Chlorine and You (Part 1)
Mention the word “CHLORINE” and the following images appear in your mind: the commonly used household bleach, swimming pools, table salt and, yes, the drinking water from the faucet.
Chlorine, whether you realize it or not, is around us and can be found in various forms. George Porter, Nobel laureate in chemistry, said: “So it comes about that salt, sodium chloride, formed from these violently reactive and poisonous elements, is not only safe, it is essential to life. And the element chlorine, seeking another electron wherever it can be found … is a destroyer of life and a useful [bacterium].”
KNOWING CHLORINE
Chlorine is element 17 on the famous Mendeleev’s Periodic Table of Elements and exists as a chloride ion (CI) and as chlorine (Cl). Chlorine is in Group VII on the periodic table and classified as a halogen because it is highly reactive, and therefore, cannot exist as monatomic molecule. Chloride and chlorine are not produced the same way and do not have the same effects on the human body.
Chloride is found in the form of salts such as sodium chloride (NaCI) and potassium chloride (KCl). It maintains the electrical balance in the nervous system and is involved in intracellular and extracellular transport. Chlorine, on the other hand, exists only in the form of a diatomic molecule.
The blood contains 0.25% chlorine, 0.22% sodium, and 0.02 to 0.22% potassium. Hence, the chlorine content is higher than that of any other mineral in the blood.
HISTORY
Carl Wilhelm Scheele, a Swedish chemist, discovered chlorine in 1774 by treating hydrochloric acid with magnesium dioxide.
He called it dephlogisticated marine acid and mistakenly thought it contained oxygen. He isolated chlorine by reacting MnO, with HCl.
4 HCI + Mn02 — MnC12 + 2 H,O + C12
He observed several of the properties of chlorine. He noticed its bleaching effect on litmus, deadly effect on insects, yellow green color, and its smell which is similar to aqua regia. Then in 1810, Sir Humphy Davy insisted that it was an element and named it “chlorine,” who insisted that it was in fact an element.
Chlorine gas, also known as bertholite, was first used as a weapon in World War I by Germany. As described by the soldiers it had a distinctive smell of a mixture between pepper and pineapple. It also tasted metallic and stung the back of the throat and chest.
Chlorine can react with water in the mucosa of the lungs to form hydrochloric acid, an irritant which can be lethal. The damage done by chlorine gas can be prevented by a gas mask which makes the deaths by chlorine gas much lower then those of other chemical weapons. It was pioneered by a German scientist who later became a Nobel laureate, Fritz Haber of the Kaiser Wilhelm Institute in Berlin, and German chemical conglomerate IG Farben, who developed methods for discharging chlorine gas against an entrenched enemy.
It is alleged that Haber’s role in the use of chlorine as a deadly weapon drove his wife, Clara Immerwahr, to suicide. After its first use, chlorine was utilized by both sides as a chemical weapon, but it was soon replaced by the more deadly gases like phosgene and mustard gas.
IRAQ WAR
Chlorine gas has also been used by insurgents in the Iraq War as a chemical weapon to terrorize the local population and coalition forces. On March 17, 2007, for example, three chlorine-filled trucks were detonated in the Anbar province, killing 2 and sickening over 350. Other chlorine bomb attacks resulted in higher death tolls, with more than 30 deaths on two separate occasions. Most of the deaths were caused by the force of the explosions rather than the effects of chlorine, since the toxic gas is readily dispersed and diluted in the atmosphere by the blast. The Iraqi authorities have tightened up security for chlorine, which is essential for providing safe drinking water for the population.
BENEFITS
Usually combined with other chemicals, chlorine is used to disinfect water, purify metals, bleach wood pulp and make other chemicals.
Household bleach, used to whiten fabrics or remove mold from surfaces, is a 5% solution of a stabilized form of chlorine. Do not mix it with acid-containing or ammonia-containing cleaners. Dangerous levels of a very harmful gas can be released.
ECOLOGICAL HAZARDS
Most of the chlorine that enters lakes, streams, or soil evaporates into the air or combines with other chemicals into more stable compounds. Chlorine-containing chemicals that seep through soil down into groundwater can remain unchanged for many years.
CHLORINE EXPOSURES
How are people exposed to chlorine?
Exposures to chlorine gas, according to Wisconsin Department of Health and Family Services, are usually due to industrial processes or accidental spills. Chlorine is added in small amounts to some municipal water supplies when bacterial contamination threatens public health. When chlorine combines with lake or river water, a class of chemical that includes chloroform can be formed.
Breathing. Most high-level exposure occurs in workplaces where chlorine is used. People may inhale chlorine by using chlorine bleach or by living near an industry that uses chlorine. The smell from treated drinking water or swimming pools may be irritating but it is not harmful.
Drinking and Eating. Low-level exposure can occur when water containing chlorine is used for drinking or food preparation.
Touching. The body does not absorb chlorine well. However, small amounts can pass through the skin when people are exposed to chlorine gas, chlorine bleach, or bathing in water with high levels of chlorine. Lower levels of exposure can occur when people handle soil or water containing chlorine.
Do STANDARDS EXIST FOR REGULATING CHLORINE?
The Metro Manila Drinking Water Quality Monitoring Committee (MMDWQMC) is mandated to monitor the quality of water being served by the two concessionaires.
