences or NIEHS) warn that endocrine disrupting chemicals found in these 2 essential oils are also found in 65 other essential oils.

Note that essential oils are widely available, but they are not regulated by the FDA. Bottom line: No matter the age, avoid prolonged use of lavender and tea tree oil in personal care products, including "aromatherapy" -  especially important for children and pregnant women. The results were presented today at the 100th annual meeting of the Endocrine Society (ENDO) in Chicago. From Science Daily:

Chemicals in lavender and tea tree oil appear to be hormone disruptors

A new study lends further evidence to a suspected link between abnormal breast growth in young boys -- called prepubertal gynecomastia -- and regular exposure to lavender or tea tree oil, by finding that key chemicals in these common plant-derived oils act as endocrine-disrupting chemicalsLavender and tea tree oil are among the so-called essential oils that have become popular in the United States as alternatives for medical treatment, personal hygiene and cleaning products, and aromatherapy. Various consumer products contain lavender and tea tree oil, including some soaps, lotions, shampoos, hair-styling products, cologne and laundry detergents.   ...continue reading "Are Some Essential Oils Endocrine Disruptors?"

As many (most?) people know nowadays - drinking alcohol during pregnancy can have negative effects on the developing baby. Drinking a lot of alcohol can result in fetal alcohol syndrome, but drinking smaller amounts (frequently or binge drinking now and then) can also have negative effects, even though not as severe. The effects from alcohol are called fetal alcohol spectrum disorders - because the effects are along the spectrum from major to minor effects. Currently they're called  fetal alcohol syndrome, partial fetal alcohol syndrome, or alcohol related neurodevelopmental disorder. Effects are generally determined by the child's facial features, physical growth, neurobehavioral development, and prenatal alcohol exposure (esp. by interviewing the mother).

A recent study tried to determine how common are fetal alcohol spectrum disorders in the United States. The researchers screened 6639 first grade children in 4 communities from different areas of the US, and fully evaluated about 3000 children for fetal alcohol spectrum disorders. They found that the disorders ranged from 1.1% to 5% in the communities studied - and they felt that this is a conservative estimate. Interestingly, almost all of these newly diagnosed children had not been diagnosed with fetal alcohol spectrum disorders before the study. So it's easy to miss, and to misdiagnose- thus a "hidden problem".

How to avoid this problem? Don't drink alcohol during pregnancy. But unfortunately many women don't realize that they are pregnant in the first trimester, especially if the pregnancy is unplanned. The Centers for Disease Control (CDC) says on its site (official advice) that women should: "Stop drinking alcohol if they are trying to get pregnant or could get pregnant." What about men who drink alcohol and then conceive a child? There is also some research (mainly animal research) that alcohol can have negative effects on the father's sperm and the resulting fetus. Not fetal alcohol spectrum disorders, but perhaps other health effects which are still being determined.

From  journalist Pam Belluck's article at the NY Times: Far More U.S. Children Than Previously Thought May Have Fetal Alcohol Disorders

More American children than previously thought may be suffering from neurological damage because their mothers drank alcohol during pregnancy, according to a new study. The study, published Tuesday in the journal JAMA, estimates that fetal alcohol syndrome and other alcohol-related disorders among American children are at least as common as autism. The disorders can cause cognitive, behavioral and physical problems that hurt children’s development and learning ability.

The researchers evaluated about 3,000 children in schools in four communities across the United States and interviewed many of their mothers. Based on their findings, they estimated conservatively that fetal alcohol spectrum disorders affect 1.1 to 5 percent of children in the country, up to five times previous estimates. About 1.5 percent of children are currently diagnosed with autism.

The range of fetal alcohol spectrum disorders (also called FASDs) can cause cognitive, behavioral and physical difficulties. The most severe is fetal alcohol syndrome, in which children have smaller-than-typical heads and bodies, as well as eyes unusually short in width, thin upper lips, and smoother-than-usual skin between the nose and mouth, Dr. Chambers said. A moderate form is partial fetal alcohol syndrome. Less severe is alcohol-related neurodevelopmental disorder, in which children have neurological but not physical characteristics and it is known that their mothers drank during pregnancy.

