To Treat or Not To Treat Water?
That is the Question.

http://www.geocities.com/jormabio/archive/watertreatornot.html
THM’s; Trihalomethanes; Chlorination By-Products (CBP's)
1,2-dichloroethane, see link http://193.51.164.11/htdocs/monographs/Vol71/015-dichloretha.html

dichloromethane (side issue; solvent residue of decaffienated coffee)
chloroform(trichloromethane) CHCl3
bromoform CHBr3
bromodichloromethane CHCl2Br
dibromochloromethane CHClBr2

They are Cancer Group B carcinogens (shown to cause cancer in laboratory animals.

Trichloromethane (chloroform) is by far the most common in most water systems. Dibromochloromethane is the most serious cancer risk, (0.6 ug/l to cause a 10-6 cancer risk increase) followed in order by Bromoform (4 ug/l), and Chloroform (6 ug/l). Current regulations limit the concentration of these 4 chemicals added together (total trihalomethane or TTHM levels) to 100 ug/l.
Kenneth P. Cantor et.al. Dec 1987 JNCI [ found that people who drank 8 cups of chlorinated tap water for 40-59 years had a 40% greater risk of bladder cancer than those who drank less tap water or unchlorinated water. People who drank 8 cups of chlorinated tap water for 60 or more years had an 80% greater risk of bladder cancer]

[Q. What about levels of solvent residues in coffee - are there laws about this? Under EU law, dicloromethane residue levels in decaffeinated coffee must be under 2 parts per million. For ethyl acetate and carbon dioxide there are no legislative restrictions in most countries.]

One way to decrease THM's is to eliminate or reduce chlorination before the filters and to reduce precursors. There are more precursors present before filtration, so we want to reduce or eliminate the time chlorine is in contact with this water.

If some oxidation before filtration is required, an alternative disinfectant like potassium permanganate or peroxide could be considered. Note that this may not be an option if prechlorination is necessary to achieve required CT values.

The EPA has indicated that the best available technology for THM control at treatment plants is removal of precursors through "enhanced coagulation".

Enhanced coagulation refers to the process of optimizing the filtration process to maximize removal of precursors.

Removal is improved by decreasing pH (to levels as low as 4 or 5), increasing the feed rate of coagulants, and possibly using ferric coagulants instead of alum.

For point of use systems at homes, activated carbon filters are the most effective treatment. Reverse osmosis units will also eliminate trihalomethanes.


HAA CBP's; Haloacetic acids;


monobromoacetic acid
dibromoacetic acid
monochloroacetic acid
dichloroacetic acid
trichloroacetic acid

Bromates; Ozonation Disinfection By-Products (DBP's)
Ozonation, is expensive and in salty water can produce other carcinogens, bromates. Treatment with ozone causes few DBPs but does result in the production of bromate when used in water with high bromine concentrations. Bromate has been shown in studies by the EPA to cause mesotheliomas in rats and kidney tumors in both rats and mice. In addition, oral exposures to potassium bromate have been shown to cause renal cancer in rats.

Chloramination; and DBP's
Or some combine chlorine withammonia in a disinfection method called chloramination.
Chloramines are composed of three chemicals formed when chlorine and ammonia-nitrogen are combined in water. In high doses chloramines cause blood and liver damage in laboratory animals. Monochloramine is preferred because of its biocidal properties and minimal taste and odor. Monochloramine is created by controlling the chlorine-to-ammonia ratio to a value generally less than 5:1 by weight or 1:1 on a molar basis.

The Chloramines are:

monochloramine (NH2Cl)
dichloramine (NHCl2)
trichloramine, nitrogen trichloride (NCl3).

Chloramination DBP's Summary; definitely some toxins, carcinogens

Nitrification

Blue-green algal blooms, if water temps high
Chloramines also have been found to produce total trihalomethanes (TTHMs)

bromodichloromethane
chlorodibromomethane
bromoform
dihaloacetic acids poorly controlled under some conditions (HAAs).
dichloroacetic acid causes cancer in rodents
dissolved organic halogen poorly controlled under some conditions

Research results imply that many unreported DBPs are created by chloramines.
two-step microbial process, ammonia is converted to nitrite and then to nitrate. The intermediate stage-nitrite--depletes the chloramine residual and increases heterotrophic bacteria.

nitrite
nitrate (two-headed fish in hatcheries)
haloacetonitriles
mutagen X, (MX)

Impending Regulations

The EPA is considering extensive revisions to the regulations covering disinfection by-products (DBP's).
The limit for TTHM's would be lowered to 80 ug/l, and three additional categories of DBP's . This standard will replace the current standard of a maximum allowable annual average level of 100 parts per billion in December 2001 for large surface water public water systems. [Canada uses 100 ppb]. The standard will become effective for the first time in December 2003 for small surface water and all ground water systems.

