Announcer

Plastics will play as large a role in peace as they do in war.

NARRATION

The 20th century gave rise to the chemical industry. It has revolutionised our world and transformed the way we live.

Laureate Professor John Aitken

After the Second World War, there was a sudden burst of activity in the chemicals industry and the environment has become flooded with new chemicals.

NARRATION

Over 80,000 chemicals are used in everyday products. We handle them, they're in our water, our food and in the air we breathe. It's impossible to escape them. But now there's growing concern that these chemicals are not safe.

Professor Peter Sly

There's no requirement to show that these chemicals are actually safe before people are exposed to them.

Dr Linda Birnbaum

We basically, in the US, consider chemicals safe until proven otherwise.

NARRATION

Experts believe the rise in the use of industrial chemicals is linked to issues like lower IQ, cancer and reproductive problems.

Dr Maryanne Demasi

So, without adequate testing of the safety of chemicals, are we in the midst of an uncontrolled human experiment?

NARRATION

Chemical pollution begins in the womb. From the moment we're conceived, our bodies are exposed to a cocktail of potential toxicants.

Laureate Professor John Aitken

Mothers are being exposed to chemicals during pregnancy. These chemicals are somehow finding their way across the placenta directly into the foetus and having an impact on the normal pattern of development.

NARRATION

The dangers of chemicals, like mercury and lead, have been well established. But less is known about other chemicals which interfere, or perturb, with our endocrine system. This system of glands produces hormones that regulate virtually every aspect of human health, beginning at our most vulnerable time in the womb.

Dr Linda Birnbaum

Our hormone system controls who we are. It controls our basic physiology as adults, but our endocrine system is absolutely essential during development.

Professor Peter Sly

Timing is actually critical. There's this concept of windows of susceptibility where an agent can have really adverse effects if it's present at a specific time during development. For example, something can cause an adverse effect if it's exposed on day 18 but not if it's exposed on day 20. It can be that critical.

Dr Linda Birnbaum

It's like you throw a monkey wrench into a system and it can never recover from it. So you'll have permanent change.

NARRATION

In plastics and in the lining of cans, you'll find bisphenol A, or BPA. In cosmetics, skin creams and perfumes there's phthalates. Foods sprayed with pesticides. Carpets, furniture and electronics, all infused with fire retardants. It's the chemical soup of modern life. The concern is our bodies mistake them for hormones.

Dr Andrea Gore

Endocrine-disrupting chemicals can act like hormones or they can interfere with hormones. And if there's any perturbation, including an extremely small perturbation, due to a deficiency in a hormone, an excess of a hormone or some sort of outside chemical, like an endocrine disruptor, that can have very devastating consequences.

NARRATION

One of the most researched chemicals found in plastics is BPA, which mimics the female hormone oestrogen.

Professor Ian Shaw

This is the oestrogen molecule and it binds to the oestrogen receptor, rather like a lock and key. Switches on the receptor and carries out the oestrogenic properties. BPA, the molecule below here, you can see has a very similar sort of structure. And if you superimpose them on top of each other, you can see the hydroxyl groups line up really nicely. So that will be a key for the lock.

Dr Maryanne Demasi

So it's quite possible that BPA would have very similar effects to oestrogen when it binds?

Professor Ian Shaw

They will have almost identical effects. The only difference will be the magnitude of the effects for BPA are lower than oestrogen, because it doesn't fit that receptor quite as well.

NARRATION

The supply of oestrogen to a foetus is exquisitely controlled by the placenta in order to achieve normal male and female development.

Professor Peter Sly

The placenta itself detoxifies the oestrogens from the mother, the natural oestrogens, and stops them crossing into the foetus. Unfortunately, some of these synthetic chemicals, and particularly things like bisphenol A, while they have endocrine and oestrogen activity, they're not recognised by those detoxification enzymes as oestrogens and they pass straight through the placenta.

NARRATION

Scientist were first alerted to the potential effects of endocrine disruptors in wildlife species.

Laureate Professor John Aitken

Fish in the rivers of the south-east of England, where 85% of the water flowing through those rivers is recycled sewage water, contains high levels of oestrogenic compounds and it was influencing the sexual differentiation of the fish. There's been similar data in Lake Apopka in Florida, where alligators have been found which have abnormalities of penile development, normal sexual development, which has been correlated with chemical spills into that lake beforehand.

