Palm oil itself is vegetable-based and animal-free, so why do many vegans consider products which contain it to be unsuitable to purchase/consume?
Orangutans are endemic to Borneo and Sumatra. Borneo is divided amongst three nations: Malaysia, Brunei, and Indonesia. Palm oil production is the biggest cause of Orangutan habitat loss. It's the cause of the deaths of 2,500 of the world's 50,000 or so of these creatures per annum according to a UN report.
According to the February 2013 issue of VegNews.
This habitat destruction also affects other creatures such as proboscis monkeys, pygmy elephants, otters, pigs, and crocodiles.
There's a BBC report on palm oil which points out (amongst other things) that palm oil residue is poisonous to dogs.
Because several ecosystems are being destroyed to fuel the oil palm industry. It might be animal-free, but it is not cruelty-free.
The oil palm agribusiness is devastating the rainforest in Southeast Asia:
The two largest oil palm-producing countries—Indonesia and Malaysia—are located in Southeast Asia, a region with numerous endemic, forest-dwelling species. Oil palm producers have asserted that forests are not being cleared to grow oil palm. Our analysis of land-cover data compiled by the United Nations Food and Agriculture Organization suggests that during the period 1990–2005, 55%–59% of oil palm expansion in Malaysia, and at least 56% of that in Indonesia occurred at the expense of forests.
This is already causing extinction of endemic species:
Over Borneo and Sumatra as a whole, illegal logging has led to huge declines in orangutans and other wildlife. Where forests are converted to plantations of oil palm or other crops, the consequences are even more serious, with many orangutans starving.
The Sumatran orangutan is classified as Critically Endangered by IUCN. Since 1900, the number of Sumatran orangutans is thought to have fallen by about 91%, with a rapidly accelerating loss towards the end of the 20th century.
By keeping their business away from the developed world, oil palm companies seek to reduce their operation costs by using slavery, child labor and unfair trade:
In the report, Amnesty alleged that children aged from eight to 14 were carrying out dangerous work without safety equipment, were exposed to toxic pesticides and regularly carried sacks of palm fruit weighing 25kg.
There's also a strong backlash against the sector's PR stunts:
The Malaysian government recently announced that it will ban the conversion of ‘protected forests’ and ‘forest reserves’ to oil palm plantations, and will only allow areas zoned for agriculture to be developed. But it provides little optimism for two reasons. First, it is unclear what type of land has been or will be designated for agriculture. Second, immediately following the above announcement the Malaysian government also declared that it has acquired land in Aceh, Indonesia (45 000 ha), Papua New Guinea (105 000 ha) and Brazil (100 000 ha) for oil palm development.
There are several reasons:
First, many vegans are concerned for the planet and the environment. A large proportion of deforestation in recent years has been caused by the expansion of oil palm fields, partly provoked by the demand for biofuels. So, boycotting palm oil is a way to reduce or express resistance to destruction of the environment.
Second, there was a campaign by Rainforest Action Network. In this campaign a video called "AMAZING! Orangutan asks girl for help in sign language" - which then went viral - was showing a causal connection between consumption of palm oil and extermination of orangutans. So avoiding palm oil may theoretically help to save animals' lives.
We should note that orangutans are not the only victims of deforestation, since eliminating forest causes the death of thousands species and the loss of biodiversity. It's understandable that RAN focused on one species to create a more emotionally provocative, impactful campaign.
Finally, palm oil contains about 50% saturated fats, which may increase the risk of cardiovascular diseases when consumed. So vegans who are concerned about health may avoid palm oil for that reason.
While palm oil is praised for its bland taste (thus not affecting the taste of the food), oxidative stability and therefore long shelf life, there are several grave problems with it, mainly of ecological character, but some also related to health.
To speculate why, even though it is plant-based ingredient, vegans shun palm oil, I would say that vegans, in general, are often not only interested in the nature of their food, but also in the effects the products they consume have on their bodies and the environment.
Health: Palm oil is high in saturated fats (3-4x the amount compared to rapeseed or sunflower oil) which raise cholesterol levels and are in general not considered very healthy.
Environment: This is actually the main reason why I avoid it, if possible. Production of palm oil, more than most of the popular oils, takes its toll on some of the most critically endangered ecosystems on our planet - rainforests. This threatens many animals, such as orangutans and Sumatran tigers. It is one of the causes of deforestation.