Nice prawns, shame about the chemical cocktail

No longer a luxury item, king prawns have become a staple on our supermarket fish counters - but at what price?

Alex Renton reports from Vietnam where improverished producers have adopted some alarming intensive farming practices

Alex Renton, The Observer 21 Sep 08;

There's no lack of building materials around the prawn ponds of the Mekong Delta. Walls are constructed of the empty plastic sacks of pesticides and prawn feed. It's cheap, but sweaty.

Southern Vietnam is hot and sticky at any time and the humid air inside the Huong family's one-room hut, perched on a prawn-pond dyke, is rank with chemicals: we cough and sneeze when we enter. There's an acrid dust all over the mud floor, which makes you worry for little Huong Thi Mai, who is seven, a patient little girl sitting on the low bed near the door watching her parents work. I glance at her bare shins for signs of the skin infections that are common among prawn-farm workers, but she looks OK.

Mr Huong is proud: 'This is a very modern prawn-farming business,' he says. And, with luck and four months' hard labour, it is going to make him and his family quite rich. After they've paid their debts, the Huongs hope to buy a moped and their first fridge. Thi Mai might go to a new school. 'We can have a better life,' says Mrs Huong.

But until the tiger prawns are ready for harvest, and shipped off to Europe or America, the family must live here, keeping a 24-hour watch beside the sour-smelling pond. They've borrowed £4,000, a huge sum, to invest in prawn larvae, feed and medicines - and they need to keep alert in case anyone steals the growing crustaceans.

Modernity, for Mr Huong, appears to be chiefly measured in chemicals. I count 13 different pots, jars and sacks of these in the hut, and he eagerly talks me through them. He's particularly keen on a compound called 'Super Star' - the Vietnamese print on the label says it 'intensifies the metabolism to help prawns grow fat'. He learnt about this additive on a government-run course at the local fishery training centre. 'We're not allowed to use much - only 10 bottles per crop,' he says.

There are other glossy labels - most of them for products made in Thailand, the centre of the world's prawn farming industry. Mr Huong mixes up a feed in a big white basin while we talk. The basic feed, he says, is soya, broken rice and fish and prawn parts. But in it goes a large dose of 'Amino-Pro'. 'It will help the shrimp taste better,' he says. The label has familiar words from stock- cube packets: aspartic acid, glutamic acid and taurine, which is the key element of the energy drink Red Bull. Then there is Vitamix, 'to make prawns grow faster', Calphorax 'to help the shell thicken and give better colour' and Vin Superclear 'to kill pest, virus and smell'. And on top is a seasoning of antibiotic.

Prawn farming is an ancient activity in tropical countries. Coastal peoples in Indonesia and Vietnam have trapped young marine prawns in brackish ponds for at least 500 years, feeding them up with fish scraps and household waste to eat or sell. The prawns, properly farmed, are sweet and juicy: it's a lucrative business. The larvae can reach marketable size, as long as your hand, in as little as four months. But the trade has changed utterly since black tiger prawns (known as 'shrimp' in most countries) and bamboo prawns became a routine luxury in the rich world in the 1990s. The ancient cottage industry was swiftly industrialised. Around the tropical belt, from Ecuador to Indonesia, coastal farmers punched holes in the sea defences and let salt water into their paddy fields for the gold rush.

As with salmon, coffee and a host of other once rare and expensive foods, the demand from rich countries brought more and more producers into the market. Fifty tropical countries are now exporting large farmed prawn. Tiger or 'king' prawns and their siblings have become a staple of supermarket fish counters. The result - it's so familiar, it is almost a law of economics - has been ever-falling prices, increasing use of chemicals, dropping quality. And, of course, scares. Shipments of prawn from the tropics are regularly refused by governmental testers in Europe and America. The chemicals used in a production system that packs 20 of these wild animals into one square metre of foul, endlessly recycled water have been shown again and again to harm the workers, the environment and possibly the consumers. What's surprising, perhaps, is that we are still in love with them.

And we do eat a lot of them. 'King prawns to overtake burgers as barbecue food,' ran a news story last month. Tropical farmed prawns are now Britain's fifth most popular fish. Sales were up 14 per cent last year - and we now spend £169 million a year on them, four times as much as we spend on frozen burgers. At one supermarket which has seen a 20 per cent increase in sales, a spokesperson told me that tropical prawns are 'so fashionable' because they are 'a light and healthy option'. Enthusiastic endorsement from celebrity chefs has boosted the boom - recently Gordon Ramsay has salivated over king prawn and wonton soup on The F Word and Jamie Oliver told viewers to skewer them with bay leaves and lemon slices for the barbecue. Barbecued prawns with a saffron aioli appeared in The Observer's barbecue guide last month.

