Assessing Pesticide Exposure and Regulatory Challenges in Malaysia: A Review of Population Monitoring, Food Residue, and Environmental Contamination

Abstract

Pesticide applications do not always stay confined to their target. Human exposure to pesticides can lead to various health effects, such as cancer, reproductive toxicity, and neurodegenerative disorders. For that reason, stringent regulations govern pesticide registration and application before they enter the market. This objective of this article is to review studies conducted in Malaysia related to human biomonitoring and pesticide residue monitoring in the environment and food with the aim to explore the extent and pathway of pesticide exposure among the population, which indirectly allows us to examine the effectiveness of pesticide regulatory systems. Articles published from 2010 until 2024 from ScienceDirect, Scopus, and Google Scholar were explored. In Malaysia, biomonitoring of pesticide is conducted sporadically by independent researchers and does not provide a comprehensive understanding of the population's exposure through various routes of exposures. Additionally, the effectiveness of environmental regulatory measures remains unclear because of lack of monitoring data available publicly for interpretation. Moreover, dietary exposure assessments of pesticide residues in food are conducted randomly in Malaysia. This approach contrasts with other countries where the Total Diet Studies comprehensively evaluate the entire population's exposure to pesticide residues through dietary pathways. In summary, there is a need for a more comprehensive and systematic study of Malaysia's pesticide regulatory system specifically through biological, environmental, and food monitoring. Understanding the effectiveness of current regulations in controlling pesticide exposure is vital not only for public health but also for overall environmental well-being of the nation.

Keywords

pesticide exposure - pesticide regulations - biomonitoring - residues - pesticide exposure

Introduction

Pesticide usage in Malaysia, driven primarily by agricultural activities and domestic application for weed and pest control, poses significant concern for human health and the environment. This problem stems from the nonselective nature of pesticide application, leading exposure through various routes: occupational (workplace exposure[1]), indoor (home application[2]), dietary (from foods and drinks[3]), and environmental routes (presence in water[4]; [Fig. 1]).

Fig. 1 Multiple sources of pesticides to human.

In Malaysia, the agricultural sector contributed 6.6% to Malaysia's gross domestic products (2022),[5] and its impact on human health and environment should not be overlooked. As an example, a recent publication has highlighted one of the severe health effects associated with pesticide exposure, Mesoamerican nephropathy kidney failure in agricultural migrant workers.[6] Malaysia regulates pesticide registration through the Pesticide Act 1974,[7] granting authority to the Pesticide Board for oversight to address these concerns. Pesticide must undergo a rigorous registration process, involving the preparation of comprehensive dossiers encompassing toxicology, ecotoxicology, efficacy, and residue data.

This article critically examines Malaysia's pesticide regulatory system to assess its effectiveness in mitigating pesticide exposure. We conducted a comprehensive review of studies examining pesticide residue levels in food, the environment, and biological samples of the Malaysian population. Our goal is to identify gaps and limitations in the current regulatory system and propose evidence-based solutions to protect public health and the environment.

We analyzed studies on:

• Biological monitoring: to assess internal pesticide exposure in the population.

• Food residue: to evaluate dietary exposure through contaminated food.

• Environmental contamination: to examine pesticide levels in various environmental media.

By examining these three key areas, we aim to develop recommendations for improving Malaysia's pesticide regulatory framework and ensuring a safer and healthier environment for all.

Methods

Search Strategy

This is a nonsystematic, narrative review pertaining to pesticide analysis in food, environmental, and biological matrices in Malaysia ([Table 1]). The objective is to evaluate the effectiveness of Malaysia's pesticide regulatory system in protecting the public health and environment. Articles in English from various studies in Malaysia were collected via literature search engines such as ScienceDirect, Scopus, and Google Scholar. The search was conducted up until the year 2024 for all types of research design.

