Palm oil's contribution to the United Nations sustainable development goals: outcomes of a review of socio-economic aspects

One of the characteristics of oil palm plantations is their high yield in terms of amount of oil produced per unit of cultivated area, with two different types of products that can be extracted from the fruit of oil palm: palm oil from the fruit and, in smaller quantities (about 10%), palm kernel oil from the seeds of the fruit, with an average yield of 3–4 tonnes per hectare of palm oil and 0.5 tonnes per hectare of palm kernel oil (Azhar et al 2017, FAOSTAT 2021). This is up to 10 times more than any other commonly used vegetable oil (Khatun et al 2017), thereby requiring less land than other oil crops for the same amount of product obtained. This characteristic is confirmed by Food and Agriculture Organization Corporate Statistical Database (FAOSTAT) data that indicate for 2019 that although oil palm cultivation accounts for over 35% of global vegetable oil production, it occupies about 28 million hectares, which is less than 10% of the land used for vegetable oil production worldwide (FAOSTAT 2021).

The annual global production of palm oil in 2018 was around 80 million tonnes—this includes the production of both palm oil (90%) and palm kernel oil (10%)—an increase of +55% compared to production in 2010 (51.3 million tonnes) (FAOSTAT 2021). Palm oil production and use is, therefore, growing steadily (Khatun et al 2017, FAOSTAT 2021), and is expected to increase even further (Corley 2009) given the steady increase in demand for food and energy from the world's population, which is forecast to top about 10 billion people by 2050 (IFAD 2014, FAO 2015). Currently, Indonesia and Malaysia are the largest producers of palm oil, accounting for about 88% of global production with 40.6 and 19.5 million tonnes, respectively, in 2018 (FAOSTAT 2021), and host the majority of oil palm plantations with 14.7 and 5.2 Mha, respectively, although other tropical areas, including Thailand, Central and South America, and West Africa, are recently and rapidly expanding their oil palm plantations.

The increasing demand for palm oil from the international market, together with the growing public attention as to its impact on the environment and society, has prompted the various players in the palm oil production chain to raise awareness regarding the need to engage in more sustainable production methods than those conventionally used. This new awareness has led to the development of a series of certification schemes and protocols, which have been expanded over the years to include both environmental and socio-economic principles and criteria for the sustainable production of palm oil. Among the high number of standards and protocols covering sustainable agri-food production or the protection of habitats and biodiversity, some can be specifically applied to sustainable palm oil production (Yaap and Paoli 2014, McInnes 2017, Schlösser and Walter 2020), addressing its environmental and socio-economic aspects, either directly or indirectly (table 1).

According to RSPO data (RSPO 2021)—one of the most comprehensive certification schemes as reported by a number of studies that analyse and compare the main sustainability standards for agricultural production (Yaap and Paoli 2014, McInnes 2017, Schlösser and Walter 2020)—currently 4.36 million hectares of the 28 million cultivated with oil palm worldwide are certified as sustainable, accounting for a total of 17.6 million tonnes of palm oil and corresponding to 19% of the global production of palm oil.

The literature review showed that many studies agree that oil palm cultivation contributes positively to the socio-economic development of local communities, irrespective of the country of production or the approach used, with a substantially positive impact on poverty reduction and economic growth in rural areas (Susila 2004, Obire and Putheti 2010, Schrier-Uijl et al 2013, Kamalrudin and Abdullah 2014, Edwards 2018, Ahmed et al 2019). The effects of poverty reduction and economic growth are even greater for small producers who also manage to grow other crops in association with oil palm (Feintrenie et al 2010, Fu et al 2010, Kremen et al 2012, Azhar et al 2017).