Light and healthy? I think about this as we follow Mr Huong through a litter of silicate sacks and empty prawn-feed bags to the pond. It measures 400 square metres, about two tennis courts. It was once the family's ancestral rice paddy, and at this time of year the growing seedlings should be turning the landscape a brilliant yellow-green. But the pond, and all the others nearby, is now a viscous grey, like old washing-up water.

Mr Huong paddles off in a little flat boat, scattering the feed we saw him mix up earlier. A system of paddle wheels, driven by a diesel engine, lies ready to stir up the water and bring oxygen to the shellfish packed beneath. There are 80,000 of them below the surface. Back on the dyke, he dips a flat net into the opaque water, and pulls up a few of the animals to weigh them and inspect them for deformities. They are two months old, about the size of my index finger. The translucent beige creatures wriggle and jump like busy grasshoppers.

The Huongs, like all their neighbours, opened the dykes and turned to prawn farming because of the fantastic profits available. A field that would have once provided enough rice for the family to eat, and a little extra to sell for essentials, has suddenly become an asset with the potential to change their lives. If this crop is successful the Huongs will sell the grown prawns for £8,000 - if prices hold up - after only four months.

This is an enormous amount in a country where many rural people still survive on less than £1 a day. As a result, many of the rice farmers of Tra Vinh have now become chemists, experts in the complex biology of intensively farmed crustaceans. Across the dykes we see men and women in their conical hats dipping test tubes in the water, testing acidity levels, examining prawns in the test nets for the dreaded signals of disease: reddening shells, misshapen bodies, white spots on their legs. They are trained and encouraged by the Vietnamese government, which, through promoting cash crops like this one, has been uniquely successful in Asia at increasing Vietnam's exports and reducing poverty in the country.

But there are calamities that can't be sorted out with science. If anything goes wrong the family will lose all their investment, and they won't have any rice to eat either. If they borrowed the money for the prawn larvae, they'll lose their land, too. Things happen here. This coastline along the South China Sea is prone to typhoons, which will destroy all the farmers' work in a night. The coastal mangrove forests, which once offered some protection to the people of these marginal lands, have been uprooted in many prawn farming areas across the tropics - the bandwagon of the shellfish gold rush has destroyed even these crucial natural barricades to the ocean.

The prawns, packed in the ponds, are terribly prone to illness. The last batch of prawn larvae all died after one month - the Huongs don't know why. White-spot virus almost killed off the industry in Vietnam two years ago. And, having gambled everything on prawns, people will of course do anything to protect their investment. That includes using any chemicals that may seem to help. 'Often we get consignments of antibiotics for human use, which are past the date they can be used by,' a village headman told me. It is well known that use of antibiotics can stimulate growth.

This is a temporary land, on loan from the ocean. It's tidy, almost Dutch, with its network of carefully constructed dykes and endless bridges, the South China Sea a pressing presence behind a row of raggedy firs. The mangrove forests have been replanted, after education work with the local communities, by Oxfam and the Vietnamese authorities. On the main road there's a sign, as big as an advertising billboard. Under a vivid picture of jars and bottles and dead prawns it lists all the chemicals that prawn farmers must not use: 51 of them. They include many human antibiotics, penicillins, and some names I recognise from the bad days of the European fish-farming industry - nitrofuran, chloramphenicol and organophosphate pesticides.

It's impressive and it shows the real efforts the Vietnamese government has been taking to educate farmers, reduce use of dangerous chemicals and improve quality. After all, export of farmed fish is worth $3.6 billion annually to the country. One government official said to me: 'We know Western people are suspicious of our seafood. There were scandals in 2002 that nearly destroyed our markets. So it is in our interest to keep quality high and reduce the use of chemicals.' And prawn farming has changed the face of Tra Vinh province. So much richer has the boom made this isolated corner of the Mekong's great delta that Oxfam will shortly end its long-standing poverty-reduction programmes.

'Shrimp has made this province rich,' the official said. And you can see it. Houses have televisions and mopeds outside them. School enrolment rates have soared. Five years after the scandals that nearly turned Europe off warm-water prawn, Vietnam's exports of the shellfish increased by 32 per cent last year. In Britain we're eating three times as many tropical prawns as we were five years ago - and the price of them has halved.

I ran the long list of chemicals we found past Peter Bridson, who is in charge of aquaculture at the Soil Association. He oversees the policing of the salmon farms in Scotland which, controversially, the Soil Association decided three years ago to certify as organic. Nothing we had found in Vietnam surprised him. 'This is what you see again and again in industrial aquaculture. There's a get- rich-quick attitude, everyone follows the boom. But then, one false step, and it crashes. And disease is usually the problem.'

