A new study has found that open defecation, which is still commonly practised in Cambodia, has direct links to reduced heights in children, with a decrease in the practice over five years leading to increases in height.

The study, published next month in Economics and Human Biology, explains that unsanitary toilet conditions can cause diarrhea, intestinal parasites and intestinal disease, all of which can lead to stunted growth.

It says that open defecation in Cambodia dropped between 2005 and 2010, from 77 percent of households to 66 percent, and that the average heights of children aged under 5 increased significantly during the same period.

“The reduction in children’s exposure to open defecation can statistically account for much or all of the increase in average child height between 2005 and 2010,” it found, while acknowledging other factors may have affected changes in heights alongside sanitation.

It says a vast array of other variables – including the height of the mother, vaccination data, household wealth and socio-economic status and milk consumption – were controlled for, and open defecation remained “highly statistically significant in all specifications”.

The study also found open defecation within a community was more indicative of child height than sanitation in a particular child’s own home. “Open defecation in the community predicts child height, regardless of whether the household defecates in the open,” it says.

Given this communal aspect of the issue, the study repeatedly calls on the development of new public policies to address the long-running problem of open defecation, but does not give any particular recommendations.

Hang Hybunna, a researcher with Plan International, an organisation aimed at promoting child rights and combating poverty, said he agreed with the study’s conclusions, and that the prevalence of open defecation has long been a “good indicator” of overall health.

Plan International is currently working in conjunction with the Ministry of Rural Development to bring sanitary toilets to over 600,000 households by 2019, he said, noting that even one household without a toilet could contaminate the water supply of its whole community.

The researcher added that his organization does not recognise any community as being open-defecation free until 85 percent of the community has access to its own toilet and the other 15 percent has access to public toilets.