Hello and welcome to more or less on the BBC World Service.

We're looking at a really complicated issue this week.

It's about glyphosate.

A herbicide said to be the world's most widely used weed killer.

It's used on farms, but also in places like parks and schools and by people in their gardens.

And it's been linked to cancer.

Popular weed killers are alleged linked to cancer, stirs widespread concern.

The weed killer raises risk of non-Hodgkin lymphoma by 41%.

Glyphosate was thought to be safe because it works by blocking an enzyme in plant growth,

which doesn't exist in humans.

So in many countries around the world, farmers use glyphosate to kill the weeds they want.

American cancer epidemiologist Dr. Jeffrey Kabat.

It's been in use since the 1970s and it's a ecologically fairly benign compound and is important

because it allows us to suppress weeds and to increase agricultural yield.

And it has the acute toxicity, which is less than or comparable to table salt.

Finding what causes cancer is complicated, not everything is as simple as smoking causes

lung cancer.

But over the last few years, there have been studies that suggest exposure to glyphosate

increases the risk of developing non-Hodgkin lymphoma, or NHL, a type of cancer that develops

in your lymphatic system.

A network of vessels and glands spread throughout your body.

There are lots of people and organisations on different sides arguing for or against this.

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