Most of the chemicals we photographed in Mr Huong's shed are pesticides, feed enhancers and growth stimulants. 'These types of products are commonly used in Asian hatcheries,' says Bridson, who has worked in tropical fish farming. 'The farmers experiment. Someone chucks something in his tanks and gets good results. He tells his mates and the use of this product becomes mainstream in the area - whether it actually does anything or not.'

Mr Huong's Super Star contains a chemical commonly used as a 'nutritional enhancer'. It is marketed by the company Bayer in Europe as 'Butaphosphan'. On Bayer's website all I can find is a recommendation that it be used for injecting into sheep, dogs and cats suffering from 'stress, overexertion or exhaustion' and as a tonic in cases of weakness or anaemia in animals. (Bayer does not supply the chemical in Vietnam nor market it as a 'nutritional enhancer'.)

The problem is that some chemicals may do more harm than good - and not just to the image of the tropical prawn. Super Star also contains methyl hydroxybenzoate, an anti-fungal preservative that is banned in France and Australia and has been linked to cancer in some beauty treatments. The most dubious thing we found in the Huong's arsenal of chemicals was in a pot named 'N300'. It is a 'medicine for digestion and liver function', made by a Vietnamese company called Cong Ty TNHH. It had beta glucan, a harmless component of many human nutrition supplements, but also norfloxacin, an antibiotic usually used to treat gonorrhea and urinary-tract infections in humans. It is currently 'under watch' by the US Federal Drug Administration because of increased reports of nasty side effects, including damage to tendons.

Norfloxacin and its siblings, the fluoroquinolones, are banned for use in animals for human consumption in the States, and subject to EU controls in imports. Misuse of the fluoroquinolones is increasingly blamed for the rise in resistance to anti-bacterial medicines, and five floxacins are listed on the poster of banned chemicals we saw at the entrance to the village. Since 2005 Vietnam's fishery ministry has banned the use of fluoroquinolones in fish destined for the North American market, but not, apparently, for European countries. From the pile of empty N300 jars we saw, there is a lot of fluoroquinolone going into the feed for Mr Huong's prawns.

Numerous surveys have been done on the effects of the antibiotics that are used in prawn farming across the world (31 different ones were identified in Vietnam in a 2006 study, among a total 155 different drugs). They conclude that, although the antibiotics may rise to detectable levels in the bodies of the prawn, the most likely damage is being done to the environment in which they're farmed. It's Thi Mai who may have problems when doctors try to treat her for skin complaints, diarrhoea, respiratory problems and other bacterial infections, including malaria, which is common in this swampy landscape. They may find that she is resistant to the antibiotics. Scientists have speculated that some unusual outbreaks of salmonella poisoning in Europe and the States may have been started by antibiotic-resistant salmonella in farmed fish from Asia.

And the leakage of antibiotics and pesticides into the delicate ecosystem in the coastal shallows of the shrimp-farming countries will have effects that no one yet fully understands. Peter Bridson worries that the chemicals will intensify, because the water system is closed, with water being reused from one farm to another, and for human consumption. David Moriarty, a scientist at the University of Queensland who has studied the wide-scale use of norfloxacin and other anti-bacterials in aquaculture wrote nine years ago of disturbing effects in prawn farms in the Philippines: 'Many of the pathogens appear to have mutated to more virulent forms than were present a decade ago ... I feel that the incidence of disease has been exacerbated by the actions of the [prawn] farmers.' Moriarty now works promoting probiotics to tropical prawn farmers, as an alternative to lacing the waters with chemicals.

The Soil Association, meanwhile, which is currently processing applications to be certified organic from several tropical prawn farms, has decided not to allow any use of antibiotics in prawn-growing farms that want to carry its label. The Vietnamese, meanwhile, are working hard to police the use of antibiotics and other chemicals better. VASEP, the prawn exporters' and producers' organisation, points out that 25 new licences were granted to Vietnamese processors by the EU in January 2008, an endorsement of the fisheries ministry's 'urgent efforts' to improve sanitary and safety standards in the prawn industry.

So is that it for tiger prawn kebabs? How worried should we prawn lovers be? Well, norfloxacin is used by countless other farmers in Asia, but it is not illegal in most of those countries (though I could not find it on Vietnam's lengthy list of approved chemicals). There are increasing environmental fears about its overuse, and worries over the effect on human health of all the quinolones. But unless you have a serious king-prawn habit, you are unlikely to ingest anything like a human dose of norfloxacin.

