Table 1 Developmental and psychopathological impact of environmental exposures over different life stages

Fetus

Maternal mal-nutrition

Early brain development, including key serotonergic and dopaminergic signalling systems

Externalizing problems in early childhood [21]

Intra-uterine growth retardation/Low birth weight

Developmental programming of physiological systems

Wide range of cognitive, emotional and behavioural outcomes [22]

Maternal substance use

Later growth and development including trans-generational effects [23]

Wide range of cognitive, emotional and behavioural outcomes

Psychosocial stress during pregnancy/ maternal depression & anxiety

Behavioural disturbances in later childhood [24]

Environmental pollutants – toluene in traffic smoke, organophosphates in pesticides

Developmental neurotoxicity; Neuroimaging evidence of structural abnormalities

Cognitive deficits [25, 26]

Early childhood

Pollutants, environmental toxins – polycyclic aromatic hydrocarbons in biomass fuels, tobacco smoke, arsenic in ground water, fluoride, lead, polychlorinated biphenyls from insulators in electrical equipment, phthalates from plastics and cosmetics

Injury to the developing human brain either through direct toxicity or interactions with the genome [27]

Low verbal IQ [29]; Cognitive deficits among preschool-age children [30]; behavioral abnormalities [31]

Neurotoxicity with effects persistent throughout life [28]

Absence of primary attachment figure/poor parenting

Deficits in cognitive and socio-emotional development [32]

Indiscriminate friendliness, poor peer relationships [33]

Under-nutrition

Synaptic pruning, Myelination, Executive functioning [34, 35]

Risk of emotional and behavioural problems [36]; High prevalence of health-harming behaviours [37]

Childhood & adolescence

Poverty/deprived neighbourhoods

Via parental psychopathology, less positive parenting, neglect, poor monitoring [38]

Higher prevalence of SUDs [39]; various negative behavioural outcomes [40]; Conduct problems [41]

Exposure to war and conflict

Range of psychopathology, including post-traumatic stress disorder [42]

High conflict home environment (parental marital conflict, parental divorce)

Disruptive behaviours [43]

Harsh parenting, physical abuse

Disruptive and emotional psychopathology [44]

Deviant peer relationships

Behavioural reinforcement, exchange of techniques

Delinquentbehaviours [45]

Adolescence

Substance use

Interferes with brain maturation especially in areas affecting self-regulation and control

Substance use disorders and global difficulties in adult functioning [46]