Developing countries are commonly characterized by large agricultural populations and poor rural communities (1). Agricultural activities continue to play a significant role in ensuring sustainable food supply, which can be afforded even by the poorest in the country against the background of escalating population growth and changing dietary patterns. In a report by the Food and Agricultural Organization (FAO) (2), there is an increasing trend of agricultural area presented in terms of percentages over the years for Southeast Asian countries, except for Malaysia, Singapore and Brunei. The increment of land use between 2005 and 2011 is as follows; Cambodia, 30.3%–32.0%; Indonesia, 27.2%–30.1%; Laos, 8.7%–10.3%; Myanmar, 17.2%–19.2%; Philippines, 38.0%–40.6%; Thailand, 38.4%–41.2 and Vietnam, 32.4%–35.0%.
Data from the European Environment Agency showed that average pesticide consumption is usually parallel to per unit area of agricultural land (3). This means that although no similar data in documented report on pesticide usage are available for Southeast Asia, it is estimated that pesticide production and use have increased continuously year by year in line with the increasing agricultural area and the need to provide high-yielding food and crop productions to meet economic and population demands. The continuous application and reliance on pesticide can pose serious implications not only for the environment but more importantly to human health (4), (5), (6). To enable comparison to be made, Table 1 presents the general agricultural characteristics of Southeast Asian countries.
According to the study by Palis et al. (9) and Kaewboonchoo et al. (10), 80% or 1.3 billion workers in Asia are active in agricultural sectors and production. With the extensive use of pesticide, there are concerns with regard to the health effects among those who are occupationally exposed in the agricultural setting. The World Health Organization (WHO) and the United Nations Environmental Programme has estimated that 1 to 5 million cases of pesticide poisoning occur among agricultural workers during the mixing and application of pesticides, whereas 20,000 fatalities worldwide have been reported due to working in pesticide-treated fields each year (9). In a separate report, WHO has estimated that 99% of the 300,000 fatalities due to pesticides poisoning take place in low- and middle-income countries (11).
FAO and WHO have been among the international organizations that have been much focused on protecting the safety and health of workers with regard to pesticide usage and exposure. FAO adopted the International Code of Conduct on Pesticide Management in 1985. In 2014, WHO adopted the same code of conduct as its reference framework for international guidance on pesticide management (12). Due to concern about health and environmental hazards, there are also several other international agreements that have come into force that is linked with pesticide usage and exposure. The most important of these are the Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade, the Stockholm Convention on Persistent Organic Pollutants (Stockholm Convention), the Basel Convention on the Transboundary Movement of Hazardous Wastes and their Disposal (Basel Convention), the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) and the International Labour Organization Convention No. 184 on Safety and Health in Agriculture (ILO Convention 184) (12).
The governing bodies in Southeast Asian countries have put significant effort to develop frameworks related to pesticide management within the context of occupational safety and health (OSH) to ultimately overcome the problem (4), (13), (14), (15), (16), (17), (18), (19). Unfortunately, most of these countries continue to have high mortalities due to pesticide exposures as reported in previous literature (9), (11), (20), (21). As such, there is a need to identify the gap in the implementation of the existing regulating framework or system of the pesticide management as well as in the safety and health practices at the agricultural sector. There are differences of pesticide-related legislations and OSH practices among Southeast Asian countries, but no review has been performed to systematically identify it. Thus, there is a need to review these comparisons to help point out the weaknesses of pesticide management framework in terms of its practice and implementation for better understanding.
This paper therefore aimed to provide a review on the existing regulations and OSH pesticide practice and management in Southeast Asian countries. As there are limited sources and studies that can be accessed because of the language barrier and limitation in information, this review was mainly aimed to provide a summary and concise conclusion of the reports and articles in English, which were based on the current policies and legal infrastructures directed towards the safety and health of workers in the agricultural sector.
This is a preliminary traditional literature review study that aims to identify the similarities, differences and weaknesses of the existing pesticide management system in Southeast Asian countries. Scopus, ScienceDirect, PubMed and Google search engines were assessed to obtain literature regarding pesticide management within the OSH context in agricultural sectors in Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam. Search strategies included variant terms for “pesticide act”, “pesticide use”, “agricultural pesticide”, “occupational safety and health” and “pesticide poisoning” as keywords for each Southeast Asia. The search date range was restricted between years 2000 and January 2016.
