Q7) Based on the information above, the environmental epidemiologists concluded that human exposure to DDT led to overweight or obesity of adults. However, this conclusion may be spurious or ostensible because it could suffer various biases and errors, i.e., there exist other possible explanations for the observed association between DDT exposure and obesity. Please link the alternative mechanisms described below with the types of bias or error based on what you learned in this course. People who eat more lipid-rich food are more likely to be overweight or Sampling bias obese after 5 years, and because of the bioaccumulation of DDT in lipid, these people ingest more DDT and have high DDT concentrations in their bodies. Overweight or obese people usually have metabolic diseases or syndromes, Confounding which decelerate the elimination of DDT from blood and, thus, lead to high DDT concentrations in their bodies. Most participants in the not exposed group were patients with Stage III Reverse causality cancers who had undergone a severe pathological weight loss, whereas most participants in the high DDT exposure group were recruited from obesity and weight management clinics..

1. Q7) Based on the information above, the environmental epidemiologists concluded that human
exposure to DDT led to overweight or obesity of adults. However, this conclusion may be spurious
or ostensible because it could suffer various biases and errors, i.e., there exist other possible
explanations for the observed association between DDT exposure and obesity. Please link the
alternative mechanisms described below with the types of bias or error based on what you learned
in this course. People who eat more lipid-rich food are more likely to be overweight or Sampling
bias obese after 5 years, and because of the bioaccumulation of DDT in lipid, these people ingest
more DDT and have high DDT concentrations in their bodies. Overweight or obese people usually
have metabolic diseases or syndromes, Confounding which decelerate the elimination of DDT
from blood and, thus, lead to high DDT concentrations in their bodies. Most participants in the not
exposed group were patients with Stage III Reverse causality cancers who had undergone a
severe pathological weight loss, whereas most participants in the high DDT exposure group were
recruited from obesity and weight management clinics.