SciELO - Scientific Electronic Library Online

vol.109 número9 índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados



Links relacionados

  • Em processo de indexaçãoCitado por Google
  • Em processo de indexaçãoSimilares em Google


SAMJ: South African Medical Journal

versão On-line ISSN 2078-5135
versão impressa ISSN 0256-9574

SAMJ, S. Afr. med. j. vol.109 no.9 Pretoria Set. 2019 



Climate change and adolescents in South Africa: The role of youth activism and the health sector in safeguarding adolescents' health and education



Today's youth will inherit a world made hazardous by greenhouse gases. As a general rule, those chiefly responsible for emitting these gases will be spared the full brunt of their effects. Age has become a clear fault line of this phenomenon: while today's adults will experience some impacts of these emissions, adolescents and future generations will face their full force in time.

The voices of young people are seldom included in discourses around health policy. Recently, however, adolescents have begun to assert their position within the 'climate crisis'.[1] Initiatives like staging a school strike every Friday (#ClimateStrike), forming 'Extinction Rebellion' protests and blocking public sites like the London Tower Bridge have generated considerable momentum. [2 In several countries, adolescents are also employing litigation as a means of holding their governments and the private sector to account, a strategy that may have some merit in South Africa (SA) (see box 'Youth-led litigation against the South African government and private sector: A turning point for securing the future health of children?').[3]

Not all adolescents are equally empowered to take up these challenges, however. There are major gaps in knowledge about climate change among adolescents in many low- and middle-income countries, including SA,[4,5] and climate activism is nascent in these settings.[6]

In SA there are around 10 million adolescents (10 - 19 years), who make up about 20% of the country's population.[7] They already face a gamut of challenges, ranging from HIV infection, sexual and physical violence, teenage pregnancy and substance use to poverty, inequality and gangsterism. Additionally, many schools are unsafe, with overcrowded classrooms and high levels of environmental toxins, and educational outcomes are poor. [8,9]

Overall, the effects of climate change on adolescents, and the effects of heat exposure in particular, are underappreciated. In this commentary we present evidence of how adolescents are already being affected by climate change and how these effects will deepen in the near future (Fig. 1). Many health practitioners have little insight into the impacts of heat on outcomes such as comfort while at school and cognition more generally,[10] education attainment and violence. Even if aware of these issues, they are likely to regard them as being outside the remit of the health sector. Equally, the education sector may not see these matters as health related. We aim to demonstrate the centrality of the health sector to countering climate change impacts on adolescents in SA.


Impacts of climate change on adolescents' health

Changes in climate affect children and adolescents in unique ways, given their dynamic biological, psychosocial and cognitive development.[11] Adolescents and adults have similar physiological thermo-regulatory mechanisms,[12] but adolescents may lag in behavioural thermoregulation, for example owing to inadequate fluid intake.'131 Compared with boys, the effects on girls may be greater, given that they have higher rates of obesity (which compromises thermoregulation), and of mental health conditions and mortality during extreme weather events.[14] Similarly, subgroups of adolescents with limited physical or monetary resources to counter the impacts of climate change, such as those living in extreme poverty or with disabilities, may also be at increased risk.

Generally children spend more time outdoors than adults, raising their exposure to solar ultraviolet radiation and their risks for exertional heat injuries in sports. Additionally, about 20% of children aged 7 - 17 in SA are engaged in some form of economic activity, producing goods for the 'market' or for their own household.[15] About 17% of these children report working in conditions characterised by 'extreme temperatures and humidity', which equates to around 400 000 children at considerable risk for dehydration and heat stress during heatwaves.[15]

Changes in water quality and availability are principal manifestations of climate change, and have implications for adolescent health. Droughts may threaten water security in schools in SA, where water is often drawn from boreholes or even rivers. Floods, however, can also contaminate water with infectious agents and toxins. Further, safe water for sanitation and hygiene is especially important in SA, since around 30% of schools use pit latrines or have no toilet at all.[16] Most water- and foodborne infections, particularly those of bacterial aetiology, are heat sensitive, of particular concern among adolescents given that close contact in schools heightens transmission of infections. High temperatures and temperature variations also exacerbate asthma in adolescents,[17,18] and these associations may be stronger than for other age groups.[19] Dust and pollen increments from climate change, and air pollution in itself, also raise risks for asthma and allergies in adolescents.[20] Importantly, heat raises exposure to environmental toxins, which is worrying as many schools in SA are located near areas with toxic substances, such as heavily trafficked roads, mine dumps and industrial operations.