In developing countries, the poverty rate of communities engaged in oil palm cultivation tends to be lower than the national average (Etuah et al 2020), with examples in Indonesia (Susila 2004, Dradjat 2012, Alwarritzi et al 2015, Edwards 2018, Etuah et al 2020) and Nigeria (Ayodele 2010, Adesiji et al 2016, Etuah et al 2020). One study in particular (Edwards 2015) shows how a 10% increase in the land area dedicated to oil palm cultivation produces a 10% reduction in the poverty rate, leading to a reduction in the poverty gap between various social classes (Edwards 2015, Pacheco et al 2017), with short-term poverty reduction effects being greater on large-scale plantations than on small-scale ones (Edwards 2015). Edwards (2019) reports that about 2.6 million Indonesians living in rural areas have been lifted out of poverty in this century thanks to the economy linked to palm oil production (Meijaard and Sheil 2019). Numerous initiatives incentivizing oil palm cultivation are promoted locally by governments, especially in Asia (Indonesia, Malaysia, Thailand, etc) and sub-Saharan Africa (Ghana, Nigeria, Cameroon, Côte d'Ivoire, Benin, etc), as a key tool to alleviate poverty, particularly in local communities in rural areas (Susila 2004, Rist et al 2010, Syahza et al 2011, Ofosu-Budu and Sarpong 2013, Sinaga 2013, Nkongho et al 2014, Oosterveer 2014, Potter 2015, Pirker et al 2016). In many developing countries, oil palm is considered a highly profitable crop—it is, in fact, defined as a cash crop since it is grown mainly to be sold for profit, as opposed to staple crops intended as subsistence crops that are grown as food mainly for the producers' family or to feed their livestock—outstripping any other crop in terms of productivity and labour required (Feintrenie et al 2010, Rist et al 2010, Harianto 2019). Oil palm can be considered the most efficient oil crop since it is able to produce the same volume of vegetable oil on less than 20% of the area required for other oil crops, such as soybeans, rapeseed and sunflowers (Persey et al 2011, Meijaard et al 2020). Moreover, from the labour resource perspective, its cultivation only requires, on average, 0.2 man-years per hectare (Corley and Tinker 2016, Jelsma et al 2017).

What makes palm oil production one of the most desirable and accessible sources of income, with a positive impact on socio-economic development and poverty reduction, is its higher profitability and its low labour intensity (Persey et al 2011, Jelsma et al 2017, Grepalma 2020). Some studies have shown that oil palm farmers in Guinea have more stable incomes than farmers who do not grow oil palm or other cash crops (Balde et al 2019, Qaim et al 2020); furthermore, smallholders whose main source of income comes from oil palm cultivation have better financial and well-being indicators, as well as lower malnutrition rates than smallholders who do not cultivate oil palm (Dayang Norwana et al 2011, Budidarsono et al 2012).

Nevertheless, some publications underline both positive and negative effects (McCarthy and Cramb 2009, Cramb and Curry 2012, Schrier-Uijl et al 2013, Li 2015, 2018, Meijaard and Sheil 2019, Santika et al 2019, 2020). Although oil palm cultivation has produced positive economic returns, good employment levels and a general improvement in access to social services for smallholders and their families (Dayang Norwana et al 2011, Schrier-Uijl et al 2013, Ohimain et al 2014, Muhammad et al 2019), land-use change due to the expansion of palm oil, particularly for biofuel production in Malaysia, has prompted many local communities and ethnic groups to move away from their traditional lifestyles that were historically dependent on the natural resources and ecosystem services provided by natural forests (Dayang Norwana et al 2011). In particular, one study (Santika et al 2019) shows that the social impacts of oil palm plantations cannot be uniformly defined, but they are highly dependent on a number of variables, such as site-specific characteristics and socio-economic conditions of local communities prior to the start of cultivation (Meijaard and Sheil 2019, Santika et al 2019). Specifically, communities engaged in oil palm cultivation located in villages with low forest cover, accustomed to purchasing subsistence goods on the market, improved their socio-economic well-being through the development of plantations, compared to villages without oil palm (Santika et al 2019). The opposite case was observed in plantations developed in remote villages with higher forest cover, where the livelihoods of the local communities depended on direct cultivation or the utilization of forest products and services. These communities were forced into a change in their lifestyle as opposed to neighbouring communities that had not engaged in oil palm cultivation (Santika et al 2019, 2020). In general, the most consolidated, long-established communities in the area tend to resist the temptation to abandon traditional practices and culture in exchange for the stable income that palm oil production can provide, since land-use change in favour of palm oil plantations raises concerns especially with regard to maintaining land ownership and security in the land regulation system (Dayang Norwana et al 2011). One study points out that small farmers risk being impoverished by having to sell their land, which may be required for oil palm expansion. For this reason, smallholders should be supported by national legislation (Rist et al 2010, Nkongho et al 2014) through the development of a system that incentivizes and regulates the renting rather than the sale of land (Rist et al 2010).

