physical growth and development thesis

Student 1 response to the discussion


Research a scholarly journal article on the biological and environmental factors that may impact the physical development of a child. Provide a brief summary of the article. Compare and contrast it to your course readings thus far.

Zeng et al. (2019) studied the associations between heavy metal exposure and physical growth and development in Chinese children. 470 preschool-aged children from Guiyu, an electronic waste exposure area, and Haojiang, the control area, were tested with physical exams and a blood test to measure their birth length and weight, height, weight, body mass index, head circumference, and chest circumference. Their blood was tested for levels of lead, cadmium, chromium, and manganese (Zeng et al., 2019). The results indicated that children in Guiyu had significantly lower birth weights and lengths, body mass indices, and chest circumference. Blood lead levels were also negatively correlated with height, weight, body mass index, head circumference, and chest circumference. Levels of cadmium, chromium, and manganese were not associated with any physical developmental outcomes (Zeng et al., 2019).

Multiple studies have linked high blood lead levels to negative developmental outcomes. The effects of lead exposure can include poor physical outcomes, as demonstrated by Zeng et al. (2019), as well as lower intelligence, lower school achievement, attention deficit hyperactivity disorder, and high blood pressure (Santrock et al., 2021). Lead exposure damages the brain and nervous system, which then leads to slowed growth and development, learning and behavior problems, and possible hearing and speech problems as well (Santrock et al., 2021).


Research consistently shows that living in poverty negatively influences language development. Locate and summarize information that would support this assumption (e.g., journal articles, Centers for Disease Control [CDC], and/or World Health Organization [WHO]). What types of experiences or resources do you feel that children who live in poverty do not experience or receive but children from higher economic statuses benefit from?

One way that living in poverty negatively influences language development is, again, through lead exposure. Children in poverty are at an elevated risk for lead poisoning compared to their peers in higher socioeconomic households (Santrock et al., 2021). This is because most lead exposure comes from swallowing house dust or soil contaminated by lead paint. Children living in poverty are more likely to live in older, unrenovated houses that still have lead paint and lead pipes (Centers for Disease Control and Prevention [CDC], 2021). Households in poverty are also more likely to live in less desirable areas, such as near industrial sites, where children may be exposed to dust from soil with lead from leaded gasoline, aviation fuel, mining, or industries (CDC, 2021). Lead can affect language development by lowering IQ, lowering the ability to focus, slowing development, and causing hearing and speech problems (CDC, 2021).

Children in poverty also may not have access to experiences and resources to assist with language development such as books in the household or a person to consistently read to them. Low-income children are exposed to less language overall and less of the language that promotes school readiness and academic achievement (Santrock et al., 2021). In one study, parents on welfare talked less to their young children, talked less about past events, and provided less elaboration that parents who were professionals (Hart & Risley, (1995); in Santrock et al., 2021). In addition, low-income children may not have access to early intervention services that their wealthier peers might be able to obtain, such as speech therapy, doctor visits, and specialist interventions (Santrock et al., 2021).