Man and animals are sporadically exposed to mycotoxins (the secondary metabolites of moulds), which include those produced in damp and cool environment by the almost ubiquitous soil-microfungi, the Fusaria. Perinatal exposure to the mycotoxins may cause damage to many organs, including the CNS and those which are targets for oestrogenic agents. Depending on the levels of the mycotoxins and the time of their action, the effects may manifest themselves as neonatal abnormalities, or as neurological and behavioural anomalies and chronic disorders later in life. The relationship between the anatomical and behavioural development of individuals and their perinatal exposure to fusarial mycotoxins requires further investigation.