The positive or negative impact of oil palm cultivation also depends on the social groups involved. The social and economic benefits of oil palm are usually limited to particular social groups, including, for example, smallholders who add oil palm to their farming systems, thereby diversifying the crop systems (Li 2015). Different effects in social and economic terms can also be produced depending on the relationship between the smallholders and the large companies managing the oil palm plantations (Castellanos-Navarrete et al 2019). For example, oil palm smallholders (plots averaging 2 ha) linked to large companies by supply contracts are more vulnerable to impoverishment, mainly due to the low income they receive, which, in many cases, is not sufficient to cover farm management costs and basic household expenses (Li 2018). As a result, these smallholders run the risk of losing their land and hence the ability to sustain their livelihood, and this, in turn, leads to economic and social decline (Cramb and Curry 2012, Li 2015, Cramb and McCarthy 2016). In contrast, oil palm cultivation managed by independent smallholders (ISHs) is more profitable than the above-described option, although it requires a significant initial capital outlay. It should, however, be taken into account that the minimum size of a monoculture plot should be 6 ha to guarantee productivity and meet family needs (Li 2018).

Adiprasetyo et al (2019) showed that, in general, perceived economic and environmental benefits are greater for farmers who adopt sustainable palm oil production than for conventional farmers. Specifically, an analysis carried out in Kalimantan (Indonesia) shows that the application of RSPO certification does not bring about a reduction in poverty but could be related to a deceleration in the growth of poverty rates (Morgans et al 2018). According to Azhar et al (2017), most of the certified sustainable palm oil in global markets comes from large plantations and only a small part from smallholders; this is mainly due to the high costs of certification, which are not always offset by higher selling prices. As a result, although smallholders apply traditional practices that are often more biodiversity-friendly, they are not identified and acknowledged as being 'sustainable'. Some certification schemes (RSPO and MSPO) are seeking to make certification more accessible for smallholders (Meijaard and Sheil 2019, Yap et al 2021) with the introduction in 2019 of a specific standard (RSPO ISH standard) that aims towards greater inclusion of smallholders in the RSPO certification system through a simplified approach for the production of sustainable palm oil also by small independent farmers.

Assessing the effects of palm oil production in relation to SDG 2 is a particularly important issue given the fact that current estimates show that almost 8.9% of the world's population (690 million people) suffer from hunger and malnutrition (FAO 2020) and that the majority of the world's undernourished population is in Asia (381 million) and Africa (250 million), which are the countries with the most oil palm cultivations.

Oil palm is considered a primary crop for many countries from an economic perspective, while the effects on food security can be positive or negative (Santika et al 2019, 2020). Some studies maintain that the presence of oil palm crops helps to guarantee food security (Ayodele 2010, Khatun et al 2017) and alleviate malnutrition (Budidarsono et al 2012, Khatun et al 2017). Palm oil is also a key element in the diet of many local populations. An example is Thailand where it accounts for approx. 75% of edible oil energy intake (Kosulwat et al 2006, Jensen et al 2019) thus representing a fundamental commodity for food security (Rewtarkulpaiboon 2015, Khatun et al 2017, Jensen et al 2019) due to the improvement in calorie intake deriving from its consumption. Moreover, palm oil contributes also to the improvement in the nutrition of local populations as a result of rising incomes, prompting increased spending on food, which has effectively also weakened the role of subsistence food production (Sibhatu and Qaim 2018, Sibhatu 2019, Qaim et al 2020). According to a series of studies carried out in Southeast Asia, earnings from oil palm cultivation contribute to improved food security in smallholder households by providing the families with greater economic means to purchase food (Feintrenie et al 2010, Rist et al 2010, Cramb and Curry 2012, Obidzinski et al 2012, Sibhatu 2019, Qaim et al 2020). Also, in Africa, studies in Guinea (Balde et al 2019, Qaim et al 2020) and Ghana (Ahmed et al 2019, Qaim et al 2020) report that smallholders cultivating oil palm have greater food security than those who do not, due to higher incomes that enable them to spend more on food purchases.

However, the positive effects of oil palm cultivation in terms of increased food security are particularly good for small independent farmers who have the opportunity to combine oil palm with other crops including rice, rubber and fresh vegetables in a sustainable intercropping system (Fu et al 2010, Kremen et al 2012, Li 2015, 2018, Azhar et al 2017, Grepalma 2020), thereby ensuring a varied diet and direct access to different types of food. In contrast, smallholders who adopt the monoculture oil palm system are forced to rely on the market for food purchases, abandoning subsistence farming and consequently generating increased household expenditure for the procurement of food, leading to a drop in food security for the whole family (Sinaga 2013, Alwarritzi et al 2015). A study conducted in Indonesian villages showed that where oil palm is the main source of income, malnutrition rates are lower than in villages where it is not cultivated (Budidarsono et al 2012). However, increased income does not always lead to better levels of food security, which also depends on many other factors, such as the availability of food or the efficiency of markets (Mingorría et al 2014, Alwarritzi et al 2015, Pacheco et al 2017, Elmhirst et al 2017a, Hamann 2018, Castellanos-Navarrete et al 2019).