The inclusion criteria of the articles, reports, legislation documents and documents retrieval to be considered in the review were the following: (1) written in English, (2) open access journal/report and documents available on the website and (3) dealt mainly in pesticide legislation and OSH in agricultural sector. The search yielded a total 49 articles that met the inclusion criteria. The titles, keywords and abstracts of the articles were then screened for relevance, which left a total of 19 original and review articles suitable for preliminary review.
Because of the limitation of information on pesticide legislations and acts with regard to OSH in some of the countries, this review assessed alternative information made available through government websites and other relevant websites by international organizations. By this method, one book was obtained; three reports were gathered throughout this study which includes two reports from FAO of the United Nations and one report from the Pesticide Action Network Asia. Seven legislation documents containing information on pesticide management and OSH in agricultural sector were gathered from specific websites of government agencies and hazard guidelines from the WHO website. Other 14 documents retrieved (newspaper excerpts, statistics data) were also gathered for this study.
The alternative literature search strategy identified an additional book, reports, legislation documents and other documents retrieved, which were included in the study. The flow diagram of the literature search is as presented in Figure 1 .
To help present the summative outcome of the review at the country level, a cross-tabulation benchmark adapted from the United States Environmental Protection Agency (USEPA) (22) for safety and health in pesticide management was used. The benchmark variables composed of two elements, namely, (1) worker protection, which includes safety and health training to workers, protection [provide and maintain required personal protective equipment (PPE)] and decontamination (hygiene practice), and (2) safety practice in pesticide management which focused on pesticide registration, licensing, inspection, testing, container, trade, storage, disposal and prohibited pesticide use.
The current pesticide management authorities in each of the countries were headed by local government bodies related to agricultural practices. A brief statement of relevant local authority, primarily responsible authority in the current pesticide management and regulation framework, responsibility and reported use of pesticide in the countries of Southeast Asia is presented in Table 2.
All Southeast Asian countries are listed as a membership in FAO Code of Conduct for pesticide management. Indonesia and Philippines have ratified the Rotterdam Convention, whereas the rest are only accession of the convention except for Brunei and Myanmar. For Stockholm Convention, majority of Southeast Asian countries have been ratified except Brunei, Malaysia (signed) and Myanmar (accession) conventions. Whereas in the Basel Convention, only Indonesia and Malaysia have been ratified. The contents of these agreements promote an effort and initiate action to protect human health and environment due to the use of hazardous chemicals like pesticides in the member country. Details of the international agreement status by the Southeast Asian countries are presented in Table 3.
The countries with the highest usage of pesticide was Thailand, Philippines and Malaysia. From the results obtained, it was found that pesticide management was not given emphasis in Brunei and Singapore as the agricultural sector is not a dominant economy in these countries. Indonesia, Myanmar, Thailand and Vietnam have emphasized safety practice in the management of pesticide usage such as requiring pesticide registration, licensing, inspection, testing and others, but in terms of protection of workers, the focus is less compared with what is reported for Cambodia, Laos, Malaysia and Philippines.
Malaysia and Philippines have provided a framework on the training, protection and hygiene practice of workers to ensure they are secure from the risks of pesticide exposures in the agricultural settings. This is contrary to Laos and Cambodia, which provided training and protection practice for their workers but did not emphasize on hygiene practice for workers. For safety practice in pesticide management, which includes pesticide registration, licensing, inspection, testing, container, trade, storage, disposal and prohibited pesticide use, only Cambodia, Malaysia, Philippines and Thailand have fully complied with the benchmark adapted from the USEPA. The cross tabulation is presented in Table 4.
Table 5 represents the report of pesticide poisoning cases in Southeast Asian countries. From the data, farmers in each of the Southeast Asian countries have reported cases of pesticide poisoning except for Brunei, Laos and Singapore.
This study was able to identify and differentiate the framework of pesticide management in Southeast Asian countries, namely, Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam. From the results, pesticide management in these countries has been placed under the responsibility of respective governmental organization under the Ministry of Industry and Primary Resources (Brunei), Ministry of Agriculture Forestry and Fisheries (Cambodia), Ministry of Agricultural (Indonesia), Ministry of Agricultural and Forestry (Laos), Ministry of Agricultural and Agro-Based Industry, Ministry of Natural Resources and Environment, Ministry of Human Resources, Ministry of Health (Malaysia), Ministry of Agricultural and Irrigation (Myanmar), Fertilizer and Pesticide Authority (FPA; Philippines), Agri-Food and Veterinary Authority (Singapore), Ministry of Agriculture and Cooperative (Thailand) and Ministry of Agricultural and Rural Development (Vietnam).
