Bioaccumulation is the process by which chemicals are stored in the tissues of living organisms. It is the accumulation of chemicals in the tissue of organisms through any route including, respiration, ingestion or direct contact with contaminated water, sediment and pore water in the sediment. These chemical substances include, pesticides or other chemicals.
The common brushtail possum was introduced to New Zealand in 1837 to establish a fur industry, but in the mild subtropical climate of New Zealand, and with few to no natural predators, it thrived to the extent that it became a major agricultural and conservation pest<span>.</span>