Then there is the stigma that often makes mothers reluctant to acknowledge alcohol consumption. “When you identify a kid with FASD, you’ve just identified a mom who drank during pregnancy and harmed her child,” said Susan Astley, director of the Fetal Alcohol Syndrome Diagnostic and Prevention Network at the University of Washington, who was not involved in the study. While Dr. Astley, a longtime expert in the field, said she admired the researchers’ hard work, she said the reliability of the study’s numbers was hampered by several factors. For example, only 60 percent of eligible families in the schools allowed their children to be evaluated and more than a third of those children’s mothers declined to answer questions about drinking during pregnancy.

The authors of the study, which was funded by the National Institute on Alcohol Abuse and Alcoholism, acknowledged the study’s limitations and tried to partly compensate by providing a conservative estimate (of 1.1 percent to 5 percent) that is likely low and another estimate (of 3.1 percent to 9.9 percent) that is likely high. Dr. Chambers also said the results might not generalize across the country because although the four communities were diverse, they did not include a large, high-poverty urban area or certain rural or indigenous communities that struggle with high rates of alcoholism. The locations, which are not named in the publication, include small-to-midsize cities in the Midwest and Rocky Mountains, a Southeast county and a Pacific Coast city the authors identified in interviews as San Diego. [Original study.]

Another large study found problems with parents spanking children - specifically that spanking may make a child's behavior worse over time. More than 50 countries ban spanking, but many parents still spank in the US (and yes, it is legal). Unfortunately some states in the US also allow spanking (corporal punishment) in schools even today, which is viewed by many as physical abuse.

Psychologists at the University of Texas at Austin and the University of Virginia found that children who were spanked by their parents at age five years were more likely to have behavioral problems between the ages 6 and 8. "Our findings suggest that spanking is not an effective technique and actually makes children's behavior worse not better," says lead author Elizabeth T Gershoff.

The researchers had 2 main conclusions. First:They found no evidence that spankings in general or recent spankings are effective at reducing "externalizing behavior problems" (e.g., fighting, arguing, getting angry, disrupting activities, being impulsive - as reported by their teachers) over time.  Instead, this study (like others) found that instead spanking children predicts more behavior problems in the future in children. And secondly, while the number of spankings was important (frequent vs not frequent spankings) with the result that children receiving frequent spankings had more behavior problems later, they also found  that a child who is spanked even once is more likely to have behavior problems in the future than a similar child who is never spanked. From Medical Xpress:

Spanking linked to increase in children's behavior problems

Children who have been spanked by their parents by age 5 show an increase in behavior problems at age 6 and age 8 relative to children who have never been spanked, according to new findings in Psychological Science, a journal of the Association for Psychological Science. The study, which uses a statistical technique to approximate random assignment, indicates that this increase in behavior problems cannot be attributed to various characteristics of the child, the parents, or the home environment - rather, it seems to be the specific result of spanking.

Gershoff and coauthors Kierra M. P. Sattler (University of Texas at Austin) and Arya Ansari (University of Virginia) examined data from 12,112 children who participated in the nationally representative Early Childhood Longitudinal Study. When the children were 5 years old, their parents reported how many times they had spanked their child in the past week (if any). The researchers classified any child whose parent provided a number other than zero as having been spanked.

The researchers then matched children who had been spanked with those who hadn't according to 38 child- and family-related characteristics, including: the child's age, gender, overall health, and behavior problems at age 5; the parent's education, age... Pairing the children in this way yielded two groups of children whose main difference was whether their parents had spanked them, effectively accounting for other factors that could plausibly influence the behavior of both parent and child. This approach allowed the researchers to approximate the random assignment of participants to groups, a hallmark of experimental design.

To gauge children's behavior problems over time, Gershoff, Sattler, and Ansari examined teachers' ratings when the children were 5, 6, and 8 years old. Children's teachers reported the frequency with which the children argued, fought, got angry, acted impulsively, and disturbed ongoing activities. The results were clear: Children who had been spanked at age 5 showed greater increases in behavior problems by age 6 and also by age 8 when compared with children who had never been spanked.

Gershoff and colleagues conducted a similar analysis with only those children who had been spanked by their parents, comparing children who had been spanked in the week before the study (which suggests frequent spanking) and those who had not. Children spanked in the past week at age 5 also experienced greater increases in problem behavior at age 6 and 8 compared with children not spanked as frequently.

