Which of the following are major types of aquatic pollutants?

Chemical pollutants and biological pollutants are indeed considered major types of aquatic pollutants.

Chemical pollutants encompass a wide range of harmful substances, including heavy metals, pesticides, pharmaceuticals, and industrial chemicals, that can enter water bodies through various routes such as agricultural runoff, industrial discharges, and sewage. These substances can cause detrimental effects on aquatic life, disrupt ecosystems, and pose health risks to humans.

Biological pollutants refer to pathogens and invasive species that can adversely affect native aquatic organisms and human health. Examples include bacteria, viruses, and protozoans, which can enter water sources through sewage contamination or runoff, leading to waterborne diseases.

In contrast, while physical pollutants (such as plastics and sediments) and thermal pollutants (which are typically associated with changes in water temperature) are important environmental concerns, they don't encapsulate the major categories that include the broad spectrum of harmful chemicals and biological threats that primarily impact aquatic systems. This context emphasizes why the combination of chemical and biological pollutants forms a significant focus in discussions of aquatic pollution.