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Health effects of long term pollutant exposure – A known unknown?: Part II

Posted on June 14th, 2011 by Alf | No Comments | Print | RSS

In Part I of this blog, we looked at the possible health effects of environmental pollutants. In the conclusion we will look at their unexpected and unpredictable effects.

There is also no doubt some of the environmental chemicals we are exposed to in our every day lives are harmful if taken in large enough amounts. Certainly, many of the pesticides, metals such as arsenic, lead and mercury and a great number of the industrial waste products are considered toxic. Yet governments believe in the amounts we are exposed to, they do not pose a risk to our health. The main reason for this – and this applies to most environmental chemicals – is the amounts finding their way into our bodies are so minute it is difficult to see how they can be harmful. Unfortunately, it may not be this simple. There is plenty of evidence – from reputable medical and scientific sources – to show tiny amounts of enviromental chemicals and pollutants can produce quite unexpected effects. A good example is the well known herbicide, glyphosate – commonly called Roundup®. At the amounts suggested by the manufacturers, it is highly toxic to broad leaf plants but apparently safe to humans. But a surprisingly different effect has been observed at concentrations much lower than those required to kill weeds. At these tiny non-toxic doses, like those generated by the drift of glyphosate spray from neighbouring farms, the herbicide may actually stimulate growth of certain plants (7). Another example is the antioxidant resveratrol, present in food and abundant in red wine. Its presence in red wine is thought by some to explain the “French paradox” – ie the apparently low incidence of heart disease in the French despite a relatively high intake of butter and cream. At higher concentrations, resveratrol can kill a variety of different cancer cells. This is the good news. However, the bad news is at much lower doses, the antioxidant may actually stimulate tumour growth, at least in the test tube (8).

So, these examples show we cannot always predict what a chemical substance will do at very low concentrations. Some scientists refer to this phenomenon as “hormesis”(8). While there was initially a fair amount of skepticism amongst scientists over this, there is increasing acceptance there is a degree of unpredictability about how chemicals can affect biological systems at low concentrations. Indeed, this unpredictability is a good example of what Donald Rumsfeld, the former US Defence Secretary termed “a known unknowns” in his now infamous press briefing of February 12, 2002.

But wait: It’s even more complicated than this! Read the rest of this entry »

Health effects of long term pollutant exposure – A known unknown?: Part I

Posted on May 24th, 2011 by Alf | No Comments | Print | RSS

In his 1973 book, “Small is Beautiful: A Study of Economics As If People Mattered”, the German born economist E. F. Schumacher stated:

“No degree of prosperity could justify the accumulation of large amounts of highly toxic substances which nobody knows how to make “safe” and which remain an incalculable danger to the whole of creation….”

The “substances” Schumacher was referring to were the radioactive waste products generated by the nuclear power industry. We will discuss the nuclear power industry and the background and implications of the full Schumacher quote at another time. Nevertheless, this quote equally applies to the great number of highly toxic chemical pollutants realeased into the environment on a daily basis through human activities. And as they have also not been “made safe” before release, they pose a potential threat to our health and wellbeing. Rather than accepting responsibility for cleaning up our messes, we either rely on nature to make them “safe” for us or hope we are diluting them enough to make them safe by dumping them into something as large as a river or ocean: The “Dilution is the solution to pollution” approach. Certainly, many of the toxic chemicals from industrial and agricultural waste products are gradually degraded into less toxic materials by nature, either through chemical processes, like heat, light and UV radiation, or through the action of microorganisms in the soil or water. But is it really this simple? Read the rest of this entry »

Fukushima – A Warning

Posted on May 2nd, 2011 by Stephen Hardy | No Comments | Print | RSS

The 9.0 magnitude earthquake and tsunami that hit Japan on March 11, 2011 was a disaster on an unprecedented scale. Nightly the news showed images that looked like they had come from a Hollywood disaster movie. But these images were real, affecting real people and devastating real lives.

Japan is a proud and resilient nation. They will rebuild; they have done it before. In time and with human effort and commitment, life will return to normal. Or will it? The earthquake and tsunami of March 11 is fundamentally different to any disaster Japan has suffered before. It is fundamentally different because none of the previous disasters caused a leak in a nuclear power plant, releasing radiation to contaminate the environment. As a result, there may well be large parts of Japan where life can never return, let alone return to normal.

I won’t discuss the wisdom of building nuclear reactors on the coast of an earthquake and tsunami prone country or whether we should embrace uranium and plutonium to satisfy our growing lust for energy. I’ll leave that topic for another time. What I want to talk about today is what the radioactive material leaking from the damaged Fukushima reactors means for living systems and public health. And I also want to talk about the mixed or downright misleading information coming from the mass media. Read the rest of this entry »

Is it really organic?

