The Co-op supermarket chain has banned the use of certain potentially dangerous chemicals from everyday household products.
The Co-op has replaced perfume chemicals in its fabric conditioners
The company believes the man-made chemicals - all legally used - can be linked to cancer, fertility problems and environmental damage.
BBC News Online looks at the science behind the move and what it could mean for consumers.
Q: What types of chemicals have been banned from Co-op own-brand products?
The Co-op has concentrated on substances suspected of having links to cancer, hormone disruption, fertility problems and environmental damage.
They include chemicals found in cleaning products and artificial musks, used in perfumed products, which can be absorbed by the body.
These "bio-accumulators" tend to build up in fatty tissues over a period of time because they are difficult to break down.
Environmental campaigners say the long-term effects of accumulating a cocktail of potentially hazardous substances in the body are not known - so safer alternatives should be used instead.
Q: Where might these chemicals be found?
Everyday household products like household cleaners, fabric conditioners and furniture polish have been targeted by the Co-op.
The company has banned the use of phthalates - a type of chemical found in all kinds of flexible plastics - from its own-brand lavender furniture polish.
Dr Giles Watson, toxics policy officer for the World Wildlife Fund-UK (WWF), said the chemical had been linked to hormone disruption and reproductive abnormalities.
But they are still found in everything from hospital blood bags to nail varnish.
The Co-op has also replaced polycyclic musks and nitro musks in its fabric conditioners, household cleaners and air fresheners because they are bio-accumulators.
Q: On what has the Co-op based its list of banned chemicals?
The Co-op has appointed an independent advisory panel to look at ways to replace chemicals under scrutiny from the international scientific community with more benign alternatives.
Dr Charles Clutterbuck, a panel member and part of the UK Government's Advisory Committee on Pesticides, said their decisions were based on the "precautionary principle".
"Where there may be risks we don't necessarily wait for the evidence to build up before doing something about it," he said.
"What we are saying is we believe these are priority chemicals for action. We produced the lists from chemicals the EU or UN determined a priority but haven't got sufficient evidence to ban."
Q: What effects might these substances have on health?
There are a number of health concerns.
Chemicals known as endocrine disruptors - like phthalates - tend to interrupt hormones and so may disrupt gender and sexuality.
This can lead to feminisation - males becoming like females - and reproductive problems like decreased sperm production or undescended testicles.
Other substances, like the artificial musks, can build up in fatty tissues and fluids like breast milk and blood - but it is not yet known if they are harmful.
Justin Woolford, director of the WWF Chemicals and Health campaign, said they were concerned about the combinations of chemicals accumulating in humans.
He said: "There are associations with things like increasing rates of breast cancer or infertility or declining sperm counts or the potential impact on children's intelligence or behaviour.
"The potential outcomes manifest themselves much, much later on - a child might be affected in the womb but won't see the effect until a teenager."
Q: How seriously should I take these health concerns?
Experts disagree over how harmful certain substances may be - and in many cases, little or no data is available on which to base their judgement.
Dr Paul Harrison, director of the Medical Research Council Institute for Environment and Health, said people must "accept that these are judgements and not the truth".
He said: "The chemical industry does take health and safety very seriously.
"It does their business no good at all if they are selling anything dangerous - it's not an 'us against them' situation but sometimes there are things that can be done.
"These situations can provoke people into taking action which is right and proper - but it shouldn't turn into a witch hunt or accusations of poisoning the environment."
Mr Woolford said: "The lack of data about chemicals in current use is such that we are part of a big global experiment to see what happens."
Q: What can I do to avoid exposure to these chemicals?
Tips from the WWF-UK and Co-op include:
- Buy organic produce wherever possible
- Wash and peel fruit and vegetables before eating
Avoid canned food - use fresh, frozen or dried foods instead
Avoid food coming into contact with PVC cling film
use non-polycarbonate baby feeding bottles or, better still, breast feed babies
Buy soap, shampoos and cosmetics without synthetic fragrances
Use paints, varnishes and glues with a low VOC (volatile organic compound) content - often marked on labels
Avoid the use of pesticides in the home or garden
Open your windows instead of using air fresheners
Q: Will consumers notice the difference?
Products like washing powders may no longer have that "just washed" smell if an alternative to possibly harmful perfumes has not yet been found.
Dr Clutterbuck said: "Customers may say that loss of a bit of smell to save the north Atlantic from pollutants is worthwhile."
Q: Is the government doing anything to restrict the use of potentially harmful chemicals?
Proposals drawn up by the European Commission on the regulation of chemicals are due to come before the European Parliament later this year.
Campaigners are trying to put pressure on the chemical industry to use safer alternatives where available.
Q: Have other chemicals been banned in the past for their effect on human and animal health?
Several chemicals have already been banned from use either in Europe or globally because of their harmful effects on the environment or health.
Some organochlorine pesticides, like DDT, can still be found in human tissue but were banned from use (except in certain malarial areas) in the 1970s because of bio-accumulation.
Other chemicals no longer permitted in Europe because of concerns over bio-accumulation include flame retardant substances used in sofas, televisions and carpeting.