Final answer:
Binge drinking can lead to dangerous behaviour and poses immediate risks to health and safety, which is the most critical issue concerning Edgar's alcohol use; his family history also increases his risk for alcohol dependency.
Step-by-step explanation:
The most critical issue concerning Edgar's drinking of alcohol is that binge drinking can lead to inappropriate and dangerous behaviour. This includes impaired judgement and coordination, which drastically increase the risk of accidents and injuries. Excessive alcohol consumption also has long-term health effects, such as damage to the liver and kidneys. Furthermore, given Edgar's family history of heavy drinking, he is at higher risk of developing a dependency on alcohol, which is known as alcoholism. Alcoholism is often considered a disease with a genetic predisposition, meaning individuals like Edgar may be more susceptible due to their genetic makeup and familial influences on behaviour.