Posted on April 14th, 2011 by Alf | No Comments | Print | RSS

I like walnut bread. Freshly made, straight out of the oven, with a hint of sweetness from the added honey and the crunchy texture of walnuts from my very own walnut tree, it really is hard to beat. (I have included my recipe for walnut bread at the end of this blog). As happens, I had run out of organic flour, so trundled down to the local health food shop to buy more. My local shop has recently begun stocking flour they called “organic”. And there it was – in a large plastic bin complete with a label proudly advising consumers that it was organic. I looked closely at the label showing the fat, protein, and carbohydrate contents. However, there was nothing on the label to say who had certified the flour was organic or where it had come from. When I asked the sales assistant to tell me who the organic certifier was, I was met with a blank expression signifying – I think – that she did not know what I was talking about. When I explained that, as a consumer, I was entitled to ask who the certifying body was, I was told I was being difficult, and was “giving her a hard time”. All because I asked for something that is standard practice for retailers of organic food!

My recent experience was not unusual. The very same day I went into a self-proclaimed “organic shop” to buy some organic vegetables (by the way, it is worth mentioning that just because a it calls itself an “organic shop” does not mean that everything it sells is organic). There were lots of “organic” fruits and vegetables to choose from, with prices that apparently reflected this (double or more the non-organic price). Once again there was an absence of certification details for much of the produce. In view of my earlier experience, I weighed up whether to risk confrontation with the shop owner and decided against asking them for the certification information and walked out of the shop. It further illustrated the consumer has to be quite assertive when shopping for organic food. But why should they have to be? Read the rest of this entry »

Looking backward to go forward

Posted on March 15th, 2011 by Stephen Hardy | No Comments | Print | RSS

My father died recently at 99. Needless to say, it causes you to reflect. Dad was a Doctor – a pathologist. As a student, his job at University was to look after the medicinal leeches. He saw the introduction of the sulfur drugs in the 1930’s, the first drugs in human history to effectively fight infectious diseases. Yet within 10 years, penicillin – the first true antibiotic – became widely available, rendering the sulfur drugs all but obsolete. He marvelled at the revolution in pesticides, pharmaceuticals, plastics and agri-chemicals that occurred after World War II. Took part in the British nuclear tests at Maralinga. Saw the wonders of heart, kidney, liver and lung transplants. And as his career drew to a close, the magic of genetic engineering and the ability to manipulate DNA – the very building blocks of life. Born just 8 years after the Wright brothers first flight, he saw the sound barrier broken, Neil Armstrong leave his footprints in the lunar dust and the Voyager spacecraft send back high-resolution images from Jupiter, Saturn, Uranus and Neptune. Over the course of his life the world’s human population grew from 1.7 billion to 6.8 billion to become the dominant life form on the planet. In one human lifetime – my father’s lifetime – humanity has moved from being at the mercy of nature to being a force of nature, free to shape and control the world. Read the rest of this entry »

What are we adding to our food?

Posted on February 22nd, 2011 by Alf | No Comments | Print | RSS

Just a cursory glance at supermarket shelves and refrigerators cabinets will attest to the staggering variety of food available to consumers. While supermarkets do sell fresh food, like fruit and vegetables, most of the food sold in supermarkets is treated or processed in some way. Even the contents of a humble carton of milk, to all intents and purposes a “fresh” product, are not what has come out of a cow. FIrst, the milk has been heated briefly to high temperatures (pasteurized) or even higher temperatures for UHT milk and homogenized, to distribute the cream and fatty components throughout the milk. In some cases all or some of the fat may have been removed (skim milk and low fat milk respectively), or it has undergone treatment to remove the milk sugar lactose (lactose free milk), or it has been fortified in some way by adding nutrients such as extra calcium, vitamin D or even fish oils. These treatments are relatively minor (although this may be disputed by those opposed to pasteurization and homogenization), when compared to some other ways we treat our food. The conversion of a simple grain of rice into a well known breakfast cereal, or the extraction, deodorization and bleaching of oil extracted from seeds, a two very good examples but there are many more. Read the rest of this entry »

Krill oil: Taking the long term view

Posted on February 8th, 2011 by Alf | No Comments | Print | RSS

In two earlier blogs on fish oil supplements, I wrote about the lack of convincing evidence for some of the claims made about fish oils. We have discussed the evidence for and against the benefits of fish oils in great detail in our eBook: “Fish Oils – Everything You Want To Know” – available through this website. There is no doubt omega-3 fats, (specifically EPA and DHA), believed to be responsible for the beneficial effects of fish oils, are essential for the normal function of many of our organs, particularly the brain and retina. However, in some quarters, fish oils have been increasingly portrayed as a cure or treatment for almost everything. I have always been very skeptical of anything that is put forward as a universal cure or treatment. Nature just doesn’t work that way. And I am not alone in this, with others describing fish oils as the “Emperor’s New Pills” (1).

The fatty components of fish have uses other than as nutritional supplements. In this blog I want to talk about their use in the rapidly growing area of aquaculture.

Aquaculture is now a large international industry. The 2010 State of the World Fisheries and Aquaculture report by the Food and Agriculture Organization of the United Nations (FAO) illustrates this point very well. The FAO concluded that of the worlds wild fish stocks:

28% were overexploited;
8% were depleted;
and 52% were already fully exploited (2).

