May I know how old is your husband?
How extensive is his memory loss?
Does he has any other known medical illness?
Presence of any heavy metals in the body can be tested in laboratory. Aluminum levels can be tested in blood, urine, hair and fingernails, and feces. The hair test may provide hair levels that reflect past or chronic exposure to aluminum.
I hope the alteration of his memory is not age related. It could be due to Alzheimer's but it could also be due to any other causes.
Anyway just to let you know the close association of aluminum exposure to Alzheimer's disease. "Alzheimer's disease is related to the accumulation of a substance called "beta amyloid" in the brain. This is often seen in combination with exposure to aluminum or other toxic metals." For more information, visit this link: http://www.healthbeatnews.com/SlowDementiaAlzheimers.htm
Take care and good luck!