Health and Environmental Impacts of Pesticide Use in Agriculture

The occurrence of pesticide residues in food commodities has important implications for both human health and environmental integrity. Pesticides are designed to disrupt biological processes in target pests. However, many of these chemicals also affect non‑target organisms, including humans, wildlife, and beneficial ecosystems, especially when residues persist through the food chain or accumulate in the environment.

Human Health Impacts

Pesticide exposure affects human health through multiple pathways such as dietary intake of residues in food, dermal contact during application or handling, and inhalation of aerosols and dust during spraying. The health consequences of pesticide exposure are often classified as acute or chronic effects, depending on the duration, frequency, and level of exposure (Ejimerhomu et al, 2025; Kasperson et al, 2021).

Acute Health Effects

Acute pesticide poisoning occurs when individuals are exposed to high doses over a short period (Tambo et al, 2024). Symptoms can manifest rapidly and may range from mild to life‑threatening. Common acute effects include:

• Gastrointestinal distress, including nausea, vomiting, abdominal pain, and diarrhoea
• Neurological symptoms, such as headaches, dizziness, tremors, and convulsions
• Respiratory distress and irritation of the eyes and skin

In agricultural settings, acute poisoning is frequently reported among farmworkers and pesticide applicators due to inadequate use of personal protective equipment (PPE) and unsafe handling practices (Adebayo & Adeoye, 2023). However, acute effects may also arise in consumers following the ingestion of heavily contaminated food, particularly in areas where pre‑harvest intervals are not observed (Sulaiman & Abubakar, 2025).

Chronic Health Effects

Chronic exposure to pesticide residues through long‑term, low‑level dietary intake poses serious public health concerns, often more significant than acute effects because their consequences unfold over years or decades. Chronic exposures have been linked to:

1. Endocrine disruption, affecting hormonal balance, reproductive function, and metabolic processes.
2. Neurodevelopmental and cognitive disorders, particularly among children exposed in utero or early in life.
3. Carcinogenic effects, with associations reported for certain pesticide compounds and cancers of the prostate, breast, and lymphatic system.
4. Reproductive dysfunction, including reduced fertility, miscarriage, and birth defects.

The mechanisms of these health effects vary by chemical class. For example, organophosphate pesticides inhibit acetylcholinesterase (an enzyme crucial to nerve function), leading to neurological impairment, while certain pyrethroids and organochlorines have been implicated in endocrine‑related disruptions (Suleiman, Nuhu and Yashim, 2021; Sulaiman & Abubakar, 2025).

Empirical evidence from Nigeria suggests that dietary exposure among children may exceed acceptable daily intake (ADI) thresholds for certain pesticide residues, elevating concerns about long‑term health risks. Children are particularly vulnerable due to higher relative food intake per body weight and developing physiological systems that are more sensitive to toxic insults (Adebayo & Adeoye, 2023).

Environmental Impacts

The impacts of pesticide use extend beyond human health to encompass critical environmental processes, often leading to ecosystem degradation and biodiversity loss.

Soil Health and Microbial Diversity

Repeated application of pesticides can disrupt soil structure and function thereby reducing the diversity and activity of beneficial soil organisms such as earthworms, mycorrhizal fungi, and nitrogen‑fixing bacteria (Olatilewa et al, 2024). These organisms are essential for nutrient cycling, soil aeration, and plant health. Long‑term pesticide accumulation in soils can also diminish soil fertility, reduce agricultural productivity, and alter ecosystem balance (Onwudiegwu et al, 2025).

Water Contamination

Pesticides can leach into surface water and groundwater systems through runoff, spray drift, and erosion. Contaminated water bodies not only pose direct health risks to humans and livestock but also impact aquatic organisms. Fish and amphibians are particularly sensitive to chemical exposure, and pesticide contamination has been linked to reduced survival, reproductive failure, and disruption of food webs in freshwater ecosystems. These water contaminants may also end up in irrigation sources where they create cyclical exposure risks for crops and consumers (Siegrist & Zingg, 2021; Olatilewa et al, 2024).

Biodiversity Loss

Non‑target organisms, including pollinators (e.g., bees) and natural pest predators, can be adversely affected by pesticide exposure. Declining populations of pollinators have global implications for food security and ecosystem resilience. The loss of biodiversity reduces the capacity of ecosystems to adapt to environmental change and sustain agricultural productivity in the long term (Kasperson et al, 2021).

Further, environmental contamination by pesticide residues feeds back into agricultural systems in multiple ways. For example, degraded soils may require increased fertiliser inputs to maintain yields, thus, increasing production costs and potentially creating further environmental pressure. Similarly, reduced populations of natural pest predators may compel farmers to rely even more heavily on chemical controls thereby perpetuating a cycle of dependency and risk (Slovic, 2021).

Interconnections Between Health and Environment

There is a clear nexus between environmental contamination and human health. Water and soil contaminated by pesticide residues become secondary exposure pathways for humans through drinking water, irrigated crops, and animal products. These multiple exposure routes compound risks, particularly in rural communities that depend directly on local water sources and subsistence agriculture (Tambo et al, 2024).

The evidence discussed in this section indicates that pesticide residues are not only prevalent in Nigerian food commodities but also pose tangible risks to human health and environmental sustainability. These impacts underscore the need for stronger regulatory oversight, improved agricultural practices, and targeted public health interventions. They further justify the present study’s focus on how public perception aligns (or misaligns) with scientifically assessed health and environmental risks, and how this shapes consumer behaviour in the Nigerian context.