LAUSR

Importantly, GABAA receptors act differently during development compared to adulthood; the early exposure leads to excitation rather than inhibition of GABAA receptors. This excitation, together with NMDA receptor activation, may potentially trigger excess apoptosis affecting neural development. Conclusions: Specific organic solvents (n-hexane; the aromatic hydrocarbons benzene, toluene, styrene, and xylene; the halogenated solvents trichloroethylene and 1-bromopropane; and alcohols n-propanol and n-butanol) display narcotic effects after acute exposure, NT or narcosis after repeated dosing, and DNT, suggesting a possible link between narcosis and (D)NT. Most of the investigated substances with acute narcotic effects did not show NT in adult animals or DNT, but investigations for DNT appear often lacking, potentially due to lack of identified concern from studies in adult animals or structurally similar substances. It is hypothesised that early interaction with GABAA and/or NMDA receptors might mechanistically explain (D)NT. However, a clear and undisputed mechanistic link between narcosis/anaesthesia and (D)NT has not been established in the literature as yet. On a general level, it cannot be concluded that narcotic effects exerted by organic solvents after acute or repeated exposure are automatically linked to NT/DNT; it is recognised, though, that available information on effects following early exposure is scarce.