More than five million Americans have Alzheimer’s. This devastating illness has no cure. ABC reporter Terry Moran shares his experience of watching his mother struggle with Alzheimer’s:
"The worst thing for me, I think, was that I could tell my mother knew what was happening to her; she had watched it happen to her mother. She was terrified as the disease tore apart her mind. I remember sitting with her one morning, for hours, as she said over and over to me, ‘I want to kill myself. I am going to kill myself. I wish I could kill myself.’ For hours. My mom."
Mr. Moran watched his mother lose the ability to keep track of her belongings, schedule, and forget the names of people she loved. At the same time, he grappled with a big decision: should he undergo genetic testing for Alzheimer’s? He wondered if it was really worth knowing that he might be predisposed to suffer the way his mom did.
Genes aren’t the whole story
People in situations like Mr. Moran’s can spend hours agonizing over their family history. What many might not realize is that factors in addition to our genes can also affect whether we develop Alzheimer’s. Scientists are beginning to find links between exposure to certain commonly found chemicals and Alzheimer’s.
We have no control over our genetic make-up, but effective laws and regulations can control our exposure to harmful chemicals.
Why worry about chemicals and Alzheimer’s?
Scientists don’t yet know exactly how Alzheimer’s develops, but research is turning up important clues. For instance, researchers know that a protein called amyloid-beta is very important in Alzheimer’s prognosis. People with higher levels of this protein appear more likely to develop Alzheimer’s.
While specific genes do influence how much amyloid-beta is in the brain, they aren’t the only factor. Studies show that certain chemicals, such as lead, can increase amyloid-beta accumulation in the brain. This frightening effect is worse when the exposure to lead happens early in life because the brain is less developed and thus more influenced by changes in the environment.
But wasn't lead banned?
You might think that lead isn’t used anymore, given broad awareness of its hazards. Sadly, that’s not so.
In the U.S., lead is restricted in specific uses, but not banned. In paints, the most notorious use of this toxin, up to .06% lead is still allowed. Even after the public outcry about the alarming levels of lead in children’s toys and jewelry, the law guiding the US Consumer Products Safety Commission still allows products for children under the age of 12 to contain up to 100 ppm (parts per million) of lead–or 300 ppm lead when it is deemed not technologically "feasible" to attain the 100 ppm limit in a product.
Some may think that lead in small amounts is not harmful. But we know that’s not the case. Even very small amounts of lead have been shown to cause detrimental effects on the brain and nervous system. The Center for Disease Control’s chemical profile of lead cites numerous studies demonstrating that low levels of lead can cause harm. Further, several studies like this one, performed by the director of the Children’s Environmental Health Center, indicate that there is no “safe” level of lead exposure.
PCBs: Another story of how regulations failed us
PCBs (polychlorinated biphenyls) are another group of toxic chemicals that increase the likelihood of developing Alzheimer’s. PCBs were once used in television sets, fluorescent lighting, and electrical insulators. We know now how dangerous they are, and since 1976 PCBs have been banned from commercial production and most uses in the United States.
But we learned of the danger too late. PCBs are persistent, bioaccumulative, and toxic chemicals (PBTs). They remain in the environment for a very long time and are still found today in dangerous quantities in the in soil, water, and air. Some uses that were allowed have turned out to be a continuing source of release to the environment. The U.S. Centers for Disease Control's biomonitoring data, which measures the presence of chemicals in people's bodies, indicate our continued exposure to PCBs despite their not having been used in 35 years. If PCBs had been adequately tested for safety decades ago before their widespread use, maybe their lingering presence might not be still threatening our health today.
We need to worry about other chemicals, too
Lead and PCBs aren’t the only chemicals that may increase our risks of developing Alzheimers.
Many chemicals on the market, like BPA (found in food cans and paper receipts) and certain phthalates (found in certain plastics, varnishes, paints, and fragrances) have been shown to lower testosterone levels. Lowered testosterone levels are a risk factor for Alzheimer’s. While studies have not yet linked these chemicals directly to Alzheimer’s, what we do know raises troubling questions.
There may be even more chemical contributors to Alzheimer’s risk. Identification of toxic chemicals, such as those associated with Alzheimer’s, is difficult because of weak chemical safety laws that don’t require adequate testing of the thousands of chemicals in use.
The main chemical safety law isn’t protecting us
Why are potentially dangerous chemicals used in consumer products at all? The main reason is an ineffective and outdated law called the Toxics Substances Control Act (TSCA). When TSCA was enacted in 1976, it grandfathered in the 60,000 chemicals already on the market–with no questions asked about their safety and no testing required.
And even today, TSCA does not require that new chemicals be tested before being used in everyday items. There are now over 80,000 chemicals available for use, and EPA has managed to require testing of about 2% of them. Given what we know about the potential dangers of chemicals, these numbers are frightening and unacceptable.
We can fix the law—support the Safe Chemicals Act
A lot of damage has been done. We can’t change the history of PCBs and lead. Widespread use of risky chemicals like BPA and phthalates continue in the market today.
But we have an opportunity to make things better now and for the future. The Safe Chemicals Act of 2011 would require that existing and new chemicals be found safe in order to remain on, or be introduced into, the market. Chemical manufacturers would have the burden to provide data that demonstrate their chemicals are safe, rather than government – and the public – having the burden of showing they’re not.
Some industry lobbyists are hard at work against the Safe Chemicals Act, but with support from enough concerned voters, it can pass.
Tell your Senators now how important it is to support the Safe Chemicals Act.
We can’t change our genetic risk of Alzheimer’s, or keep people like Mr. Moran and his mom from facing awful choices. But through common-sense chemical safety policies, we can make big steps toward reducing preventable risks that stack the deck against our health.
Basha Mr, Wei W, Bakheet Sa, et al. "The fetal basis of amyloidogenesis: exposure to lead and latent overexpression of amyloid precursor protein and beta-amyloid in the aging brain." Journal of Neuroscience. 2005;25(4):823-829.
Holland, J, Bandelow S, Hogervorst E. “Testosterone levels and cognition in elderly men: a review.” Applied Cognitive Research, 21 June 2011.
Jill Stein, Ted Schettler, Ben Rohrer, Maria Valenti. “Environmental Threats to Healthy Aging.” Greater Boston Physicians for Social Responsibility and Environmental Health Network. 2008.
Kyle Steenland, Misty J. Hein, Rick Cassinelli, et al, “Polychlorinated Biphenyls and Neurodegenerative Disease Mortality in an Occupational Cohort,” Epidemiology, 17, no. 1 (2006): 8–13
Maricel V. Maffini, Beverly S. Rubin, Carlos Sonnenschein and Ana M. Soto. “Endocrine Disruptors and Reproductive Health: the case of Bisphenol A.” Molecular and Cellular Endocrinology, Volums 254-255, 25 July 2006, Pages 179-186.
Pant N, Pant A, Shukla M, Mathur N, Gupta Y, Saxena D. "Environmental and experimental exposure of phthalate esters: the toxicological consequence on human sperm." Human & Experimental Toxicology, June 2011, Vol. 30 Issue 6, pages 507-514.
Wu J, Basha Mr, Brock B, et al."Alzheimer’s disease (AD)-like pathology in aged monkeys after infantile exposure to environmental metal lead (pb): evidence for a developmental origin and environmental link for AD." Journal of Neuroscience. 2008;28(1):3-