Archive for the ‘medically-oriented background info’ Category

Mutating the deadly H5N1 flu virus

Saturday, May 5th, 2012

This ferret is healthy

There's been a recent controversy as to whether potentially dangerous medical information should be made available to the public. Now it's happened and I'm somewhat less concerned than I was a few weeks ago. The online version of Nature just published the work of the University of Wisconsin group on making the Highly Pathogenic Avian Influenza (HPAI) type A H5N1 virus transmissible from mammal to mammal, in this case ferrets.

This is potentially a terrible disease; it's killed 355 of the 602 humans (~59%) known to have contracted the HPAI A(H5N1) virus to date. None of those cases involved human to human spread of the flu bug involved. But that's roughly 600 times as lethal as an "ordinary" flu pandemic and more than 20 times as deadly as the 1918 flu.

So why am I less worried than I was?

When I read the article in Nature in detail (and it's tough slogging even for a physician), I realized that the virus, in the process of making it capable of airborne transmission, had also been made less virulent. None of the ferrets used as research subjects died of the disease . The new virus was also found to be preventable by a vaccine and treatable with one of the existing anti-flu medications.

The other thing I quickly understood is this is not a process that the average man (or woman) on the street or even the vast majority of scientists and/or physicians could duplicate. It involved an enormously complex set of laboratory procedures, many of which would demand long-term expertise and experience in the field. Theoretically a virology lab could be influenced by links to a terrorist group or have their own "ultra-green" agenda; neither possibility sounds at all likely to me.

The other paper, detailing the work done on HPAI A(H5N1) in Rotterdam, is yet to be published. That one has me more concerned, but I've just read a paper "Dangerous for ferrets: lethal for humans?" that carefully explores the question involved.

The authors reminded us that a previous paper had discussed the recreation of the so-called Spanish flu virus that killed 50 million worldwide in 1918. I'll write about that in detail some other time, but when that publication appeared, its authors were hailed as heroes, not as dolts.

The work of Ron Fouchier, a senior figure at the Erasmus Medical Center in Holland took the virology world by storm. He first announced his group's alteration of H5N1 at an international meeting in Malta in September, 2011. Initially his variant of the flu virus was thought to be much more deadly to ferrets than the UW bug. A May 3, 2012 paper in Time Healthland discusses the infighting among scientists that followed, but notes that Fouchier's paper should be out in the magazine Science in the near future.

Apparently Fouchier's mutated virus also turned out to be less of a ferret-killer than was initially thought.

There's the normal flu season and the other kind

But that's not the major issue here. Most of those working in the virology field feel a natural mutation of H5N1 or H1N1 or other flu strains is more to be feared than anything produced in a lab. Yet the relatively benign 1977 H1N1 flu pandemic, so-called Russian flu, may have escaped from deep freeze in a lab.

Every year has its flu season; some are much worse than others.



Tick-borne Disease part four: the chronic Lyme Disease controversy

Monday, April 30th, 2012

Sometimes you need an expert panel to resolve a controversy

A March 27, 2012, Wall Street Journal article, "This Season's Ticking Bomb,"predicted that the unusually warm weather most of the country has been experiencing meant we would also see many more cases of tick-borne diseases, If you click on the link, be sure to look at the section called "View Interactive" to get to a series of suggestions on reducing your family's risk of tick bites.

The article itself talked mainly about Lyme disease. There is an International Lyme and Associated Diseases Society (ILADS), but much of their Lyme disease website information was from 2006.  They are on one side of a major medical controversy, how to care for patients who have had Lyme disease and continue to have problems, especially with short-term memory, fatigue, or musculoskeletal issues, well after they have been appropriately treated with short-term antibiotics.

Two articles were published on this subject in 2007-8: the first one, "Chronic Lyme Disease: an appraisal"  is available online; the other, "A Critical Appraisal of Chronic Lyme Disease," appeared in the New England Journal of Medicine.

