A mix of cultures
Contamination, the mixing of cultures, is extremely evident in Strasbourg, France. The small city has switched nationalities five times between French and German. After being in Heidelberg, Germany for a day, and Paris, France for a week, I can say that Strasbourg seems to be almost as much German as it is French. The big question about cultural contamination is, is it good or bad? I think it is somewhere in the middle.
It is good to be open to mixing cultures. It's good to learn from each other and gain from each other's achievements. The world and technology would have developed a lot slower if people from different cultures did not work together and build off of each other's ideas. It's also good to experience each other's practices, customs, foods, religious celebrations, and etc. These kind of things display the commonalities between each other because all cultures do these things, even if they do them in different ways. It improves our awareness that we are all humans with the same desires who deserve the same respect and rights.
But it is also good to preserve individual cultures. We would not want the world to become one homogeneous place. The world's diversity is a wonderful thing. It helps us appreciate the creativity of the human mind. We would not want to over-contaminate the world.
Strasbourg is a great place to visit. It is really neat to see German and French style, architecture, food, and so on, combined to make one new culture. But I am glad there are still places like Heidelberg and Paris where German and French culture can be seen separately and fully.