Biomagnification significantly impacts ecological processes and human health. Some algal blooms due to eutrophication pose even more serious threat due to production of noxious toxins, such as microcystin and anatoxin-a, which are referred to as harmful algal blooms (HABs). Water contaminated with sewage harbors pathogens like viruses, bacteria, protozoa, parasitic worms, etc., which are the causal agents of human diseases such as amoebiasis, diarrhea, jaundice, cholera, typhoid. Cadmium causes itai-itai, kidney damage, lung cancer, and many other health-related problems. Mercury contamination of water causes Minamata disease. Nitrates cause a dangerous health issue known as methemoglobinemia, especially in infants, which is commonly called as “blue-baby syndrome.” Blackfoot disease, skin lesions, and cancer risks of lungs, bladder, and skin are the severe health-related issues associated with the exposure to arsenic-polluted water. Use of water contaminated with excessive fluoride causes skeletal fluorosis. Health effects of microplastic exposure include inflammation and tissue damage, toxic chemical release from microplastics, oxidative stress, and microbial contamination. Microplastics also act as vectors for a variety of microorganisms including pathogens causing various diseases. Plasticizers and other toxic compounds in microplastics disturb the endocrine system, disrupting proper hormonal function. Some carcinogenic additives and chemicals become a cause of cancer. Some additives in the human body may have neurotoxic effects, leading to neurocognitive disorders and even Alzheimer’s. Polluted water significantly impacts public health, agriculture, industry, tourism and recreation, property values, environmental remediation costs, etc. and puts an affected society under a sort of stress, negatively impacting overall work output and creativity.