The report goes on to say that the top 10 species of fish comprising 30% of the world market are already overexploited. While these figures were for 2007, it is unlikely the situation will have improved since. With the world population due to reach 7 billion fairly soon and the rise of large and affluent middle classes in China, India and other parts of the developing world, one would expect the situation to get a lot worse. Read the rest of this entry »

What are environmental chemicals doing in breast milk?

Posted on January 19th, 2011 by Alf | No Comments | Print | RSS

What is free, cheap, non-processed, fresh, highly nutritious, perfect for babies, and readily available? Well, there are no prizes for guessing the answer is breast milk. It truly is a wonder food. Around 1% protein, 4% fat (including the omega-3 fats), 7% carbohydrate, minerals and vitamins all in a readily available form. Not only does it have all of the nutrients that are required for growth, it also contains factors that protect infants from infection and help educate the babies immune system.

The composition of breast milk can vary significantly from woman to woman. One important factor in this variability is the diet of the mother. For example, the fat composition of the breast milk is dependent on the types of fats in the mother’s diet. So, if the mother’s diet is rich in the special omega-3 fats in fish, or takes fish oils during lactation, the levels of these fats increase in the milk. Conversely, if the mother’s diet is deficient in vitamin A, an important nutrient, her breast milk may contain insufficient amounts of the vitamin to ensure optimal growth and development of her baby (1).

So, what is present or missing in the diet of the mother can affect the composition of their breast milk and in turn, have an impact on the health of the baby. Unfortunately, there are other substances often present in the maternal diet which are not normal components of food but are either contaminants in food, or deliberately added to food at some point. There are also many pollutants that can enter the mother’s body in other ways – for example through environmental exposure, skin contact, or through the lungs. Examples of contaminants detected in food include the pesticides used to control pests both before and after harvest, plastics components such as phthalates and Bisphenol A (BPA) and industrial waste products. The latter include the polychlorinated hydrocarbons (or PCBs), the polybrominated hydrocarbons (PBDEs), and heavy metals such as mercury. There are literally thousands of other substances we are exposed to in our daily lives and theoretically at least, many of these can be taken up. Read the rest of this entry »

Food Labelling – A consumer minefield?

Posted on January 5th, 2011 by Alf | No Comments | Print | RSS

If Rip Van Winkle, waking up after his 20 year sleep, wandered into a 21st century supermarket he would be astounded at the range and diversity of goods, the colorful packaging, and the staggering choice available to the consumer. He would gaze uncomprehendingly at the labeling with its kilojoules or calories, serve size, list of additives etc. While there is now a degree of public awareness of many of the terms used on labels, the whole area is quite literally, a minefield. Part of the problem is what is on labels serves at least two separate functions – to inform the consumer so they are better able to make a choice, and to entice the consumer into buying a particular product in preference to another. These two conflicting interests understandably create some difficulties for consumers. Read the rest of this entry »

Water, water everywhere but how safe is it to drink?

Posted on December 19th, 2010 by Alf | No Comments | Print | RSS

It is hard to believe, particularly for people coming from dry and drought-ravaged regions of the planet (like our state of South Australia), that water covers more than 70% of the Earth’s crust. It is also the largest component of the human body, averaging around 60% of the body weight of an adult male although the proportion is even higher in a 20-25 week foetus (greater than 80%). All of our organs contain large amounts of water, and the myriad chemical reactions occurring in billions of cells in these organs taking place in an aqueous medium. The blood that carries nutrients to the different parts of our bodies is mainly water, and our waste products are dissolved in water ie urine. Just about everything we eat contains large amounts of water, and many of us drink a litre of more of water a day. So, however you look at it, water is central to our life.

Unfortunately, while we can’t do without water, the same applies to every other living thing on the planet, including bacteria, fungi, and parasites. Some of these grow and thrive in water, including bacteria that cause cholera and other diseases. Another property of water is its almost unique ability to dissolve all sorts of substances. Its ability to dissolve gases such as oxygen is absolutely fundamental to the survival of fish in the sea and rivers. Similarly, carbon dioxide dissolved in water is essential for the survival of algae and other plant life that live in the oceans, rivers and lakes.

But, of course, it is not just gases that dissolve in water. The oceans contain large amounts of salts as well as many other materials while the rivers, a major source of drinking water for many people, contain all manner of dissolved salts as well as sediment derived from rocks and soil. Fertilizers, animal wastes, composts, pesticides, industrial waste, pharmaceuticals, antibiotics used in animal feeds, plastic components, and air pollutants all find their way into rivers and, eventually, into the ocean. Traces of some of these materials, termed “organic matter” because the molecules it contains, are mostly made up of carbon atoms, may be present in our drinking water. The amount of this organic material in our drinking water is not insignificant because levels approaching, or even exceeding, 4 milligrams per liter are not unusual. This means that, over a fifty year period, and assuming we drink one litre (around 1.6 pints) per day, we take in over 70 grams (2.5 ozs) of this material. Read the rest of this entry »