By using a cross-tabulated benchmark adapted from the USEPA (22), it was found that there were differences that were apparent. The country with the least legal standards regarding pesticide is Brunei in which their management is more focused on the importation of plant materials and plant products such as living plants, fresh fruits, seeds, weeds and other organic fertilizers. According to FAO, only 5% of crops are locally produced in Singapore, and the rest of the food products are imported into the country (25). As such, Singapore almost completely depends on importation of fruits and vegetables into the country; therefore, the regulation on importation of food or crops is much more emphasized compared with the management of pesticide use.
Apart from Brunei and Singapore, Vietnam and Indonesia also have the least legal standards on pesticide management although both countries are the top three largest producer of rice (Vietnam) (38) and the major producer of palm oil (Indonesia) (39). The study by Phung and colleagues showed evidence that the legal standards on pesticide have not been developed and implemented in Vietnam because of several reasons, including lack of administrative and enforcement resources, insufficient knowledge on the part of regulators, limited environmental standards and poor cooperation, coordination and consistency in implementing regulation on the part of the relevant authority (17). On the other hand, the reason for lack of legal standards in Indonesia remains unclear due to the lack of published information.
For the element of worker protection, there were obvious gaps between the countries that applied the concept of OSH practice in the agricultural sector. From the results, Malaysia, Philippines, Cambodia and Laos have emphasized OSH practice during the handling of pesticide activities. In Malaysia, practical guidelines to ensure the safety and health of farmers and farm workers are issued under the Guidelines on Occupational Safety and Health in Agricultural Sector in 2002, which is under the authority of the Department of Occupational Safety and Health (DOSH) (19). The implementation of OSH practice in the agricultural setting in Malaysia thus should ideally have been well implemented; nevertheless, there are evidence of increased involuntary poisoning cases due to paraquat poisoning reported between the years of 2002 and 2008 (11). A ban on this pesticide was implemented in 2002; however, this ban was lifted in 2006, causing paraquat poisoning cases to be on the rise. It is clear from the evidence that there is a lack of oversight on the present regulating framework in the agricultural sector by the authority.
In the Philippines, the responsibility of regulating the pesticide management framework is placed under the FPA. The government organization has implemented periodic training among workers on proper and safe handling of pesticides, use of PPE, basic knowledge about chemical handling and first aid procedure in case of poisoning (15). The government has made requirements for the appointment of competent occupational health practitioners, which include physicians and nurses to conduct any treatment and health services for poisoning or other related health symptom regarding pesticide exposures among workers including farmers (15). Cambodia and Laos are focused on the protection of farmers through safety training and providing adequate and required PPE, but no emphasis on decontamination or hygiene practice is evident (15), (25), (26). In terms of the effectiveness of OSH implementation in the agricultural setting, there is no report on the monitoring of OSH practice and its performance in the field found in the literature for Cambodia and Laos. The measurement of OSH performance is crucial to identify lapses in its regulating framework.
By contrast, there is a lack of the worker protection element among farmers in the pesticide management framework in Myanmar and Vietnam and even in massive agricultural producing countries such as Thailand and Indonesia. In Thailand, the major crop grown is rice, and approximately 9.5 million tonnes of rice is exported in the year 2016 (40), whereas in Indonesia, approximately 26.9 million tonnes of palm oil was exported in 2012 (41). Therefore, these countries rely heavily on the use of pesticides like insecticides and herbicides to protect crops and increase yields (17). Thus, farmers are continuously exposed to various types of pesticides in their work, and these exposures will continue to increase because there is a lack of effort being implemented towards ensuring the protection of workers in these countries (18). A study in Thailand on knowledge, attitude and practice among farmers regarding the use of PPE found that the attitude towards PPE is poor, and although knowledge on the harm of pesticide is present, the farmers were not concerned about their overall pesticide exposures (16). Similar to a study in Indonesia at a pepper plantation, approximately 70% of the respondents did not use PPE and did not consider any protection against any contamination with pesticides (34). The study further reported that 77% of the respondents did not realize the possible effects of pesticide on their health (34). The lack of proper usage of pesticide practice among farmers may arise because they were not formally trained regarding the pesticide hazard; thus, any related symptoms from accidental pesticide exposures cannot be described to elicit accurate pesticide poisoning medical response (42). A study by Tawatsin and colleagues in 2015 reported that there are approximately 49,000–61,000 cases of pesticide intoxication in Thailand each year with the rate of morbidity between 76.4 and 96.6 per 100,000 populations (20). In Vietnam, it was reported that pesticide poisonings among farmers were due to the lack of PPE usage (37). Improper handling of pesticides has also been linked with pesticide poisoning in other countries such as Cambodia (33), Indonesia (11), (34), Myanmar (25) and Philippines (11), (35).