The real question is whether the bacteria involved, Borrelia burgdorferi, remains in the body of a patient after relatively short-term antibiotic therapy and if a considerably longer course of drug treatment is warranted. The ILADS says, "Yes" to both questions and refers back to a Harvard & Tufts study published in the Annals of Internal Medicine in 1994.

The most recent CDC online information states that 10 to 20% of those who receive standard therapy for Lyme disease will have some lingering symptoms. However they term this "Post-treatment Lyme disease Syndrome." I found that European cases of Lyme and similar diseases are usually caused by our Borrelia borgdorferi's cousins; data from that literature may not be relevant here.

In November 2006, the Attorney General of Connecticut (CAG) pushed the Infectious Disease Society of America (IDSA) into a detailed review of their Lyme Disease guidelines by starting an investigation to decide if they had violated existing antitrust laws. By April 2008, the IDSA and the CAG agreed to end the probe by convening a review panel, with members from Duke, the NIH, Dartmouth, the U.S. Navy, Baylor, Tulane and other centers, to decide if the original guidelines had been based on sound medical/scientific evidence and if they needed changes. An MD, PhD medical ethicist screened panel members for any conflict of interest. A public hearing was held to include other viewpoints. The Final Report of the Review Panel was published in April, 2010.

Some will think the decision ties their doc's hands.

It basically upheld the 2006 IDSA guidelines, but added 1). In some cases (non-pregnant adults or kids 8 or older who've had a tick of the Lyme-carrying species attached for 36+ hours in an area with high infectivity rate of ticks with B. burgdorferi), a single dose of doxycycline (if they have no allergy to this drug) may be given  if the tick was removed within 72 hours; 2). Antibiotics are appropriate for adults and children 8 or older with early, uncomplicated Lyme disease; 3).  "Reports purporting to show the persistence of viable B. burgdorferi organisms after treatment with recommended regimens for Lyme disease have not been conclusive or corroborated by controlled studies." and 4). "The risk/benefit ratio from prolonged antibiotic therapy strongly discourages prolonged antibiotic courses for Lyme disease.

And at the end of the report, they mentioned a disease I'd never heard of; I'll do some more reading and write about it later.





tick-borne disease part 3: Vanilla Lyme

Sunday, April 29th, 2012

I'm finally ready to write about Lyme disease and will start with the basics; it results from the bite of a tiny tick and causes well over 20,000 cases per year in the US. It's most common in the North-East and the Middle-West, most frequently affects kids under 16 (especially girls--ticks can hide in long hair) and can be prevented (DEET to keep ticks away; post-hike "tick checks"); prompt antibiotic treatment is indicated if signs or symptoms/history suggest this entity.

you have to look closely

I'll save the controversy about post-treatment Lyme disease syndrome, AKA Chronic Lyme Disease, for another post as that issue deserves its own discussion.

We first heard about Lyme disease some years back when a relative was afflicted by a severe case of the illness. One of the best resources I've subsequently found on Lyme came from an emeritus at the place I got my formal medical training, the University of Wisconsin, now termed UW-Madison. Dr. Kenneth Todar, a PhD in the Department of Bacteriology, has a superb online textbook and his chapter on Lyme Disease is an extremely helpful reference.

The initial realization of the disease itself happened thirty-seven years ago. The website for NIAID, the National Institute of Allergy and Infectious Diseases has a great, though somewhat convoluted, detailed history of Dr. Willy Burgorfer's isolation of the spirochete bacteria that would eventually be named for him.

In brief, there had been a 1975 outbreak that resulted in a considerable number of children living in or near the town of Lyme, Connecticut, being diagnosed with juvenile rheumatoid arthritis. The Yale physician looking for the cause of these Lyme disease cases realized most occurred in children who spent time in wooded areas and whose initial symptoms occurred in the midst of the tick season, summer. He thought the deer tick might be involved and, eventually, Dr. Burgdorfer  found the spirochetes in deer ticks sent to him from the affected area.