Table 1 The keywords and articles retrieved for each section of this review

Search term	Articles retrieved	Remark
“Pesticide,” “Health,” and “Malaysia”	16 articles	Conducted from 2010 until 2024.
“Pesticide,” “Food,” “residue”	8 articles	Conducted from 2010 until 2024. Most publications presented method development results. This review only includes publications that include analysis of real sample.
“Pesticide,” “Environment”	8 articles	Conducted from 2018 to date because of the presence of other review papers

Result and Discussion

Biological Monitoring (Biomonitoring) of Pesticides in General Population

Biological monitoring measures and evaluates specific biological indicators or markers in an individual's body fluids, tissues, or exhaled breath to determine exposure to hazardous substances or evaluate the health effects of such exposures. It is utilized frequently in occupational and environmental health to monitor individuals who may have been exposed to toxic chemicals or other harmful agents.[8] Based on the pathway for biological monitoring, there are three primary types of biomarkers, which are biomarkers of exposure, biomarkers of effect, and biomarker of susceptibility ([Fig. 2]).[9] Biomarkers of exposure refer to the absorbed dose of the hazardous substance in the worker, while biomarkers of effect represent the biological changes or responses to a substance's exposure. Biomarkers of susceptibility are genetic or biological factors that increase an individual's sensitivity to chemical exposure.

Fig. 2 Pathways for biological monitoring (adapted from Kapka-Skrzypczak et al[9]).

Biomonitoring is a pivotal instrument employed to assess and quantify the extent of environmental chemical exposure. Human biomonitoring (HBM) data play a crucial role in enhancing our comprehension of exposure patterns and furnishing valuable insights to manage health risks associated with various chemicals effectively. Numerous countries have implemented the National Biomonitoring Program with their respective national research institutes, such as in Korea,[10] European Union,[11] and the United States.[12] The primary objective of this program is to evaluate the extent of human exposure to environmental chemicals and to gain insights into the potential consequences of such exposure on public health. Biomonitoring activities encompass quantifying chemical substances or their metabolites within the human body, specifically by analyzing blood or urine samples. This analytical approach aids in assessing individuals' exposure to said chemicals.

The scope of biological monitoring for pesticide exposure in Malaysia is currently restricted to individuals within the working population who are directly exposed to pesticides as mandated by the Occupational Safety and Health (Use and Standard of Exposure of Chemicals Hazardous to Health) Regulations 2000.[13] The primary objective of this surveillance is to strengthen the prevention and control of occupational diseases and poisoning, ultimately leading to improved organizational productivity and the overall health of the working population.[14]

The extent of research conducted on the biological monitoring of pesticides in Malaysia is presented in [Table 2]. From the 16 articles, it is noteworthy to highlight that a subset of 4 papers specifically investigated children residing close to or within agricultural communities. It is important to emphasize that these studies did not encompass children from the general population. The remaining 12 papers examined the participation of individuals within the working people, specifically farmers, and sprayers. Notably, the study primarily focused on the male demographic.

Table 2 The summary of biological monitoring of pesticide exposure in Malaysia

Type of biological monitoring	Type of pesticides monitored	Study population	Source
BF (physiological test and blood biochemical changes)	CUP	WP (farmers, N = 152), CS	Hossain et al, 2010[19]
BX (urine metabolite)	OP	WP (farmers, N = 7)	TI et al, 2010[20]
BX (blood—chlorpyrifos)	CUP	WP (farmers, N = 100)	Hod et al, 2011[21]
BF (physiological health parameter)	2,4-D and paraquat	WP (farmers, N = 140)	Baharuddin et al, 2011[22]
BF (plasma AChE and genotoxic effect)	OP	WP (farmers, N = 32)	Vivien et al, 2013[23]
BF (physiological health parameter and blood biochemical)	CUP	WP (farmers, 39%)	Abdul Hamid et al, 2016[24]
BF (plasma AChE and genotoxic effect)	OP	GP (children from farming communities, N = 95)	How et al, 2014[25]
BF (plasma AChE and genotoxic effect)	OP	WP (paddy farmer, N = 160)	How et al, 2015[26]
BF (plasma AChE and neurobehavioral effect)	OP	GP (children from farming communities, N = 95)	Hashim and Baguma, 2015[27]
BF (blood biochemical and cardiovascular disease assessment)	OP and PYR	WP (mosquito control worker, N = 195)	Samsuddin et al, 2016[28]
BX (urine metabolite) BF (genotoxicity assessment)	OP	GP (indigenous children living near to agricultural farm, N = 180)	Sutris et al, 2016[29]
BF (plasma AChE and neurobehavioral effect)	OP	GP (children from farming communities, N = 683)	L et al, 2017[30]
BX (urine metabolites)	CUP	WP (farmers, N = 25)	Sidek Ahmad et al, 2021[31]
BF (neurobehavioral performance)	OP and PYR	WP (mosquito control worker, N = 158)	Yusof et al, 2022[32]
BX (blood serum—parent pesticide)	CUP—airborne	WP (paddy farmer, N = 85)	Rudzi et al, 2022[33]

Abbreviations: BF, biomarker of effect; BX, biomarker of exposure; CUP, current-use pesticide; GP, general population; OP, organophosphate; PYR, pyrethroid; WP, working population.