Furthermore, while in some cases the production of palm oil improves the socio-economic conditions of smallholders and hence their food security and access to food at the local level, it could also pose a food security problem, mainly due to the risk of entire agricultural areas being converted into monoculture oil palm plantations (Pacheco et al 2017, Sharma et al 2019). A possible solution could be sustainable intensification as a compromise to avoid further expansion of oil palm in the future (Manik et al 2013, Elmhirst et al 2017b, Sharma et al 2019). Along the same lines, some studies highlight the controversial role, as regards food security, of oil palm cultivation, especially in relation to biofuel production (Meijaard and Sheil 2019), which could increase the risk of competition between land uses and encourage land grabbing (Bassey 2016, Onoja et al 2017). Another study maintains that the increase in land converted for oil palm cultivation in Indonesia could lead to rapid urbanization of the areas surrounding the plantations, which, together with the migration that often accompanies such expansion, could pose a risk to the food security of smallholders and their families (Budidarsono et al 2013). This finding is confirmed by the fact that, according to some publications, indigenous populations are the most heavily affected by oil palm expansion in terms of food security (Manik et al 2013, Mingorría et al 2014, UNICEF 2016), since they are more exposed to changes in their eating habits, switching from traditional high-protein diets (meat and fish) to diets based on less nutritious foods. This is mainly due to the considerable commitment, in terms of time, required for the smallholders to cultivate the oil palm to the detriment of subsistence farming, thereby creating more dependence on the market not only for the sale of palm oil but also for the purchasing of food. These aspects mainly impact women (Julia and White 2012, Elmhirst et al 2017a) and children (UNICEF 2016).

From the standpoint of access to social benefits, several studies maintain that oil palm cultivation increases the possibility of access to healthcare for smallholder families, chiefly due to the increased economic means at their disposal thanks to their earnings (Feintrenie et al 2010, Rist et al 2010, Cramb and Curry 2012, Varkkey 2012, Adebo et al 2015, Alwarritzi et al 2015, Potter 2015, Elmhirst et al 2017b, Sibhatu 2019, Qaim et al 2020). In particular, a number of studies (Syahza et al 2011, Gatto et al 2017, Edwards 2019) have found that the widespread cultivation of oil palm has led, indirectly, to the improvement of health facilities in Indonesia, and this is a key element in ensuring more equitable access to the country's national health services (Efendi 2012, Budidarsono et al 2013, Pacheco et al 2017, Grepalma 2020). Analysing a sample of 516 villages throughout Indonesia, 60% of which were totally dedicated to oil palm cultivation, the study found that oil palm-dominated villages perform well on many development indicators, such as schools, roads, incomes, access to electricity and access to health facilities. A survey (Acosta and Curt 2019) conducted in a forested area in Papua (Indonesia) confirmed the major social benefits that oil palm cultivation brings, but also noted the irreversible loss of benefits provided by forests. However, a study by Santika et al (2019) points out that the effects of the palm oil industry on well-being are not always equally distributed among Indonesians and can depend on the site-specific characteristics or on the pre-existing socio-economic situation of the villages prior to the development of oil palm cultivation. In some villages that cultivate oil palm, there is a lower rate of improvement in social and environmental well-being than in villages that do not, irrespective of the location and basic livelihoods of the community. In addition, many communities suffer negative impacts on general well-being due to certain negative factors such as the exploitation of labour and work alienation (Manik et al 2013, Mingorría et al 2014). Attempts are made to overcome the above-described problems by applying sustainability certification standards, reason for which several studies have been dedicated to a comparison of the impacts of various sustainable production approaches on health and well-being (Yaap and Paoli 2014, McInnes 2017). One study in particular (Morgans et al 2018) compared the health impact of RSPO-certified and non-certified plantations in some villages in Indonesian Borneo. Given the fact that health facilities per capita in the areas surrounding the plantations, both certified and non-certified, have been progressively decreasing since 2000, while populations in the villages surrounding the plantations have been growing, one study determined that sustainability certification did not actually increase access to healthcare in relative or absolute terms, but simply slowed down its decline (Morgans et al 2018).