During its meeting on June 17,2003, MMDWQMC reported that the sampling points in Maynilad and Manila Water distribution systems had satisfactorily complied with the bacteriological requirement of the Philippine National Standards for Drinking Water (PNSDW).
The average residual chlorine is 0.70 parts per million (ppm) for the East Service Area and 0.93 ppm for the West Service Area. The PNSDW requires at least 0.2 ppm residual chlorine from the farthest point of the distribution system.
Moreover, physical and chemical characteristics such as pH, color, taste, odor, turbidity, chlorine, iron, hardness, total dissolved solids, sulfate, fluoride, calcium and magnesium were analyzed and found to comply with the PNSDW requirements.
Based on the above findings, the Committee pronounced that the drinking water in the MWSS distribution system was of Sanitary Quality with adequate residual chlorine.
HARMFUL HEALTH EFFECTS
Will exposure to chlorine result in harmful health effects? The answer is definitely yes.
Based on the studies conducted by the U.S. Department of Health and Human Services, National Cancer Institute, Food and Drug Administration and the Environmental Protection Agency, the harmful effects of chlorine exposure to human health are as follows:
Short-term, high level exposures
Immediately or shortly after exposure to 30 ppm or more of chlorine gas, a person may have chest pain, vomiting, coughing, difficulty breathing, or excess fluid in their lungs. Exposure to 430 ppm in air for 30 minutes will cause death.
The health effects of breathing air that has less than 30 ppm of chlorine are the same as listed below for inhaling liquid bleach vapors.
Liquid chlorine bleach and its vapors (at levels of 3-6 ppm in air) are irritating to eyes. At levels of 15 ppm in air, people experience nose and throat irritation. Touching liquid chlorine bleach can cause skin irritation. Drinking levels over 4 ppm can cause throat and stomach irritation, nausea and vomiting.
Long-term, low level exposure
The following health effects can occur after several years of exposure to chlorine:
Lung Disease and Tooth Corrosion. The main effects of exposure tq chlorine gas include diseases of the lung and tooth corrosion. People with previous lung disease, smokers, and those with breathing problems are more sensitive to chlorine.
Cancer. The American Journal of Health states that chlorine is linked to an increase in certain types of cancer, asthmas, and skin irritations. In a 1987 study by the National Cancer Institute, the FDA and EPA found an increased risk of bladder cancer with long term consumption of chlorinated water. The EPA says that chlorine follows cigarette smoke in leading causes of cancer. An experiment done on chickens by adding chlorine to their water caused 95% of them to develop atherosclerosis.
Two-thirds of the harmful chlorine exposure actually comes from showering. A 15-minute hot steamy shower is equivalent to drinking 8 glasses of water because of the vapors inhaled. The EPA states that “Due to chlorine and showering virtually every home in America has a detectable level of chloroform in the air.” This is because chlorine vaporizes in steam and combines with other organic compounds into chloroform which is a strong respiratory irritant and causes fatigue. A warm shower opens pores and allows a high rate of absorption. During a shower, 98% of the water goes down the drain, while 70%-90% of the chemicals vaporize before the water hits the ground and the vapors remain in the air.
Due to chlorine and the combination of many chemicals used in household cleaning, the average indoor air is five times more toxic than outdoor air regardless of whether the home is in the city or a rural area. Cancer has been shown to grow twice as fast indoors than outdoors. Bathing in chlorinated water also strips the natural protective oils in the skin and hair causing scaling and itching. It is also a major irritant for skin conditions like eczema and psoriasis. It kills the beneficial bacteria on the surface of the skin that offer a natural defense against skin disorders.
Effects in Reproduction. Evidence has been emerging of the impacts of chlorine chemistry on our health and on the environment. While many substances have been investigated for their ability to cause cancer and other acute and chronic conditions, recent studies have indicated a far more subtle and extremely worrying suite of effects on health.
Many chlorinated compounds are being linked to hormone disruption in both adults and in the developing fetus. Hormones are the body’s chemical messengers, and are responsible for switching on and off essential bodily functions and reactions. For example, the reproductive system in women operates on a monthly cycle that is regulated by hormones. Many chlorinated compounds are known to be hormone disrupters, in that they can mimic or block the action of the body’s own hormones.
Contamination of the food chain with these chemicals has led to human and wildlife populations with body burdens of toxic chemicals that they are unable to break down and eliminate. These chemicals are increasingly being linked to trends such as reduced sperm counts in men.
Perhaps the most worrying effect of all, however, is the potential of these chemicals to affect development of the fetus. Laboratory studies have shown that exposure to extremely low concentrations of hormone-disrupting chemicals during a very short critical period can have permanent detrimental effects on the fetus, and can affect both physical and intellectual development.
PVC (polyvinyl chloride) plastic is a source of two potent hormone-disrupting substances: dioxins and phthalates. Dioxins are a class of unintentional industrial byproducts created during the PVC manufacturing process, and during the combustion of PVC in waste incinerators and accidental fires. One of the dioxins, 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin, is the most toxic substance yet identified. Phthalates are a class of non-chlorinated compounds that are almost exclusively used as plasticizers added to PVC to make it soft and flexible for applications such as cable sheathing and children’s toys.
MEDICAL TEST NEEDED
By testing lung function and examining your skin and teeth, your doctor can evaluate the health effects of chlorine exposure.
Seek medical advice if you have any symptoms that you think may be related to chemical exposure.