The pesticide poisoning database published by the Malaysia National Poison Centre[15] provides valuable insights into the incidence of pesticide poisoning from 2006 to 2015. The data reveal a notable gender disparity, with a ratio of 2:1 for men and women affected by pesticide poisoning. The same gender disparity has been observed in the agricultural sector, with men being more prevalent than women.[16] Consequently, this gender imbalance potentially leads to greater exposure of men to pesticides due to their increased involvement in agricultural activities.[17] However, it is vital to acknowledge the potential impact of physiological differences between men and women on pesticides' toxicokinetic and toxicodynamic mechanisms.[16] This has led to speculation that women may be more susceptible to pesticide exposure than men, thereby increasing the potential risks to their metabolic health. These considerations should not be overlooked as they have significant implications for public health.[18] In addition, while “biomarker of effect” has received considerable attention in numerous studies, “biomarker of exposure” and “biomarker of susceptibility” have not been given the same level of priority in most biological monitoring investigations about pesticide exposure in Malaysia.[19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33]

It is essential to note that most studies have primarily focused on pesticide exposure in workplaces or occupational settings. Consequently, our knowledge of how much the general population has been exposed to pesticides through environmental contamination (such as air, water, and soil), food residues, and household pesticide use remains limited. The scarce availability of comprehensive exposure data presents a notable obstacle in the execution of epidemiological investigations on pesticide exposure, particularly in low- and middle-income nations like Malaysia.

Taking the example from countries that have established the national HBM program, Malaysia shall consider taking the initiative to establish a HBM program that holds significant importance due to various reasons:

Exposure Assessment

Understanding the potential risks associated with environmental chemicals requires exposure assessment. HBM is a valuable tool for it allows direct measurement of pesticides or their metabolites in the human body.[8] By employing HBM techniques, researchers can gain insight into the actual concentrations of environmental chemicals in individuals, allowing for a more precise assessment of their exposure levels. This information is essential for thoroughly evaluating potential health effects and developing appropriate risk management strategies. The acquisition of this information is crucial for understanding the extent and trends of exposure and identifying plausible health risks.

Tracking Trends and Establishing Baseline

Implementing a national HBM program allows the systematic monitoring of exposure trends over time and helps establish a baseline reading and follow-up to identify changes in exposure levels. It would also monitor the efficacy of regulatory measures, analyze the consequences of environmental or health interventions, and evaluate the success of pollution control strategies from time to time.

Assessing Health Impacts

Using the HBM would facilitate identifying vulnerable populations more likely to be disproportionately exposed to environmental chemicals. Children, pregnant women, occupational workers, and people residing in areas with high contamination levels may be more susceptible to environmental health risks. Utilizing HBM data would enable the strategic allocation of resources and implementation of interventions to protect these groups and minimize their exposure risk.

Public Awareness and Education

National HBM programs would serve as valuable sources of evidence-based data for public education and awareness. The dissemination of data about chemical levels detected within the population enables individuals to make informed decisions regarding their lifestyle choices, consumption patterns, and implementation of measures to reduce their exposure. The technology allows individuals to proactively reduce their susceptibility to potential dangers, fostering a healthier living environment.

In general, implementing a national HBM program is regarded as a highly advantageous mechanism for comprehending the extent of human exposure to environmental chemicals, assessing associated health hazards, and providing crucial insights to guide policy-making processes. The phenomenon plays a pivotal role in safeguarding the well-being of the general populace, as it aids in preserving public health, the detection of nascent concerns, and the formulation of efficacious approaches to mitigate and forestall potential hazards.