NARRATION

This was the result of high-dose exposures where the impact on health is obvious. But establishing such chemical links to human health is harder.

Dr Maryanne Demasi

The link between chemicals and human disease is based largely on correlations. So it doesn't prove causation. That's why scientists have to rely on animal studies to support their hypotheses.

Professor Ian Shaw

The research in animals is really very important indeed to try and get cause and effect. If you look at some of the early studies in animals, for example, if you give a rat in development an endocrine disruptor and it's a male we're looking at, you often get changes in the development of the penis. So if you give oestrogenic compounds during the development of that rat, then you will affect the penis. And that's a really good example of cause and effect. Whereas the studies in humans are looking levels of chemicals we're exposed to and effects. We never quite know whether they're linked.

NARRATION

And that's the challenge - to prove the effects in animals also occurs in humans.

Dr Linda Birnbaum

There's something that's been termed the testicular dysgenesis syndrome, and this includes things like hypospadias, which is where the urethra does not exit at the tip of the penis. It's cryptorchidism, or otherwise known as undescended testicles, which cause sterility. There is low sperm count or impacts on sperm quality, mobility and so on, and there's also testicular cancer.

NARRATION

In the past 30 years, the incidence of testicular cancer in Australia has increased by over 50%.

Laureate Professor John Aitken

It's undeniable that this increase in testicular cancer is occurring. It's too vast to be entirely genetic and, therefore, likely to be something which is environmental.

NARRATION

Most men are diagnosed at around age 30. But the initial cause can be traced back to the womb.

Laureate Professor John Aitken

Testes development is a very sensitive barometer of environmental toxicants. When these environmental chemicals hit the testes, there are some cells sitting in the testes that are of a very primitive kind. And they respond very abnormally to that signal and give you your testicular cancer.

NARRATION

In some countries, up to 40% of young men have poor semen quality. The link to toxicants is inconclusive but certainly plausible.

Laureate Professor John Aitken

Spermatozoa are just very susceptible to attack by chemicals and the reason for that is very evident. If you just look at them, they're composed of nothing more than basically a nucleus on top of a sperm tail. There's no space in there to put any protective enzymes that are going to help preserve the integrity of these cells.

Dr Maryanne Demasi

But haven't we developed mechanisms to be able to deal with these kinds of toxins?

Laureate Professor John Aitken

In the last century or so we've introduced a whole new range of toxicants into the environment for which our defence mechanisms are not well adapted. And it's probably that lack of fit between our defence mechanisms and these new chemicals that have arrived in the environment that are responsible for these impacts that we're seeing on reproductive health.

NARRATION

The Endocrine Society, representing over 18,000 members, set out to update all the scientific evidence linking chemicals and endocrine-related disorders. Toxicologist at the University of Texas, Andrea Gore, spearheaded the report.

Dr Andrea Gore

We knew that there were increases in infertility, there were disorders of puberty. People were noticing their girls were going through puberty at nine and ten years old instead of 11, 12 or 13 years old, which is when they used to go through puberty. And the Society began to wonder, and the endocrinologists began to wonder, whether there were chemicals in the environment that may be responsible for that change.

Professor Ian Shaw

The way that puberty is stimulated in girls is for a quick shot of oestrogen, which the girl begins to produce just before she goes into puberty. So if that girl is exposed to a hormone mimic, and oestrogen mimic and endocrine disruptor, that might well start the process. If you give rats a dose of oestrogenic chemicals, endocrine disruptors that mimic the female hormone, they will also come into puberty earlier. So in animal studies the connection is absolute, in human studies it's not absolute, but the two things are together. The dose is crucially important for any toxicological consideration. Hormones work at an infinitesimally tiny doses, and oestrogenic chemicals work at infinitesimally tiny doses. So the sort of doses that you get in water and food, contamination from plasticisers or whatever, are well within the range of doses to have a biological effect.

NARRATION

Canadian researcher Dr Bruce Lanphear says even low levels of chemicals can have a significant impact on brain development.

Dr Bruce Lanphear

In many of the chemicals that we're concerned about, like flame retardants, like lead, seem to be dopaminergic toxicants. They seem to disrupt the prefrontal cortex, that part of the brain that makes us most distinctly human. So that's particularly concerning to us is when you start to monkey with that, that's the part of the brain that allows us to think fast on our feet, to be a CEO, to be a scientist, to have impulse control. And so if we start messing around with that, we're really dealing with a part of the brain that makes us human.

