The European Parliament, in agreement with the European Council, now obliges national authorities to search for alternative methods of research and reduce the pain inflicted on animals used in testing, while not impeding successful scientific research.
Under the new law, the use of primates in scientific testing will be limited by the European legislative body. A limited number, primarily ouistitis and macaques monkeys, will still be used, as they are needed for research on new drugs for neurodegenerative illnesses such as Alzheimer's.
The new law, however, strictly bans the use of other primates such as chimpanzees, bonobos, gorillas, and orangutans. 
Ouistitis, which is the French name for marmosets, are small-sized monkeys which live to the south of the Amazon River in Brazil. Macaques are the most widespread primates living in many regions, including Japan, Afghanistan, and North Africa.
Bonobos are big apes inhabiting the south of the Congo River bank, and are an endangered species.
The European Council requires the national governments of the 27 member states of the European Union to secure inspections on at least 33 percent of the laboratories that use animals. As the EU executive, the European Commission will oversee national inspection authorities.
Animal testing has always been controversial, although on the positive side, animal testing has allowed research of medicines for illnesses such as cancer and AIDS.
Some scientists believe that animals are suitable for testing as they are similar to humans in how they react to drugs. Many negative side effects of new drugs can only be detected through animal testing, before they hit the market.
On the other side, many animals suffer and can be harmed or killed in the testing process—sometimes in vain. The reason for this is that many of the tested drugs never appear on the market. Some experts also say that animal testing is not reliable, as sometimes animals react differently from humans.