Pesticide Residue Monitoring in Food

Pesticide usage in agriculture, intended to protect crops and boost food production, is a widespread practice. However, numerous studies suggest that the primary pathway of exposure for the general population is through their diet. A review of nonoccupational pathways for pesticide exposure in women living in agricultural areas found that dietary ingestion is a significant route.[34] This is supported by evidence of higher pesticide exposure in children of agricultural workers, which cannot be entirely explained by proximity, suggesting a “take-home” pathway.[35] Across the globe, pesticide residues have been detected in various types of food, including Malaysia.

As one of the control measures for dietary pathway, pesticide residues in food are regulated through maximum residue limits (MRLs), encompassing diverse fruits, vegetables, and other commodities. The establishment of MRLs ensures that the level of pesticide residue in food does not exceed the limits set by regulatory bodies for different pesticides and commodities. For Malaysia, the MRLs are published in Schedule 16 of Food Act 1983.[36]

In Malaysia, the control of pesticide residues falls under the Food Act 1983, overseen by the Ministry of Health.[37] At the same time, during pesticide registration, companies or manufacturers are obligated to provide pesticide residue data.[38] The data will help the authority to assess the potential risk of the residue in food, ensuring the food is safe for consumption.

In some nations, Total Diet Studies (TDSs) are conducted to monitor substances (including pesticides) in food mainly to estimate dietary exposures and associated public health risks. For instance, in 2019, the 25th Australian Total Diet Study reported that pesticide levels in Australian food are very low, with over 99% of them at undetected levels (below the limit of reporting).[39] However, in Malaysia, the status of TDS is unknown due to the lack of publications stating otherwise. Simultaneously, once pesticides are in the market, there is no publicly available data to confirm any frequent monitoring of pesticide residue in food by the authorities. This was clarified in the meeting report of the FAO (Food and Agriculture Organization) Pesticide Residue Monitoring Project for Association of Southeast Asian Nations (ASEAN) Countries: Situation Assessment meeting held on August 25, 2020.[40] The Malaysian representative stated that Malaysia's MRL monitoring was done randomly, where a target number of samples were collected from the markets. These results are not accessible to the public, meaning there is no information available to assess the level of pesticide residue in food in Malaysia independently. Consequently, the public cannot interpret whether their food consumption poses any health risks as it relies heavily on authorities' interpretations.

As previously mentioned, sporadic independent publications have investigated pesticide residue levels in specific areas in Malaysia, such as monitoring vegetables and fruits in Cameron Highland, Ipoh, Selangor, and Kuala Lumpur. Many of these studies involve analytical method development. [Table 3] lists all publications reporting pesticide residue analyses in Malaysian vegetables and fruits. Publications that develop analytical method without testing real samples are not included in the table. The residue found were below the MRL with some studies reporting higher than and at their MRL. Generally, these studies cannot represent the pesticide residue levels for Malaysia as a whole, let alone the dietary exposure of pesticides in our population.

Table 3 The reported pesticide residue studies in food for Malaysia

Pesticides	Sample/area of sampling (year)	Sample preparation	Analysis method	Findings	Ref.
OC	Rice grain and paddy plant parts from MARDI plots and farmers/Tanjung Karang (n.m.)	SPE	GC-ECD	Endosulfan sulfate in rice grain from farmers exceeded MRL (22.37 ppb) in Food Act 1983	Sabere et al, 2013[41]
CB, OC, OP, and PYR	Fruits and vegetables' sample/wet markets, Malaysia (n.m.)	SPME	GC-MS	All detected pesticides were far below EU and Codex MRLs	Abdulra'uf and Tan, 2015[a] [42]
OP, OC, CB, triazine, PYR, fungicides, and herbicides	Imported and domestic cocoa beans from smallholders and Malaysian ports/not applicable (years 2012 to 2013)	Liquid extraction and SPE clean-up	GC–MS/MS and LC–MS/MS	Chlorpyrifos detected in 9 cocoa samples, 2 exceeded MRL (149, 200 mg/kg)[b]	Zainudin et al, 2015[a] [43]
OC and OP	Green leafy vegetables/Cameron Highlands (n.m.)	SPE	GC-ECD	Vegetable pesticide residue 0–13.3% above MRL	Farina et al, 2017[a] [44]
OP, OC, CB, PYR, some fungicides, and other herbicides	Domestic cocoa beans from farmers and imported beans from ports (Indonesia, Cameroon, Nigeria, Venezuela, Ghana, Ecuador, Papua New Guinea)/not mentioned (n.m.)	d-SPE	GC-MS/MS	20% samples positive for pesticides >10 μg/kg. Endosulfan, deltamethrin, chlorpyrifos, cypermethrin, permethrin detected at MRL	Zainudin and Salleh, 2017[a] [45]
OC, OP, and PYR	Leafy vegetables from 7 different organic farms/Cameron Highlands (n.m.)	SPE (in Farina et al 2017)	GC-ECD	More than half of organic samples contained pesticide residues	Farina et al, 2018[46]
OP	Vegetables/Ipoh (n.m.)	SPME	GC-FPD	Chlorpyrifos detected in all positive samples (mostly mustard) below MRLs (1 mg/kg) under International Food Act, Food Act Regulation 1985, and Codex Alimentarius	Sapahin et al, 2019[a] [47]
OC, OP, and PYR	Vegetables/7 different areas of Cameron Highland during wet and dry seasons (n.m.)	SPE	GC-ECD	Most pesticides detected in vegetable samples, higher in the wet season. OPs detected more frequently than OC and PYR.	Munawar et al, 2021[48]

