Biomagnification, the progressive increase in toxin concentration along the food chain, poses significant threats to ecosystems and human health. This chapter delves into the behavior of pesticides in the environment, their impact on organisms, and the ensuing human health ramifications. Pesticides, crucial for bolstering agricultural productivity, infiltrate various environmental media, leading to contamination and adverse effects. Surface and groundwater sources become reservoirs for pesticide accumulation, affecting aquatic organisms and ultimately humans through the food chain. Biomagnification exacerbates pesticide concentration in higher trophic levels, accentuating health risks for predators, including humans. The intricate interplay of pesticides with environmental organisms illustrates varied toxicity responses, influencing species dynamics and ecological equilibrium. Human exposure to pesticides, predominantly through agricultural activities, presents acute and chronic health risks, ranging from respiratory issues to carcinogenesis and endocrine disruption. Mechanisms underlying pesticide-induced health effects, such as neurotoxicity and carcinogenicity, underscore the need for stringent regulations and sustainable agricultural practices. The chapter advocates for continued research, monitoring, and education to mitigate pesticide-related environmental and health hazards, promoting safer food production and ecosystem conservation.