Could cling film really make us sterile, or cause cancer? For decades, holistic health gurus have warned of the toxic impact of plastic. They have been dismissed as quacks – but now it seems their paranoia might have been justified.

New evidence suggests that heat makes chemicals in plastic storage boxes and bottles leach into food and drink: two major reports last year linked 175 compounds to health problems connected to cancers, fertility and foetal development.

Even Cancer Research UK, which has so far been sceptical, is now warning that cling film should not be allowed to touch the food it is covering during microwaving.

Doctors are now warning that cling film should not be allowed to touch the food it is covering during microwaving

The chemical causing most concern is Bisphenol A (BPA), which is widely used in plastics manufacture. In the body, it mimics the effects of female sex hormone oestrogen.

Laboratory studies have also linked BPA with breast and prostate cancer and early sexual development in women.

THE SAFE OPTIONS - INCLUDING FOR A BABY Chilly’s Chilly Bottle Blue 500ml 1 Chilly’s Chilly Bottle Blue 500ml An ultra-light alternative to that plastic gym bottle, this reusable lightweight flask keeps drinks cold for 24 hours or hot for 18, and is BPA-free. £16.99, gooutdoors.co.uk 2 Lifefactory 2-Cup 475ml Container Not as light as Tupperware – but better than reusing an old ice-cream tub for your packed lunch. The silicone outer ‘shell’ protects this BPA-free glass storage box from breaking and doubles up as a lid. £16.99, planetorganic.com Lifefactory 2-Cup 475ml Container 3 If You Care Paper Sandwich and Snack Bags These greaseproof bags are made from the unbleached pulp of Scandinavian spruce trees, are not chemically treated and keep bread soft for up to six hours. £3.90 for pack of 48, goodnessdirect.co.uk If You Care Paper Sandwich and Snack Bags 4 Avent Natural Glass Bottle 120ml Replace plastic baby bottles – which are heated on a regular basis – with this stylish glass version, which comes with a BPA-free silicone teat. £7.50, greenweez.co.uk Avent Natural Glass Bottle 120ml 5 Stainless Steel Ice Cubes There’s no need to worry about ageing ice-cube trays, but you can put these in the freezer instead. They are reusable and chill drinks but do not melt, which means no risk of BPA contamination (or diluting the taste of your tipple!). £9.48 for six, lightinthebox.com Stainless Steel Ice Cubes Advertisement

Andrea Gore, professor of pharmacology at the University of Austin in the US, who has studied the effects of chemicals on reproductive function, says: ‘I heat food only in glass or ceramic, and although I use cling film in my fridge to cover cooked food, I remove it before reheating that food in the microwave.’

So when is plastic OK to use – and when do the experts think we should avoid it? Here’s their advice…

DON’T REUSE PLASTIC WATER BOTTLES

You may feel it’s thrifty to refill old plastic mineral water bottles from the tap.

But research shows that this should be avoided, says Prof Gore. ‘They used to be made using BPA, or bisphenol-A, which is a known endocrine disruptor.

When brand new, this is least likely to cause problems, but as the plastic decays, particles of the BPA can be released into drink or food that touches it.”

Most manufacturers have now switched to bottles made of PET (Polythethylene Terephthalate) which does not contain BPA and which, they say, is safe and complies with European and UK requirements.

‘Many baby bottles now make a selling point of being BPA-free, but we don’t know what chemicals are replacing BPA and the manufacturers don’t have to tell us,’ says Prof Gore.

Consumer tests have found BPA is still found in many plastic bottles and other plastic food utensils sold in the UK.

Breast Cancer UK is calling for a British ban, bringing us in line with other European countries and concerns are starting to emerge that even PET plastics may contain a possibly harmful chemical called antimony trioxide.

Many scientists say bottles known to be free of BPA are safe to drink from and then throw away.

‘If you drink bottled water and then refill the bottle, it’s best to use for a short period rather than weeks, and then discard,’ says Ashley Grossman, professor of endocrinology at the Oxford Centre for Diabetes, Endocrinology and Metabolism. Switching to glass or lightweight metal sports bottles is an alternative.

DITCH THE LUNCH BOX

Many reusable plastic food containers – including Tupperware – are also made with BPA. Old containers that are showing signs of wear are particularly suspect.

Dr Thomas Zoeller, professor of biology at University of Massachusetts, advises: ‘Replace all those which have been used and washed harshly, as these are most likely to be unstable and prone to releasing BPA into the food.’

KEEP PLASTIC OUT OF THE DISHWASHER

Whether it’s cutlery, storage containers or bottles, heating, even in a dishwasher, causes the compounds to become less stable making particles more likely to leech into food, says Prof Gore.

A study published in the journal Environmental Health Perspectives showed that 95 per cent of plastic products put through a dishwasher proved positive for leaching chemicals that had an oestrogen-like effect on the body.

BEWARE THE CLING FILM

‘Do not allow cling wrap to come into direct contact with food when heating it,’ advises Cancer Research UK.

Experts at Johns Hopkins University in the US concur, warning that heating food covered with plastic can melt the plastic on to the food.

Of particular concern is cling film made from PVC, which contains hormone-disrupting phthalates, a chemical that keeps plastic soft. PVC cling film has been banned in America, but it is still in use in Europe.

‘If you’re heating a plate in the microwave, just cover it with another plate or a chemical-free paper towel,’ adds Prof Gore.

CHOOSE NATURAL

Styrene, a component of polystrene cups and some egg cartons, has been classified as a possible carcinogen by the US’s International Agency for Research on Cancer, and benzene, also used in production, is another suspected carcinogen. Avoid, say the experts.

Many takeaway chains now offer wooden disposable cutlery, and if your children use straws, switch from plastic to paper ones.

GO FOR POP IN CANS

Fizzy drinks may be packaged in bottles that contain formaldehyde, a known toxicant, so some experts recommend choosing cans.

Concerns over its legal use in packaging were raised in last year’s report in the Journal Of Epidemiology And Community Health, as it is potentially a carcinogen.

However, some scientists point out that formaldehyde is also found in some foods, including apples.

DON’T WORRY ABOUT THOSE ANCIENT ICE-CUBE TRAYS

Reusable ice-cube trays can get heavy use in a kitchen – and over the years will show signs of decay.

It is a myth, though, that freezing water in plastic ice-cube trays releases dioxins, another dangerous chemical.

The scare arose out of an internet hoax – and scientific studies have shown that the freezing process actually prevents chemicals leaching out of plastic.