Copper at very high levels is toxic and can cause vomiting, diarrhea, loss of strength or, for serious exposure, cirrhosis of the liver. Water turns blue-green in colour as the corroded copper comes off the inside of the pipes and appears in the water as a precipitate. This reaction only occurs in a small percentage of cases.
Lead is the most significant of all the heavy metals because it is both very toxic and very common. It gets into water from the corrosion of plumbing materials, where lead has been used freely since Roman times. In addition, lead can be found in the solder used to join copper pipes, and in fittings and faucets made from brass.
Bacteria this is for informational purposes not really an issue in San Diego due to the high chlorine and chloramine usage.
There are a wide variety of bacteria that can be found in drinking water, most of which pose no health hazard. Unfortunately, certain bacterium including certain strains of E.coli can cause terrible illness. Water quality reports often talk about fecal coliform contamination as a measure of bacteriological safety. While fecal coliform bacteria are for the most part harmless, their presence in drinking water is a warning sign that the water supply has been compromised and that other harmful bacteria like E.coli or other contaminants such as nitrites or pesticides may be present. Bacteria most often enters drinking water through sewage contamination or run-off from agricultural operations.
E. coli (Escherichia coli) is a type of fecal coliform bacteria commonly found in the intestines of animals and humans. There are numerous strains of E.coli, the majority of which are relatively harmless. However, E.coli strain 0157:H7 is one of the most serious drinking water contaminants, responsible for numerous North American deaths each year. The presence of E. coli in water is a strong indication of recent sewage or animal waste contamination. During rainfall, snow melt, or other types of precipitation, E. coli may be washed into creeks, rivers, streams, lakes, or groundwater. E. coli O157:H7 produces a powerful toxin which can result in severe diarrhea (often bloody) and abdominal cramps. Frequently, no fever will be present. Symptoms usually appear within 2 to 4 days, but can take up to 8 days to appear. Most people recover without antibiotics or other specific treatment in 5-10 days. There is no evidence that antibiotics improve the course of disease, and it is thought that treatment with some antibiotics may precipitate kidney complications. Antidiarrheal agents should also be avoided.
In some people, particularly children under 5 years of age and the elderly, the infection can also cause a complication known as hemolytic uremic syndrome, in which the red blood cells are destroyed and the kidneys fail. Roughly 2%-7% of infections lead to this complication. In the United States, hemolytic uremic syndrome is the principal cause of acute kidney failure in children, and most cases of hemolytic uremic syndrome are caused by E. coli O157:H7. Hemolytic uremic syndrome is a life-threatening condition requiring blood transfusions and kidney dialysis. With intensive care, the death rate for hemolytic uremic syndrome is 3%-5%.
The good news is that bacteria are effectively killed by ultraviolet (UV) water purification. Reverse osmosis and to a lesser degree, KDF filter media, are also affective in reducing bacteria in water, although they should not be relied upon solely if your water supply is known to be contaminated with bacteria.
Cysts this is for informational purposes not really an issue in San Diego due to the high chlorine and chloramine usage.
Cysts are small microorganisms generally consisting of a small number of living cells (often only one). While they are resistant to household UV purification, the preferred method of eliminating most waterborne microorganisms, their larger size makes it possible to remove them with fine filters including reverse osmosis and 0.5 micron carbon block filters. The two most frequently discussed waterborne cysts that cause disease in humans are Cryptosporidium and Giardia.
Cryptosporidium (crip-toe-spor-ID-ee-um) is a protozoan, a single-celled parasite, that lives in the intestines of animals and humans. This microscopic pathogen causes a disease called cryptosporidiosis (crip-toe-spor-id-ee-O-sis). The dormant (inactive) form of Cryptosporidium, called an oocyst (O-o-sist), is excreted in the feces (stool) of infected humans and animals. The most common symptom of cryptosporidiosis is watery diarrhea. It may also cause abdominal cramps, nausea, low-grade fever, dehydration, and weight loss. Symptoms usually develop 4 to 6 days after infection but may appear anytime from 2 to 10 days after infection.
People with healthy immune systems will usually feel ill for several days but rarely more than two weeks. Some infected individuals may not even get noticeably sick. Often, a patient will appear to be on the verge of recovery, only to get worse again. Cryptosporidiosis may cause complications for those with illnesses or conditions such as diabetes, alcoholism, or pregnancy. The effects of prolonged diarrhea and dehydration can be dangerous, especially for the very young, the elderly, and the frail. Correspondingly, Cryptosporidiosis is most severe and long-lasting in immunocompromised individuals (whose immune systems are weak), such as people infected with HIV or AIDS, cancer patients on chemotherapy, transplant patients, or others taking medications that suppress the immune system.
Despite drinking water standards, outbreaks of Cryptosporidiosis have become more common during the past 20 years, even in municipally-treated water systems. In 1987, some 13,000 people in Carrollton, Georgia became ill with cryptosporidiosis. This was the first report of the disease's spread through a municipal water system that met all state and federal drinking water standards. In the spring of 1993 in Milwaukee, Wisconsin, municipal drinking water, again within standards, was contaminated with Cryptosporidium. An estimated 400,000 people became ill and the disease contributed to the deaths of some AIDS patients.
Cryptosporidium cysts have tough walls that can withstand many environmental stresses and are resistant to the chemical disinfectants such as chlorine that are traditionally used in municipal drinking water systems.