Click to enlarge


The indirect effects of climate change also warrant mention. The biological and cognitive development of an adolescent occurs in the context of their household, school and community: social disruptions, such as food insecurity, damage to infrastructure and migration, can therefore have a major impact on this age group.

Together, these direct and indirect impacts pose mental health risks for adolescents, including post-traumatic stress disorder, depression, anxiety, sleep disorders and even suicide.[21-23] Heat exposure can also increase irritability, aggression and violence,[24] a major concern given the rates of physical and sexual violence in schools in SA, both pupil-on-pupil and between teacher and pupil. Extreme weather events such as storms, droughts and wildfires have been strongly linked with mental health conditions in adolescents, which commonly persist into adulthood.[25,26] Recent figures from the United Nations show that globally there is at least one climate change disaster every week.[27] Even if these disasters trigger mental health conditions in a small fraction of adolescents, that translates into a massive disease burden.[28]

The mental health and behavioural impacts of climate change are especially pronounced among adolescents who have pre-existing psychological vulnerabilities or resilience deficits.[29] This is highly relevant in SA, where the burden of mental illness among adolescents is among the highest in the world.[30] Early preventive interventions shortly after an extreme weather event, and involving adolescents themselves in disaster risk reduction and recovery, appear important in minimising the occurrence of mental health difficulties.[28]


Heat exposure in schools: 'Sick building syndrome'

While the Department of Basic Education mentions environmental factors such as ventilation and the hazards of non-brick structures in its school infrastructure standards, these have not yet been fully actualised.[31] In many schools, classrooms are made out of converted shipping containers or prefabricated sheeting with corrugated iron roofs. Most container classrooms have poor insulation, little natural ventilation and as many as 50 children in a class, who themselves generate a considerable heat load.[32] In one study in Johannesburg, which has a relatively mild climate, temperatures reached as high as 47.5°C in the containers and the large majority of students reported experiencing heat-health symptoms every day, including drowsiness, poor concentration and thirst.[33] These impacts will be even greater in hotter regions of the country, such as Northern Cape and Limpopo provinces. A study in Cameroon had similar findings, with notably higher symptoms among girls than boys.[34] In both studies, the classroom windows and doors were often kept closed. Furthermore, many adolescents live in housing that is poorly resistant to heat. In informal settlements and some formal low-cost housing developments ('RDP' housing), for example, indoor temperature may be 4 - 5°C warmer than outdoors, conditions hardly conducive to completing homework, preparing for examinations and quality sleep. [35]

A large number of studies have documented the effects of temperature on educational performance, which is influenced not only by the temperature on the day of examinations, but by the total cumulative heat exposure over the academic year.[36,37] In a meta-analysis involving 18 studies, the authors calculated that students in classrooms with an indoor temperature of 30°C scored 20% lower on tests than those in classes around 20°C.[37] The performance of adolescents appears to be more heat sensitive than the performance of adults in occupational settings.[38] Nevertheless, teachers exposed to high temperatures may also become lethargic and irritable.[38]

There are major equity issues at stake here: adolescents who have attended well-resourced schools with temperatures carefully controlled for optimal concentration will compete for jobs or places at university alongside those who wrote school-leaving examinations in temperatures above 40°C, and were drowsy and probably poorly hydrated. That these examinations are written in the summer months in SA further accentuates these concerns.

