Final answer:
The organ most likely to be damaged by excessive alcohol consumption over time is the liver. This damage can lead to serious health consequences, including kidney dysfunction and high blood pressure.
Step-by-step explanation:
Excessive consumption of alcohol is most likely to damage the liver over a long period of time. The liver plays a crucial role in the excretory system by breaking down toxic substances such as alcohol. When the liver cannot function normally due to conditions like cirrhosis often caused by chronic alcohol abuse, it not only impairs its own function but also puts added strain on the kidneys. This can lead to kidney dysfunction or even kidney failure. Chronic alcohol consumption can also lead to serious health issues, including high blood pressure, which is a risk factor for kidney disorders. Therefore, limit your alcohol intake to help preserve the health of your excretory system, which includes both the liver and kidneys.