Although we never made it to Yungas, the coca-growing region we planned to visit, due to the cocaleros protest, we interacted with coca quite a bit. We drank it in tea and we chewed it to cope with altitude sickness. Bolivians also use it for hunger and energy (it's a mild stimulant), as well as some other medicinal uses.
Coca, in Bolivian culture, is sacred. Offerings to gods almost always include coca. Religious gestures (such as making the sign of the cross) are sometimes performed prior to chewing coca. With this in mind, it's easy to understand why it is so offensive to Bolivians (and Peruvians) to suggest that coca itself is a drug. You can even buy keychains and bumper stickers that say "Hoja de coca no es droga" (Coca leaf is not a drug).
As Evo Morales points out in his NYT op ed "Let Me Chew My Coca Leaves," the 1961 United Nations Single Convention on Narcotic Drugs placed coca in the same category as cocaine, and said that “coca leaf chewing must be abolished within 25 years from the coming into force of this convention.” Bolivia - under the brutal dictatorship of Banzer - signed onto this in 1976. Well, it's nearly a decade after that 25 year deadline expired, and coca chewing is still around.
Evo points out that plants have compounds called alkaloids. These alkaloids include caffeine, nicotine, and quinine. Then he explains the difference between coca and cocaine as follows:
The coca leaf also has alkaloids; the one that concerns antidrug officials is the cocaine alkaloid, which amounts to less than one-tenth of a percent of the leaf. But as the above examples show, that a plant, leaf or flower contains a minimal amount of alkaloids does not make it a narcotic. To be made into a narcotic, alkaloids must typically be extracted, concentrated and in many cases processed chemically. What is absurd about the 1961 convention is that it considers the coca leaf in its natural, unaltered state to be a narcotic. The paste or the concentrate that is extracted from the coca leaf, commonly known as cocaine, is indeed a narcotic, but the plant itself is not.
If I understand correctly, drinking coca tea provides less of an effect than chewing coca. The reason is the use of llitja or legia, an alkaline agent that is used in chewing. According to the coca museum's website:
The llijta is a preparation made of several types of vegetal ashes, such as quinoa and plantain. Its purpose is to provide an alkaline medium to maximize the action of the alkaloids of the leaf.
When you chew coca, you don't actually chew it. You can see the website linked above for a full explanation, but basically, you form a ball of coca leaves (minus their stems) with the legia in the middle, and you suck on it. I found that I really, REALLY do not like the taste of coca leaves. I don't even like their smell. The tea is mild enough that I enjoy drinking it. It seems you can use legia when you brew coca tea too, but we never did.
The indigenous Bolivians already chewed coca when the Spanish invaded. The Spanish, observing coca's sacred role in Andean cosmology, decided that coca was bad. Then, when the realized that chewing coca would allow the Indians they enslaved to work 40 hour "days" in the mines with no adequate food or rest, they decided that coca must be okay. In fact, at that point they built haciendas to grow as much coca in possible.
The picture below shows an exhibit of a Bolivian miner, together with a representation of El Tio, the god of the mines. Tio, Spanish for uncle, is a devil-like figure that the miners bring gifts of coca (as well as cigarettes and other things) to. By bringing offerings to the Tio, the miners hope for good fortune and safety from harm.
The coca-growing region we were going to visit is not the major cocaine-producing area in Bolivia. In Yungas, the leaves are smaller and Bolivians think they taste sweeter. These leaves are used for chewing and tea. The larger leaves grown in Chapare, a province in the department of Cochabamba, are used for cocaine. Here is an excerpt of an article called "Cocaine and the Economic Deterioration of Bolivia," written in 1986 by Jack Weatherford and printed in the book Conformity and Conflict: Readings in Cultural Anthropology that tells how cocaine is made:
Most of the young men who go to the Chapare do not actually work in the coca fields. The coca bush originated in this area and does not require extensive care. One hectare can easily produce eight hundred kilograms of coca leaves in a year, but not much labor is needed to pick them. After harvesting, the leaves are dried in the sun for three to four days. Most of these tasks can easily be done by the farmer and his family. Wherever one goes in the Chapare one sees coca leaves spread out on large drying cloths. Old people or young children walk up and down these clothes, turning the drying leaves with their whisk brooms.
The need for labor, especially the labor of strong, young men, comes in the first stage of cocaine production, in the reduction of large piles of leaves into a small quantity of pasta, or coca paste from which the active ingredient, cocaine, can then be refined. Three hundred to five hundred kilograms of leaves must be used to make one kilogram of pure cocaine. The leaves are made into pasta by soaking them in vats of kerosene and by applying salt, acetone, and sulfuring acid. To make the chemical reaction occur, someone must trample on the leaves for several days - a process very much like tromping on grapes to make wine, only longer. Because the corrosive mixture dissolves shoes or boots, the young men walk barefooted. These men are called pisacocas and usually work in the cool of the night, pounding the green slime with their feet. Each night the chemicals eat away more skin and very quickly open ulcers erupt. Some young men in the Chapare now have feet that are so diseased they are incapable of standing, much less walking. So, instead, they use their hands to mix the pasta, but their hands are eaten away even faster than their feet. Thousands and possibly tens of thousands of young Bolivian men now look like lepers with permanently disfigured hands and feet. It is unlikely that any culd return to Pocona [a small town in the Andes] and make a decent farmer.
Because this work is painful, the pisacocas smoke addictive cigarettes coated with pasta. This alleviates their pain and allows them to continue walking the coca throughout the night. This pasta is contaminated with chemical residues, and smoking it quickly warps their minds as quickly as the acids eat their hands and feet.
The article goes on, telling how the cocaine manufacturers supply these workers with women, creating an STD problem among the workers as well as the prostitutes. Many of the workers come from remote villages (such as the aforementioned Pocona) which are now suffering horribly from the economic impact of so many people leaving. The cocaine trade also employs people called hormigas (ants), often women and small children, to transport cocaine or the chemicals used to process it.
According to the article, a gram of cocaine sells for $5 in Cochabamba, Bolivia, but sells for over $100 in the U.S. I'll admit, I don't know what cocaine sells for now or what it sold for in 1986 in the U.S. or anywhere else. But going with these numbers, and other numbers given in the 1986 article, for the gram of cocaine that sells in the U.S. for $100, the farmer received a penny. By my math, that means a farmer received maybe $20 per hectare of coca, double what can be earned by growing papaya. (On my trip, I bought a plastic bag of coca leaves, maybe 5 oz, for 5 Bolivianos. That's a little under $1.) The pisacocas were paid $3 per day, three times what they would make doing other work. The person smuggling the cocaine out of Bolivia was paid $5000 for moving a shipment worth $5 to $7 million. There are Bolivians who get rich by Bolivian standards from the cocaine trade, but there are far more who suffer.