Q. Did the elimination of chlorine in the water supply cause the outbreak of cholera in Peru?

A. No. In 1991 an outbreak of chlorea in Peru, which spread to the whole of Latin America, killed tens of thousands of people. It has been alleged by the chlorine industry that this was caused by a reduction in the amount of chlorine in the water supply.

According to the United Nations Children and Environment Fund (UNICEF) and other relevant health agencies such as Oficina de Assessoria y Consultoria Ambiental (OCAC) which work directly with the Peruvian Health Ministry there was no change in the water chlorination policy of the Ministry of Health. In fact studies of the particular strain of cholera found that it is particularly resistance to chlorination. A lack of sanitation, sewage and drainage, was identified as the main cause of the outbreak. Greenpeace advocates safe disinfection, not no disinfection as industry implies.

Q. Isn't an individual more likely to be killed by pathogens in unsafe water than from cancer caused by organochlorines?

A. Scientific evidence suggests people who drink chlorinated water are more likely to contract rectal and bladder cancer than those who drink non-chlorinated water (Morris R D et al, 1992; Bull R J et al, 1990; Beresford S A, 1986). One of the organochlorines found in drinking water has been found to cause dose dependent effects including birth defects, failed pregnancies and death when given to pregnant rats (Blatchley E R III et al, 1991). In addition, some bacteria such as cryptosporidium and giardia are highly resistant to disinfection by chlorine, and lead to vomiting, diarrhea, fever, cramps or nausea.

Alternative methods of disinfecting water, such as filtration, ozonation and UV light can also protect against pathogens and mean that we shouldn't have to expose ourselves to these risks associated with chlorinated drinking water. The main obstacle to implementing these alternative methods is the need for a proper infrastructure, with no broken pipes, which can be a problem in developing countries. The primary goal should be preventing the contamination of water resources upstream.

REFERENCES:

Beresford, S.A. (1986) Health risks associated with organic micropollutants in drinking water. IN: Organic Carcinogens in Drinking Water, Ram et al. , Eds, John Wiley & Sons, 542pp

Blatchley, E.R.III & Isaac, R.A. (1991) Disinfection. Res. J. WPCF 63(4): 416-424.

Bull, R.J., Gerba, C. & Trussell, R.R. (1990) Evaluation of health risks associated with disinfection. Crit. Rev. Environ. Control 20(2): 77-113.

Morris RD, Audet AM, Aggelillo IF, Chalmers TC, Mosteller F. Chlorination, chlorination by-products, and cancer: a meta-analysis. Am J Public Health 82(7):955;963 (1992).