Berkeley — Children who were exposed to organophosphate pesticides while still in their mother’s womb were more likely to develop attention disorders (ADHD) years later, according to a new study by researchers at the University of California, Berkeley.

The new findings, to be published Aug. 19 in the journal Environmental Health Perspectives (EHP), are the first to examine the influence of prenatal organophosphate exposure on the later development of attention problems. The researchers found that prenatal levels of organophosphate metabolites were significantly linked to attention problems at age 5, with the effects apparently stronger among boys.

Earlier this year, a different study by researchers at Harvard University associated greater exposure to organophosphate pesticides in school-aged children with higher rates of attention deficit hyperactivity disorder (ADHD) symptoms.

“These studies provide a growing body of evidence that organophosphate pesticide exposure can impact human neurodevelopment, particularly among children,” said the study’s principal investigator, Brenda Eskenazi, UC Berkeley professor of epidemiology and of maternal and child health. “We were especially interested in prenatal exposure because that is the period when a baby’s nervous system is developing the most.”

The study follows more than 300 children participating in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS), a longitudinal study led by Eskenazi that examines environmental exposures and reproductive health. Because the mothers and children in the study are Mexican-Americans living in an agricultural community, their exposure to pesticides is likely higher and more chronic, on average, than that of the general U.S. population.

Yet, the researchers pointed out that the pesticides they examined are widely used, and that the results from this study are a red flag that warrants precautionary measures.

“It’s known that food is a significant source of pesticide exposure among the general population,” said Eskenazi. “I would recommend thoroughly washing fruits and vegetables before eating them, especially if you’re pregnant.”

Organophosphate pesticides act by disrupting neurotransmitters, particularly acetylcholine, which plays an important role in sustaining attention and short-term memory.

“Given that these compounds are designed to attack the nervous system of organisms, there is reason to be cautious, especially in situations where exposure may coincide with critical periods of fetal and child development,” said study lead author Amy Marks, who was an analyst at UC Berkeley’s School of Public Health at the time of the study.

Many of these same UC Berkeley researchers are also finding that children with certain genetic traits may be at greater risk, a finding that is being published the same day in a separate EHP paper. That study found that 2-year-olds with lower levels of paraoxonase 1 (PON1), an enzyme that breaks down the toxic metabolites of organophosphate pesticides, had more neurodevelopmental delays than those with higher levels of the enzyme. The authors suggest that people with certain PON1 genotypes could be particularly vulnerable to pesticide exposure.

In the study on attention problems, researchers tested for six metabolites of organophosphate pesticides in mothers twice during pregnancy and in the children several times after birth. Together, the metabolites represent the breakdown products of about 80 percent of all the organophosphate pesticides used in the Salinas Valley.

The researchers then evaluated the children at age 3.5 and 5 years for symptoms of attention disorders and ADHD using maternal reports of child behavior, performance on standardized computer tests, and behavior ratings from examiners. They controlled for potentially confounding factors such as birthweight, lead exposure and breastfeeding.

Each tenfold increase in prenatal pesticide metabolites was linked to having five times the odds of scoring high on the computerized tests at age 5, suggesting a greater likelihood of a child having clinical ADHD. The effect appeared to be stronger for boys than for girls.

While a positive link between prenatal pesticide exposure and attention problems was seen for 3.5-year-olds, it was not statistically significant, a finding that did not surprise the researchers.

“Symptoms of attention disorders are harder to recognize in toddlers, since kids at that age are not expected to sit down for significant lengths of time,” said Marks. “Diagnoses of ADHD often occur after a child enters school.”

The UC Berkeley researchers are continuing to follow the children in the CHAMACOS study as they get older, and expect to present more results in the years to come.

The findings add to the list of chemical assaults that have been linked to ADHD in recent years. In addition to pesticides, studies have found associations with exposure to lead and to phthalates, which are commonly used in toys and plastics.

“High levels of the symptoms of ADHD by age 5 are a major contributor to learning and achievement problems in school, accidental injuries at home and in the neighborhood, and a host of problems in peer relationships and other essential competencies,” said UC Berkeley psychology professor Stephen Hinshaw, one of the country’s leading experts on ADHD, who was not part of this study. “Finding preventable risk factors is therefore a major public health concern.”

Literature: University of California – Berkeley, Prenatal exposure to pesticides linked to attention problems, 19-Aug-2010.