IDSA,  the Infectious Disease Society of America, has a one-pager titled "Ten Facts You Should Know About Lyme Disease" and the New York Health Department has a similar short discussion of Lyme Disease.

one example of a typical rash

To reiterate the concepts I think are crucial:  the groups involved, kids under 16 with more girls than boys, plus adult men;. the areas of the country: 93% of cases occur in ten states: Connecticut, Delaware, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island and Wisconsin; the fact that early diagnosis is clinical (antibodies develop later); the tiny size (two mm) of the tick nymphs which usually are the agents for transmission of the bacteria; the difficulty in diagnosis unless the characteristic rash is present; and the need for prompt antibiotic treatment in prevention.

Symptoms begin to show anywhere from a few days to a month after the bite, but, in most cases, the tick itself has to remain attached for a day and a half to transmit the bacteria and there is no person to person spread of this disease. Early signs, in the absence of the characteristic rash, are very non-specific.

There is a sizable percentage of patents with Lyme who have long-term sequelae. I'll write about them next time.

Tick-borne disease part two: Tick paralysis & neurotoxins

Monday, April 23rd, 2012

I had almost finished my post on Colorado tick-borne diseases when I noticed an entity I was unfamiliar with, Tick paralysis.  The CDC's comment on this says it's a "loss of muscle function that results from a tick bite." But as I read other websites, it's also the only tick-borne disease that's not caused by an infectious organism, e.g., a bacteria or a virus. Female, egg-laden ticks produce a neurotoxin, a substance poisonous to the normal function of the nervous system.

Typically children under 16, more girls than boys, are affected, and may develop an acceding paralysis, with leg weakness that can rise to the truck within a few hours and potentially cause death.

But if the tick, mostly found on the scalp, is removed, the symptoms usually resolve rapidly.

This particular chemical or mix of chemicals (it's never been identified), is junior league compared to some of its cousins.

choose your sushi chef wisely

The other neurotoxins you may have heard about much more potent. Fugu poisoning  caused by eating a puffer fish/blow fish, was apparently found over 3,000 years ago in ancient Egypt and documented in the 1800s by Captain Cook's journals of exploration. US cases are rare and the fish in question is found off Florida's coast, the Gulf of Mexico and Baja California. But restaurants in Japan and Korea have served it as a delicacy for thousands of years. The chefs who do so go through rigorous training and have to pass both written and hands-on exams before they earn the license to prepare it in a restaurant.

The fish itself can only be offered in grocery store with a permit and, since the toxin, a thousand times as potent as cyanide, is mostly found in the skin, ovaries and liver of the fish, selling them whole is forbidden. There's a great 2009 New York Times article on eating fugu here. I'm not about to try it myself.

It started as a way to catch dinner

And then there's curare, the poison applied to darts in South America which caused paralysis of the muscles used in breathing. It was basically used in hunting as the preparation of this toxic brew (the name actually has been used for a number of substance, mostly made from a poisonous bark) was too laborious for it to be used in fighting other tribes. Eating the flesh of birds or mammals killed by this highly potent mixture has no toxic effect on humans. I'm unaware of any history of hunting using blowguns with curare-tipped darts in the US; instead  curare was used medically, initially in mitigating the seizures that resulted from shock therapy, later in keeping patents immobilized during some surgical procedures. Other drugs eventually were developed to replace it.




Tick paralysis affects cows and sheep, killing thousands, in other segments of the globe. Human cases in the US cases are uncommon and mostly occur in children under 16. Once the tick is removed the symptoms normally  go away rapidly, but rarely severe paralysis can develop before the tick is found and lead to death, Most commonly the tick is embedded in the scalp and two to seven days after it feeds, the child develops weakness in both legs. If nothg is done, the weakness can progress upward and eventually lead to respiratory failure.