The following study was done in England, but the results should be taken seriously and may (probably) apply to the US also - painted and enameled glassware ("externally decorated glassware") may contain high levels of lead and cadmium. The researchers found that more than 70% of the products (52 out of 72) tested positive for lead, and the metal was found in all colors, including the decorated gold leaf of some items. A similar number (51 out of 72) tested positive for cadmium, with the highest concentrations usually encountered in red enamel.

They found this in products manufactured both in Europe and China - which is why I think the results apply to painted or decorated glassware in the USA also. It probably also applies to some (many?) painted ceramics. So beware!  If you use painted or enameled glassware, you are at increased risk for ingesting lead and cadmium, both of which are linked to health problems - especially for developing fetuses and children. The best safe level of each is zero. The researchers mention that there are newer alternatives that are safe (lead and cadmium free). From Science Daily:

Drinking glasses can contain potentially harmful levels of lead and cadmium

Enameled drinking glasses and popular merchandise can contain potentially toxic levels of lead and cadmium, a study has shown. Researchers at the University of Plymouth carried out 197 tests on 72 new and second-hand drinking glass products, including tumblers, beer and wine glasses, and jars.

They found lead present in 139 cases and cadmium in 134, both on the surface of the glasses and, in some cases, on the rims, with concentrations of lead sometimes more than 1000 times higher than the limit level. Tests showed that flakes of paint often came away from the glass under when simulating sustained use, indicating the substances could be ingested over a prolonged period.

The study, published in Science of the Total Environment, analysed a range of glassware using portable x-ray fluorescence (XRF) spectrometryMore than 70% of the products (52 out of 72) tested positive for lead, and the metal was found in all recorded colours, including the decorated gold leaf of some items. A similar number (51 out of 72) tested positive for cadmium, with the highest concentrations usually encountered in red enamel.

The lead concentrations ranged from about 40 to 400,000 parts per million (ppm), while quantities of cadmium ranged from about 300 to 70,000 ppm. According to the US Office of Environmental Health Hazard Assessment, the limit levels for the externally decorated lip area of drinking glass are 200 ppm and 800 ppm respectively.

In the research, Dr Turner highlights that the Federation of European Screen Printers Associations says organic inks are becoming more popular than metallic pigments because of environmental concerns, and that such inks were evident on a number of newly-purchased products which proved negative for lead and cadmium.

He also says that additional analyses confirmed that hazardous elements are also used to decorate a wider range of consumer glassware that has the potential to be in contact with food, including the exteriors of bottles for the storage of beer, wine or spirits, the external text and logos on egg cups, jugs and measuring cups, and the undersides of coasters and chopping boards. "Given that safer alternatives are available to the industry, the overall results of this study are both surprising and concerning," Dr Turner added. "Why are harmful or restricted elements still being employed so commonly to decorate contemporary glassware manufactured in China, the European Union and elsewhere? " [Original study.]

A while ago I posted the results of studies showing differences in infant  microbiomes (community of microbes) depending on whether the babies were delivered vaginally or by C-section, and also that "vaginal seeding" may eliminate some of these differences. [C-section babies also have a higher incidence of some health issues, such as allergies, asthma, etc.] Well....that research generated a lot of controversy both for and against, and resulted in many women requesting that "vaginal seeding" be done to their babies after they were delivered by C-section. Even the noted microbiome researcher Rob Knight publicly admitted that the procedure was done to his baby after his partner received a C-section.

Vaginal seeding is the process of swabbing the bodies of C-section babies (including the mouth and nose) with a gauze pad containing the vaginal fluids from their mothers in the minutes after birth - so that the baby is exposed to the same maternal microbes as a baby born vaginally (because mothers transmit microbes to the baby as it moves through the birth canal). Initial research showed this made the microbiomes of the C-section babies look a lot like vaginally born babies, especially their skin and oral microbiomes, but whether these differences persist after a few months is unclear.

Now the American College of Obstetrics and Gynecology (ACOG) has come out with a position paper that vaginal seeding should not be done to babies, except as part of an official clinical trial. Their main opposition to the procedure is fear of transmitting pathogenic bacteria or viruses (e.g. group B streptococci, and STDs). The main reasons in support of doing the  vaginal seeding procedure is the body of research finding differences among C-section and vaginally delivered babies (allergies, asthma, etc.), and the concern that at least some of this may be due to lack of  exposure to maternal vaginal microbes during delivery. Instead, ACOG suggests breastfeeding the baby to transmit maternal microbes to the baby to "seed the gut". And if "a patient insists on performing the procedure herself, ACOG recommends ob-gyns have a documented discussion of the potential risks".

