Impact of the plastic biosand water filter on E. coli levels of children's toys: A pilot study

Introduction: There is growing evidence that household water treatment interventions reduce diarrheal disease risks and improve microbiological water quality. However, few studies have examined the impact of water treatment interventions on household-level hygiene and sanitation. This study examined the impact of a household water treatment technology, the plastic biosand filter (BSF), on the levels of E. coli bacteria found on existing and introduced children's toys in households with and without the plastic BSF in Santa Rosa de Copan, Honduras.

Methods: As part of a randomized controlled trial of the plastic BSF, existing toys were collected from households and a new toy was introduced into households for two weeks. Upon collection, toys were immersed in a rinse solution which was assayed for total coliforms and E. coli.

Results and Conclusions: Preliminary analysis suggests a significantly lower concentration of E. coli on existing toys collected from households with BSFs as compared to households without BSFs. Average concentrations were 4 and 16 E. coli MPN/100mL of rinse solution for BSF and non-BSF households respectively. E. coli concentrations on newly introduced toys were significantly lower for both types of households: 2 and 1.5 E. coli MPN/100mL for BSF and non-BSF households, a non-significant difference between the groups.

Results suggest that children's toys have various levels of contamination possibly predictive of household hygiene/sanitation. However the variation in results indicates the need for additional information regarding levels of contamination of introduced toys over time, if this approach is to be used diagnostically in future research.