In classes with poor ventilation, levels of CO2 or stuffiness rise together with temperature, and children experience symptoms characteristic of the 'sick building syndrome'.[39] These symptoms affect concentration and student learning, and even school attendance and rates of asthma attacks.[40-46] Window opening is a key means of removing heat and CO2. However, in towns and cities with high pollution levels, such as Witbank, one of the most polluted towns in the world, doing so would increase exposure to outdoor air pollution. Greenhouse gases and other pollutants in themselves have substantial health consequences and are increasingly viewed as 'secondary smoke' exposures for children, no less harmful or unkind than smoking cigarettes in an adolescent's bedroom.


Interventions to reduce heat stress in schools

The interventions proposed below are based on the premise that thermal comfort drives learning, reduces heat-related aggression, and improves comfort and wellbeing for scholars and teachers. These interventions require supportive policy frameworks and efforts by the departments of Health and Basic Education to mainstream climate change adaptation interventions and awareness-raising activities into schools.


Figure 2


Longer-term initiatives to make the built environment more heat resistant are clearly critical, especially replacing containers and prefabricated buildings with brick classrooms. Until that occurs, behavioural and institutional actions could be taken (Fig. 3).[47] Few interventional studies have addressed this topic, however. In one study in Costa Rica, learning outcomes improved after air conditioning was installed in the classrooms.[48] Studies in high-income countries have also shown that the effects of heat on exam performance can be ameliorated by air conditioning'[36] and mechanical ventilation.'49- But further research is needed to identify effective interventions other than air conditioning. These could potentially include providing cold water at regular prespecified intervals, use of the ancient Egyptian method of applying damp cloths to the body, which cools as the water evaporates, and improved natural ventilation, which also lowers risks of tuberculosis transmission in schools.[50,51] Schools could also consider substituting closed shoes with sandals, using light-coloured, loose clothing, and adapting school hours during the hottest seasons, with either earlier starting times or a longer lunchtime break and later finishing hours. Planting trees in school grounds provides shade and cooling, and other health and environmental benefits. A 'cooling room' could be developed in the school, where, for example, fans are installed on the walls, the roofs are painted white, plants are hung on the walls and trees are planted nearby. During extremely hot days pupils could spend time in the cooling room during breaks or after school, and the room could be used for examinations.

One possible study design could involve randomising pupils to write examinations in classes where some of these interventions have been applied and comparing them with pupils in existing classrooms without such interventions. Showing that a few interventions can alter educational outcomes could provide impetus for implementing and scaling up climate adaptation activities in schools.

Implementing these interventions may face challenges, however, as many people view heat only as a nuisance factor or a 'normal' occurrence to be tolerated, rather than as a modifiable risk factor that can influence health and learning. Ideally, interventions need to be co-designed with adolescents, teachers, caregivers and other stakeholders to enhance acceptability and buy-in. For example, while there may be advantages to holding classes outdoors under shading on hot days, outdoor classes have come to symbolise failed school infrastructure in SA, and may be viewed as such, rather than as a heat-reducing measure.



The quality of the school environment and experiences in this setting may set the scene for adolescents' health and wellbeing as adults, and for their capacity to achieve their full potential in life and to contribute to society and national economies. Climate change adaptation in schools may be an under-recognised but important strategy for countering inequities in SA. The pre-existing mental health vulnerabilities of adolescents and challenges in the education sector in SA mean that effects of climate change may threaten the already fragile resilience of adolescents in the country.

Further research is needed to identify which interventions can most effectively reduce the impacts of heat exposure at school, and ensure that fewer adolescents in SA have to contend with 'sick buildings' in their learning environment. As part of this, we need to gauge how much adolescents understand about climate change, cultivate their activism in this field, and document the impacts of heat exposure on learning, mental health and violence in schools.

In SA, adolescents stood up against apartheid. The country now needs its own brand of youth activism that stands up against environmental destruction. Safeguarding schools against the health and education impacts of heat, allied with increasing awareness of climate change, is a good place to start.