As can be expected, there is an outcry and rejection by some (many?) of the ACOG position paper. At least the ACOG paper acknowledges that every woman can make her own decision regarding this issue, even though they may not support it. And absolutely everyone agrees that more research is needed. From Ars Technica:

Doctors warn new parents: Step away from the vaginal fluid swabs

To slather, or not to slather—that is the question that has been roiling doctors, scientists, and new parents recently. And a new ruling by a doctor’s group stands to muck up the debate further. Amid the birth of microbiome research, some scientists have advocated for smearing bacteria-laden vaginal secretions on any newborns who missed out—namely those born via Caesarian section. Scientists keenly hypothesize that such a gooey glaze can “seed” a more-or-less sterile infant with life-long microbial companions. These wee chums may help train an infant's immune system and dodge issues like allergies and asthma later in life. Several studies have indeed found correlations between C-section deliveries and higher risks of those conditions.

In the latest turn to the controversy, the American College of Obstetricians and Gynecologists’ (ACOG) Committee on Obstetric Practice issued a November opinion firmly wiping up the slimy idea. In its opinion, the committee said it: “…does not recommend or encourage vaginal seeding outside of the context of an institutional review board-approved research protocol, and it is recommended that vaginal seeding otherwise not be performed until adequate data regarding the safety and benefit of the process become available.”

The few studies we do have on infant microbiomes provide no clear answers on the significance of an early “seeding” for health. A 2016 review looking at the patterns of microbial communities in the guts of infants in their first year found that C-section babies did show differences in the first three months. However, those differences disappeared by six months. Similarly, a small study of 18 babies also published last year found that vaginal seeding could eliminate microbial differences between vaginally and C-section delivered babies. But the study only looked at the infants' microbiomes in that first month, and the health effects—if any—are unknown.

The most concerning thing about vaginal seeding, the committee argues, is the potential for transmitting pathogens, such as herpes simplex virus, human papilloma virus (HPV), group B streptococci, and Neisseria gonorrhea. .... If a woman insists on the seeding, the committee recommended she be thoroughly tested and informed of the risks—as well as discouraged.

The prestigious medical journal The Lancet recently released a report by its Commission On Pollution and Health on the effects of various types of pollution (water, air, occupational, chemical, etc) on people and world economies - that is, the effect of pollution on "global health". The main finding: Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16 percent of all deaths worldwide. Pollution is now known to cause a wide variety of diseases and health problems, including asthma, cancer, neurodevelopmental disorders, and birth defects in children; and heart disease, stroke, chronic obstructive pulmonary disease, and cancer in adults. The list of health effects keeps increasing. [See all posts on pollution.]

The report states that certain types of pollution are increasing throughout the world - air, chemical, and soil pollution.They also discuss new and emerging pollutants (most of them chemical pollutants) whose effects on human health
are not yet fully understood, yet they are widely found in the environment and detected in most humans. The authors of the report even say: "At least some of these chemical pollutants appear to have potential to cause global epidemics of disease, disability, and death."

Chemical pollutants include: developmental neurotoxicants (e.g. pesticides, lead, mercury), endocrine disruptors (which have reproductive effects and can alter fertility), new classes of pesticides such as the neonicotinoids, chemical herbicides such as glyphosate (found in Roundup and the most commonly used pesticide in the world), nano-particles, and pharmaceutical wastes.

While most deaths from all sorts of pollution are currently occurring in poorer developing countries (e.g. China and India), we in the United States also have health effects and deaths from pollution - just not on the scale of those countries. Also, remember that winds carry pollutants globally - so that air pollution in China will cross the Pacific Ocean on the winds to the US.

Everyone agrees that taking action works - think of the success in banning lead, asbestos, and DDT in the United States. And amounts of six common air pollutants have been reduced by about 70% since passage of the Clean Air Act in 1970. We can thank laws, and organizations established due to environmental problems and crises in the past (e.g. the Environmental Protection Agency (EPA), Superfund legislation, Clean Water Act, Clean Air Act) for that.