Another initial sign of this disease is ataxia, defined on a Mayo Clinic website as a "Lack of muscle coordination during voluntary movements." Tick bites can cause this syndrome without obvious muscle weakness, so be alert if your kids

Rabies and pet care

Tuesday, April 17th, 2012

make sure your dog's rabies vaccination is up to date

We got an older dog, a thirty-pound Tibetan terrier, eight months ago after not having a pet in the home for three years. He's had all his immunizations, but he's due for a repeat rabies shot in June. We plan to travel via car with him for the month of October and want to cross the Canadian border to see Vancouver. So we asked friends who have two much larger dogs and live in Washington State if they've been able to take their dogs into Canada.

"It's no problem as long as you bring proof that his rabies vaccination is current," my friend Bob said.

We joined the Rocky Mountain Tibetan Terrier Association and got their newsletter. One section was on preventing dog attacks, both outside the home and at home. The information came from the American Veterinary Association. More than 60% of dog bite victims are children; they need to learn not to play rough with family pets. One comment said, "Never put your face directly in front of a dog--even in play."

'Guilty as charged,' I thought. Yoda and I play and he often licks my face. I don't plan to change my behavior, but I will mention the ideas to the parents of his favorite kid, who is now one and a half years old. I do think the recommendation makes sense, for children in particular.

bats may carry the disease

So why is this important? I found an NIH National Library of Medicine article on rabies which said  that deadly viral infection is spread by infected animals. In the US the number of cases has fallen dramatically and most bites from rabid animals involve non-canines: bats, raccoons, foxes and skunks as well as cats are mentioned. We spend over $300 million a year on rabies prevention with the vast majority of that going to pet immunizations.

Worldwide rabies statistics are quite different:  over 90% of human exposure to rabies and over 99% of deaths are due to rabid dogs. Many developing countries, in spite of some having programs to vaccinate dogs and get rid of strays, can't afford a complete program.

If your child or anyone else is bitten by a non-vaccinated animal, then immediate medical care is absolutely crucial. The CDC has an online helpful description of appropriate wound care and rabies post-exposure vaccinations. Let's be clear: if your child or you are bitten, even by a beloved pet of yours that has had its shots, see your doctor right then or go to an ER. Animal bites can cause many complications outside of rabies.

Why is this so important? Well, I just read an article about a  survivor from clinical rabies, an eight-year-old girl from a non-urban area on the West Coast. That's exceedingly rare!

Yes, that's true; rabies is uniformly fatal...unless it's prevented. In the US, there have been only three people who got rabies and survived. So urgent treatment with a series of shots of both human rabies immune globulin and rabies vaccine is critical.

Don't delay; save a life.


Medical Waste: Part two

Sunday, April 15th, 2012

this ECG is normal

In my last post, about trying to decrease the incredible expense of US health care, I gave a link to the ideas Dr. Donald Berwick had outlined in the April 11th edition of JAMA. He thinks we could save huge amounts in six areas: failure of care delivery; failure of care coordination; overtreatment; administrative complexity; pricing failures and fraud & abuse.

Now I'd like to look at a few specific examples.

The same JAMA edition had a research article titled "Association of Major and Minor ECG Abnormalities with Coronary Heart Disease Events" It detailed the followup of nearly 2,200 people in my age range and up (they were 70 to 79) who were in the Health, Aging and Body Composition Study. Thirteen percent had electrocardiograms with minor changes when the study started; twenty-three percent had more significant changes. Both kinds of ECG changes were associated with an increased likelihood of having coronary artery disease (CHD) during the subsequent years.

Now ECGs are relatively cheap and can be done in many settings. But the senior author, Dr. Reto Auer, said in an interview for a publication called heartwire "Our data do not permit one to say anything about clinical practice." The article itself concluded, "Whether ECG should be incorporated in routine screening of older adults should be evaluated in randomized, controlled trials."

In the same edition of JAMA a Northwestern University Preventive Medicine professor, Dr. Philip Greenland, commenting on Auer's research, mentioned a 1989 summary of the value of the "resting ECG," which said additional study was needed. Dr.Greenland said the major finding in Auer's work was a relatively new measurement called the net reclassification index (NRI). As opposed to diagnostic studies (e.g., does this patient have heart disease), this study hoped to be prognostic, telling what the chances were of a major heart event occurring in the future to a particular study subject. In this case the NRI helped most in reclassifying people into a lower CHD risk group, not a higher one.

