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         The perils of counterfeit drugs go way beyond being ripped off by dubious online pill-pushers. The World Health Organization (WHO) estimates that 50 per cent of all medicines sold online are worthless counterfeits. In developing nations fake pills may account for as much as 30 per cent of all drugs on the market. Even in the developed world, 1 per cent of medicines bought over the counter are fakes.

        Some key events illustrate the risk these pose. In Nigeria, 2500 children died in 1995 after receiving fake meningitis vaccines. In Haiti, Bangladesh and Nigeria, around 400 people died in 1998 after being given paracetamol that had been prepared with diethylene glycol – a solvent used in wallpaper stripper. The fakers are nothing if not market-aware: in the face of an outbreak of H5N1 bird flu in 2005, they began offering fake Tamiflu.

         What can be done? The WHO coordinates an umbrella body called the International Medical Products Anti-Counterfeiting Taskforce (IMPACT), an industry initiative that issues alerts when it finds anomalies in the medicine supply chain. Such events include sudden drops in wholesale prices, hinting at fakes coming onto the market, or the mimicking of anti-counterfeiting features on packaging, such as holograms or barcodes, says Nimo Ahmed, head of intelligence at the UK’s Medicine and Healthcare Products Regulatory Agency.

New Scientist, 10 July 2010, p. 18. Adaptado.

Considere 4 frascos, cada um contendo diferentes substâncias, a saber:

Frasco 1: 100 mL de H2O(l)

Frasco 2: 100 mL de solução aquosa de ácido acético de concentração 0,5 mol/L

Frasco 3: 100 mL de solução aquosa de KOH de concentração 1,0 mol/L

Frasco 4: 100 mL de solução aquosa de HNO3 de concentração 1,2 mol/L

A cada um desses frascos, adicionaram-se, em experimentos distintos, 100 mL de uma solução aquosa de HCl de concentração 1,0 moI/L. Medindo-se o pH do líquido contido em cada frasco, antes e depois da adição de HCl(aq), pôde-se observar aumento do valor do pH somente

No losango ABCD de lado 1, representado na figura, tem-se que M é o ponto médio de N é o ponto médio de. Então, DM é igual a

The Impact of the Gulf Oil Spill on the U.S.

www.freewebs.com/mathewstolte/oilspills.html. 21/06/2010

      Although the oil has been pouring into the Gulf of Mexico for months, the consequences of this larger than ever environmental disaster have yet to be fully examined and determined. Scientists and researchers have started to put together some of the puzzle pieces, and the impact of the Deepwater Horizon oil spill are likely to be big.

      North Americans will have fewer choices on the store shelves. The Gulf of Mexico is a huge shipping lane through which products of all shapes and sizes come into North America. From toys to clothes to cars to building materials, you may find that the selection at your local store begins to shrink as shipping lanes slow down as a result of the oil spill.

      Whether you’re taking a vacation or hoping to walk along the shore, you may be disappointed. Many beaches in the U.S.A. are now closing as clean-up efforts on removing oil slick from the sands. But the impact may be felt for quite some time as oil continues to wash up on shore.

      Many wildlife animals will be impacted by the oil spill. Oiled birds, otter, bald eagles, pelicans, turtles, fish, and dolphins are already washing up on shore, making the beach sights less than palatable for someone looking to see some pristine nature.

      Over time, molluscs like clams incorporate calcium into their shells throughout their lifetimes. But the heavy metals like nickel and vanadium from the petroleum industry and the resulting oil spill may be incorporated into the shells of these creatures. As other wildlife consumes these clams, they incorporate the toxins into their bodies, and on it goes as the heavy metals bio-accumulate in the food chain. This could have serious, long-term consequences for human health. 

      Environmentalists have been working on restoring the populations of oysters by reseeding certain reefs to boost their numbers. The Gulf of Mexico has been home-working on some of these projects, but with the massive oil spilling into that environment, the oysters could soon become tainted with chemicals, making them unsafe to eat.

      The Gulf of Mexico is also a nursery for species like shrimp that grow up in the estuaries. The oil that is taking over this natural environment will choke out the plants that make the estuaries so nutritious to shrimp. 

      According to the National Weather Service, a hurricane like Hurricane Katrina could have a devastating impact on New Orleans. Researchers expect 15 named storms to develop into 8 hurricanes, and with a well-placed hurricane, the oil could be pushed onto New Orleans shores, further impacting the already devastated region.

Adapted from http://www.thenewecologist.com (21/06/2010)