Children’s Vulnerability to Environmental Exposures: Toxic

Shidonna Raven
2 hours ago
3 min read

Oct 14m 2010

Source: NIH

National Library of Medicine

National Center for Biotechnology Information

Photo Source: Unsplash

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Toxic exposures

Children warrant special consideration when quantifying the impact of potential toxic exposures because of their potential increased susceptibility to negative health effects during their rapid growth and development and greater exposures per body weight. Changes in temperature, humidity, and the hydrologic cycle will affect patterns of exposure to chemicals used in food production and other pest control (Confalonieri et al. 2007). An investigation into agricultural pesticide use and temperature and precipitation changes showed an overall increase in cost expected from likely climatic changes (Chen and McCarl 2001). Although most current pesticides are not as persistent or bioaccumulative as those used in the past, their water solubility increases the risk of water contamination, particularly after extreme precipitation events (Donald et al. 2005; Dwight et al. 2002). The extent of human exposure and health effects under future climate change will depend on adoption of less-toxic practices that account for changes in such factors as temperature and precipitation (Boxall et al. 2009).

Chemicals known as persistent organic pollutants (POPs) last for decades without biodegrading. Global surface temperatures, wind patterns, animal migratory patterns, and global ice volume play a role in the distribution of these chemicals (Carrie et al. 2010). Climate change is expected to result in a changing global distribution of heavy metals (e.g., mercury) and POPs as well as altered biotransformation (Booth and Zeller 2005; Noyes et al. 2009). Some climate factors will be expected to speed the transformation process, thereby decreasing the global load of these chemicals, but the altered distribution could mean that some regions of the world experience increased deposition. POPs and other global pollutants such as mercury and lead are already known to have both acute and chronic effects on children. In addition to neurodevelopmental disorders, the health effects from these varied chemicals include endocrine disruption and carcinogenicity (Diamanti-Kandarakis et al. 2009; Eskenazi et al. 2009; Makalinao and Woolf 2005).

Another potential climate-related change in toxic exposure could result from increased contamination in grain and legume crops by mycotoxin-producing fungi, with both acute and chronic health effects in livestock and humans. Aflatoxin (one type of mycotoxin) is produced by Aspergillus species. Risk of contamination depends on many factors such as regional climate, preseason precipitation, minimum and maximum daily temperature, and daily net evaporation (Ono et al. 1999; Strosnider et al. 2006). More than four billion people in developing countries are at risk of chronic exposure to aflatoxin (Williams et al. 2004), which increases the risk of hepatocellular carcinoma, impaired growth, and immune suppression (with unknown clinical significance). During acute aflatoxicosis outbreaks manifesting as hepatitis and jaundice, children have a higher reported mortality rate (Strosnider et al. 2006; Williams et al. 2004). Other health effects of mycotoxins include other cancers, ergotism, and higher rates of birth defects (Etzel 2002). Research and policy change will be necessary to avoid health effects of changing exposure to natural and man-made agricultural contamination (Boxall et al. 2009).