Some people are more vulnerable to contaminants in drinking water than the general population because their health is more fragile. This could be a result of a weakened immune system due to chemotherapy treatment, organ transplantation, HIV/AIDS or other serious disorders. Additionally, some elderly people and infants can be at risk from infection. People with these types of health challenges should get additional advice about drinking water from their health care providers.

Some constituents are known to especially affect people with weakened immune systems. This is the case with a microscopic parasite called, "Cryptosporidium" which can cause a life-threatening infection. Cryptosporidium is found in surface water (which comes from rivers, snowmelt and streams as opposed to ground water from wells) and some occasionally pass into the treated water supply. Although Cryptosporidium may be spread via drinking water, it is more commonly spread through poor hygiene or contaminated foods.

Metropolitan has monitored for Cryptosporidium since 1994 when the problems associated with the organism first gained widespread scientific and national attention. Metropolitan collects monthly samples of water both before and after treatment at each of five water treatment plants and monitors for Cryptosporidium. Metropolitan did not detect Cryptosporidium in any of the routine monitoring samples collected last year.

Guidelines from the EPA and the U.S. Centers for Disease Control and Prevention to lessen the risk of
infection by Cryptosporidium and other microbial contaminants are available by calling EPA's Safe
Drinking Water Hotline at (800) 426-4791or visiting their Web site .