One of the biggest mysteries in Street Fighter revolves around Blanka. His mutation from a regular boy to the green-skinned beast we see today hasn’t been explained by Capcom very well. At first, they said it was chlorophyll and electric eels that gave him his green skin and electric powers. Then they retconned that and said it was a lightning strike on the plane he was on. If Capcom did their research, however, they would find a more reasonable (if still highly questionable) answer.
The Amazon rainforest where Blanka lived in and grew up is noted for being home to a rich and diverse quantity of minerals, such as gold and iron, and has been looked at, controversially, as the next location for mining. There is one metal, however, that explains Blanka’s “condition” more than any other: copper.
Copper is known for both its ability to conduct electricity and its oxidation process, slowly turning green over time, with the best example of the oxidation process being the Statue of Liberty in New York in which its brown copper exterior slowly turned into the green hue we know today.
So, with this knowledge, we know that Blanka must have been exposed to a large amount of copper to get as green as he is and for him to be able to produce the electricity he creates. Sure enough, there’s proof.
The first factor is his love of tropical fruits. The fruits he eats, and especially pineapple, are all rich in copper, and play a huge role in getting him the large amount of copper he needs to sustain his abilities. We know he eats a lot of pineapple too: his roughened voice is evidence that he has eaten a high amount of bromelain, the reason why a person who eats pineapple tends to have a coarse tongue and throat afterwards. High amounts of it would cause swelling of the tongue and lips and a tingling in the back of the throat, all of which contribute to Blanka’s distinctive speech patterns.
However, Blanka’s diet isn’t the only thing that exposes him to copper. There’s evidence that he works with it as well: the anklets he wears. He wears the anklets because they were the last thing his mother gave him before he involuntarily lived his life in the jungle. Since the anklets must have been much smaller originally, considering he was a child when he had them, the only way they could reach the size they are now is if he added material, and based on what the anklets look like, Blanka must be using fresh copper from time to time to make the anklets fit him. In other words, Blanka is a metalworker. The copper could either come naturally from his surrounding environment or from the wreckage of the crashed plane he was on. Either way, his exposure to it, and his using his bare hands to work with it, caused his skin to turn green and give him the appearance he has today.
Finally, in the original Street Fighter II, Blanka had a more yellow pigmentation to his skin. Yellow skin is a symptom of copperiedus, or copper toxicity, the condition of overdosing on the stuff. Blanka is basically the original metal man, predating Q and Mecha-Zangief by years!