All of that is fascinating and the Auer article is a superb example of carefully performed research. But, my fear is that many physicians won't read the caveats. If you ignore the last paragraph, skip the editorial and never get to "'s" take on the work, you may well decide that every older adult should have an ECG done on a regular basis.

What should we do if your cholesterol is high?

In the same edition of the journal is a pair of short articles deliberately set up to examine a medical controversy, in this case whether a middle-aged man with an elevated cholesterol, but no personal or family history of coronary heart disease should be given statin drugs to lower his cholesterol. This is a new feature of the journal, and the accompanying editorial, with the intriguing title, "The Debut of Dueling Viewpoints," explains this will be a continuing series of discussions and debates.

What a wonderful idea.





The the online publication, actually had a nice summary of the two pieces,

Medical Waste: Part one

Thursday, April 12th, 2012

health care costs are making news and setting records

Whenever I think of medical waste I flash back to the episode (It's in one of my old blog posts) with my Radiation Safety Officer standing on a pile of garbage in a municipal dump in Biloxi, MS, holding a Coke bottle that set off a radiation detector. It had tobacco juice spat by a patient who'd had a thyroid scan.

But that's not what I'm writing about today.

There's a great article in the most recent edition of JAMA with the title "Eliminating Waste in US Health Care."  In July, 2010, Dr. Donald Berwick, the lead author, was appointed by President Obama to serve as the Administrator of the Centers for Medicare and Medicaid Services. This was a "recess appointment" of a Harvard Medical School professor of pediatrics with a Master of Public Policy degree who had previously led the non-profit Institute for Healthcare Improvement. Congress did not confirm Berwick (ah, politics, isn't it wonderful) and he left  the position in December, 2011.

Berwick and a colleague at the RAND Corporation. a non-profit with goals of improving both decision-making and public policy by utilizing research and analysis, start by stating our health care costs are frankly not sustainable and yet are growing with 2020 estimates of 20% of our gross domestic product (GDP).

Between 1980 and 2008, our US health care costs, as a share of GDP grew phenomenally. The Kaiser Foundation has an online comparison of health care expenditures in the US and 14 other OECD countries. We not only spend more on health care, our per person growth rate of this expenditure is among the highest in the developed world. Let's put that into concrete terms. The Kaiser paper shows a graph of total health care spending per person versus gross domestic product per person and locates where 15 of the world's developed countries fall in comparing those two variables.

The dots representing thirteen of the countries form a line with Italy having the last spending and the least average "income" per person and Switzerland having the top amounts of that group in both categories. Then there's Norway and the United States, both well off the line. The average Norwegian income is considerably higher than the US average, but the average amount spend on all their health care is way below the line, while ours is far above that same line.

These were 2008 figures, but the major difference was shown in growth of the total spent on health care per person per year and the source of that money. In Norway's case, the bulk is public spending and in ours it is split between public and private. And our growth in both categories tops the pack.

It's time to look at all the ways to solve the puzzle

Dr. Berkwick's article in JAMA details how much we could potentially save with six strategies to reduce "medical waste." The total is staggering: $3 trillion in Medicare and Medicaid savings and $11 trillion overall by 2020. He contrasts this to the savings proposed in the Affordable Healthcare Act of $670 billion between 2011 and 2019, no paltry sum by any means, but dwarfed by the common sense proposals he makes.

And nobody loses by our taking a very close look at his concepts.



Chocolate, Part Two: the French paradox, free radicals and flavonoids

Monday, April 2nd, 2012

I need his size of brain to take in all the background material

I wanted to examine the possible health benefits of chocolate further and found myself immersed in nutritional and biochemical articles. So now I've slogged though eight different sources, ranging from a University of Mumbai review of health benefits of some of the chemicals in chocolate (and green tea, onions, red wine and apples) to three nutrition journals, a WebMD piece on antioxidants and a Harvard School of Public Health article titled, "Antioxidants: Beyond the Hype."