From Science Daily: Pollution responsible for 16 percent of early deaths globally

Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16 percent of all deaths worldwide, according to a report. Simon Fraser University health sciences professor Bruce Lanphear is a Commissioner and author of The Lancet Commission on Pollution and Health that has released a report detailing the adverse effects of pollution on global health. ...."Pollution, which is at the root of many diseases and disorders that plague humankind, is entirely preventable." 

Commission findings include: - Pollution causes 16% of all deaths globally. Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16% of all deaths worldwide -- three times more deaths than AIDS, tuberculosis, and malaria combined; and fifteen times more than all wars and other forms of violence. It kills more people than smoking, hunger and natural disasters. In some countries, it accounts for one in four deaths. - Pollution disproportionately kills the poor and the vulnerable. Nearly 92% of pollution-related deaths occur in low- and middle-income countries. Within countries, pollution's toll is greatest in poor and marginalized communities. Children face the highest risks because small exposures to chemicals in utero and in early childhood can result in lifelong disease and, disability, premature death, as well as reduced learning and earning potential. - Pollution is closely tied to climate change and biodiversity. Fossil fuel combustion in higher-income countries and the burning of biomass in lower-income countries accounts for 85% of airborne particulate pollution. Major emitters of carbon dioxide are coal-fired power plants, chemical producers, mining operations, and vehicles.

A few excerpts (lead & pesticides) from the report in The Lancet: The Lancet Commission on pollution and health

Another example of the economic benefits of addressing pollution is seen in the consequences of removing lead from gasoline in the USA. This intervention began in 1975 and, within a decade, had reduced the mean blood concentration of lead in the population by more than 90%, almost eliminated childhood lead poisoning, and increased the cognitive capacity of all American children born since 1980 by 2–5 IQ points. This gain in intelligence has increased national economic productivity and will yield an economic benefit of US$200 billion (range $110 billion–300 billion) over the lifetimes of each annual cohort of children born since 1980, an aggregate benefit to-date of over $6 trillion.

Developmental neurotoxicants: Evidence is strong that widely used chemicals and pesticides have been responsible for injury to the brains of millions of children and have resulted in a global pandemic of neurodevelopmental toxicity. The manifestations of exposure to these chemicals during early development include loss of cognition, shortening of attention span, impairment of executive function, behavioural disorders, increased prevalence of attention deficit and hyperactivity disorder, learning disabilities, dyslexia, and autism.

Pesticides: More than 20,000 commercial pesticide products, including insecticides, herbicides, fungicides, and rodenticides are available on world markets. More than 1.1 billion pounds of these products are used in the USA each year and an estimated 5.2 billion pounds globally. ....The organophosphate insecticides are a large and widely used class of pesticides. Members of this class of chemicals are powerful developmental neurotoxicantsand prenatal exposures are associated with persistent deleterious effects on children’s cognitive and behavioural function and with long-term, potentially irreversible, changes to brain structure that are evident on MRI. 

Chemical herbicides account for nearly 40% of global pesticide use and applications are increasing. A major use is in production of genetically modified food crops engineered to be resistant to glyphosate (Roundup), the world’s most widely used herbicide. Glyphosate-resistant, so-called “Roundup Ready” crops, now account for more than 90% of all corn and soybeans planted in the USA, and their use is growing globally. Glyphosate is widely detected in air and water in agricultural areas, and glyphosate residues are detected in commonly consumed foods.

For years studies have suggested that eating blueberries and other berries is good for our health (here, here, and here). Now another study suggests that eating wild blueberries benefits children's thinking, specifically attention and "executive function" (mental processes which lets people plan, organize, and complete tasks). What was nice in this study was that it was "double-blind"- which meant that biases couldn't influence the results. 

Flavonoids are a diverse group of phytonutrients (plant chemicals) found in almost all fruits and vegetables. They are powerful antioxidants with anti-inflammatory and immune system benefits. And yes, other studies have also found various benefits to mental processes with an increase of flavonoids in the diet - in both children and adults.

