Tin can lining may harm male embryos

A mass-produced chemical which lines the inside of tin cans can harm male babies as they develop in the womb, an embryologist told a conference yesterday.

The chemical, called bisphenol A, is one of 60 known "gender-bender" substances - chemicals which can mimic naturally-occurring hormones and which a growing number of scientists believe are affecting wildlife and humans, causing illness and putting fertility at risk.

Professor Frederick vom Saal, of the University of Missouri, said his studies on mice and on human cells kept alive in test tubes had convinced him the intake of bisphenol A that people received in a normal western diet could harm developing male embryos.

He found that when very low concentrations were given to pregnant mice, their male young had a permanently enlarged prostate gland and a 20 per cent drop in sperm counts when they matured. His laboratory and three others had also demonstrated that the chemical caused a hormonal response in cultured human breast tissue cells.

In the foetus, the great majority of naturally-occurring oestrogen molecules circulating in the blood are attached to proteins and as such are unable to enter cells. But, said Professor vom Saal, "We found that bisphenol can bypass this barrier system."

He pointed out that the prostate gland sighted just beyond the bladder, was "the most diseased organ in the human body" with most elderly men experiencing some problems. Anything affecting the embryo which enlarged the developing prostate more then normal should be avoided, he said.

"We now have an animal study which shows that at the level found in our food, bisphenol A will have an impact on the male foetus ... it has to be perceived as a potential risk, especially to pregnant and breast feeding women and their babies," he said.

As well as being used in can linings, the chemical is a building block in a common plastic, polycarbonate, found in compact discs. It is also used as a sealant in dentistry. Professor vom Saal attacked some chemicals and manufacturing companies for refusing to tell health researchers what chemicals they use in their plastics. "Tupperware told me we do not release this information to the public."

He was one of several scientists talking to a conference organised by the Global Legislators' Organisation for a Balanced Environment and the Worldwide Fund For Nature. It was attended by MEPs and parliamentarians from several continents but no British MPs.

Many environmentalists see synthetic chemicals which interfere with hormone systems during the embryonic development of humans and animal species as a major green issue which will come to rival global warming in importance.

They believe the substances are to blame for rising rates of testicular cancer, falling sperm counts and an increase of cases of malformed, under-sized penises and undescended testicles.

Start your day with The Independent, sign up for daily news emails
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Ashdown Group: Front-End UI Application Developer

£30000 - £40000 per annum + Benefits: Ashdown Group: Front-End UI Application ...

Recruitment Genius: Digital Account Executive

£18000 - £26000 per annum: Recruitment Genius: They work with major vehicle ma...

Recruitment Genius: Service Engineers - Doncaster / Hull

£27000 per annum: Recruitment Genius: Domestic Service Only Engineers are requ...

Recruitment Genius: Employability / Recruitment Adviser

£23600 - £27500 per annum: Recruitment Genius: The Employability Service withi...

Day In a Page

Where the spooks get their coffee fix: The busiest Starbucks in the US is also the most secretive

The secret CIA Starbucks

The coffee shop is deep inside the agency's forested Virginia compound
Revealed: How the Establishment closed ranks over fallout from Loch Ness Monster 'sighting'

How the Establishment closed ranks over fallout from Nessie 'sighting'

The Natural History Museum's chief scientist was dismissed for declaring he had found the monster
One million Britons using food banks, according to Trussell Trust

One million Britons using food banks

Huge surge in number of families dependent on emergency food aid
Excavation at Italian cafe to fix rising damp unearths 2,500 years of history in 3,000 amazing objects

2,500 years of history in 3,000 amazing objects

Excavation at Italian cafe to fix rising damp unearths trove
The Hubble Space Telescope's amazing journey, 25 years on

The Hubble Space Telescope's amazing journey 25 years on

The space telescope was seen as a costly flop on its first release
Did Conservative peer Lord Ashcroft quit the House of Lords to become a non-dom?

Did Lord Ashcroft quit the House of Lords to become a non-dom?

A document seen by The Independent shows that a week after he resigned from the Lords he sold 350,000 shares in an American company - netting him $11.2m
Apple's ethnic emojis are being used to make racist comments on social media

Ethnic emojis used in racist comments

They were intended to promote harmony, but have achieved the opposite
Sir Kenneth Branagh interview: 'My bones are in the theatre'

Sir Kenneth Branagh: 'My bones are in the theatre'

The actor-turned-director’s new company will stage five plays from October – including works by Shakespeare and John Osborne
The sloth is now the face (and furry body) of three big advertising campaigns

The sloth is the face of three ad campaigns

Priya Elan discovers why slow and sleepy wins the race for brands in need of a new image
How to run a restaurant: As two newbies discovered, there's more to it than good food

How to run a restaurant

As two newbies discovered, there's more to it than good food
Record Store Day: Remembering an era when buying and selling discs were labours of love

Record Store Day: The vinyl countdown

For Lois Pryce, working in a record shop was a dream job - until the bean counters ruined it
Usher, Mary J Blige and Will.i.am to give free concert as part of the Global Poverty Project

Mary J Blige and Will.i.am to give free concert

The concert in Washington is part of the Global Citizen project, which aims to encourage young people to donate to charity
10 best tote bags

Accessorise with a stylish shopper this spring: 10 best tote bags

We find carriers with room for all your essentials (and a bit more)
Paul Scholes column: I hear Manchester City are closing on Pep Guardiola for next summer – but I'd also love to see Jürgen Klopp managing in England

Paul Scholes column

I hear Manchester City are closing on Pep Guardiola for next summer – but I'd also love to see Jürgen Klopp managing in England
Jessica Ennis-Hill: 'I just want to give it my best shot'

Jessica Ennis-Hill: 'I just want to give it my best shot'

The heptathlete has gone from the toast of the nation to being a sleep-deprived mum - but she’s ready to compete again. She just doesn't know how well she'll do...