Re Meat Free Monday SOME people who give up eating meat and poultry continue to eat fish in the belief that it is a healthy food and that fishing is less cruel and environmentally destructive than farming. Nothing could be further from the truth.

Numerous studies, including a recent study by the Roslin Institute and the University of Edinburgh, have found conclusive evidence that fish do feel pain. Dragged from the ocean depths, fish undergo excruciating decompression. The intense internal pressure ruptures their swimbladder, pops out their eyes, and pushes their stomach through their mouth. They are then tossed onboard where many slowly suffocate or are crushed to death. Others are still alive when their throats and bellies are cut open.

Commercial fishing of the oceans has decimated both fish stocks and the aquatic environment. Some fish species are close to extinction as a result.

Of the 100 million tons of fish caught from the seas of the world each year, between 60 and 80 million tons are caught by trawling. Non-target species are discarded. This can include almost every creature from the sea or sea bed - sea urchins, brittle stars, seals and sea-birds. In addition, thousands of endangered sea turtles are killed in shrimp nets every year and drift nets kill thousands of dolphins, porpoises, small whales, sea lions and walruses.

Over fishing and the subsequent collapse of many commercial fisheries has led to an increase in fish farming. There are 340 salmon farms in Scotland. It takes five tons of fish caught from the sea to produce one ton of factory farmed salmon. Inland factory-farmed fish are kept in shallow concrete troughs. The intensive crowding - as many as five fish per square foot - spreads infection and parasites, so factory fish farmers use antibiotics, growth promoting drugs and disinfectants to get more fish fatter faster.

The pollution from fish farms is horrific. It has been estimated that the amount of pollution in Scotland due to ammonia output from fish farming is comparable to sewage produced by 9.4 million people.

Fish is often claimed to be a healthy food but the flesh of fish often stores dangerous contaminants, such as PCBs, dioxins, heavy metals and even radioactive materials. PCBs and dioxins are suspected of causing cancer, nervous system disorders and foetal damage. Toxic metals in fish like cadmium, mercury, lead and arsenic can cause health problems ranging from kidney damage and mental retardation to cancer. They can be especially dangerous to unborn children. Fortunately, the healthful substances found in fish can be obtained from plant sources which contain no risk of contamination.

Becoming vegetarian, or at the very least greatly reducing your consumption of all animal products, is one of the most important and effective actions you can take to ease the strain on our Earth's limited resources, stop cruelty, protect the environment, and improve your own health.

MRS M HARRISON Beaulieu Close Toothill Swindon