Pharmaceutical residues, including those from drugs such as antibiotics, hormones, and painkillers, are increasingly present in tap water. These contaminants enter water supplies primarily through human excretion and improper disposal of drugs, which wastewater treatment plants may not completely remove. The presence of pharmaceuticals in drinking water raises concerns about long-term exposure, even at low concentrations. Antibiotic residues can contribute to the development of antibiotic-resistant bacteria, which poses a significant threat to public health. Hormonal residues, such as those from birth control pills, can disrupt the endocrine system, which can affect reproductive health and development. The cumulative impact of these substances, particularly with prolonged exposure, is still being studied, but the potential for adverse health effects, particularly in sensitive populations such as pregnant women and children, is a growing concern. This highlights the need for improved water treatment technologies and responsible drug disposal practices.

Industrial activities can introduce pollutants such as heavy metals (e.g., mercury, cadmium), volatile organic compounds (VOCs), and pharmaceuticals into water sources. These pollutants can enter tap water through runoff or discharge from factories. Chronic exposure to industrial pollutants, even at low concentrations, can lead to serious health problems, including cancer, liver and kidney damage, and reproductive problems. Although water treatment plants aim to remove these contaminants, some may still be present, raising concerns about long-term exposure.