Santika et al (2020) also assessed the impact of RSPO certification on well-being in Indonesian villages by monitoring changes in 18 indicators of socio-economic and socio-ecological well-being. The study shows that the connection between RSPO certification and well-being at village level varies depending on the location and basic nutritional conditions of the village prior to full implementation of the certification principles and criteria. The impacts are positive in villages where the majority of the community was already purchasing staples on the market prior to certification; whereas RSPO certification has been associated with negative results in rural villages oriented towards subsistence farming. Additionally, the same study maintains that improvements in well-being were more evident in locations where plantations had been certified for a longer time, confirming that some benefits of sustainability certification tend to emerge in the long term. Some studies in Indonesia (Lee et al 2020) and Malaysia (Nambiappan et al 2018) show that sustainability certification schemes, such as RSPO and MSPO, contribute in the short term to environmental conservation but have a limited impact on rural development. So further analyses of the long-term impacts of certification on the environment and communities will have to be carried out.

The negative aspects emerging from the analysis of the studies include the impact that the conventional approaches to oil palm production have on the health of the plantation workers (Ahmed et al 2019, Castellanos-Navarrete et al 2019) due—particularly in Indonesia—to the use of hazardous chemicals, to the heavy workloads, occupational accidents and the inadequate healthcare provided by the companies (Moreno-Peñaranda et al 2015). Specifically, female workers are more exposed to serious health risks due to pesticides (Li 2018). Schrier-Uijl et al (2013) also identified an additional environmental—but also human—health risk in the burning of plant biomass to clear land for oil palm cultivation. There are many initiatives in palm oil producing countries that promote the well-being of citizens: one example is in Guatemala where a significant increase in well-being has been achieved through investment in health and food security programmes, medical care in hospitals, medical services on plantations available to workers and to members of the community, community medical programmes, ambulance services, as well as health and nutrition training programmes (Grepalma 2020).

Guaranteeing inclusive and equitable quality education and promoting lifelong learning opportunities for all individuals is a key part of the Sustainable Development Agenda, which promotes quality education at all levels (UN 2015). Education is considered an essential factor in improving agricultural production, particularly with a view to sustainability and social equity (Li 2018, Furumo et al 2020). It has, in fact, been demonstrated that a high level of literacy enables a better understanding and subsequent improvement of the agricultural practices related to the production of palm oil, including the implementation of innovations and technologies (Ibitoye et al 2011, Adesiji et al 2016). Two socio-technical analyses of palm oil plantations in Indonesia show that the people working in the production of palm oil tend to be poorly educated or to have an educational background unrelated to the agricultural sector (Alwarritzi et al 2015, Sitepu et al 2020); this condition slows down the transition towards sustainable production (Sitepu et al 2020). The creation of oil palm plantations is often followed by the development of a range of infrastructures such as roads, healthcare structures and, above all, educational facilities (Feintrenie et al 2010, Budidarsono et al 2012, 2013, Obidzinski et al 2012, Schrier-Uijl et al 2013, Pacheco et al 2017, Grepalma 2020, Qaim et al 2020). The majority of the large palm oil companies in Malaysia are involved in building schools to provide education for the children of their workers, thereby generating a positive impact on the standard of living of employees and their families (Dayang Norwana et al 2011). Two major studies (Santika et al 2019, 2020) have also correlated the impact of oil palm plantations with the habits of the villages in procuring staples: from these studies it emerged that where villages were already market-oriented in the procuring of staple foods, access to infrastructure, including education and health, tends to be better than in villages oriented towards obtaining the staples directly. Sustainable palm oil production pays particular attention to educational processes (Lee et al 2020). In particular, Yaap and Paoli (2014) observed that four of the most important standards in the promotion of sustainable palm oil in Indonesia—RSPO, ISPO, ISCC and SAN—require palm oil companies to guarantee access to education for children living in the areas surrounding the plantations. However, one study indicates that, often, such support for improving children's access to education is offered by palm oil companies to the local population to partially compensate for and offset the potential negative consequences that might result from the land-use change that occurs as a result of the creation of the oil palm plantations (Acosta and Curt 2019). The same study points out that the compensation provided to the local population by plantation companies in terms of additional benefits (e.g. education and health) should always be greater than the benefits lost as a result of the planting of the oil palm crops (Acosta and Curt 2019). Another publication highlighted that in Indonesia, due to the development of the palm oil sector, manufacturing companies often provide service access to primary and secondary schools for their employees' children, also facilitating transport, particularly to educational facilities located in remote rural areas (UNICEF 2016). But the same study also points out that sometimes the quality of the education provided is below public standards because teachers are poorly paid and not well trained (UNICEF 2016).

