Lipophilic contaminants influence cold tolerance of invertebrates through changes in cell membrane fluidity

Contaminants taken up by living organisms in the environment as a result of anthropogenic contamination can reduce the tolerance of natural stressors, e.g., low temperatures, but the physiological mechanisms behind these interactions of effects are poorly understood. The tolerance to low temperatures of organisms that cannot regulate their body temperature (ectotherms) depends on their ability to increase the fluidity of their cellular membranes at low temperatures. Our study shows that contaminants accumulating in lipids of organisms alter the physical state of their membranes simply by being present. Contaminants of varying chemical structures can alter the membrane fluidity in either direction and correspondingly modulate the cold tolerance of intact animals.