Food & Water Watch, an American NGO that has studied prawn farming for 10 years, states in its latest report: 'The negative effects of eating industrially produced shrimp may include neurological damage from ingesting chemicals such as endosulfans, an allergic response to penicillin residues or infection by an antibiotic-resistant pathogen such as E coli.' That is a judicious 'may': a rational person in this age of food scares would have to conclude you're unlikely to suffer more ill effects from eating farmed prawns than from any other industrially produced food animal. But I wouldn't eat them every day.

It is certain, however, that banned or controlled chemicals are coming into the country with farmed prawns, despite the promises of governments and the retailers. Last year the EU rejected shipments of farmed prawn from six major exporters in India because they contained chloramphenicol and nitrofurans - two once-common antibiotics, one now known to cause leukaemia, the other a carcinogen.

The EU claims that this shows its regulations work, but the fact remains that the EU is thought to test only around one per cent of such shipments. America imports $3.9 billion worth of farmed prawn (or shrimp, as its known there) a year, yet tests hardly more of the shipments than does the EU. All the same, it rejected 2,817 shipments of seafood in 2005, most of them farmed 'shrimp'. And in Louisiana, a shrimp-producing region which conducts its own tests on imports, chloramphenicol was found in nine per cent of all foreign shrimp shipments in 2007.

I'm grateful to Taras Grescoe for that last piece of information. His fascinating new book, Bottomfeeder, describes the mad and scary practices of the fishing industry in nauseating detail. Grescoe says he thinks farmed prawn is the most disgusting of all the industrial farmed products - worse than salmon, worse than battery chicken. And he won't eat them.

It's not just the chemicals that turned him off. The land grab for prawn farms that has destroyed the mangrove forest has harmed wild animals and humans too. Seventy per cent of Ecuador's mangrove has gone. Rights to land are well-established in Vietnam, for women and men, but in other tropical countries there are disturbing reports of abuse of coastal peoples by big business cashing in on the boom. Food & Water Watch has visited one district of Andhra Pradesh in India where 2,000 families have become 'shrimp refugees', displaced by big corporations who wanted their land for prawn farms.

Unlike Grescoe, though, I'm not going to stop eating the prawns. That's too easy. Going on farmed-prawn strike won't hurt the villains in this story. They are, as in any tale of shipping the foods of the poor world to the rich in bulk, the big corporations, the processors and the retailers. They would survive a collapse of the industry - the people who won't are the poor coastal fishermen of Vietnam and 50 other countries, for whom prawn farming is proving a way out of poverty. These people have risked much to satisfy our demand for exotic seafood - there's no way back when you flood your family's rice paddy with seawater for tiger prawns. The salt from the water will make it impossible to grow rice again for years.

There are other ways to help them. Oxfam, which has been working in Tra Vinh for 10 years, is helping some of the farmers set up co-operatives and loan schemes to make traditional fishing and farming more lucrative: we visited villages where the whole community has become partners in a cockle-fishing enterprise. Its sustainable, it creates jobs and it's doing well.

But to make a difference across the tropics, we customers must demand better prawns, raised organically and in a way that's good for them and the people who farm them. We have to be prepared to pay more for them. On my desk I have a 212g box from my local supermarket of uncooked peeled king prawns from Vietnam, which I found on sale at a two-for-£5 deal. That means the 60 or so prawns cost me about 12p each - after shelling, freezing, packing and shipping. That is just two pence more than Mr Huong hoped to sell his prawns for. It's not enough. The price is the same for trawled wild prawns from the North Atlantic.

Bad prawn farming is caused by the same things as bad chicken farming - the relentless downward pressure on prices forced on producers by supermarkets. So, there's a good reason to buy organic. And a good reason too, to ask your supermarket to ensure that more of the money you are spending on a tiger prawn goes back to Mr Huong and his colleagues. Pay him a bit better, and he could farm a bit better. It's that simple.

Prawn cocktail: the chemicals used in one Vietnamese prawn pond

Butaphosphan is a veterinary medicine to treat metabolic and developmental disorders.

Methyl Hydroxybenzoate is an anti-fungal agent, also known as methylparaben. In beauty products parabens have been called hormone disrupters and reported to cause contact dermatitis. The science is as yet unclear and disputed by the cosmetics industry. A recent literature review of studies on methyl paraben found it to be 'practically non-toxic' with no evidence that it accumulates in tissue.

Norfloxacin is an antibiotic used to treat certain bacterial infections such as gonorrhea, prostate, and urinary tract infection. Norfloxacin and other fluoroquinolones are banned for use in animals for human consumption in the States, and subject to EU controls in imports. Over-use of antibiotics leads to resistance to them.