Final answer:
Toxicants that are non-biodegradable and lipid-soluble are likely to bioaccumulate in animals. Persistent organic pollutants like DDT, dioxin, and PCBs are examples of such chemicals that persist in the environment, biomagnify through the food chain, and pose health risks.
Step-by-step explanation:
The properties of toxicants likely to build up in animals through bioaccumulation are non-biodegradable, lipid-soluble. These chemicals are persistent organic pollutants (POPs) such as DDT, dioxin, and PCBs, which are long-lived in the environment, biomagnify through the food chain, and can be toxic to organisms at high trophic levels, including humans. For instance, mercury from polluted water can accumulate in swordfish to levels toxic to humans. Therefore, these contaminants register more in the tissues of organisms higher up the food chain due to their inability to be broken down and their propensity to dissolve in fats.
Furthermore, many of these substances such as heavy metals and pesticides are introduced into the ecosystem through various industrial and agricultural practices which do not have an evolutionary backdrop, making them particularly hazardous as there is no natural mechanism in many organisms to process and eliminate them. The bioaccumulative nature of these substances poses significant health risks as they can lead to accumulation in human tissue and cause adverse health effects, including endocrine disruption and birth defects.