MY PRIVATE WELL HAS AN ODOR THAT RESEMBLES CHLOROFORM. WHAT IS THE CAUSE OF THIS?

It is always a wise decision to be vigilant concerning the odor and taste of your drinking water, whether from surface or groundwater. Should your well water ever have an odor or taste problem, it should come as no shock given the volume of possible causes of it. There are at least 700 pollutants found in the drinking water, but the EPA is required to set standards for only about sixty of them, and these standards are routinely violated without consequence. Out of the 250,000 violations, the states took just over 2,600 enforcement actions, while the EPA took about 600. Municipalities struggle with outdated technology. Over 70,000 different chemical compounds are now in use by industry, agriculture, and private citizens, with 5,000 new and unproven chemical compounds being added into the environment each year. That amounts to 18 billion pounds of new pollutants every year.

So what is chloroform? Chloroform is also known as trichloromethane, methane chloride, or methyltrichloride. It is a colorless liquid with a pleasant, non-irritating odor and slightly sweet taste. Most of the chloroform found in the environment comes from industry. It will only burn when it reaches very high temperatures. Chloroform was one of the first inhaled anesthetics to be used during surgery, but it is not used for anesthesia today. Nearly all the chloroform made in the United States today is used to make other chemicals, but some is sold or traded to other countries. We also import chloroform. Chloroform enters the environment from chemical companies, paper mills, waste water from sewage treatment plants, and drinking water that contains chlorine. Chloroform can enter the air directly from factories that make or use it, and by evaporating from water and soil that contain it. It can enter water and soil when waste water that contains chlorine is released into water or soil. It may enter water and soil from spills and by leaks from storage and waste sites. In addition to its industrial production and use, small amounts of chloroform are formed as an unwanted product during the process of adding chlorine to water. Chlorine is added to most drinking water and many waste waters to destroy bacteria. There are many ways for chloroform to enter the environment, so small amounts of it are likely to be found almost everywhere.

Chloroform evaporates very quickly when exposed to air. Chloroform also dissolves easily in water, but does not stick to the soil very well. This means that it can travel down through soil to ground water where it can enter a water supply. Chloroform lasts for a long time in both the air and in the ground water. Most chloroform in the air eventually breaks down, but this process is slow. The breakdown products in air include phosgene, which is more toxic than chloroform, and hydrogen chloride, which is also toxic. Some chloroform may break down in soil. Chloroform does not appear to build up in great amounts in plants and animals, but we find some small amounts of chloroform in foods. Exposure Pathways You are probably exposed to small amounts of chloroform by drinking water and beverages (such as soft drinks) made using water that contains it.

You can also get chloroform in your body by eating food, by breathing air, and by skin contact with water that contains it.

You can also get chloroform in your body by eating food, by breathing air, and by skin contact with water that contains it. You are most likely to be exposed to chloroform by drinking water and breathing indoor or outdoor air containing it. The amount of chloroform normally expected to be present in air ranges from 0.02 to 0.05 parts of chloroform per billion parts of air (ppb) and from 2 to 44 ppb in treated drinking water. However, in some places, chloroform concentrations may be higher than 44 ppb. It is estimated that the concentration of chloroform in surface water is 0.1 ppb, the concentration in untreated ground water is 0.1 ppb, and the amount in soil is 0.1 ppb. Even though these levels seem low, much higher levels have been recorded. As much as 610 ppb was found in air at a municipal landfill and up to 88 ppb was found in treated municipal drinking water.

Drinking water derived from well water near a hazardous waste site contained 1,900 ppb, and ground water taken near a hazardous waste site also contained 1,900 ppb. Surface water containing 394 ppb has been found, and more than 0.13 ppb has been found in soil at hazardous waste sites. Chloroform has been found in the air from all areas of the United States and nearly all of the public drinking water supplies. We do not know how many areas have surface water, ground water, or soil that contains chloroform. The average amount of chloroform that you might be exposed to on a typical day by breathing air in various places ranges from 2 to 5 micrograms per day (ug/day) in rural areas, 6 to 200 ug/day in cities, and 80 to 2,200 ug/day in areas near major sources of the chemical. The estimated amount of chloroform you probably are exposed to in drinking water ranges from 4 to 88 ug/day.

We cannot estimate the amounts that you may be exposed to by eating food and coming into contact with water that has chloroform in it. Swimming in swimming pools allows chloroform to be absorbed through a person's skin. People who work at or near chemical plants and factories that make or use chloroform can be exposed to higher than normal amounts of chloroform. Higher exposures might occur in workers at drinking water treatment plants, waste water treatment plants, and paper and pulp mills. People who operate waste-burning equipment may also be exposed to higher than normal levels. The National Institute for Occupational Safety and Health (NIOSH) estimated that 95,778 individuals in the United States have had the potential for occupational exposure to chloroform.

If you suspect your drinking water my have chloroform pollution, there are some actions you can take. Your local board of health can help you determine whether you are exposed to chloroform exceeding regulatory standards. There is generally a fee associated with laboratory analysis.. For additional technical information and a review of current research, contact EPA's Safe Drinking Water Hotline at (800) 426-4791, or see the Agency for Toxic Substances and Disease Registry's (ATSDR) Toxicological Profile for Chloroform. Information about obtaining this profile is available by calling ATSDR's 24-hour Toxicology Information Service at (404) 639-6000 or by leaving a message on (800) 447-1544. To order toxicological profiles contact the National Technical Information Service at (800) 553-6847 or (707) 487-4650. There may be a fee for the profile.