General cropping context

Asia is the main rice-growing region of the world, accounting for about 90% of global rice production, which is estimated at around 757 million tons of paddy rice annually (FAOSTAT, 2020). Therefore, this region of the world is of essential importance for both local and global food security. Cambodia is a major rice producer, including for export, and representative of the rice growing situation encountered in many countries of South-East Asia.

In Cambodia, rice is the staple food, with records of 68 to 70% of daily calorie intake. Paddy rice production has increased rapidly in the last decade, due to an expansion of the harvested area and improvements in yield. For instance, Cambodia produced 9.3 million tons of paddy rice in 2015, up from 4.0 million tons in 2000. This improvement was due to an expansion in cultivated land area (from 2.3 to 3.0 million ha) and to improved yields (from 2.1 to 3.1 tons ha-1) (MAFF, 2016). The increase in Cambodia's rice yield is due to several factors, including an expansion of irrigation infrastructure, wide use of high-yielding varieties, and an intensification of the crop cycle through double-cropping during the main wet season, as well as the accelerated application of agricultural inputs (i.e., fertilizers, pesticides).

Besides increasing rice production, which has been the leitmotiv since the green revolution, the population has recently been educated in the concerns of food quality. Nowadays, consumers consider food security and food safety. Over the last decade, policymakers in developed countries have applied food quality controls to reduce the amount of carcinogens or environmentally harmful molecules present in imported plant products, including cereals.

Pesticide use & regulation in Cambodia

Currently, neonicotinoid insecticides are very popular for use against insect parasites due to their low toxicity to mammals compared with previously used organophosphates and carbamates. In Cambodia, farmers commonly use insecticides belonging to the neonicotinoid family (Matsukawa et al., 2016). These insecticides are not yet included in the country’s updated list of banned or restricted pesticides (MAFF 2019).

Indiscriminate use of pesticides not only puts sustainable agricultural production at risk through the disturbance of vital ecosystem services, but pesticide residues on fresh products that exceed the maximum (allowable) residue limits (MRLs) also raise food safety concerns and threaten export potential. MRLs are standards set by individual countries for traded agricultural commodities according to types of pesticides. Pesticide residues result from: i) heavy pesticide use on the growing crop; ii) insecticide used in post-harvest management to preserve food during storage; and iii) the persistence and carry-over effect of residues in the soil. Survey studies of pesticide contamination of vegetables in Cambodian markets found products containing residues of organochlorine, organophosphate and carbamate (Wang et al. 2011) exceeding MRLs. Cambodia ranks first among 13 countries in the region with the highest pesticide residues on vegetables. This is the result of the indiscriminate use of pesticides by farmers, as well as a lack of understanding about pre-harvesting intervals. A study by the Cambodian Center for Study and Development in Agriculture (CEDAC 2003) found that farmers along the Mekong River commonly used high dosages of extremely hazardous chemical pesticides on vegetables and rice. Due to a limited advisory structure, many Cambodian farmers take recommendations from pesticide vendors: the consequence is the overuse of pesticides and their presence in end-products (Matsukawa et al., 2016).

The weak enforcement of pesticide regulations in Cambodia does not help farmers who have another use rationality, more adapted to their everyday constraints (Bureau-Point, 2021). In 1994, there were only 30 pesticides on the market; this increased to 241 in 2000, of which 42 were prohibited in Vietnam and another 16 were banned in Thailand. The increase reached 757 in 2009 (CEDAC 2010). Clearly, Cambodia has become a dumping ground for unwanted and dangerous pesticides (EJF 2002).

The EU is the biggest market for Cambodia’s rice. In 2016, the EU imported 341,066 tons of Cambodian milled rice. The EU commission originally announced that Cambodia’s milled rice industry must eradicate the use of several pesticides (such as Tricyclazole, a common fungicide used against blast disease and banned in Europe, as well as several nematicides) by June 2018 and that exports of Cambodian rice must not contain more than 0.01 mg of the chemical per kg, or face bans. This new regulation is advancing the switch-over of Cambodian rice agriculture towards the production of higher rice quality.

Pesticide reduction in rice

Different projects have started to measure the real use of pesticides in rice crops in Cambodia. During a recent survey in five provinces with 80 farmers interviewed, Flor et al (2019a and b) found that field level practices, up to stakeholder interactions, prompted farmers to adopt a “pesticide lock-in". Nevertheless, different value chains co-exist for rice in Cambodia and certain projects promote organic and sustainable rice (through the Sustainable Rice Platform, SRP). A project on anthropology (2018-2020) highlighted how pesticides became a cause of health concern for the general population. Other research projects are starting in the intensified context of Kandal province to better understand the use of pesticides and its links with water management, water pollution and human health.