Endocrine disruptor own hormones. These regulation effects are intertwined so that a hormone that is level affected by another hormone in turn affects the levels of multiple other hormones produced by the body itself, leaving no endogenous hormones or traits affected by them unaffected by endocrine disruptors. Most toxicants, including endocrine disruptors, have been claimed to follow a U-shaped dose response curve. This means that very low and very high levels have more effects than mid-level exposure to a toxicant. Endocrine disrupting effects have been noted in animals exposed to environmentally relevant levels of some chemicals. For example, a common flame retardant,
Labial glands Labial glands The labial glands are minor salivary glands situated between the mucous membrane and the orbicularis oris around the orifice of the mouth. They are circular in form, and about the size of small peas; their ducts open by minute orifices upon the mucous membrane. Like the parotid and buccal glands, the labial glands are innervated by parasympathetic fibres that arise in the inferior salivatory nucleus, travel with the glossopharyngeal nerve and lesser petrosal nerve to the otic ganglion, where they synapse and then continue to the labial glands. Sympathetic innervation is mediated by postganglionary fibres which arise in