Wildlife in Britain and Ireland has been shown to be adversely affected by exposure to chemicals that alter the balance of hormones in the body. Effects in wildlife are predominantly, but not exclusively, found in species living in and/or closely associated with the aquatic environment. The best-known examples of this so-called phenomenon of endocrine disruption in British and Irish wildlife include eggshell thinning in birds of prey, imposex in marine snails, where male sex organs grow in females, and alteration of sexual development in fish, including intersex where both male and female sex tissues are contained within an individual that is normally single sexed. Some of these effects have resulted in population-level consequences and in marine snails they have even caused localised population extinctions. The causative chemicals of endocrine disruption in wildlife are wide ranging and they include natural and synthetic steroids, pesticides and a variety of industrial chemicals. Adding to the complexity of the problem, most wildlife populations are exposed to mixtures of these hormone-disrupting chemicals (HDCs) that can accumulate in their bodies and are additive in their effects in the body. Such exposures are well illustrated in seals and otters that have been shown to contain high body concentrations of organochlorines, polybrominated diphenyl ethers (PBDEs, used as flame retardants) and polychlorinated biphenyls (PCBs) in their fatty tissues, all of which disrupt how hormones work. […]