Is there any danger of illness from drinking tap water? And should one drink bottled water instead? In considering the safety of tap water, one needs to start with understanding what water treatment is all about.
To start with, all water - be it surface water, well water or rain water - has impurities. These impurities, if ingested in large enough quantities, can be dangerous to one's health. Because of this, governments around the world make it part of their business to regulate the quality of drinking water and to certify it as safe.
Fresh water, under natural conditions, usually contains microorganisms. This includes bacteria, bacterial spores, parasites, parasite eggs and/or larvae, protozoan, amoebas and other microorganisms. Most of these are killed off in the digestive tract or destroyed by the immune system and are harmless. However, some can cause vomiting and diarrhea, while others may cause more serious illnesses.
Naturally available fresh water always contains trace amounts of heavy metals that can include cadmium, chromium, cobalt, copper, iron, manganese, molybdenum, lead, mercury, plutonium, tungsten, vanadium and zinc. In addition, water contains dissolved gases such as ammonia, carbon monoxide, iodine, methane, nitrous oxide and nitrates to name a few. While municipal water is generally safe, concerns about the body's tolerance to these agents arise when we consider the overall health of the consumer.
Along with these naturally occurring chemical agents, fresh water supplies in developed areas of the Earth also contain pharmaceuticals, including over-the-counter medications, antibiotics and psychopharmacology drugs used for managing mental disorders (e.g. Prozac and Zoloft) that are eliminated from the body after ingestion. These are found in trace amounts and do not, according to public health authorities, generally pose a threat to humans in the present. But researchers are discovering that the trace amounts can be harmful to other natural organisms, and there is concern about continued increases in the concentration of agents.
Fresh water in developed areas also contains anthropogenic synthetic agents. This includes agricultural chemicals like pesticides, herbicides and fertilizers as well as industrial agents, such as petrochemical by-products, chlorofluorocarbons (CFC), phencyclidine (PCP) and other industrial chemicals.
Public health officials have not found these agents to pose a serious risk to the general public. However, environmental researchers have found that these chemicals can be very toxic to different species, and the potential for chemical cocktail-like combinations of these agents is so numerous that it's impossible to test them all.
Nature is able to clean many of these impurities out of the water. It occurs by (1) aeration as water evaporates from the surface, (2) photochemical reactions, as the water in clouds is exposed to sunlight and atmospheric gases, (3) filtering through sand, gravel and soil and (4) sedimentation as the water rests in oceans and lakes before evaporating. Unfortunately, not all freshwater is purified enough for humans to consume it safely.
To remove these impurities, water is treated in several steps. These are (1) coagulation, a step in the process that uses chemical additives to bond with small dirt particulates; (2) sedimentation, the step that removes the floating particulates; (3) filtration, when water passes through layers of sand, gravel and charcoal to remove the smallest particles; (4) disinfection, the infusion of chemicals (usually chlorine) to kill any possible remaining microbial agents; and (5) storage, the final process that gives the disinfection agents time to work before the water is dispensed to the public. This five-step process, while generally effective in providing safe water, is not perfect. It might be enlightening to check out the water quality of your own tap water.
Are There Psychoactive Drugs in Your Drinking Water?
Americans ingest more that 200 million prescription drugs like antidepressants every year. Between women seeing gynecologists and their children seeing obstetricians, over 210 million antibiotics were prescribed. Internists generate nearly 1.5 million antibiotic prescriptions per week. In the UK, the number of antidepressant prescriptions is 24 million. Add to this the use of medicines for family pets and in agriculture, and the amount of pharmaceuticals used in the US and UK runs into the hundreds of thousands of tons. What happens to these pharmaceuticals once they've been ingested and have accomplished their task?
Once a medication is ingested, it is metabolized. That means it passes through the body, is digested and then distributed throughout the body. Like other nutrients, the body takes what it needs. Once a medication is used to address the disease or disorder, the byproducts are returned to the blood stream. They are cleaned from the blood by the liver and the kidneys and then eliminated from the body as waste.
The waste goes into the municipal sewage system where it is processed by sedimentation techniques (settling) and chemical sanitation. The sediment is removed and placed in landfills or used as a solid soil fertilizer. The water is either processed and reused or returned to the environment for natural recycling. It sounds easy enough.
However, the vast majority of pharmaceuticals are not substances found in nature. They are synthetics, made from natural extractions, which have been altered for medical purposes. These alterations are intended to enhance the medicinal effect of the original extract by making it more metabolically friendly. While it may work well as medicines, its ambient presence in the soil, lake sediments and water systems poses a potential problem.
Once in the environment, microbes act as filters and build concentrations of the medications in their systems. Billions of these microorganisms are consumed and passed up the food chain until they are consumed by fish, crustaceans or mollusks. At this stage, the concentrations of pharmaceuticals can become problematic. In metropolitan areas where sewage released in water is especially high, fish can become disoriented by medical contaminants. Shrimp are known to change their behavior, making themselves more vulnerable to predators. Beyond their own behaviors, these organisms enter the food chain for larger, higher animals, including humans.
As ambient chemicals enter the water and soil, nature must make adaptations. Infectious bacteria can develop tolerances for antibiotics. Plants absorb the chemicals into their roots, stems and leaves. In higher order animals, diluted stimulants in the foods are stored in fat cells. When fat is burned by the body for nutrition, these chemicals are released as toxins. The effect can be disruption of the neuro-pathways, hormone sequencing and the reproductive cycles. While these symptoms are not seen widely in the world, the increasing use of pharmaceuticals and the ever more complex nature of their composition, without safeguards against environmental contamination, could well be a problem in the near future. The erratic behavior of fish, crustaceans and mollusks may well be the first warning signs.