NARRATION

US data shows exposure to endocrine disruptors was also associated with a five-point decrement in IQ.

Dr Bruce Lanphear

When we see this on a population level, impact is phenomenal. So take in the United States, if you shift the mean IQ by about five points, that results in an increase in the number of kids who are considered challenged - what we used to call mentally retarded - from about six million children to over nine million children.

NARRATION

There's also a corresponding decrease of 2.4 million gifted children with high IQs.

Dr Bruce Lanphear

So when you start to look at the impact of that, it's huge. What we're beginning to recognise, those of us that do this work, is that the pattern is pretty clear. We should expect that some of these chemicals will be toxic and we should no longer be using our children as guinea pigs to find out when they are toxic.

NARRATION

Some chemicals are stored in the body for decades, whereas others are metabolised and excreted readily.

Dr Linda Birnbaum

We have some chemicals, like the persistent organic chemicals, which tend to build up in your body over time. But there are other chemicals which have very, very short half-lives, and they are handled by the enzyme systems in our bodies. But at the same point, that doesn't mean we aren't exposed again and again and again and again. And we begin to see that even short-lived chemicals can have effects.

NARRATION

International media has shown a spotlight on the safety concerns of one of these short-lived chemicals - BPA, which is known to leach out of plastic into food and drink products.

Bonnie Searle

I'd heard some reports in the media. So when I was pregnant, I was even more careful with the plastics I was using with my food. If I'd had a takeaway in a plastic container, I'd make sure that wasn't reused 'cause the food would've been hot. Leftovers in glass dishes rather than plastic when I was storing them. I think, from a consumer perspective, it's confusing 'cause it hasn't been confirmed if BPA is harmful. It's not always labelled on the plastic. We don't know what other chemicals are also in the plastic that haven't been researched. We just don't know enough yet.

Professor Peter Sly

We don't necessarily know about the chemicals we're exposed to because there's no requirement on manufacturers to list all the ingredients in the products, there's no requirement to show that these chemicals are actually safe before people are exposed to them.

Dr Andrea Gore

The chemicals that are used, for example, to make a water bottle don't need to undergo the same kind of safety scrutiny as a chemical that goes into a food product because making a water bottle, you're not intending for that chemical to get into the water. The problem is that it does get into the water through leaching.

NARRATION

As plastic degrades, like when left in the sun or put in dishwashers or microwaves, there's an accelerated leaching of plasticisers into the food or drink.

Professor Peter Sly

One of the most avoidable exposures that people as aware as they should be is heating food in microwaves in plastic containers. You can put them in pyrex or glass containers. They won't have the same problem. Heating baby's milk in plastic bottles in a microwave is completely unnecessary. If you are going to heat it, don't put it in the plastic bottle. Children's books with recycled paper are full of plasticisers. We think it's quite cute that kids chew on their books, but you don't realise that they're actually exposing themselves to these plastic products quite unintentionally. The heat-sensitive paper in the cash register receipts are full of plastic products - bisphenols and phthalates.

Dr Linda Birnbaum

We've just conducted a study where we've actually measured the levels of BPA in people who are cashiers. We measure before shift and then we measure after an eight-hour shift and, in fact, what we see is an increase in their levels over the time of the shift. So we know that the way a cashier handles receipts can lead to elevated exposure.

NARRATION

It's still not clear whether this level of exposure poses a health risk. Author and TV presenter Sarah Wilson has spent the last few years trying to minimise her exposure to chemicals.

Dr Maryanne Demasi

So what started you on this journey?

Sarah Wilson

Well, four or five years ago I found out that I had a pretty bad endocrinal issue, an autoimmune disease, and I knew that these endocrinal disruptors, you know, were playing a part or at least the science was pointing in that direction. I'd also come off the back of working in television quite solidly for a couple of years where I was being slapped on with, you know, make-up and hair products and so on. And I thought I should probably look into this.

NARRATION

It prompted Sarah to make some significant changes to her daily routine.

Sarah Wilson

I've cleaned out my cosmetic case. I keep to single ingredient items wherever I can. I simply use less of those kinds of products. I find that I don't need to use them as much. My cleaning products, I've changed a lot of those. I avoid canned foods, I avoid plastic containers. Shampoo is another area where I've made a difference as well. I use sodium laureth sulphate-free shampoos. I just figure wherever I can make a difference and it's not a big palaver, I might as well do it.