Giardia lamblia (commonly referred to as Giardia) is a single-celled microbe or protozoa. When ingested, they can cause a gastrointestinal disease called giardiasis, often referred to as "Beaver Fever." Giardiasis is a frequent cause of diarrhea. Symptoms may include diarrhea, fatigue, and cramps. Waterborne giardiasis may occur as a result of disinfection problems or inadequate filtration procedures. Giardia cysts can infect humans and other animals.
While pesticides constitute a relatively small portion of the total synthetic organic compounds that contaminate our water supplies, the serious health consequences they cause warrant our attention.
Pesticide Contamination of Water
Two factors have influenced the increasing incidence of pesticide contamination being detected in our water supplies has resulted from two factors. First, is the increasing use of organic pesticides over the past 50 years. Between 1950 and 1980 production of synthetic organic pesticides more than tripled in the United States to over 1.4 billion pounds. To date, more than twenty types of pesticides have been detected in U.S. wells, and it is believed that nearly one hundred have the potential to invade our water systems based on their chemical characteristics. Areas with shallow water tables, sandy soils, and where agriculture is intensive are more prone to contamination. Some level of pesticide contamination has been detected in every state and province on the continent. Secondly, laboratory tests have become much more effective at detecting low levels of contamination.
The health effects of pesticides and the likelihood that they will enter our water systems depend upon their chemical characteristics.
Before the 1940s most pesticides were compounds of arsenic, mercury, copper, or lead. Although these compounds may have made their ways into drinking water, they were not highly soluble, and the residues ingested in foods were of far greater concern.
Synthetic organic pesticides were introduced during World War II and were mistakenly thought to be both safer and more effective. Pesticides in this group include chlorinated hydrocarbons such as DDT, aldrin, dieldrin, chlordane, heptachlor, lindane, endrin, and toxaphene. Because of their low solubility in water and their strong tendency to chemically attach to soil particles, these compounds have rarely contaminated groundwater, and are more frequently found to contaminate surface waterways. Use of most of the chlorinated hydrocarbon pesticides has been restricted or banned due to their toxic effects and concerns over their long-term accumulation in the environment. Organophosphorous compounds such as malathion and diazinon have begun to replace these compounds. Although some organophosphorous compounds are highly toxic to humans, they generally break down rapidly in the environment and therefore are less frequently found in groundwater. Another group or pesticides that have replaced chlorinated hydrocarbons are carbamate pesticides including aldicarb, carbofuran, and oxamyl. These compounds tend to be soluble in water and are only weakly adsorbed by soil. Consequently, if not degraded in the upper soil layers, they have a tendency to migrate into groundwater. While these more modern pesticides are found less frequently than chlorinated hydrocarbon pesticides in our groundwater, they can both be found in surface water sources where many municipalities and private water systems get their water supplies. Further, it is important to note that while chlorinated hydrocarbon based pesticides are regulated much more closely than they once were, they remain a threat since many decompose very slowly and may contaminate soils for very long periods. Chlordane, a highly persistent pesticide, was commonly used for termite treatments until it was banned in 1989. It can still be found in drinking water in many regions.
Studies of the health effects of pesticides on humans focus on two aspects, the acute toxicity or immediate effects resulting from short-term exposure, and the chronic toxicity or effects resulting from more-prolonged exposure. When pesticides are found in water supplies, they normally are not present in high enough concentrations to cause acute health effects such as chemical burns, nausea, or convulsions. Rather, they typically occur at trace levels, and the concern is primarily for their potential for causing chronic health problems such as organ failure (esp. liver, kidneys), nervous system disorders, birth defects, and/or cancer.
Pesticides by definition are toxic to at least some forms of life. The specific health effects of exposure depend upon concentrations, capacity to be absorbed by the body, how quickly compounds are metabolized and excreted from the body, and other factors. Drinking water guidelines are aimed at keeping pesticides at levels below those that are considered to cause any health effects in humans, however because the exact level at which exposure to a pesticide actually causes an adverse health affect is unknown, it is advisable to avoid pesticide exposure whenever possible, whether it being in your environment, food, or water.
Hydrogen sulfide has an offensive "rotten eggs" odor that is detectable at very low concentrations. In water, the taste and odour thresholds for hydrogen sulfide are estimated to be between 0.05 and 0.1 mg/liter.
Although considerably offensive in taste and smell, oral ingestion of hydrogen sulfide is not generally considered a health risk. It is unlikely that anyone could consume a harmful dose of hydrogen sulfide in drinking water, however, due to its offensive odor and taste, it is desirable to filter it from your drinking water if it is present.
Most of the hydrogen sulfide that occurs in drinking water is derived from natural sources and industrial processes. It is particularly noticeable in some groundwater, depending on source rock mineralogy and microorganisms present.
If your household water or well water is contaminated with iron and/or manganese, chances are you will know it. Rust colored stains on your fixtures and clothing, bad tasting and/or smelling water, and maybe even sludge growing in your toilet tank can all be signs that you have a problem with iron and/or manganese in one form or another. Regulatory bodies who deal with water issues classify iron and manganese as "secondary" contaminants - those that do not pose a direct health risk, but instead create problems due to unpleasant odors, tastes, and colors, etc.
Medications, including antibiotics and contraceptives, are increasingly a problem in the water supply due to improper disposal and other issues. Filtration helps remove these potentially dangerous chemicals.