Acknowledgements. We thank Lois Harden, Faculty of Health Sciences, University of the Witwatersrand, for input on the physiology of thermoregulation in adolescents. Also thanks to Anita Kleinsmidt and Timothy Lloyd for review of the climate law text.


M F Chersich 1 F Scorgie,1 C Y Wright,2, 3 S Mullick,1 A Mathee,3,4 J Hess,5 M Richter,6 H Rees1

1 Wits RHI (Wits Reproductive Health and HIV Institute), Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa

2 Department of Geography, Geoinformatics and Meteorology, Faculty of Natural and Agricultural Sciences, University of Pretoria, South Africa

3 Environment and Health Research Unit, South African Medical Research Council, Pretoria, South Africa

4 Environmental Health Department, Faculty of Health Sciences, University of Johannesburg, South Africa

5 Departments of Emergency Medicine, Environmental and Occupational Health Sciences, and Global Health, Center for Health and the Global Environment (CHanGE), Schools of Medicine and Public Health, University of Washington, USA

6 Sonke Gender Justice, South Africa; School of Public Health and Family Medicine, University of Cape Town, South Africa; and African Centre for Migration and Society, University of the Witwatersrand, Johannesburg, South Africa



1. Campbell E, Skovdal M, Campbell C. Ethiopian students' relationship with their environment: Implications for environmental and climate adaptation programmes. Children's Geographies 2013;11(4):436-460.        [ Links ]

2. Stott R, Smith R, Williams R, Godlee F. Schoolchildren's activism is a lesson for health professionals. BMJ 2019;365:l1938.        [ Links ]

3. Marris E. US Supreme Court allows historic kids' climate lawsuit to go forward. Nature 2018;563(7730):163-164.        [ Links ]

4. Mugambiwa SS, Dzomonda O. Climate change and vulnerability discourse by students at a South African university. Jamba (Potchefstroom, South Africa) 2018;10(1):a476.        [ Links ]

5. Sulistyawati S, Mulasari SA, Sukesi TW Assessment of knowledge regarding climate change and health among adolescents in Yogyakarta, Indonesia. J Environ Public Health 2018;2018:9716831.        [ Links ]

6. Hendricks A, Postman Z, Binda M. South African youths march for action against climate change. GroundUp. 2019. (accessed 9 July 2019).         [ Links ]

7. Statistics South Africa. Demographic profile of adolescents in South Africa. Report 03-00-10. Pretoria: Stats SA, 2018. (accessed 9 July 2019).         [ Links ]

8. Ncontsa VN, Shumba V. The nature, causes and effects of school violence in South African high schools. S Afr J Educ 2013;33(3).         [ Links ]

9. Marais P. "We can't believe what we see': Overcrowded classrooms through the eyes of student teachers. S Afr J Educ 2016;36(2).         [ Links ]

10. Cedeno Laurent JG, Williams A, Oulhote Y, Zanobetti A, Allen JG, Spengler JD. Reduced cognitive function during a heat wave among residents of non-air-conditioned buildings: An observational study of young adults in the summer of 2016. PLoS Med 2018;15(7):e1002605.        [ Links ]

11. Sheffield PE, Landrigan PJ. Global climate change and children's health: Threats and strategies for prevention. Environ Health Perspect 2011;119(3):291-298.        [ Links ]

12. Falk B, Dotan R Children's thermoregulation during exercise in the heat: A revisit. Appl Physiol Nutr Metab 2008;33(2):420-427.        [ Links ]

13. Somboonwong J, Sanguanrungsirikul S, Pitayanon C. Heat illness schoolboys participating in physical education class in tropical climate: An analytical surveillance in prospective descriptive study. BMJ Open 2012;2(4).        [ Links ]

14. Atkinson HG, Bruce J. Adolescent girls, human rights and the expanding climate emergency. Ann Glob Health 2015;81(3):323-330.        [ Links ]

15. Statistics South Africa. Survey of activities of young people, 2015. Statistical release P0212. Pretoria: Stats SA, 2017. (accessed 9 July 2019).         [ Links ]