There's a concept known as the French paradox, first popularized in a 1991 segment on CBS's show, "Sixty Minutes." The French eat chocolate and cheeses and drink red wine, yet  their obesity rate is the lowest in Europe, and although they smoke and eat a moderately high-fat diet their cardiovascular death is also fairly low. Those statistics are worsening as the invasion of the Western Diet spreads through the country, but they still hold true.

Let's concentrate on chocolate for now and I'll return to that paradox some other time

In simplest terms I think of atoms as being like tiny solar systems with a sun (the nucleus) in the middle and "planets," electrons circling around. The center has relatively large particles with no charge (neutrons) and positive electrical charges (protons); the shells have tiny particles with negative charges (electrons). The latter are not just arranged in orbits like planets; a closer analogy would be Russian Nesting Dolls.

When you eat, your body uses glucose for fuel. In doing so it produces some extremely harmful molecules called free radicals. These are atoms with an electron missing and they try to regain electrical balance by stealing negatively charged particles from other atoms. You can also pick up free radicals from air, food or sunlight's effect on your skin. They can harm your DNA, cause "bad cholesterol' to get stuck in the wall of a blood vessel, or speed up the aging process of your skin.

We do have some defences against those nasty free radicals and they're called antioxidants. A variety of studies done on these chemical weapons have yielded inconclusive results, but one long-term study, part of the Physicians Health Study, appeared to show a significant benefit in cognitive function and another showed a decrease in the risk of heart attacks in men aged 50 or older.

Even these mixed results led to a huge antioxidant supplement industry with sales estimated over $500 million a year.

another antioxidant source

We're much better off, many think, consuming natural sources, especially fruits and vegetables and red wine (not beer or white wine).

And now there's chocolate. Dark, bitter chocolate appears to lower blood pressure, improve blood flow and improve insulin sensitivity. Dean Ornish's Newsweek  article, mentioned in my last post, says there's four times as much cocoa flavonoids per serving than in red wine or tea.

I asked my wife to buy some dark chocolate and ate a half a bar last night and the other half tonight. I ate it slowly, savored each taste and put the half remaining in the refrigerator last evening.
I plan to buy more tomorrow.


Chocolate: a new medicine? Part One

Tuesday, March 27th, 2012

Dark chocolate, in small amounts, is good for youI was reading The Wall Street Journal this morning and came across an article titled "A Chocolate a Day to Get Slimmer?" I'm not a major chocolate eater, but had heard something on NPR about this study yesterday, so ate eight small pieces of dark chocolate at a board meeting last evening. Then, when I weighed myself before breakfast today, I realized I was down 2.8 pounds.

Should I continue this increased chocolate consumption or was that, as I of course knew, just "water weight" I'd lost? The previous night I'd eaten a prolonged meal with friends at our favorite Thai restaurant and the next morning had gained over three pounds.

Let me digress a bit. Whenever I mention water weight I'm really referring to fluid that the body keeps because of dietary salt excess. I normally don't use table salt, as I have a family history of high blood pressure and was aware that most of us, eating a typical American diet, were ingesting far too much sodium, the crucial element in table salt. When I eat out I expect my weight to bounce up a few pounds and don't worry about that short-term increase. The salt in the food causes me to retain fluid and therefore to gain weight temporarily. Many diet plans that advertise losing five or more pounds in the first week are really helping people get rid of water weight.

Okay, back to chocolate. The article I mentioned is important, but the message it's carrying is nothing new. In 1973 I saw Woody Allen's movie, "Sleeper" in which he plays a nerdish store owner who is revived out of cryostasis (a form of preservation using ultra-cold temperatures) after 200 years. In that future world science has shown chocolate to be good for you.

