Final answer:
High levels of alcohol consumption are a significant risk factor for colorectal cancer, alongside other lifestyle choices and environmental risk factors.
Step-by-step explanation:
When discussing risk factors for colorectal cancer with a local community group, a nurse should mention high levels of alcohol consumption as a significant risk factor. This aligns with the data which indicates that environmental risk factors, including lifestyle choices such as smoking and consuming a diet high in animal fats and proteins, increase the risk of developing colorectal cancer. Other environmental factors that heighten cancer risks generally, such as exposure to radon or UV light, are also pertinent but may not be as directly related to colorectal cancer as high alcohol intake.