Author: Professor John Devaney

John holds the Centenary Chair of Social Work at the University of Edinburgh, having previously worked at Queen's University Belfast. He is a qualified social worker, who practised for nearly twenty years before entering academia on a full-time basis in 2006.

John's research focuses mainly on the broad area of family violence, with a particular focus on child homicide, child maltreatment, child welfare policy, domestic violence, and the impact of adversity in childhood across the lifecourse. He has an interest in comparative social policy, evaluations of practice and interventions, and policy development. He has undertaken a range of research studies in both the UK and internationally, funded by research councils, government departments and philanthropic organisations.

The toxicity of the term ‘toxic stress’


During the 1990s the National Institutes of Health in the United States of America invested significant resources into understanding both normal and pathologic neuronal development and function, in what was to become known as the “Decade of the Brain”. This coincided with advances in neuroscience at both a cellular and molecular level, and the development of a number of theories about the factors and processes both promoting and impeding brain development, particularly in children. One such stream of work sought to explore the ‘nature v nurture’ debate as to the factors most likely to influence who we are, and what we become. Although genetic variability has been shown to play a role in how we all respond to stress, there has been growing debate of the potential impact of early life experiences and environmental influences. Some authors have rightly expressed caution about this ‘new’ science, expressing concern that “there is a clear focus on reproduction and maternal behaviours, paralleled by a pervasive lack of explicit reference to the alleviation of poverty and social disadvantage” (White and Wastell, 2017), and a growing, but as yet, inconclusive evidence base about whether we know enough about the actual development of the brain to rush headlong into new ways of working with individuals and groups (e.g. manualised programmes), at the expense of doing other things (e.g. poverty alleviation).

However, there is unanimity that seeking to prevent, or at least minimise the impact on children of experiencing adversity should be a goal of any society. Yet, the adversity in itself may not necessarily be a bad thing – rather, it is how the adversity impacts an individual, and no two individuals may be impacted in the same way.

The National Scientific Council on the Developing Child proposed a conceptual taxonomy comprising of three distinct types of stress responses (in contrast to the actual stressors themselves) in young children—positive, tolerable, and toxic—on the basis of expected differences in their potential to cause enduring negative disruptions in children’s social, emotional and physiological systems as a result of the intensity and duration of the response to the stressor (Shonkoff et al., 2012). Toxic stress can result from strong, frequent, or prolonged activation of the body’s stress response systems in the absence of the buffering protection of a supportive, (usually adult) relationship. As Shonkoff and colleagues (2012) note:

“The potential consequences of toxic stress in early childhood for the pathogenesis of adult disease are considerable. At the behavioral level, there is extensive evidence of a strong link between early adversity and a wide range of health-threatening behaviors. At the biological level, there is growing documentation of the extent to which both the cumulative burden of stress over time (eg, from chronic maltreatment) and the timing of specific environmental insults during sensitive developmental periods (eg, from first trimester rubella or prenatal alcohol exposure) can create structural and functional disruptions that lead to a wide range of physical and mental illnesses later in adult life.”

However, while there is a growing consensus that parents, professionals and services should be alert to our growing understanding of child to adult development in the fullest sense, there is also a concern about how we use, and misuse our knowledge on these matters. For example, the term ‘toxic stress’ has become increasingly misused. Rather than describing a response to a stressor, the term is now used to describe the stressor itself, with a particular focus on the idea of the ‘toxic trio’ of parental substance misuse, parental mental illness and intimate partner violence. While there is a good evidence base about the potential for children who live with parents or carers experiencing one or more of these difficulties to be impacted, the misuse of language could give the impression that all children living in such circumstances may be negatively affected, and that any negative affect will stunt their development. This was never the intention of those who coined the term, and in many ways has undermined the important ideas at the heart of the argument. That is, that some stressors have the potential to become toxic to the child’s positive development if not addressed, or minimised by other protective factors. As such, I have sympathy for those who have sought to reject the use of the terms toxic stress and the toxic trio in the sense that they can stigmatise individuals and imply a universality of experience which doesn’t exist. However, I also feel torn by the rejection of the way the term is used to also imply a rejection of the underlying premise – which is that we should seek to minimise children’s exposure to adversity, but most importantly, when children do experience adversity they deserve and require our support to buffer them from the long term consequences that may otherwise endure.


Shonkoff, J.P., Garner, A.S., Siegel, B.S., Dobbins, M.I., Earls, M.F., McGuinn, L., Pascoe, J., Wood, D.L., Committee on Psychosocial Aspects of Child and Family Health and Committee on Early Childhood, Adoption, and Dependent Care (2012). The lifelong effects of early childhood adversity and toxic stress. Pediatrics, 129(1), pp.e232-e246.

White, S. J., & Wastell, D. G. (2017). Epigenetics prematurely born (e): Social work and the malleable gene. British Journal of Social Work, 47(8), 2256-2272.