Most studies addressing gender issues connected with the production of palm oil have been conducted in Indonesia and Africa. For example, Li (2015) applied a gender perspective to analyse the impacts of oil palm on men and women from different social groups. The two main models of oil palm cultivation were taken into consideration: large-scale plantations employing both casual and permanent workers, and small-scale plots, both independent and linked to large palm oil companies. Some of the impacts on women included the loss of the land they used for subsistence agriculture (Li 2015, Moreno-Peñaranda et al 2015), greater difficulty in acquiring plots of land for cultivation, labour vulnerability on plantations (Li 2015, Elmhirst et al 2017a, 2017b, Castellanos-Navarrete et al 2019) and the limitation of gender-related employment rights, such as maternity leave and breaks for breastfeeding (UNICEF 2016). Only in the production model with small independent plots do women retain some rights such as taking part in the decision-making of agricultural management, sharing benefits with their husbands and having equal land ownership rights (Li 2018).

In general, male and female workers in oil palm cultivation often have different responsibilities: men are mostly employed for harvesting activities, while women are employed for sporadic tasks, such as weeding or the application of fertilizers, but they are forced to accept more precarious conditions and lower wages than their male counterparts (Li 2015, Elmhirst et al 2017a, 2017b). Some studies (White and White 2012, Li 2015, Elmhirst et al 2017a, 2017b) highlight gender differences even more, underlining that women are generally excluded from taking part in decision-making processes, such as land-transfer agreements or the stipulation of working conditions. White and White (2012) also point out how the advent of palm oil companies has brought about changes in land ownership systems in rural areas in favour of male 'breadwinners', thereby limiting the access of women to land. These constraints also affect women's participation in sharing any benefits generated by oil palm development processes (Ibitoye et al 2011, Bassey 2016, Elmhirst et al 2017a); women generally respond to such obstacles by using alternative strategies that demonstrate their resilience and adaptability to changing circumstances (de Vos and Delabre 2018).

The above-described conditions are confirmed in a study (DTE 2014) conducted in a production area in Papua (Indonesia) that listed various conditions of hardship for women, such as job instability, loss of access to farming land and forest resources, and high food prices. In contrast, another study in Bungo (Indonesia) analysed gender-disaggregated data regarding participation in land-use decision-making and found that the conversion of agroforestry areas into plantations for cash crops, such as rubber and oil palm, was essentially a decision made by men and women together for the purpose of increasing their mutual access to capital (Feintrenie et al 2010, Therville et al 2011).

Other studies, mainly in Africa and South America, maintain that the production of oil palms has had positive effects on gender equality. A study (Adebo et al 2015) conducted in a small province in Nigeria shows that the women involved in the production of palm oil tend to share a number of recurring socio-economic characteristics: they are mainly married, relatively young, have a low literacy level and, first and foremost, they all work on small farms of less than 2 ha in size. The study shows an improvement in the income and standard of living of women involved in the production of palm oil, concluding that efforts to promoting the employment of women in this sector would bring about a reduction in poverty rates among women and their families, especially in rural areas. The same study records positive impacts in terms of gender equality along the entire palm oil production chain, from planting to processing and marketing, as well as among the different types of players involved in the chain such as growers/producers, processors, dealers and consumers; generally speaking, women tend to be more frequently employed in the processing phase of the palm fruit and in marketing activities for the companies, suggesting a diversified level of gender involvement along the production chain (Omonona and Agboje 2013, Adesiji et al 2016, Elmhirst et al 2017a, 2017b). Another study in Ghana (Etuah et al 2020) concludes that involvement in the oil palm activities contributes positively to women's empowerment, but many inequalities in the supply chain still exist between men and women.

A number of initiatives in Guatemala are promoting cross-cutting policies to prevent gender discrimination, fostering the setting up of gender committees to operate as a mechanism for dialogue, protection and support of female workers, for the purpose of safeguarding their rights and advancing their interests within the large companies in the palm oil supply chain (Grepalma 2020).