16. United Nations Children's Fund (UNICEF). WASH: Ensuring safe water, sanitation and hygiene help children to survive and thrive. 2017. (accessed 9 July 2019).         [ Links ]

17. Li K, Ni H, Yang Z, et al Effects of temperature variation between neighbouring days on daily hospital visits for childhood asthma: A time-series analysis. Public Health 2016;136:133-140. https://doiorg/10.1016/j.puhe.2016.04.002        [ Links ]

18. O'Lenick CR, Winquist A, Chang HH, et al. Evaluation of individual and area-level factors as modifiers of the association between warm-season temperature and pediatric asthma morbidity in Atlanta, GA. Environ Res 2017;156:132-144.        [ Links ]

19. Soneja S, Jiang C, Fisher J, Upperman CR, Mitchell C, Sapkota A. Exposure to extreme heat and precipitation events associated with increased risk of hospitalization for asthma in Maryland, U.S.A.Environ Health 2016;15:57.        [ Links ]

20. Zhang Y, Bielory L, Mi Z, Cai T, Robock A, Georgopoulos P. Allergenic pollen season variations in the past two decades under changing climate in the United States. Glob Chang Biol 2015;21(4):1581-1589.        [ Links ]

21. Burke SEL, Sanson AV, van Hoorn J. The psychological effects of climate change on children. Curr Psychiatry Rep 2018;20(5):35.        [ Links ]

22. Younan D, Li L, Tuvblad C, et al. Long-term ambient temperature and externalizing behaviors in adolescents. Am J Epidemiol 2018;187(9):1931-1941.        [ Links ]

23. Kim Y, Kim H, Honda Y, et al. Suicide and ambient temperature in East Asian countries: A time-stratified case-crossover analysis. Environ Health Perspect 2016;124(1):75-80.        [ Links ]

24. Chersich MF, Swift CP, Edelstein I, et al. Violence in hot weather: Will climate change exacerbate rates of violence in South Africa? S Afr Med J 2019;109(7):447-449.        [ Links ]

25. Dean JG, Stain HJ. Mental health impact for adolescents living with prolonged drought. Aust J Rural Health 2010;18(1):32-37.        [ Links ]

26. Austin EK, Handley T, Kiem AS, et al. Drought-related stress among farmers: Findings from the Australian Rural Mental Health Study. Med J Aust 2018;209(4):159-165.        [ Links ]

27. The Guardian. One climate crisis disaster happening every week, UN warns. 2018. (accessed 9 July 2019).         [ Links ]

28. Dyregrov A, Yule W, Olff M. Children and natural disasters. Eur J Psychotraumatol 2018;9(Suppl 2):1500823.        [ Links ]

29. Majeed H, Lee J. The impact of climate change on youth depression and mental health. Lancet Planetary Health 2017;1(3):e94-e95.        [ Links ]

30. Cheng Y, Li X, Lou C, et al. The association between social support and mental health among vulnerable adolescents in five cities: Findings from the study of the well-being of adolescents in vulnerable environments. J Adolesc Health 2014;55(6 Suppl):S31-S38.        [ Links ]

31. South Africa. South African Schools Act, 1996 (Act No. 84 of 1996): Regulations relating to minimum uniform norms and standards for public school infrastructure. Government Gazette No. 37081, 2013.         [ Links ]

32. Ntongana T. "We are 52 students in one container. GroundUp. 2018. (accessed 9 July 2019).         [ Links ]

33. Bidassey-Manilal S, Wright CY, Engelbrecht JC, Albers PN, Garland RM, Matooane M. Students' perceived heat-health symptoms increased with warmer classroom temperatures. Int J Environ Res Public Health 2016;13(6):566.        [ Links ]

34. Dapi LN, Rocklov J, Nguefack-Tsague G, Tetanye E, Kjellstrom T. Heat impact on schoolchildren in Cameroon, Africa: Potential health threat from climate change. Global Health Action 2010;3:1.        [ Links ]

