Medicijngebruik bedreigt visbestanden.*
Uit recent onderzoek in Amerika blijken grote rivieren en meren veel restanten van medicijnen te bevatten. De hoeveelheden zijn (nog) zodanig klein dat ze voor de mens in drinkwater geen problemen zullen geven, doch geen enkele wetenschapper weet of een levenslange blootstelling zonder gevaar is. Voor vissen ligt de situatie ook anders. Bijv. voor restanten van anticonceptiepillen zijn vissen heel gevoelig. Sommige mannelijke vissen beginnen al vrouwelijke voortplantingsweefsels te vormen. De levenscyclus van schaaldieren kan danig van slag raken door restanten serotines van anti-depressiva.
Pharmaceuticals contaminating public water supplies; anti-seizure meds found in Lake Michigan
Pharmaceuticals, including birth-control hormones and anti-seizure medications, have been found in Lake Michigan and public water supplies, according to a new study. The study was jointly sponsored by the U.S. Fish and Wildlife Service and the American Pharmacists Association.
The water system examined serves more than a quarter-million people in Grand Rapids, East Grand Rapids, Walker, part of Kentwood, Ada, Cascade and Grand Rapids townships, as well as parts of Ottawa County.
In Lake Michigan, near the Grand Rapids water filtration plant, tests found traces of Tylenol, ibuprofen, hormones from birth-control pills, and some beta blockers in heart medication, Department of Environmental Quality toxicologist Amy Perbeck stated.
In treated water at the Grand Rapids water filtration plant, scientists found traces of the anti-seizure medication carbamazepine, she said. The drugs were measured in parts per trillion -- too small to be considered a "therapeutic dose" in humans, said Perbeck.
"Someone would have to drink 17,000 gallons of water to get the concentration they would get in one ibuprofen pill," she said.
However, Perbeck expressed concern about the effect of birth-control hormones on fish, stating "The fish are constantly exposed to hormones." In some parts of the country, scientists have found male fish with female ovarian tissues.
Professor Rick Rediske, senior program manager at Grand Valley State University's Annis Water Resources Institute, pointed out even the smallest amounts of pharmaceuticals, as well as substances such as anti-bacterial soap, could harm aquatic life.
He referred to shellfish, which excrete serotonin to signal they are ready to mate. Trace amounts of serotonin in anti-depressants such as Prozac could send false messages.
"It can mess up part of their life cycle," he said, "It's very complicated when there are very low levels of exposure over a long time."
While some scientists claim the drugs are too diluted to harm humans, they acknowledge no one knows the dangers of lifetime exposure.
(Juli 2007) (Opm. De situatie hier
zal niet veel verschillen van die in Amerika met het gevolg dat binnen
afzienbare tijd het voor ons zo belangrijk voedsel, vis er niet meer zal zijn.
De oplossing is simpel gebruik alleen medicijnen als ze echt nodig zijn, en dat
is niet vaak. Medicijnen zijn niet anders dan voor het lichaam giftige stoffen.
Gezonde voeding daarentegen kan zonder bijwerkingen of andere gevolgen de meeste
problemen oplossen kijk maar eens bij het ABC.)