Dr Maryanne Demasi

Do you think it's made a difference?

Sarah Wilson

My skin has improved and my hair condition has changed as a result of not having all that silicon and guff on my face and in my hair.

NARRATION

Sarah and I have sent off some blood samples to compare our level of endocrine disruptors. Has Sarah's changes made a difference? We'll reveal the results later. Recently industry has responded to concerns. In Australia, for example, there's been a restriction of one phthalate in products used by infants up to three years of age. Also, many products now boast they're BPA free. But are these products actually safer?

Professor Peter Sly

What you're not told is that they have other bisphenols in them - other agents like bisphenol S, bisphenol AF, bisphenol B - and the health effects of these are starting to become known as well.

Dr Maryanne Demasi

On 1 January this year, France introduced legislation to suspend the use of BPA in packaged products that come into direct contact with food.

NARRATION

But industry groups are fighting back and calling for this ban to be overturned. Recently, the European Food Safety Authority has temporarily lowered the safe limit of BPA from 50 micrograms to 4 micrograms, pending studies. They estimate that this is still three to five times lower than the highest daily exposure.

Dr Andrea Gore

I think that level of four micrograms is rather an arbitrary number. There's really good evidence in the laboratory that levels of exposure much lower than four micrograms have effects on the developing brain, on the developing mammary gland and may relate to mammary cancer, on the prostate gland, on the thyroid gland. So I do not believe that if a chemical is an endocrine disruptor it can be considered safe at any level.

Dr Bruce Lanphear

You go back, the same statement was made about lead, the same statement was made about mercury, and PCBs and PBDEs. Time and again it's the same story. They don't know. I mean, you've seen this before, right? You look at study after study - we don't know, we don't know. Now this is harmful.

Dr Maryanne Demasi

So you disagree with the regulatory bodies?

Dr Bruce Lanphear

Yes. The regulatory system that's been set up assumes that these chemicals are safe until proven otherwise. So what the regulatory authorities are doing, what are governments are doing, are basically saying, 'We don't have enough evidence to show that these are guilty yet. So until we have definitive evidence from the laboratory, from a number of human studies, we're gonna continue to treat them as though they're innocent.' So in the end what we're doing, each time we release another chemical onto the market that hasn't been sufficiently tested is we're doing this massive experiment on our children, on all of us. I think what's happening is we're waiting for that crisis.

Dr Andrea Gore

Many of us are concerned that the people who are involved in the decision-making process are being influenced by groups that have a vested interest in those products. I consider it a conflict of interest if you make a product and you test that product yourself and say that it's safe to then use that as the basis for regulatory policy. I believe it's absolutely critical to bring in researchers who have no conflict of interest, who are not financially invested in a product and let them do the research in a controlled way and then make sure that that research is carefully peer reviewed.

NARRATION

Food Standards Australia New Zealand says that 'the weight of scientific evidence indicates that the levels of BPA exposure pose no public health and safety concerns for consumers.' They also said they 'assess both independent and industry sponsored studies and that they continue to review new information as it becomes available.' One difficulty faced by regulators and scientists is trying to assess the safety of multiple chemicals.

Dr Maryanne Demasi

When determining the toxic effects of a chemical, it's often done one chemical at a time. But this scenario is hardly a reality.

Professor Peter Sly

People are very seldom exposed to a single chemical at a time. We're exposed to chemical mixtures. And most people who study in the area, study one chemical at a time because it's technically easier. It's much more difficult to study mixtures and study the effects of mixtures. But the reality is people are exposed to mixtures of chemicals all the time.

Professor Ian Shaw

Now, my feeling is we should be regulating chemicals like BPA because I think their combined effect is really quite significant. But it's very difficult for regulators to take account of the levels of everything in the environment and consider BPA in the context of that cocktail. So each chemical is looked at individually and the individual levels are all far too low to have an effect. But the combined effect is what's important.

NARRATION

There are ways that individuals can try to minimise their exposure.

