Archive for the ‘childhood diseases’ Category

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.

Don't vacillate, vaccinate instead!

Wednesday, March 21st, 2012

Could she have measles?

The Wall Street Journal this morning had an article titled, "Where Could The Next Outbreak Of Measles Be?" A secondary heading on a later page said, "Low Vaccination Rates Trigger Fears," and there was a US map showing problem areas. Boulder, Colorado was one of those hot spots.

The article led me back to the concept of "herd immunity," very well illustrated on a webpage from the National Institute of Allergy and Infectious Diseases. Basically it says we need a relatively high percentage of a given population to be vaccinated (AKA immunized) against a given disease in order to prevent epidemics.

The particular viral disease I'm writing about is measles, sometimes called "red measles" or, technically, rubeola. The National Library of Medicine has an excellent, brief description of this ailment and notes that before widespread vaccination became common, most people had a case of measles before age 20.

Then the MMR vaccine was developed by a Merck scientist in the 1960s. Measles incidence went from being, as a 1954 quote termed it, "as inevitable as death and taxes," to an uncommon to rare disease in developed countries. In the US for the twenty years after the vaccine was licensed, an estimated 52 million overall cases, 17,400 leading to mental retardation and 5,200 deaths were prevented.

In 2000 the WHO estimated that there were still ~45 million cases of measles worldwide yearly causing 800,000 deaths. While mortality in developed countries was ~1/1000, in sub-Saharan Africa, mortality was 10%. In cases with complications, the rate could rise to 20–30%. On average, ~450 children died every day from measles. By 2007 immunizations had cut the yearly global death rate by 75%.

But in 1998 an article in The Lancet had caused a stir that has continued to this day. A British gastroenterologist reported a series of 12 young patients who were referred to his practice with bowel complaints. Their average age was six and 8 of them developed symptoms of autism within a month after they got their MMR injection.

Should I believe what I just read?

Many parents hearing about this report stopped their children's immunizations. This was in spite of numerous much larger studies showing no connection between MMR and autism. In 2005 a Japanese group showed an increase in autism diagnoses in children who got their childhood immunizations after the country's particular MMR vaccine was withdrawn from use because of a suspected side effect of the mumps component. In 2009 a review of multiple large studies was published examining three linkages that had been proposed: MMR and autism, thiomerosal (a mercury-based preservative chemical used in some vaccines, but not in MMR) and autism, multiple vaccinations and autism.

The accumulated data from these large groups in a number of countries showed no association between any of these factors and autism. Finally in 2010 The Lancet published a rather wishy-washy retraction of the Wakefield article.  His license had been revoked by the UK General Medical Council and the British Medical Journal's editorial staff published a much stronger condemnation of Wakefield's work in 2011, calling it fraudulent.

And yet today's WSJ article note parts of the US, especially in the northwest, have relatively poor compliance rates with vaccination guidelines. Parents can opt out because of medical, religious or even philosophical concerns. Low-income kids can receive free immunizations under a federally-funded programs, but one physician interviewed said the parents in his practice who don't want their kids vaccinated are wealthy and well-educated.

We've seen some minor outbreaks in the past few years. If we don't overcome parental misinformation and fears, we may have a major epidemic.