THE GREAT QAT RACE

The leaves of Catha edulis induce a state of euphoria - as long as they are chewed within 24 hours of being picked. For thousands of Yemeni users in the UK, this presents a problem. On these pages, in words and pictures, we follow the drug's hectic journey from Yemen to London

It is mid-morning in the main souk in Sana'a and a crowd is gathering. The day's consignment of qat has arrived. Men from all walks of life swarm to buy their daily supply of the leaves that offer solace, euphoria - and, ultimately, oblivion. They will take their small bundles to large public rooms, or to their homes, where they will sit around with friends and chew. The same scene is being played out in cities, towns and villages up and down the Yemen. In a country where alcohol is banned by Koranic law, the leaves of the plant Catha edulis offer social lubrication and escape. Chewing the plant releases cathinone, a chemical which stimulates the heart rate and blood pressure, and suppresses the appetite. Its effect is similar to that of a mild amphetamine.

The problem for the distributors of qat is that, after the leaves are harvested, the cathinone remains active for only 24 hours - and some qat- users are based thousands of miles away. The pictures on these pages show the qat trail, from the fields, via central distribution points, to the souks of Sana'a - and beyond. Twice a week, freshly-harvested plants are flown from Sana'a into Heathrow and Gatwick to supply Yemeni communities in London, Birmingham and Sheffield. Qat is also sold to expatriates from Ethiopia and Somalia.

Although qat is not thought to be highly addictive and is legal both here and in its countries of origin, the WHO and the UN have campaigned against it for years, and the Yemeni government uses taxes and subsidies to discourage its growth and use. The danger comes from a psychological dependence which can impoverish users and their families. Yemenis are estimated to spend a third of their incomes on the leaves. The smallest bag costs around 60p; a night's consumption can run to pounds 12. Growers, meanwhile, are among Yemen's highest earners: the average qat producer makes between 5m and 6m Yemen Rial a year (pounds 33,000); the average worker makes 80,000 Y/R (about pounds 440).

While I was taking these photographs, bundles of qat kept being pressed into my hands, and I tried it several times, more out of respect for the people I was photographing than for any other reason. My first experiences were unpleasant: the leaves tasted bitter and instead of storing the masticated qat in my cheek I kept swallowing it. I persisted because I was eager to be invited to a "public" chew. It wasn't until my third chew that I felt any effects.

The seller advised me to suck on a mint or a clove to counteract the taste and gave me tips on how to store the leaves in my mouth. With my pounds 1.20 bag of qat I made my way to a large warehouse crowded with men sitting around cafe tables. They were staring vacantly at several small TV screens, each man with one cheek distended, some to the size of a tennis ball. I found a seat and started chewing. After sitting through a couple of Hindi films, with dancing girls in wet saris, and the B-est B-grade karate movie, Karate Cop, I got up to leave halfway through an Egyptian romance. I felt incredibly light on my feet and a bit buzzy, as if I had drunk a dozen espressos. As I walked back to my hotel everything seemed really vibrant. I was desperate for a pee - qat makes you very thirsty and I had drunk a fair bit of water. But I found it very difficult to relieve myself, and the discomfort of a full bladder stayed with me for some time. This is one of the more innocuous side-effects of qat-chewing.

In Britain, drug-workers are particularly worried about the abuse of qat among Somali refugees in east London, where unemployment is high and life offers few pleasures. Again, the biggest perceived danger is economic - in London, it costs around pounds 5 a hit - but there are also health implications. People chewing a lot of qat have little appetite for food, and malnutrition is not uncommon among regular users, particularly if they are poor. And there is also potential psychological damage: doctors believe that qat's similarities to amphetamines include the possibility of inducing temporary psychosis.

The Wadi Dhahr region (above), 30 miles east of Sana'a, where some of the best qat in Yemen is grown. Farmers have little incentive to grow anything else as the crop can earn them 75 times the average income

7.30 AM: pickers on a plantation near Sana'a - many of them chewing the leaves as they work. The production and sale of qat is legal in Yemen, but the government is increasingly concerned by problems of over-use

8.30 AM: farmers washing and packing the freshly picked qat before dealers arrive to collect the harvest for market. The leaves have to be chewed within 24 hours for the active ingredient, cathinone, to work

8.45 AM (above): workers rush with bundles of qat leaves to the dealer waiting in the Landcruiser, who then drives to meet the wholesalers

9.30 AM (right): wholesalers wait for clients at a roadside north-east of Sana'a. Shop and market-stall owners buy here, and some small-time sellers also pick up supplies to sell from the boots of their cars

10 AM: qat-sellers buy their day's supply from the wholesaler's truck on the outskirts of the town of Dholla

10.15 AM: then it is on to the public markets of Sana'a and the other main towns. Speed is of the essence

11.30 AM (centre, top): qat-sellers using their pick-ups as shops in Dholla market where crowds begin to gather (centre, below), bargaining for their daily supply of leaves; (above) a young qat-seller at Sana'a's main city market. Enough qat for a day's chewing can cost anything up to pounds 12, and Yemenis are estimated to spend as much as a third of their annual incomes on qat. But some of the buyers are buying for export

4 PM: the day's UK consignment has flown. Dealers and buyers settle down for an afternoon's chewing

7 PM: the British connection - a Yemeni inspects shoots just arrived at Gatwick airport from Sana'a. There's a twice-weekly delivery. A dealer (right) loads leaves for transport to qat-chewing communities in Britain

11.30 PM: two Yemeni men returning to their London communities by Underground with a fresh supply