Dr Andrea Gore

If you wash your fruit and vegetables, you remove most of the residual pesticides. If you buy fresh foods instead of packaged foods, you're not exposing yourself to any contaminants that leach into your food or water. You also minimise creating a lot of trash, like the empty water bottles that are now getting into the oceans and the landfills. We can also keep our houses clean and thereby minimise having to spray with chemicals to try to get rid of the pests.

Dr Bruce Lanphear

You can choose to eat organic, if you can afford it. Try to eat fresh, unpackaged foods. Avoid canned foods. I tell my daughters this all the time, they don't listen - don't use cosmetics. There's a lot of things in cosmetics. Invariably every year there'll be another study about lead in lipstick. Phthalates are big in cosmetics. So I tried to tell my daughters, 'You're beautiful like you are.' And it doesn't work.

NARRATION

Since these are the kinds of changes Sarah has made, I'm curious to see whether her levels of endocrine disruptors are lower than mine.

Dr Maryanne Demasi

What did these blood samples tell us?

Professor Peter Sly

So, Maryanne, what we have on screen here is the results of your blood and Sarah's blood and average Australian women's blood.

NARRATION

It turns out that overall Sarah and I had similar results and our levels were slightly below the average Australian female.

Dr Maryanne Demasi

Overall our results seem to be fairly similar. Are you surprised given that Sarah goes out of her way to avoid these chemicals and I don't?

Professor Peter Sly

Unfortunately I'm not surprised. I think this is a reflection of the fact that these chemicals are everywhere and we don't know exactly what products they're in. If we don't know what they're in, it makes it much more difficult to avoid them.

NARRATION

Without clear labelling on products, consumers are exposed to many chemicals unknowingly.

Sarah Wilson

It's an absolute minefield out there. I don't think the average person could ever get round to understanding the labelling. It's the Wild West. Chemicals are absolutely everywhere. I'm trying to make a difference and it's not just because of my own personal health, it also just makes sense from an environmental point of view, and also financial point of view. The less guff you have in your life, the simpler your life is and hopefully the healthier it can be.

Dr Maryanne Demasi

And you feel better for it?

Sarah Wilson

I feel much better for it, yeah. I feel like my life is cleaner.

NARRATION

Now, there are populations, like the Amish, that shun modern technology and have significantly lower levels of BPA and phthalates. But this is unrealistic for most. A better way to control our exposure to environmental chemicals is through government regulation. In 2004, the Stockholm Convention ratified an international treaty to target chemicals with known impact on human health. The list, known as the Dirty Dozen, includes chemicals such as pesticides like DDT, and industrial chemicals like PCBs. For more than a decade, this lab in Queensland has measured the level of these chemicals in the Australian population. They found that the levels of DDT have decreased by more than a factor of ten since the 1970s. While some brominated flame retardants in children have decreased to less than half the concentrations ten years ago.

Professor Jochen Mueller

You can really see that the Stockholm Treaty works because it really led to the decrease of these chemicals in human serum in Australia.

Dr Maryanne Demasi

So it's a good news story.

Professor Jochen Mueller

That's a great story. I think that it shows that regulation works.

Dr Maryanne Demasi

So is it possible that these chemicals might be substituted with others of unknown safety?

Professor Jochen Mueller

There's definitely a chance. I think that's what happens that when you regulate one group of chemicals, the industry sees a need to replace it with some other chemicals. And so the way chemicals are regulated and considered to be safe are not bulletproof.

Dr Maryanne Demasi

It's almost like a human experiment.

Professor Jochen Mueller

Unfortunately, yes.

Dr Linda Birnbaum

Fearmongering never helps anybody, but denying the existence of concerns is equally harmful. I strongly believe that you have act when you have concerning information in the absence of certainty because science is rarely ever 100% certain.

Laureate Professor John Aitken

It would be something like the smoking debate where it wasn't until the horse has bolted that we suddenly realised that there was a link between smoking and lung cancer. The data was there suggesting this many decades before, but we were very slow to react to it. We don't want to be slow to react to this because reproductive toxicants are something that will impact upon us all. I don't think future generations will forgive us if we turn our back on this information and do nothing with it.

Professor Peter Sly

If you accept that the lag period between early life exposure and chronic disease in later life might be 50 years or so, then we're exposing generations of children and people to problems. Now, we know that these chemicals are already in people's bodies. There's enough evidence to suggest that they are harmful and that there's no benefit for them being there. So it makes perfect sense to me to act now rather than waiting for 50 years till we get definitive evidence.