An MCL for total haloacetic acids of 60 ug/l is expected. Potential nervous system and liver effects.

Chlorite is to be regulated with an MCL set at 1 mg/l (1 ppm). Excessive levels linked to hemolytic anemia.

Bromate, the other newly regulated DBP , is a concern only for systems using ozone. An MCL of 10 ug/l is expected. Excessive levels causes gastrointestinal, kidney, and hearing effects.

Data Gaps….I haven't had time to fill these. Busy with life.

Reproductive toxicity.

Robert Chapin, a reproductive toxicologist in the Laboratory of Toxicology, is responsible for studies on 10 compounds identified as high priorities by the EPA: the THMs bromodichloromethane and chlorodibromomethane; the HAAs bromochloroacetic acid, dibromochloroacetic acid, and tribromoacetic acid; the haloacetonitriles bromoacetonitrile and dibromoacetonitrile; hexachloropropanone (a member of a lesser class of DBPs called the haloketones); sodium bromate; and a mixture of mono-, di-, and trichloroacetic acids, mono- and dibromoacetic acids, and bromochloroacetic acid (all HAAs). Long-term rodent carcinogenicity studies are being developed for six compounds under Boorman and one compound (MX)

H2O Treatment LINKS

http://www.awwarf.com/research/apps/chloram.htm

http://ehpnet1.niehs.nih.gov/docs/2000/108-2/niehsnews.html

Terminology used in water management and treatment link.
http://wilkes.edu/~eqc/glossary.htm

Water Quality Table link
http://www.eastgr.org/ccrtable.htm

For a neat regulatory package check this link. We Pay $16.95 to see Canadian guidelines; Indonesia=FREE!
Water Purity Regulation in Indonesia; Transparancy



Pesticides in Drinking Water
Violations in the USA

http://www.epa.gov/OGWDW/wot/howsafe.html

Calculating Maximum Pesticide Levels in Drinking Water

EPA table of Maximum Concentrations of Organic Chemicals in Drinking Water

My Conclusion

I am leaning towards reverse osmosis or activated charcoal or untreated pure water from a known tested healthy source like rain or a mountain spring. These may not be fool-proof either. One has to know their water.

Some countries fluoridate their water purportedly to provide drinkers with better teeth. I would expect fluoride to behave like these other halogens, chlorine and bromine, and generate a similar class of carcinogens and related byproducts. The reader should search the literature if they are curious about this. I have heard that fluoridation in the USA causes 10,000 additional cancer deaths per year. I do not recall the reference. Over-dosing is very likely for diebetics who drink large volumes of water and they are at special risk if it is added to the water. Fluoride is present in a balanced diet so one has to wonder why the health authorities wouldn't rather simply promote a balanced diet rather than fluoridate the water.

To sort through the health effects puzzle mozaic as it develops, keep abreast of research at Entrez PubMed or Medline etc. online journals, and compare original research results with what EPA and NIH are saying and how they translate this into policy recommendations. Another journal with some interesting relavence is Ecotoxicology and Environmental Safety

One of the biggest concerns I have is that to escape the known toxics DBP's from chlorination, many communities are getting on the chloramine bandwagon despite the fact that the health effects and toxics BP's are poorly known.

Water policy should evolve towards removing undesirable substances rather than replacing them with toxics and perhaps we should regard water in a more sacred light like our distant ancestors did rather than regarding it as a good hiding place for our excrement and toxic wastes and pesticide residues. Sacred springs were places of worship to the ancient Celts and Norse. What was so wrong with Grannies old Rain Barrel anyway?

How exactly did we, and the millions of other species, survive hundreds of millions of years of evolution without chlorinating our drinking water?

One of my greatest joys is hiking in the mountains is stooping to drink from a spring gushing forth from the base of a scree slope. To know how terrible city water is, one only has to do this once. There is no greater gift that nature has to offer than clean water. It is the stuff of life itself. You see, our bodies are filters of all that passes through. We best be careful not to clog those pores with the crud of human neglect. Know your water, care for it and respect it, and don't forget the other creatures' needs as well.

Note: People on kidney dialysis are at special risk from chloramination and so are aquaculture activities. Chloramines must be removed from water used in kidney dialysis, and medical authorities and patients should be informed of the presence of chloramines and chloramines must be removed from water used by kidney patients. Infants are at risk because some of these substances have been found in mothers breast milk and this may represent a concentration and this should be determined. See my archive article milkcarcinogens.html.


© 2002 Jorma Jyrkkanen.