Two prominent food gurus, Andrew Weil and Den Ornish, mention health benefits of chocolate. I found Dr. Ornish's 2007 Newsweek article,"Chocolate to Live For," in which he mentions a host of medical studies showing dark chocolate, which has higher amounts of beneficial chemicals called flavinoids, may lower blood pressure and and improve blood flow to your brain and heart. White chocolate and milk chocolate have very small amounts of flavinoids and bitter dark chocolate has the most.

Eat a small bite of dark chocolate and meditate

The phrase "moderation in all things" dates back more than two thousand years to a Roman "comic dramatist." It certainly applies here. None of the articles I read were about eating a lot of extra calories in the form of chocolate. Dr. Ornish's approach made sense to me; he very slowly eats a bite of dark chocolate, meditates while doing so by focusing on the experience with all of his senses, and regards the very first bite as being the most pleasurable.

What a great way to eat something he regards as a special treat as well as a health food.

I've never tried that with chocolate, but having read his magazine piece, I'll try that approach.

I'll continue with more medical background on chocolate in my next post, but to whet your appetite will give you a link to today's article in WSJ.

Happy chocolating.




Toxins for tots and the rest of us too: part one

Saturday, March 24th, 2012

This speaks for itself

All of us are exposed to potentially dangerous substances in many of our household products, but there's been increasing concern that pregnant women need to pay special attention to  the ever-growing list of chemicals around the home. I just read an article published in The New York Times nine days ago with the gripping title "Is It Safe to Play Yet?" The subtitle described what's going on in many families: "Going to Extreme Lengths to Purge Household Toxins."

I found a reference to an extraordinary study which examined umbilical cord blood samples drawn from ten infants of minority heritage: African-American, Asian or Hispanic. Five independent laboratories were involved and up to 232 toxic chemicals were found. I was familiar with the Environmental Working Group, one of the two non-profits who commissioned the research, but not with Rachel's Network which I found online. It's a women's organization named in honor of Rachel Carson whose book, Silent Spring, in many aspects launched the modern environmental movement.

EWG had been unable to find any published studies focused on minority group infants, yet some of their homes are more likely to be situated near busy highways and roads, to be closer to industrial shops and factories and to have been built before current safety standards were established.

Other studies have found up to 358 chemicals in cord blood of US infants; some are acknowledged as possible cancer-causing agents, nervous-system toxins or endocrine hormone disrupters. The National Institute of Environmental Health Sciences (NIEHS), part of NIH, says those latter toxins can be found in metal food cans, plastic bottles, food, toys, cosmetics, detergents, pesticides and flame retardants. Their adverse effects have increased potential to harm fetuses and young babies as their bodies develop.

asbestos can cause mesothelioma, a rare cancer usually of the lining of the lungs and chest cavity

Our Toxic Substances Control Act, is a 1976 law that, unfortunately, grandfathered most existing chemicals. The Environmental Protection Agency (EPA) was mandated to protect the public by regulating the manufacture and sale of chemicals But 60,000 chemicals were excluded because they were already in use and over the following years the EPA succeeded in restricting only five of those: one was asbestos, but two years after the chemical was banned the rule was overturned by the Fifth Circuit Court as being too broad.

In contrast, the European Union, in 2007, passed REACH, the Registration, Evaluation, Authorisation and Restriction of Chemicals act that applies to all chemical substances; not only those used in industrial processes but also in day-to-day lives, for example in cleaning products, paints as well as in articles such as clothes, furniture and electrical appliances.

REACH places the burden of proof on companies. To comply with the regulation, companies must identify and manage the risks linked to the substances they manufacture and market in the EU. They have to demonstrate to a governmental agency how the substance can be safely used, and they must communicate those risk management measures to the users.

One estimate, published in Health Affairs in 2011, estimated the US spends $76.6 billion a year on kids' medical issues that may be related to their environment.

We have a long ways to go, both in determining which chemicals are actually risky and banning or controlling their use.

And, on the other hand, knowing which chemicals, old and new, are safe for us and our offspring.