Gender aspects are taken into account in the production of sustainable palm oil. In particular, multi-stakeholder initiatives (such as RSPO) have been upping their efforts in recent years to safeguard the rights of female workers in the oil palm economy (Elmhirst et al 2017a). A comparative study (McInnes 2017) of the most important existing standards for oil palm sustainability (RSPO, ISCC, ISPO, MSPO, SAN, HCS and RSB) revealed that all standards have criteria that prohibit discrimination, but the definitions of what constitutes discrimination vary widely from one standard to another. With regard to the protection of women, ISCC, RSB, ISPO and MSPO do not contain specific criteria (McInnes 2017), while RSPO and HCS promote a productive gender-sensitive approach, for example by including criteria and mechanisms to protect women from sexual harassment in the workplace (Yaap and Paoli 2014, McInnes 2017, Elmhirst et al 2017a) and by developing, in the case of RSPO, practical guidance on gender inclusion and compliance, approved in 2021 to integrate the 2018 RSPO principles and criteria and the 2019 ISH standard.

The expansion of oil palms has led to the conversion of forests in recent decades, with damaging effects on ecosystem services, loss of biodiversity and reduced water quality (Pacheco et al 2017, Elmhirst et al 2017a). Many studies report negative impacts in Southeast Asia (particularly, in Indonesia) where conventional oil palm cultivation is acknowledged to be the major cause of water pollution (Muyibi et al 2008). Large amounts of fertilizers are used in conventional oil palm cultivation in Indonesia (FAO 2005), and palm oil mill effluent (POME) is also a water-polluting discharge (Wu et al 2010, Moreno-Peñaranda et al 2015) with the power to degrade aquatic ecosystems (Comte et al 2015, de Jong et al 2015, Moreno-Peñaranda et al 2015). Soil erosion can also be caused by oil palm cultivation, especially when the palm canopies in the plantations have not yet reached full development (Lee et al 2012). In these cases, eroded soil can enter water bodies, further degrading the quality of the water (Cramb and Curry 2012, Obidzinski et al 2012).

The expansion of oil palm cultivation also risks competing with local agriculture by reducing the availability of arable land and water for the subsistence farming that is crucial to some indigenous peoples (Oosterveer 2014). One example of this is the expansion of oil palm plantations in the region of Tripa (Indonesia), which has led to water shortages for the rice fields (Tata et al 2010). Further studies conducted in various areas of Indonesia show an association between oil palm expansion and the negative impacts on water availability and quality, with direct consequences on the availability of drinking water for the local populations (Li 2015, 2018, Moreno-Peñaranda et al 2015); leading, in turn, to consequences for public health (Rist et al 2010, Dradjat 2012, Manik et al 2013, Moreno-Peñaranda et al 2015).

In this regard, a UNICEF report (UNICEF 2016) describes a negative impact on water quality caused by palm oil plantations in Indonesia as a result of the leaching of pesticides and agrochemicals, the discharge of POME and hydrocarbon contamination in rivers. This has led to reduced access by local communities to important sources of drinking water, with negative consequences on health, particularly that of children. The study underlines the need to undertake sustainable development in the palm oil sector with a view to achieving the 2030 SDGs. A study conducted in West Kalimantan (Indonesia) on the impacts of oil palm expansion showed lower water availability in a business-as-usual scenario compared to a sustainable intensification scenario, where the plantations had only been placed in areas suitable for expansion. Sustainable production provides more ecosystem services than the business-as-usual scenario without significantly affecting palm oil crop yields, but the quality of the habitat suffers degradation in both scenarios (Sharma et al 2019). Additionally, the implementation of integrated management practices in oil palm plantations, including the use of water harvesting and storage technologies and protection by means of riparian buffer zones (Luke et al 2019), is reported to be key to achieving sustainability in the oil palm industry (Nambiappan et al 2018, Foong et al 2019). The leading internationally recognized sustainable production standards (RSPO, ISCC, SAN and ISPO) include criteria for water rights and the shared use of water resources (Yaap and Paoli 2014). In particular, the RSPO certification standard lays down, in this sense, a number of principles aimed at reducing water pollution and specific criteria in order to identify and monitor objectives and targets to reduce impacts and improve water quality (Lord and Clay 2006, Furumo et al 2020, Lee et al 2020, Santika et al 2020).