Across Southeast Asian countries, this review found that high amounts of pesticide usage were reported in Thailand, Philippines and Malaysia. Even with the existing framework on pesticide management, involuntary cases of pesticide poisoning have been reported to occur in these countries notwithstanding the fact that some have implemented strategies to ensure the protection of workers from exposures (11). It can be argued that this was due to the high demands for pesticides, which led to its increased manufacturing and imports into the countries (14), (16), (20), (25), (26), (30) and has created a massive challenge in the enforcement of pesticide management. Most of the countries such as Cambodia, Malaysia, Thailand, Vietnam and Philippines have banned and restricted extremely hazardous (class Ia) and highly hazardous (class Ib) pesticides such as acephate, dichlorodiphenyltrichloroethane, endosulfan, methamidophos, monocrotophos, methyl parathion and paraquat (13), (16), (25), (26), (42) from use in the agricultural sector. However, numerous reports have shown that some of the prohibited pesticides were continuously being used throughout the country. These reports have been documented in several studies (11), (14), (16), (26), (33), (43), (44). These evidences prove that some of the international agreements signed and ratified were not fully complied with.
In Thailand, the study by Panuwet and colleagues reported that government in general has recognized this problem and has made efforts to enforce and improve existing regulations, but the capacity of the governing bodies in its enforcement has not expanded in line with the increasing pesticide use, and it is a struggle to create a solution in managing pesticide when the number of staff available is much fewer than the number that is actually needed. Therefore, the issue of illegal or non-registered pesticides imported into the countries continues to persist (16). For Philippines, Indonesia, Laos and Myanmar, there is no specific study that highlighted the issue regarding the use of non-registered or illegal pesticide in their country.
From this review, it can be summarized that OSH practice among local farmers is not yet a central point in many of the Southeast Asian countries. Education and technical support towards safety and health among local farmers need to be taken into account in all of these countries to instill a good agricultural practice that relates to pesticide handling in the workplace in order to improve the awareness of the workers. In addition, governing bodies should increase the enforcement, its oversight and the number of staff who are responsible in restricting the use of highly hazardous pesticides as a way to decrease pesticide exposures among farmers.
This review had some limitations that need to be considered. There were minimal data and reports that are available online for pesticide management. The scope of this review is made smaller with the language restriction where only studies provided in English were included in the results. There is the slight possibility this review had missed some key facts in its discussion due to the language barrier. When available, the reports from different Southeast Asian countries were not within a common format to enable comparisons to be made. Most of the data were obtained from published reports by the FAO of the United Nations, which has assisted countries in Asia and the Pacific for the past 30 years with regard to pesticide legislation and regulations.
From this paper, the similarities, differences and weaknesses across countries regarding the management of pesticide usage in terms of OSH in agricultural sectors in Southeast Asia have been briefly summarized. In terms of legislations, all of the Southeast Asian countries have assigned local authorities and government organizations to manage and control pesticide use in their agricultural sector. However, there is a massive challenge for pesticide management in most Southeast Asian countries because cases of pesticide poisonings continue to occur and banned and restricted pesticides are still being made available in local markets as well as being illegally imported. The implementation of OSH regulation among the farmers need to be improved by the diagnosis, health surveillance and reporting system as well as following or adopting the standard guidelines for the protection of workers in terms of safety and health in the agricultural sector. Furthermore, research on the monitoring of safety and health performance also plays an important role in OSH development in Southeast Asian countries and needs to be continually emphasized.
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About the article
Published Online: 2017-10-21
Research funding: This review paper was made possible because of the financial support from the Ministry of Higher Education Malaysia (MyBrain15 Scheme) and the Universiti Putra Malaysia (Inisiatif Putra Siswazah) under Vote 9466400. Conflict of interest: None of the authors had any conflicts of interest, and there was no corporate sponsorship of this research. Informed consent: Informed consent is not applicable. Ethical approval: The conducted research is not related to either human or animal use.