When Edzard Ernst became the UK's first professor of complementary medicine, he was attacked by both alternative therapists and conventional doctors. The doctors have come round, but he is now alternative medicine's public enemy number one after sticking the needle into everything from acupuncture to homeopathy. He insists he is just being a good scientist, but it has been a long journey for someone whose family doctor was a homeopath.

Among the many environmental concerns surrounding nuclear power plants, there is one that provokes public anxiety like no other: the fear that children living near nuclear facilities face an increased risk of cancer. Though a link has long been suspected, it has never been proven. Now that seems likely to change.

Tens of thousands of American families may be living in buildings once used as methamphetamine labs - most of them oblivious to the fact. Some who have learned of their home's history similarly attribute mysterious ailments to the toxic legacy of illicit drug manufacture, but like Katrina Evans they are finding that there is precious little firm knowledge about what risks they are running. Only now is a new federal law authorising more research into the problem, and promising to fill in some gaps.

Livestock auctions are not normally the stuff of headlines, but then it's not every day that cows as unusual as Dundee Paradise and Dundee Paratrooper are going under the hammer. The dairy cows were due to be sold at Easter Compton cattle market near Bristol, UK, last month, but at the last minute their owner withdrew them, reportedly unsettled by negative media coverage and local opposition. The problem? The cows' mother was a clone, conceived in a laboratory from a cell taken from the ear of a prize-winning Holstein in Wisconsin.

If war ever breaks out in space it's not the loss of individual satellites that will do the damage, but the debris this produces. It will stay in orbit and go on harming satellites for decades, according to two studies presented at the American Physical Society meeting in St Louis, Missouri, last week.

To protect the health of humans, save other species. That's the message from Eric Chivian and Aaron Bernstein from Harvard Medical School in Boston, who say that human health depends crucially on biodiversity.

There may be more to global warming than we thought. On top of the effect of human-made carbon emissions, natural changes in the warm ocean currents travelling to the icy north may be helping to heat up the entire northern hemisphere.

Rich nations, including the US and UK, are planning to push rapidly industrialising nations like China and India into accepting "back door" limits on their greenhouse gas emissions. They want climate negotiators to agree global technical standards on "dirty" manufacturing industries like aluminium, iron and steel, cement and chemicals - standards that would apply equally to factories in the US, Italy or India, for example. This strategy emerged last week in meetings at the Royal Society in London to discuss the successor to the Kyoto protocol, which expires in 2012.

CLIMATE change is "the greatest market failure the world has ever seen". That is the view of no less an authority than Nicholas Stern, former chief economist at the World Bank, and he has a point. As long as the market exacts no penalties from companies or industries that emit the gases that are beginning to transform the planet's climate, it can do nothing to keep pollution in check as economies grow. So is there some way to fix the market so that it punishes polluters and encourages greener growth? (Editorial)

There's little doubt that free-market capitalism helped to get us into the mess we're in. As Nicholas Stern, former chief economist at the World Bank, puts it: climate change is "the greatest market failure the world has ever seen". The question now is whether capitalism is able to make amends. Can it provide a mechanism that rewards people for reducing their carbon emissions instead of increasing them? Or will it simply give big polluters a way of dodging their responsibilities?