The Heat Is On: Complexities of Aquatic Endocrine Disruption in a Changing Global Climate

The planet is in the midst of a shift in global climate norms due to the anthropogenic addition of heat-trapping greenhouse gases to the atmosphere. As such, it is important to consider the significant alterations to environmental conditions occurring in aquatic ecosystems, when evaluating the responses of aquatic organisms to endocrine disrupting compounds (EDCs). In this review we summarize the current body of literature on concurrent exposure to abiotic factors associated with global climate change (GCC; e.g., temperature, acidification) and selected EDCs in fish and invertebrates. Evidence suggests that the assessment of risk to aquatic organisms should be expanded to include evaluations across temperature, oxygen, pH, and salinity gradients, since responses differ depending on the environmental conditions at which exposures are conducted. Ultimately, fundamental homeostatic processes are challenged as environmental conditions become more stressful, reducing the ability to cope with chemical exposure, while chemical exposure simultaneously interferes with the ability to maintain homeostasis. Many effects are dependent on life stage, with early life stages being more sensitive to exposure than adults in many cases. Many organisms undergo physiological trade-offs when exposed concurrently to GCC-related stressors and EDCs, sometimes only possessing the resources to deal with the most immediate threat. Furthermore, responses are dependent on environmental fate, which can be influenced by factors associated with GCC. Ultimately, the aims of this review are to summarize the current state of knowledge on exposure to EDCs in a shifting climate, to highlight current gaps in knowledge, and to offer direction going forward for scientists and managers in this age of uncertainty.