SDG 8 is the most widely discussed in the studies analysed, with 59 papers out of 82 addressing these aspects. Considering the relevance and the complexity of the topics under this SDG, this section is structured by differentiating the impacts of palm oil on the two sub-items of this SDG.

3.7.1. Decent work

3.7.2. Economic growth

The existence of inequalities in the palm oil production sector may be due to different causes and groups of people. The main elements of inequality concern men vs. women, smallholders vs. large-scale producers and indigenous populations vs. large-scale producers. A study conducted in the province of Riau (Indonesia) also reports on the existence of economic inequalities between rural and urban areas (Syahza et al 2011). It maintains that in order to reduce these inequalities all the players in the oil palm supply chain should be involved, from local communities to economic operators and local governments, in order to convince the local populations of the potentially positive effects of the sustainable development of oil palm plantations, i.e. potential increases in income and consequent increases in purchasing power, effects with the power to improve the entire welfare system of rural areas.

According to Li (2018), sustainable development cannot be achieved unless everyone has the resources needed to achieve well-being; it cannot, therefore, be achieved without social equity. All too often the cost–benefit ratio connected with oil palm expansion differs on the basis of social class, community of origin, age and gender (Dayang Norwana et al 2011, Jelsma et al 2017, Elmhirst et al 2017a, Li 2018, Castellanos-Navarrete et al 2019), which is why there is an urgent need for an institutional framework to assist smallholders and improve the distribution of benefits in the sector (Elmhirst et al 2017a, Li 2018, Grepalma 2020, Qaim et al 2020). According to a study by Acosta and Curt (2019), investors and the Indonesian government share about 80% of the benefits generated by oil palm plantations, while only 14% of the benefits (infrastructure, employment, education and health) go to local populations. Another study shows that the expansion of oil palm cultivation in Indonesia has brought about improvements in the standard of living of smallholders in certain areas but that it has also generated economic and social costs (Santika et al 2019) due to increasing inequalities in the distribution of benefits which, in most cases, are only shared between rich farmers and skilled migrants, thereby giving rise to social inequalities and marginalization (Obidzinski et al 2012, Oosterveer 2014, Muhammad et al 2019).

Furthermore, large-scale producers have often expanded their plantations without carrying out the required prior consultations with the local populations (Sheil et al 2009, Feintrenie et al 2010, Rist et al 2010, Nkongho et al 2014), generating conflict with indigenous communities (Cramb and Curry 2012, Hoyle and Levang 2012, Oosterveer 2014, Abram et al 2017, Pacheco et al 2017). In Malaysia and Indonesia, the expansion of oil palm plantations into more remote areas has also led to indigenous peoples being displaced from their native lands (Alam et al 2015, Hidayat et al 2018). A World Bank report (Persey et al 2011) points out that conflicts between indigenous communities and companies have often arisen due to ambiguities in the rights governing the use of resources and land (Dradjat 2012, Mingorría et al 2014, Elmhirst et al 2017b, Hidayat et al 2018, Qaim et al 2020). Furthermore, Onoja et al (2017) underline the existence of a dangerous trend of land grabbing for oil palm expansion across Africa (Nkongho et al 2014, Bassey 2016). This is why sustainability certification schemes focus special attention on the need to involve local communities in decision-making processes. RSPO, for example, includes a mandatory requirement to obtain free prior informed consent from local communities before commencing any kind of project (Yaap and Paoli 2014). Another inequality is generated by the fact that farmers do not all have the same possibility to access capital and land, with those having availability of land and capital benefitting more from oil palm cultivation than those who are hampered by constraints and limitations in this sense (Krishna et al 2017, Dib et al 2018). Lack of access to capital can often oblige smallholders to sell their land (McCarthy 2010, Manik et al 2013, Dib et al 2018). Santika et al (2019, 2020) also demonstrate that the socio-economic impacts of oil palm expansion differ depending on the site-specific characteristics of the villages and, in particular, the basic socio-economic conditions of the villages prior to oil palm expansion. According to some studies, the adoption of practices for the sustainable production of palm oil brings about greater economic, environmental and social benefits than conventional production, benefits that are perceived by the farmers themselves (Elmhirst et al 2017a, Adiprasetyo et al 2019). Another study (Yaap and Paoli 2014) that analyses four certification standards—RSPO, ISCC, ISPO and SAN—shows that all four contain rules and principles aimed at preventing any form of discrimination related to race, gender, social class, sexual orientation, disability or political affiliation.