Related Articles:

• Pesticides in kids linked to ADHD- Attention-Deficit/Hyperactivity Disorder, study finds
• Western Diet linked to ADHD
• Groups Seeking Ban on Organophosphate Pesticide Go to Federal Court
• Common household pesticides linked to childhood cancer cases in Washington area
• Anxiety in adult female mice following perinatal exposure to Chlorpyrifos

Chlorpyrifos – Outlawed in homes and gardens, pesticide is still sprayed on food crops

Community groups joined environmental advocates in filing a lawsuit at July 22th to force the Environmental Protection Agency to decide once and for all whether or not it will ban the toxic pesticide chlorpyrifos.

Chlorpyrifos — sprayed on corn, oranges, almonds and other crops — is acutely poisonous and is among a class of pesticides initially developed for World War II-era chemical warfare. Short term effects of exposure to chlorpyrifos include chest tightness, blurred vision, headaches, coughing and wheezing, weakness, nausea and vomiting, coma, seizures, and even death. Prenatal and early childhood exposure has been linked to low birth weights, developmental delays and other health effects.

In recognition of the particular risks the chemical presents for children, EPA banned residential uses of chlorpyrifos in 2001. But the pesticide is still widely used in fields and orchards across the country. This continued use puts nearby rural communities in harm’s way, and chlorpyrifos ends up in our nation’s food and water supplies, leading to even more widespread exposure (click here for a list of foods with documented chlorpyrifos residue.)

Luis Medellin has experienced the dangers of this pesticide firsthand. Medellin lives with his parents and three little sisters in the agricultural town of Lindsay, California, where chlorpyrifos is sprayed routinely on the orange groves surrounding his home. During the growing season, the family is awakened several times a week by the sickly smell of nighttime pesticide spraying. What follows is worse: searing headaches, nausea, vomiting. After undergoing testing for pesticides in his body, the 24-year-old Medellin discovered concentrations of chlorpyrifos breakdown compounds nearly five times the national average for adults, as calculated by the Centers for Disease Control and Prevention.

“When I found out I had this chemical in my body, it scared me. But what really worries me is how my little sisters might be affected.” said Medellin, a community organizer with the Lindsay-based El Quinto Sol. “I wish the growers would stop using such dangerous chemicals so my family and I can be safe.”

In September 2007, Natural Resources Defense Council (NRDC) and Pesticide Action Network North America (PANNA) filed a petition with EPA asking the agency to ban chlorpyrifos. In the nearly three years since, the agency has not responded. Today’s lawsuit, filed by the nonprofit environmental law firm Earthjustice on behalf of NRDC and PANNA, would force EPA to make a decision on the pesticide’s ban.

“This dangerous pesticide has no place in our fields, near our children, or on our food,” said Earthjustice attorney Kevin Regan. “We’re asking a court to rule so that EPA will finish the job and ban this poison.”

An estimated 8 to 10 million pounds of chlorpyrifos are applied to U.S. crops each year (click here for a map showing where this pesticide is used.)

“The overwhelming evidence shows that chlorpyrifos is dangerous, especially to children and fieldworkers,” said Aaron Colangelo, a senior attorney with NRDC. “There’s no good reason for EPA to take three years to decide what to do about it.”

Exposure to chlorpyrifos in agricultural communities is widespread. California Air Resources Board monitoring in the state’s San Joaquin Valley detected chlorpyrifos in one-third of all ambient air samples, sometimes at levels that pose serious health risks to young children. Monitoring by PANNA and community groups in Washington state and Luis Medellin’s hometown of Lindsay, California has shown that daily exposure to chlorpyrifos can be substantial, regularly exceeding the “acceptable” 24-hour acute dose for a one-year-old child established by the EPA.

In one 2000 incident, dozens of students and staff at an elementary school in Ventura, CA fell ill after chlorpyrifos applied to a nearby lemon orchard drifted onto school grounds.

“Chlorpyrifos is among a class of pesticides that targets developing nervous systems — in insects and humans alike. These pesticides are linked to a host of devastating diseases ranging from ADHD to childhood brain cancer,” said PANNA senior scientist Dr. Margaret Reeves. “Their human health costs are just too high and farmers are farming successfully without them. There’s no defensible reason for continuing to use chlorpyrifos.”

Reference: EarthJustice, Release: Groups Seeking Ban on Toxic Pesticide Go to Federal Court, New York, July 22, 2010.

BACKGROUND

• A copy of the lawsuit
• A fact sheet on chlorpyrifos
• A map documenting where chlorpyrifos is used
• A list of foods with documented chlorpyrifos residue
• A study linking chlorpyrifos to low birth weights
• A study linking chlorpyrifos to developmental delays

Parkinson’s disease (PD), one of the most common neurodegenerative disorders, is characterised by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) to the striatum (ST), and involves oxidative stress. Mulberry fruit from Morus alba L. (Moraceae) is commonly eaten, and has long been used in traditional oriental medicine. It contains well-known antioxidant agents such as anthocyanins.

The present study examined the protective effects of 70 % ethanol extract of mulberry fruit (ME) against neurotoxicity in in vitro and in vivo PD models. In SH-SY5Y cells stressed with 6-hydroxydopamine (6-OHDA), ME significantly protected the cells from neurotoxicity in a dose-dependent manner.

Other assays demonstrated that the protective effect of ME was mediated by its antioxidant and anti-apoptotic effects, regulating reactive oxygen species and NO generation, Bcl-2 and Bax proteins, mitochondrial membrane depolarisation and caspase-3 activation.

In mesencephalic primary cells stressed with 6-OHDA or 1-methyl-4-phenylpyridinium (MPP+), pre-treatment with ME also protected dopamine neurons, showing a wide range of effective concentrations in MPP+-induced toxicity.

In the sub-acute mouse PD model induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), ME showed a preventative effect against PD-like symptoms (bradykinesia) in the behavioural test and prevented MPTP-induced dopaminergic neuronal damage in an immunocytochemical analysis of the SNpc and ST.

These results indicate that ME has neuroprotective effects in in vitro and in vivo PD models, and that it may be useful in preventing or treating PD.

Literature:

Kim HG, Ju MS, Shim JS, Kim MC, Lee SH, Huh Y, Kim SY, Oh MS., Mulberry fruit protects dopaminergic neurons in toxin-induced Parkinson’s disease models, Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Dongdaemun-gu, Seoul 130-701, South Korea, Br J Nutr. 2010 Jul;104(1):8-16.

Berkeley — Pregnant women with higher blood levels of a common flame retardant had altered thyroid hormone levels, a result that could have implications for fetal health, according to a new study led by researchers at the University of California, Berkeley.

“This is the first study with a sufficient sample size to evaluate the association between PBDE flame retardants and thyroid function in pregnant women,” said the study’s lead author, Jonathan Chevrier, a UC Berkeley researcher in epidemiology and in environmental health sciences. “Normal maternal thyroid hormone levels are essential for normal fetal growth and brain development, so our findings could have significant public health implications. These results suggest that a closer examination between PBDEs and these outcomes is needed.”

PBDEs, or polybrominated diphenyl ethers, are a class of organobromine compounds found in common household items such as carpets, textiles, foam furnishings, electronics and plastics. U.S. fire safety standards implemented in the 1970s led to increased use of PBDEs, which can leach out into the environment and accumulate in human fat cells.

Studies suggest that PBDEs can be found in the blood of up to 97 percent of U.S. residents, and at levels 20 times higher than those of people in Europe. Because of California’s flammability laws, residents in this state have some of the highest exposures to PBDEs in the world.

“Despite the prevalence of these flame retardants, there are few studies that have examined their impact on human health,” said the study’s principal investigator, Brenda Eskenazi, UC Berkeley professor of epidemiology and of maternal and child health. “Our results suggest that exposure to PBDE flame retardants may have unanticipated human health risks.”

The new study, to be published June 21 in the journal Environmental Health Perspectives, is the second study to come out this year from Eskenazi’s research group linking PBDEs to human health effects. Eskenazi was the principal investigator on the earlier study that found that women with higher exposures to flame retardants took longer to get pregnant.

In the new study, the researchers analyzed blood samples from 270 women taken around the end of their second trimester of pregnancy. The women in the study were part of a larger longitudinal study from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) that examines environmental exposures and reproductive health.

The researchers measured concentrations of 10 PBDE chemicals, two types of thyroxine (T4) and thyroid-stimulating hormone (TSH). They controlled for such factors as maternal smoking, alcohol and drug use, and exposure to lead and pesticides.

Analysis focused on the five PBDE chemicals that were detected most frequently and are components of a mixture called pentaBDE. The researchers found that a 10-fold increase in each of the PBDE chemicals was associated with decreases in TSH ranging from 10.9 percent to 18.7 percent. When the five PBDEs were analyzed together, a tenfold increase was linked to a 16.8 percent decrease in TSH.

The study did not find a statistically significant effect of PBDE concentrations on levels of T4. With one exception, all the women in the study with low TSH levels had normal free T4 levels, which corresponds to the definition of subclinical hyperthyroidism. The study found that odds of subclinical hyperthyroidism were increased 1.9 times for each tenfold increase in PBDE concentrations.

“Low TSH and normal T4 levels are an indication of subclinical hyperthyroidism, which is often the first step leading toward clinical hyperthyroidism,” said Chevrier. “Though the health effect of subclinical hyperthyroidism during pregnancy is not well understood, maternal clinical hyperthyroidism is linked to altered fetal neurodevelopment, increased risk of miscarriage, premature birth and intrauterine growth retardation.”

Exactly how flame retardants influence TSH levels is unclear, the researchers said, but animal studies have shown that certain PBDEs can mimic thyroid hormones.

In addition to the commercial mixture pentaBDE, octaBDE and decaBDE have been developed for use as commercial flame retardants. PentaBDE and octaBDE have both been banned for use by the Stockholm Convention on Persistent Organic Pollutants, the European Union and eight U.S. states, including California, but they are still present in products made before 2004.

The production of decaBDE by major manufacturers is scheduled to be phased out in the United States by 2013. However, pentaBDE and decaBDE are being replaced by new brominated and chlorinated compounds whose impact on human health is not yet clear, the researchers noted.

Literature: University of California – Berkeley, Flame retardant linked to altered thyroid hormone levels during pregnancy, June, 21, 2010.

International Appeal from Wuerzburg

The European Academy for Environmental Medicine (EUROPAEM) invited many renowned national and international scientists and health care professionals to a medical conference held in Wuerzburg, Germany from April 23 to April 25, 2010. These professionals were from the fields of environmental medicine, toxicology, immunology, neurology and genetics and other health fields as well as physicians and dentist. Also in attendance were representatives of patient initiatives. The theme of this international medical conference was Science Meets Practice. It dealt specifically with the issues of Neuro- Endocrine- Immunology and their importance in environmental medicine.

Greatly concerned, participants noted the increasing prevalence of chronic multisystem illnesses such as multiple chemical sensitivity (MCS), chronic fatigue syndrome (CSF), fibromyalgia (FMS) as well as cardiovascular diseases, metabolic syndrome, neurodegenerative diseases, auto immune diseases, and cancer.

At the conference it was impressively demonstrated that these chronic diseases are based on similar pathological mechanisms. Common mechanisms are chronic inflammatory processes influenced by environmental factors including chemical pollutants, biological infectious agents, and electromagnetic field (EMF) triggers.

Chronic diseases mean long-term patients and such patients require consecutive higher medical costs. This often leads to social exclusion of the affected people. Facing the appalling reports of Europe´s growing financial constraints, especially in public health, a further increase of chronic illnesses will accelerate the ongoing collapse of the National Health Service and medical insurance companies in Europe. Remedy is only possible with a change of priorities from today´s unilaterally symptomatic oriented medicine to causally oriented medicine focusing on cost-effective primary prevention.

Conference participants addressed an urgent appeal to the European environment and health ministers, to the European Commission, the European parliamentarians, national governments and to the directors of social and private insurance companies. They urge them to take these findings and developments into serious consideration, stressing and weighting financial investments primarily in prevention, precaution and best early detection and diagnosis of these chronic and environmentally related illnesses.

All over Europe this requires the full awareness of these research findings of the practicing physicians of environmental medicine and their integration into university research and teaching. The European governments are asked to finally implement the already ratified decisions of the Fourth Ministerial Conference on Environment and Health Ministers held in Budapest in 2004.

This appeal was unanimously adopted by the congress.

Wuerzburg April 25, 2010

For the board of EUROPAEM,

Jean Huss, Vice-Chairman

Dr. Kurt Mueller, Chairman

Dr. Peter Ohnsorge, Managing Chairman

Dr. Hans-Peter Donate, Press, Responsible

• German Version – International Appeal from Wuerzburg
• Japanese Version – International Appeal from Wuerzburg / Thanks to Takeshi for translation.