Vanguard Neurologist

Asthma is an incredibly common disorder of infancy and childhood, characterized by an allergic reaction of the bronchial tubes causing them to become narrowed and thus compromising breathing. When breathing is compromised in this manner, oxygenation of the blood declines. It has been estimated that 12.2% of children in the United States have been diagnosed with asthma (that is, greater than 1in 10 )(Summary Health Statistics for US Children, 2002, CDC). The disease affects approximately 17 million Americans with 14 deaths attributed to asthma in this country every day. Over the past two decades we have seen a dramatic rise in the incidence of asthma, particularly in younger children. The rise of asthma incidence is particularly noted in developed countries and is thought to represent continued and increasing pollution of food, air and water. Other factors known to be associated with asthma include lack of breastfeeding, asthma in a family member, exposure to secondhand cigarette smoke, dust mites, mold exposure and, what we will explore

in this entry,, exposure to chemical compounds found in plastics called phthalates. Asthma has been described as the most common disease of childhood. Symptoms include attacks of wheezing with shortness of breath, excessive mucus production, and a feeling of “tightness in the chest.” During an asthmatic attack, children typically experience a rapid heartbeat, appear distressed and anxious, have difficulty sleeping, and they demonstrate a decline in blood oxygenation. A variety of instigating factors can trigger asthmatic attacks, including pollen, dust (especially dust mites), various environmental pollutants such as chemicals, especially household chemicals, and tobacco smoke, and even certain medications including aspirin. Other triggers include food allergies (representing approximately 5% of asthma causes), changes in temperature and/or humidity, physical activity (seen in 40-90% of asthmatics), as well as exposure to animals (animal dander, fur, and insects – especially cockroaches).

In a study entitled, Asthma in preschool children: prevalence and risk factors appearing in the Journal Thorax, researchers endeavor to more fully characterize risk factors for asthma. Their findings in evaluating children 3-5 years of age revealed that a history of breastfeeding was associated with a 59% reduction of risk, while the risk of asthma was doubled in children having a parent with a history of asthma. Having had a serious respiratory infection in the first two years of life also doubled the risk of having asthma. In research published by the National Institutes of Health specifically looking at the risk of asthma in relation to breastfeeding in children from birth to age 72 months, they again found a remarkable reduction of asthma risk in children who had been breastfed compared to those who were not. Interestingly, breastfed children demonstrated a reduction of risk of asthma, even when exposed to environmental tobacco smoke. While this is not an indication that if you breastfeed your child it is okay to expose him or her to cigarette smoke, what it does indicate is the very important protective effect of breastfeeding in terms of reducing risks for asthma, even in the presence of secondhand smoke.

I must repeat these statistics with reference to asthma in children. That is, 1:10 children have been diagnosed as having asthma. This is a potentially fatal disease which, as we will see, can have a significantly detrimental effect on several critically important areas of brain function. Researchers are hard at work to come up with an explanation as to this sudden and dramatic increased incidence of asthma in our children. While those risk factors described above are certainly important, new research reveals an even more sinister cause lurking in all of our homes. Swedish researchers working with American researchers at Rutgers University published a groundbreaking article in 2004 entitled, The Association between Asthma and Allergic Symptoms in Children and Phthalates in House Dust: A Nested Case-Control Study. These researchers determined that there is a stunning relationship between the concentration of phthalates in dust collected in the homes of children, and their risk for asthma. Phthalates are a group of chemical compounds that we all must learn more about. They are widely used in industry and are virtually ubiquitous. Current production of these dangerous chemicals now totals approximately 1 billion pounds per year world wide. Phthalates are used as additives to hairsprays, softeners of plastics, in wood finishes, perfumes, fragrance-containing soaps, shampoos, nail polish and other beauty products, and, most troubling, a large number of soft plastic toys.

Generally, phthalates to which we are exposed are undetectable, but the so-called “new car smell” that has become so attractive is actually out gassing of phthalates from the hard plastic in the car’s interior. While the dangers of high-dose exposure to phthalates has been known for years, it is only quite recently that scientists have begun to understand the significant risk of even low levels of phthalate exposure. There is now a clear and undisputable relationship of even low levels of phthalate exposure to abnormalities in development of the male reproductive tract, including malformation of the penis (hypospadias) as well as abnormal sperm development and low sperm count. In fact, there is now described in scientific literature “The Phthalate Syndrome,” which had previously been observed in experimental rodents, but is now seen in humans. Studies are now demonstrating detectable levels of phthalates in “all children.”

In one recent California study published in the Bulletin of Environmental Contamination and Toxicology, SpringerLink – Journal Article , researchers found high levels of phthalate metabolites in the urine of all children examined and, interestingly, reported that these levels were significantly higher when compared to adult levels. In discussing phthalates, the researchers stated that “…exposure on a body weight basis may be at least twice as high for these children compared to the adults…” Because of the overwhelming scientific demonstration that exposure to plastic toys containing phthalates represents a very significant health risk to infants and children, the European Parliament voted on July 5, 2005 to prohibit the use of three phthalate plasticizers in toys and child care items. Further, they restricted three other phthalate-based plasticizers throughout the entire European Eunion. As Merkos Kyprianou, European Commissioner for Health and Consumer Protection stated, “Our action on phthalates shows that when a risk is identified, the European Union can act effectively to protect the health of its children.”

This is not the case in the United States of America. While several large US toy manufacturers, including Mattel and Disney, have supported a phase out of these toxic and ubiquitous chemicals, currently this is only voluntary. While Commissioner Kyprianou described how effectively the EU protects the health of its children, it does not appear that children’s health in this country is as high on the priority list. Getting back to the study relating phthalates and asthma, the purpose of the study was to investigate the association between asthma and phthalate exposure. Called to our attention, first the fact that the dramatic rise in the incidence of asthma in the past 30 years, obvious speaks to an environmental cause as opposed to some genetic change. Their findings demonstrated a profound relationship between phthalate levels in dust samples taken from homes and risk for asthma for children living in that environment. While previous studies have demonstrated high levels of phthalate in home dust from a variety of locations including Cape Cod Massachusetts, Berlin Germany, as well as Scandinavian countries, this was the first study to clearly demonstrate the relationship between phthalate levels and asthma risk. This showed specific relationships between asthma risk and the presence of PVC (vinyl) flooring in a child’s bedroom with higher levels of phthalate dust in those areas, as well. They concluded, “This study demonstrates associations between “phthalate” concentration in dust and selected allergies and asthma. Although multiple factors are likely responsible for the increase in allergies and asthma that have been documented in developed countries over the past 30 years, it is striking that these increases have occurred during a period when plasticized products have become ubiquitous in the homes, schools, and workplaces of the developed world.” While current science does not clearly demonstrate a significant relationship between phthalate exposure (urinary phthalate levels) and developmental problems in the child’s brain, the effects upon the human immune system are, in fact, well described. The relationship with asthma is now clearly supported by well-respected scientific research. It is this relationship with asthma that does link phthalate exposure to not only problems with brain function, but brain development, as well.