Abbreviations: CB, carbamate; d-SPE, dispersive solid phase extraction; GC-ECD, gas chromatography with electron capture detector; GC-FPD, gas chromatography with flame photometric detection; GC-MS, gas chromatography with mass spectroscopy; MARDI, Malaysian Agricultural Research and Development Institute; OC, organochlorine; OP, organophosphate; PYR, pyrethroid; SPE, solid-phase extraction; SPME, solid-phase micro-extraction.

^a (Ref): Publication on method development to analyze pesticide residue in food.

^b Malaysian Food Act 1983; n.m., not mentioned.

Environmental Monitoring of Pesticide

Pesticide's chemical, physical, and biological properties such as high lipophilicity, toxicity, water solubility, bioaccumulation, long half-life, and potential of long-range transport make them among the toxic compounds that pollute the environment, even after many years of application.[49] In Malaysia, the Environmental Quality Act 1974 is used to control the discharge of chemical and industrial wastes including pesticides into the environment, so that there will be no adverse effects on human health and the environment.[50] However, it is not clear the effectiveness of the Environmental Quality Act 1974 in controlling pesticide contamination in the environmental matrices in Malaysia.

A review article on pesticide contaminations and analytical methods of determination in environmental matrices in Malaysia and their potential human health effects was published in 2018.[51] The latest review on the chronic effects of organic pesticides on the aquatic environment and human health was reported in 2022.[52] The review provided a comprehensive overview of the levels and distribution of organic pesticides in environmental compartments of the Asian region and the chronic effects of pesticides on human health. In their report, the authors highlighted the importance of more specific research to be conducted and comprehensive data should be maintained to prevent the adverse effects of pesticides on human health and the aquatic environment. However, this article is only limited to the aquatic ecosystem, and does not include other environmental compartments such as the terrestrial, wetland area, urban sites, and air. This section will provide information on the analytical methodologies for monitoring pesticides conducted in the environmental samples. In addition, information on the impact on human health and the environment will be reviewed based on the previously reported studies.

In reviewing the existing literature, most of the reported studies[53] [54] [55] [56] [57] focused on the development of analytical methods for the monitoring of pesticides in many kinds of environmental matrices in Malaysia. Several types of pesticides were analyzed and involved in the monitoring process, namely organochlorines, organophosphates, neonicotinoids, strobin, thiadiazin, anthranilic diamide, azole, pyrazole, dithiolane, triazine, chloroacetanilide, and imidazolinone herbicide. Depending on the types of samples, the sample preparation methods that were commonly used include Soxhlet extraction and solid-phase extraction. However, analytical methods that were commonly performed were liquid chromatography and gas chromatography based on the volatility of the pesticides used in the study. The environmental samples used for the analysis of pesticides in Malaysia include soil, sediment, various types of water samples, and indoor dust samples. There were not much data on pesticide effects on human health available from 2018 to the present. Very few studies conducted the hazard quotient value[58] [59] and risk assessment[60] of the analyzed pesticides.