35. Naicker N, Teare J, Balakrishna Y, Wright CY, Mathee A. Indoor temperatures in low cost housing in Johannesburg, South Africa. Int J Environ Res Public Health 2017;14(11):1310.        [ Links ]

36. Goodman J, Hurwitz M, Park J, Smith J. Heat and learning. HKS Working Paper No. RWP18-014. 2018. (accessed 9 July 2019).         [ Links ]

37. Wargocki P, Porras-Salazar JA, Contreras-Espinoza S. The relationship between classroom temperature and children's performance in school. Build Environ 2019;157(15):197-205.        [ Links ]

38. International Labour Organization. Working on a warmer planet: The impact of heat stress on labour productivity and decent work. 2019. (accessed 9 July 2019).         [ Links ]

39. United States Environmental Protection Agency. Indoor Air Facts No. 4 (revised): Sick building syndrome. 1991. (accessed 9 July 2019).         [ Links ]

40. Wargocki P, Wyon DP. The effects of outdoor air supply rate and supply air filter condition in classrooms on the performance of schoolwork by children. HVAC&R Res 2007;13(2):165-191.        [ Links ]

41. Haverinen-Shaughnessy U, Shaughnessy RJ. Effects of classroom ventilation rate and temperature on students' test scores. PloS One 2015;10(8):e0136165.        [ Links ]

42. Twardella D, Matzen W, Lahrz T, et al. Effect of classroom air quality on students' concentration: Results of a cluster-randomized cross-over experimental study. Indoor Air 2012;22(5):378-387.        [ Links ]

43. Mendell MJ, Eliseeva EA, Davies MM, Lobscheid A. Do classroom ventilation rates in California elementary schools influence standardized test scores? Results from a prospective study. Indoor Air 2016;26(4):546-557.        [ Links ]

44. Gaihre S, Semple S, Miller J, Fielding S, Turner S. Classroom carbon dioxide concentration, school attendance, and educational attainment. J School Health 2014;84(9):569-574.        [ Links ]

45. Shendell DG, Prill R, Fisk WJ, Apte MG, Blake D, Faulkner D. Associations between classroom CO2 concentrations and student attendance in Washington and Idaho. Indoor Air 2004;14(5):333-341.        [ Links ]

46. Mi YH, Norback D, Tao J, Mi YL, Ferm M. Current asthma and respiratory symptoms among pupils in Shanghai, China: Influence of building ventilation, nitrogen dioxide, ozone, and formaldehyde in classrooms. Indoor Air 2006;16(6):454-464.        [ Links ]

47. Hyndman B. "Heat-smart' schools during physical education (PE) activities: Developing a policy to protect students from extreme heat. Learning Communities: International Journal of Learning in Social Contexts (Special Issue: 2017 30th ACHPER International Conference), 21, 56-72. 2017.        [ Links ]

48. Porras-Salazar JA, Wyon DP, Piderit-Moreno B, Contreras-Espinoza S, Wargocki P. Reducing classroom temperature in a tropical climate improved the thermal comfort and the performance of elementary school pupils. Indoor Air 2018;28(6):892-904.        [ Links ]

49. Petersen S, Jensen KL, Pedersen AL, Rasmussen HS. The effect of increased classroom ventilation rate indicated by reduced concentration on the performance of schoolwork by children. Indoor Air 2016;26(3):366-379.        [ Links ]

50. Public Health England. Looking after children and those in early years settings during heatwaves: Guidance for teachers and professionals. 2015. ile/428850/Looking_After_Children_Heat_PHE_AC_AB_Publications_MP_JRM_FINAL.PDF (accessed 9 July 2019).         [ Links ]

51. Richardson ET, Morrow CD, Kalil DB, Ginsberg S, Bekker LG, Wood R. Shared air: A renewed focus on ventilation for the prevention of tuberculosis transmission. PloS One 2014;9(5):e96334.        [ Links ]

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons