Child environmental exposures to water and sand at the beach: Findings from studies of over 68,000 subjects at 12 beaches

Abstract

Swimming and recreating in lakes, oceans, and rivers is common, yet the literature suggests children may be at greater risk of illness following such exposures. These effects might be due to differences in immunity or differing behavioral factors such as poorer hygiene, longer exposures to, and greater ingestion of potentially contaminated water and sand. We pooled data from 12 prospective cohorts (n=68,685) to examine exposures to potentially contaminated media such as beach water and sand, among children compared to adults, and conducted a simulation using self-reported time spent in the water and volume of water swallowed per minute by age, to estimate the total volume of water swallowed per swimming event by age category. Children 4–7 and 8–12 had the highest exposures to water, sand, and algae compared to other age groups. Based on our simulation, we found that children (6–12) swallow a median of 36mL (90th percentile= 150 mL), while adults 35 and over swallow 9 mL (90th percentile=64 mL) per swimming event, with male children swallowing a greater amount of water compared to females. These estimates may help to reduce uncertainty surrounding routes and durations of recreational exposures and can support the development of chemical and microbial risk assessments.

Children Exposure-Related Behavior Patterns and Risk Perception Associated with Recreational Beach Use

“…A number of studies have found illnesses following beach swimming and linked to presence of indicator bacteria levels, where symptoms include diarrhea and rashes for example [28,29], although sometimes the association was limited or not found [30,31]. Deflorio-Barker et al [32] examined 12 studies to estimate the ingestion of water, sand, or algae and potential relationship to gastrointestinal illnesses. Young children aged 4–12 swallowed a greater amount of water for example compared to other age groups, increasing their potential exposures [32].…”

“…Deflorio-Barker et al [32] examined 12 studies to estimate the ingestion of water, sand, or algae and potential relationship to gastrointestinal illnesses. Young children aged 4–12 swallowed a greater amount of water for example compared to other age groups, increasing their potential exposures [32].…”

Estimating Health Risks to Children Associated with Recreational Play on Oil Spill-Contaminated Beaches

“…This comparative analysis shows that the estimated cancer risks are sensitive to population-specific factors, particularly for exposure frequency. The study of children’s environmental health is often focused on assessing health consequences associated with inhalation exposure in outdoor environments, where children engage in physical activity [ 46 ]. However, the combination of crawling, non-dietary ingestion, and potential contamination of beach sand broaden the scope of potential health risks to children playing on a beach [ 21 , 47 ].…”

Norovirus Outbreak Associated with Swimming in a Recreational Lake Not Influenced by External Human Fecal Sources in The Netherlands, August 2012

“…The epidemiological investigation showed that most of the patients were children. It has been demonstrated that, while swimming, compared to adults, children spend more time in the water and ingest a larger volume of water, thus increasing their exposure [ 26 , 27 ] and resulting in a higher infection risk and attributable disease burden [ 28 ]. High exposure of children in combination with the low infectious dose of NoV [ 2 ] and the incompletely developed immune system in young children explain the high number of affected children.…”