Crystalline sponges pocked with pores that are just the right size to trap carbon dioxide molecules could filter the fumes from power stations and cars. What's more, the trapped CO2 can then be sucked from the crystals and piped into containers and buried underground, allowing the crystals to be reused.

To lose weight, bin the diet cola. That's the message from studies showing rats got fatter on diets containing artificial sweeteners than on those with sugar.

Using biofuels instead of fossil fuels will do little to cut carbon emissions, and could even increase them because of the extra land the crops will require.

Judging the effect of climate change on ocean currents could take longer than we thought. The circulation of warm water in the North Atlantic is suspected to be slowing, and the worry is that global warming is to blame.

Campaigners against airport expansion have some new evidence to support their case. A study of 140 people living near four European airports concludes that loud night-time noise raises blood pressure, even when people are asleep.

When it comes to Antarctica's disintegrating ice shelves, climate change often gets fingered as the cause. But it turns out global warming was not the only culprit behind the continent's biggest ice break-up in recent years.

The wildlife trade monitoring network TRAFFIC issued a wake-up call to the Indonesian authorities this week: stop the illegal trade in Sumatran tiger body parts or the species will be hunted to extinction.

THE US Environmental Protection Agency is in trouble again. Already under fire for failing to get tough on carbon dioxide emissions, the agency has now had its scheme for dealing with mercury pollution ruled illegal.

It is well known that when the dangers of smoking became increasingly obvious in the 1950s, tobacco companies funded scientific research aimed at downplaying the risks. Now, a little-known strand of that campaign, aimed at giving an intellectual gloss to pro-smoking arguments, has been detailed for the first time.

Antarctica is the most unspoiled continent on Earth - and fast becoming a tourist hotspot. It has been 50 years since the first cruise ship visited with 200 passengers, but now 30,000 tourists go each year. Veteran polar researcher and zoologist Bernard Stonehouse has seen for himself how Antarctica has changed: he first set foot there in 1946 and since the early 1990s has been back every year to study the impact of tourism. He tells Henry Nicholls why tourists are important to Antarctica, and why scientists may pose a greater threat to its environment. (Interview)