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Gender-bending pollutants cause alarm
Scientists working along the south-west coast of Britain have discovered widespread evidence of chemicals disrupting the sexual development of sensitive marine organisms.
In a study published last week, the researchers report the first cases in which hormone-disrupting pollutants are believed to be responsible for a gender-bending effect on marine invertebrates living in British estuaries. The finding has caused alarm because the affected species are crucial for the health of the ecosystem, in some cases forming the staple diet of many larger animals.
Researchers at the Marine Biological Association in Plymouth examined clams in estuaries from Southampton to the Severn and found that males at 17 of 23 sites suffered a condition called “intersex”, where their testes contain both sperm and eggs. In some cases the male sexual organs contained thousands of eggs and up to 60 per cent of clams were affected.
Some scientists fear that the species may become so badly malformed that they will be unable to reproduce. If that causes a significant drop in their numbers, there will be too little food for animals that feed on them, such as plovers, bar-tailed godwits and other wading birds.
Bill Langston, who led the study, said any knock-on effects could be hard to predict. “Invertebrates ... support the whole ecosystem by being at the bottom of the food chain. If something goes wrong at the bottom of the chain, there’s a risk it could be serious for other species higher up,” he said. One concern is that the clams concentrate the chemicals in their flesh, and so other animals eating them could also begin to show signs of feminisation.
The conclusion, published last week in a comprehensive survey of Britain’s flora, suggests that the changing climate has already brought about a rapid and dramatic shift in the country’s plantlife, a trend researchers say will be exacerbated by future warming.
Volunteers working for the Botanical Society of the British Isles and the charity Plantlife recorded more than 200,000 plants in patches four kilometres square around the country and found the number and distribution of one third of all species had changed substantially since an earlier survey in 1987.
Many plants have spread north and west to capitalise on the milder conditions warming has brought, with several species of orchid and fern, such as the bee orchid and hart’s tongue fern, recorded twice as frequently as in the previous survey.
According to the survey, the mean central England temperature for 1987 was 9.05C, compared with a mean of 10.51C in 2004. The report claims that the rising temperatures have caused most disruption to plants with heavy seeds because they are unable to disperse over long distances, and so re-establish themselves far from their traditional habitats.
Studies published in a respected medical journal, the Public Library of Science Medicine, last month accused the pharmaceutical companies of “medicalising” problems such as high cholesterol and sexual dysfunction. The authors of the report highlighted the “restless legs” syndrome, described by GSK as “common yet unrecognised” when it launched its Ropinirole treatment last year.
However David Stout, head of GSK’s pharmaceutical operations, denied the accusations, saying: “You need to talk to the patients. Things like restless leg syndrome can ruin people’s lives. It is easy to trivialise things when you don’t have them. If people did not want the treatments, they would not seek them.”
As a result, doctors will no longer have to take samples directly from the womb for tests. The breakthrough should prevent thousands of miscarriages when the screening system is introduced across the country in a few years, say scientists.
“At present, if doctors want to test a foetus to find out if it has Down’s syndrome, or the blood disease thalassaemia, they have to stick a needle into the womb and remove tissue that surrounds the foetus,” said one of the project leaders, Prof Stan Urbaniak of Aberdeen University. “Unfortunately that carries a small but significant risk of triggering a miscarriage and, given that these tests — such as amniocentesis — are given to tens of thousands of women every year, this causes hundreds of spontaneous abortions.”
The research, carried out by Ofcom, provides the first major snapshot of the regional variations in the availability, take-up and usage of digital TV and radio, fixed and mobile phone services and internet access. It throws up some startling anomalies. For instance, the only exception to the preference for texting over calling is among cellphone users in London, possibly because many have their calls paid for by their employer. — Dawn/The Guardian News Service
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