Biological Hazards in Agricultural Work: A Scoping Review of Occupational and Environmental Health Challenges

Agricultural workers in Malaysia are consistently exposed to biological hazards originating from soil, water sources, livestock, and vector populations. Environmental conditions, such as tropical climate, monsoon-related flooding, and deforestation, further exacerbate the risk of zoonotic and vector-borne diseases. Despite these risks, biological hazards remain less extensively studied compared to physical and chemical exposures. This scoping review aimed to synthesize the current evidence on biological hazards affecting Malaysian agricultural workers, with an emphasis on occupational and environmental determinants, surveillance gaps, and preventive challenges.

A scoping review was conducted following Arksey and O’Malley’s methodological framework and the PRISMA-ScR guidelines. Peer-reviewed studies published between 2016 and September 2025 were retrieved from major databases. The eligible studies included biological hazards associated with paddy farming, plantation work, livestock production, and aquaculture. Data were charted according to hazard type, agricultural setting, study methodology, and the identified determinants.

A total of 47 studies met the inclusion criteria. The findings identified a diverse range of pathogens linked to occupational exposure, with Leptospira spp. being the most frequently reported, followed by Plasmodium knowlesi, Burkholderia pseudomallei, and various tick-borne agents. Environmental determinants, including contaminated soil and water, inadequate sanitation, climate variability, and high vector density, were consistently associated with increased disease occurrence. However, surveillance systems remain fragmented, with limited longitudinal monitoring and inconsistent reporting of biological hazards.

This review highlights substantial knowledge gaps in understanding emerging biological hazards, climate–disease interactions, and the effectiveness of existing preventive strategies. Weak integration of occupational health, environmental monitoring, and vector surveillance limits timely detection and response. These gaps reduce the accuracy of disease burden estimates and hinder the development of targeted risk-reduction measures.

Biological hazards in Malaysian agriculture constitute a critical yet under-monitored occupational health threat, influenced by environmental and climatic dynamics. Strengthening One Health-based surveillance systems, updating national policies, and integrating environmental microbiology into occupational health programs are essential to address these gaps. Enhanced monitoring, adaptive prevention strategies, and cross-sector collaboration are necessary to safeguard worker safety and ecosystem health in changing climates.