[Table 4] summarizes the reported concentration of pesticides, the sample preparation techniques, analytical instrumentation, the area and year of sampling, the environmental matrix, and the potential health effects that they imposed on humans and the environment in Malaysia from 2018 until the present.

Table 4 Studies reported pesticide level in environmental samples in Malaysia from 2018 until present

Pesticides	Environmental sample	Sample preparation	Analysis method	Concentration found	Area of sampling (year)	Impact to human health and environment	Ref.
OC	Soil of lowland paddy field	Soxhlet extraction and clean-up using Florisil	GC-ECD	<LOD–7.34 µg/kg • LOD: limit of detection, LOD α HCH (0.02), β HCH (0.02), γ HCH (0.02), δ HCH (0.03), endosulfan sulfate (0.01) express in mg/kg	Machang, Kelantan, Malaysia (September 2017 and February 2018)	Hazard quotient values below 1, all samples unlikely to pose health risks.	Osman and Khalik, 2018[58]
Fungicides, neonicotinoids, pyrazoles, dithiolanes, chloroacetanilides, anthranilic diamides, and others.	Paddy soil and water using	Modified QuECHERS and dispersive solid-phase extraction	UHPLC-MS/MS	Paddy water samples: <MQL–11.83 ng/mL Paddy soil samples: <MQL–34.81 ng/g • MQL: method quantification limit, 0.08–1 ng/g in soil and 0.5–25 ng/L in water	Puchong, Selangor, Malaysia (n.m.)	Not mentioned.	Zaidon et al, 2019[53]
Imidazolinone and herbicides	Clearfield rice soil	Solvent extraction and solid-phase extraction	HPLC-UV	Imazapic: 0.03–0.58 µg/mL Imazapyr: 0.03–1.96 µg/mL	Sawah Sempadan-Tanjung Karang, Selangor, Malaysia (November 2016)	Not mentioned. However, imidazolinone herbicides persistent in soil, residues up to 85 days.	Bzour et al, 2019[54]
OPs	Mariculture sediment	Soxhlet extraction along with solid-phase extraction	LC-MS/MS	<MDL • Method detection limit (0.006–0.093 ng/g)	Pulau Kukup, Johor, Malaysia (n.m.)	Low concentrations of targeted compounds may pose long-term environmental and human health risks.	Ismail et al, 2020[55]
OCs	Tap water, river water, and palm oil mill effluent	Magnetic solid-phase extraction using newly developed adsorbent (magnetic oil palm fiber activated carbon-reinforced polypyrrole)	GC- μECD	Not detected	N.m.	Not mentioned	Marsin et al, 2002[56]
OPs	Tap water, river water, lake water, and wastewater	Magnetic solid-phase extraction using a newly developed adsorbent (magnetic-carboxymethyl cellulose nanofiber (Fe3O4-cmCNF) composite from oil palm empty fruit bunch)	GC- μECD	0.27–1.31 ng/mL	UiTM Cawangan Negeri Sembilan, Kuala Pilah, Negeri Sembilan, Malaysia (November 2021)	All positive OPP samples below EU regulations (0.5 ng/mL) except diazinon and malathion in wastewater.	Mohamed et al, 2022[57]
Pesticides removal of some fungicides, neonicotinoids, pyrazoles, dithiolanes, chloroacetanilides, anthranilic diamides, and others.	Water samples collected from drinking water treatment plant	Solid-phase extraction	UHPLC-MS/MS	Highest concentration: propiconazole (4,493.1 ng/L) Lowest concentration: pymetrozine (1.3 ng/L)	Tengi River Basin, Tanjung Karang, Selangor, Malaysia (n.m.)	HQs and HI for all target pesticides <1, no significant chronic noncarcinogenic health risk from drinking water consumption.	Elfikrie et al, 2020[59]
210 pesticides	Indoor dust	Solvent extraction and sonication	LC-Q-TOF	2,340–50,000 ng/g (8 insecticides, 8 fungicides, and 3 herbicides)	Kuala Lumpur, Malaysia (April–May 2020)	Toddlers had highest cancer risk among all age groups.	Yang et al, 2022[60]

Abbreviations: GC-μECD, gas chromatography with microelectron capture detection; GC-ECD, gas chromatography with electron capture detector; LC-MS/MS, liquid chromatography with tandem mass spectrometry; LC-Q-TOF, liquid chromatography quadrupole time-of-flight mass spectrometry; UHPLC-MS/MS, ultra-high performance liquid chromatography coupled with tandem mass spectrometry.