What foods contain flavonoids? There are 6 main classes of flavonoids, and each is found in different foods: - Anthocyanidins – found in red, purple,and blue berries, red wine, and red and purple grapes. - Flavonols - found in onions, leeks, broccoli, Brussels sprouts, kale, tea, berries, beans, and apples. - Flavones - found in parsley, celery, and hot peppers. - Isoflavones - found in soybeans, soy products, and legumes. - Flavanones - found in citrus fruit and tomatoes. - Flavanols - found in tea, red wine, grapes, apples, fava beans, and cocoa. From Medical Xpress:

Primary school children could show better attention by consuming flavonoid-rich blueberries, following a study conducted by the University of Reading. In a paper published in Food & Function, a group of 7-10 year olds who consumed a drink containing wild blueberries or a matched placebo and were tested on their speed and accuracy in completing an executive task function on a computer.The double blind trial found that the children who consumed the flavonoid-rich blueberry drink had 9% quicker reaction times on the test without any sacrifice of accuracy. In particular, the effect was more noticeable as the tests got harder.

Previous [Univ. of] Reading research has shown that consuming wild blueberries can improve mood in children and young people, simple memory recall in primary school children, and that other flavonoid rich drinks such as orange juice, can also improve memory and concentration.

Wild blueberries are grown and harvested in North America, and are smaller than regular blueberries, and are higher in flavonoids compared to regular varieties. The double-blind trial used a flavonoid-rich wild blueberry drink, with a matched placebo contained 8.9 g of fructose, 7.99 g of glucose and 4 mg of vitamin C matching the levels of nutrients found in the blueberry drink. [Original study.] 

Once again a study finds that pesticide exposure is linked to an adverse health effect - that pesticide exposure in the home during pregnancy and early childhood is linked to an elevated risk of brain tumor in the child. Other studies have also found that pesticides used in the home are associated with a higher risk of childhood cancers.

This is because pesticides do cross the placental barrier, as the study researchers point out: "There is evidence that pesticides cross the fetal-placental barrier since residues of some insecticides have been found in umbilical cord blood, neonatal hair, and meconium following maternal exposure during pregnancy." Also, the International Agency for Research on Cancer (IARC) has classified "more than twenty pesticide chemical compounds as potential human carcinogens".

The following are examples (but there are more) of other studies finding pesticide and childhood cancer links: A meta-analysis published in 2015 in Pediatrics by researchers at Harvard University found that children exposed to indoor insecticides (also herbicides) have a higher risk of certain childhood cancers, specifically leukemia, lymphomas, and brain tumors. A 2013 study published in Cancer Causes and Control found that professional pest control applications in the home within a year of conception and during pregnancy was associated with a higher risk of childhood brain tumors. A review of studies published in 2010 found that pesticide exposure during pregnancy and childhood increased the risk of childhood leukemia.

The good news is that there are alternatives to exposing fetuses and children to toxic pesticides at home - by using alternative ways of dealing with pests, such as least toxic Integrated Pest Management (IPM) or organic methods. That means doing other things (such as sealing or caulking holes, putting out traps and baits, vacuuming), a focus on least toxic methods and on prevention (here and here), rather than routinely applying toxic pesticides. If needed, least toxic pesticides include boric acid and vinegar. Other sources of pesticide exposure for pregnant women and children are foods and exposure in settings outside the home - perhaps even a friend's yard. By the way, pesticide exposure for everyone is linked to a higher risk of health problems, not just pregnant women and children.

From Science Daily: Pesticide use during pregnancy linked to increased risk of childhood brain tumors

Previous epidemiological studies have suggested that exposure to pesticides during pregnancy may have a possible role in the development of childhood brain tumors. In a new International Journal of Cancer analysis, researchers found a link between maternal residential pesticide use -- particularly insecticides -- and the risk of childhood brain tumorsThe analysis included 437 malignant childhood brain tumor cases and 3102 controls from two French studies. Pesticide use was associated with a 1.4-times increased risk of childhood brain tumors.

The investigators noted that many pesticide compounds are classified as probable carcinogens, and there is evidence that some insecticides can pass through the feto-placental barrier. "Although such retrospective studies cannot identify specific chemicals used or quantify the exposure, our findings add another reason to advise mothers to limit their exposure to pesticides around the time of pregnancy," said Nicolas Vidart d'Egurbide Bagazgoïtia, lead author of the study. [Original study.]

Two recent studies, both done in California, looked at different aspects of pesticide exposure. They highlight how people can be exposed to pesticides in the air they breathe, especially if they live in areas where pesticides are heavily applied (such as farms). But keep in mind that even in suburbia, every time a neighbor applies pesticides on the lawn or trees - there is drift, and so you are also exposed (e.g., breathing it, droplets on the skin).