Pesticide Regulatory Challenges in Malaysia

The issues highlighted in the previous sections underscore the critical role of a robust regulatory system in mitigating pesticide exposure. However, Malaysia faces several challenges in this regard. As an example, at the time of writing of this article, chlorpyrifos was still sold on the biggest e-commerce platform in Malaysia, Shopee.[61] Chlorpyrifos was banned in the agriculture sector in Malaysia from May 1, 2023. This raises questions on the enforcement of the existing pesticide regulatory system in Malaysia. The challenges faced include but not limited to:

• Fragmented regulatory landscape: Malaysia faces a challenge in regulating pesticides due to a fragmented regulatory system. Different laws govern various aspects of chemical management, creating complexity and potential loopholes. This fragmentation can make it difficult to effectively oversee the entire lifecycle of pesticides, from production and registration to use and disposal. As an example, the Department of Agriculture might regulate pesticide registration and use while the Department of Environment might handle disposal and environmental impact of chemicals. At the same time, the Ministry of Health might be responsible for the health risks associated with specific chemicals. This division of responsibility can lead to complexities and potential gaps. For instance, a loophole in pesticide regulations might not be caught because different agencies oversee different aspects.

• The e-commerce dilemma: the presence of illegal pesticides on online platforms like Shopee raises concerns about public awareness and enforcement. While platforms like eBay have strict sanctions against such sales, the situation in Malaysia suggests a gap. This raises questions whether the public are adequately informed about the banned pesticides. Additionally, it is not also clear whether there were clear amnesty periods for farmers to dispose of banned chemicals before the sales became illegal.

• Cradle-to-grave disconnect: an effective pesticide regulatory system adheres to a cradle-to-grave approach. This means tracking a pesticide throughout its lifecycle, from manufacturing and import to use and disposal. However, current tracking systems in Malaysia may not fully meet this requirement. This lack of comprehensive tracking makes it difficult to ensure the safe use and disposal of pesticides, potentially posing a risk to public health and the environment.

Conclusion

The current regulatory landscape in Malaysia is insufficient to protect public health and the environment from the adverse effects of pesticide use. We have presented evidence highlighting the pressing need for a comprehensive and systematic approach to understanding pesticide exposure in our population. Currently, Malaysia has limited biomonitoring initiatives, sporadic pesticide residue assessments in food, and insufficient evidence of comprehensive environmental monitoring. The gaps in the current system pose substantial risks to public health and environmental well-being.

By taking decisive action to strengthen our regulatory framework and implement effective monitoring programs, we can significantly reduce the risks associated with pesticide exposure and ensure a healthier and more sustainable future for Malaysia. We proposed an integrated strategy to address these challenges ([Fig. 3]). First, the establishment of National HBM Program is vital. This program will inform our nation the extent and the trend of pesticide exposure (and other chemicals and pollutants) but also as a foundational tool for evaluating the effectiveness of the regulatory measures and allowing the development of the appropriate evidence-based policies. Second, there is also a need to transform the overall approach to pesticide residue monitoring in Malaysia. Adapting a transparent, regular, and rigorous monitoring program like TDSs conducted in other nations can provide accurate insights into dietary exposure and ensure food safety. Finally, assessing the effectiveness in the current environmental protection regulation is crucial to safeguard our environment and public health.

Fig. 3 Proposal of national integrated strategy in addressing pesticide exposure in Malaysia.

To sum it up, our review has not only identified the challenges but also offers a roadmap for future action. The existing gaps identified can be filled through collaboration of regulatory bodies, researchers, and policymakers. Besides, the collaboration may also assist in establishing a robust framework that protects the public health and well-being. Failure to act not only jeopardizes public health but also undermine the efforts toward environmental sustainability.

Conflict of Interest

None declared.

Acknowledgment

The authors would like to thank the Department of Toxicology, Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia.

Compliance with Ethical Principles

No ethical approval is required for review-type article.

Authors' Contributions

All authors contributed to collecting the data, writing the article, reviewing, and approving the final article.

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Publication History

Article published online:
27 December 2024