The first study found that pregnant women with high pesticide exposure (living in areas near farms using pesticides) had increases in adverse birth outcomes (low birth weight, shorter pregnancy length, preterm birth, birth defects or abnormalities). No effects were seen with low pesticide exposure. But note that these results are what could be seen at birth - they do not include effects that can only be seen later, such as delayed development, learning disabilities, lower intelligence, asthma, autism - all effects found in some studies.

The other was a California Department of Pesticide Regulation (CDPR) 2016 report on air monitoring results (from 6 sites) of 32 chemicals (pesticides and breakdown products) in California. Some pesticides were not detected, some were only at trace amounts, and some were detected at higher amounts  - and the amounts fluctuated over the year and from site to site. [NOTE: They did not monitor for 2 widely used pesticides: glyphosate, which is in Roundup, and 2,4-D. Hmm...]. A Kern County high school monitoring site showed levels of the pesticide chlorpyrifos more than 18 times higher than EPA's "level of concern for pregnant women" - but yet these levels are considered OK for the general public.

Chlorpyrifos is "controversial" in that scientists (including EPA scientists), medical professionals, and farmworker organiztions asked that its use be banned due to its serious health effects on humans, but this year EPA chief Scott Pruitt refused to do so (he gave in to pesticide industry lobbying). The bottom lineWhat effect do the mixtures of pesticides (at chronic low levels) that we're exposed to have on us? Unknown. 

From Medical Xpress: Researchers unravel the negative effects of pesticide exposure on birth outcomes

Although common opinion holds that exposure to pesticides increases adverse birth outcomes, the existing body of scientific evidence is ambiguous..... A new study by researchers at UC Santa Barbara addresses the issue in a novel way—by analyzing birth outcomes in California's San Joaquin Valley. With more than one-third of the country's vegetables and two-thirds of its fruits and nuts produced there, the San Joaquin Valley, not surprisingly, is a heavy pesticide-use region. The UCSB team investigated the effect of exposure during pregnancy in this agriculturally dominated area and observed an increase in adverse outcomes accompanying very high levels of pesticide exposure

"For the majority of births, there is no statistically identifiable impact of pesticide exposure on birth outcome," said lead author Ashley Larsen, an assistant professor in UCSB's Bren School of Environmental Science & Management. "Yet mothers exposed to extreme levels of pesticides, defined here as the top 5 percent of the pesticide exposure distribution, experienced between 5 and 9 percent increases in the probability of adverse outcomes with an approximately 13-gram decrease in birth weight."

Using individual birth certificate records for more than 500,000 single births between 1997 and 2011, coupled with pesticide use data at a fine spatial and temporal scale, the scientists were able to determine if residential agricultural pesticide exposure during gestation—by trimester and by toxicity—influenced birth weight, gestational length or birth abnormalities.

They found negative effects of pesticide exposure for all birth outcomes—birth weight, low birth weight, gestational length, preterm birth, birth abnormalities—but only for mothers exposed to very high levels of pesticides—the top 5 percent of the exposure distribution in this sample.... Numerous chemicals are used daily in close proximity to residential areas, making it difficult to ascertain a specific responsible agent. As a result, in this study, the researchers looked at the combined results from all pesticides used in the region[Original study.]

Excerpts from Beyond Pesticides: Neurotoxic Pesticide Detected in Air at High Levels in California County

The California Department of Pesticide Regulation (CDPR) released its 2016 air monitoring data where it was revealed that chlorpyrifos air concentrations for a one-month period at the air monitoring site on the campus of Shafter High School in Kern County was 39.4 nanograms per cubic meter (ng/m3) – more than 18 times higher than EPA’s level of concern for pregnant women (2.1 ng/m3).  Shafter High School is some distance from fields in an area where chlorpyrifos use is not as high as in other parts of Kern County or elsewhere in California. 

High chlorpyrifos levels at a school means that children and unsuspecting teachers and parents, especially those that may be pregnant, are breathing in unusually high levels of chlorpyrifos. Children exposed to high levels of chlorpyrifos have developmental delays, attention problems, attention-deficit/hyperactivity disorder problems, and pervasive developmental disorders.