Health and Environmental Effect of Uncontrolled Use of Chemical Based Detergent

More awareness on the control use of chemicals (such as detergents) that pollutes the environment and affects human is of great concern in the global context. Many laundry detergents contain approximately 35% to 75% phosphate salts. Phosphates cause a variety of water pollution problems. For example, phosphate tends to inhibit the biodegradation of organic substances. Non-biodegradable substances are not easily eliminated by public or private wastewater treatment. In addition, some phosphate-based detergents cause eutrophication. Over-enrichment of phosphate can cause the water body to become choked with algae and other plants. Eutrophication on the other hand deprives the water of available oxygen, causing the death of other organisms. Skins of human are affected in the use of the detergents and cancers arose when excessively ingested.

INTRO

Detergents figure in an extensive array of industrial and home cleaning applications, including laundry and dishwasher detergents. Released into the flow of wastewater coming from the home, these detergents can have far-reaching environmental impacts.

Although, detergents are obviously vital in the cleaning of the soiled oily rags and other domestic and industrial materials when they are dirty, as cleanliness is part of environmental friendliness. They are essential products that safeguard our health. Detergents are indispensable products for the maintenance of cleanliness, health and hygiene. But there is the need to look at how sustainable these detergents are to the environment and to man as they seem to do more harm than good.

Detergents unlike soaps that are made from natural substances are synthetic and are made of chemicals. Detergents came into brim light during world war due to the need for more soaps and better things that will clean the materials. This led to invent of the use of chemicals as against the natural agents used in soap making.

Aquatic organisms are in continuous danger and stand a chance of extinction due to the chemical deposits of some non-biodegradable chemicals that are major components/ingredients of detergents released into the water ways. The soil is also polluted with the reagents destroying the vital microorganisms needed in the soil as well increasing partly the activities of phytoplankton and other water algae/hyacinth, thus hindering the survival of zooplankton - in balance in the ecosystem.

These detergents have also caused lots of damage to the skin and eyes and caused lots of allergies to the external body while a high level contamination of the ingested ones causes cancer.

Alternative measures need to be applied to save our life and the environment from this silent but effective danger that are experienced from the use of detergent.

CONCEPT

Detergents are cleaning products manufactured from synthetic chemical compounds, as opposed to soap, which originates with natural substances like lye and plant saponins. Detergents are Sulfactants (compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid. Sulfactants may act as detergents and wetting agents, emulsifiers, foaming agents, and dispersants) or a mixture of surfactants with "cleaning properties in dilute solutions." These substances are usually alkylbenzenesulfonates, a family of compounds that are similar to soap but are more soluble in hard water, because the polar sulfonate (of detergents) is less likely than the polar carboxyl (of soap) to bind to calcium and other ions found in hard water. In most household contexts, the term detergent by itself refers specifically to laundry detergent or dish detergent, as opposed to hand soap or other types of cleaning agents. Detergents are commonly available as powders or concentrated solutions. Detergents, like soaps, work because they are amphiphilic: partly hydrophilic (polar) and partly hydrophonic (non-polar). Their dual nature facilitates the mixture of hydrophobic compounds (like oil and grease) with water. Because air is not hydrophilic, detergents are also foaming agents to varying degrees.

DETERGENT TYPES

Biological Detergent - Biological detergents are laundry detergents that contains enzymes harvested from micro-organisms such as bacteria adapted to live in hot springs. The description is commonly used in the United Kingdom, where other washing detergents are described as "non-biological" (or bio and "non-bio"). Most manufacturers of biological detergents also produce non-biological ones.

Biological detergents clean in the same way as non-biological ones with additional effects from the enzymes, whose purpose is to break down protein, starches and fat in dirt and stains on clothing to be laundered, for example food stains, sweat and mud. It is found that the performance of various makes of biological powders ranged from 58% to 81%, and non-biological powders scored from 41% to 70%. The enzymes in biological detergents enable effective cleaning at lower temperatures than required by normal detergents, but are denatured at higher temperatures—about 50°C is recommended. A biological detergent can contain amylase, cellulose, protease, and lipase.

Laundry Detergent - Laundry detergent, or washing powder, as otherwise called, is a type of detergent (cleaning agent) that is added for cleaning laundry. In common usage, "detergent" refers to mixtures of chemical compounds including alkylbenzenesulfonates, which are similar to soap but are less affected by hard water. In most household contexts, the term detergent refers to laundry detergent or other types of cleaning agents. Most detergent is delivered in powdered form.

DETERGENTS AS CHEMICALLY CLASSIFIED

Detergents are classified into Three (3) broad categories, depending on the sulfactants’ electrical charge. They are:

§  Anionic,

§  Cationic, and

§  Non-ionic and Zwitterionic detergents

Anionic Detergents - Typical anionic detergents are Alkyl benzene sulfonate. The alkyl benzene portion of these anions is lipophilic and the sulfonate is hydrophilic. Two different varieties have been popularized, those with branched alkyl groups and those with linear alkyl groups. The former were largely phased out in economically advanced societies because they are poorly biodegradable. An estimated 6 billion kilograms of anionic detergents are produced annually for domestic markets.

Bile acids, such as deoxycholic acid (DOC), are anionic detergents produced by the liver to aid in digestion and absorption of fats and oils.                  

Cationic Detergents - Cationic detergents are similar to the anionic ones, with a hydrophobic component, but, instead of the anionic sulfonate group, the cationic sulfactants have quaternary ammonium as the polar end. The ammonium center is positively charged.

Quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure NR⁺, R being an alkyl group or an aryl group.

Non-ionic and Zwitterionic detergents - Non-ionic detergents are characterized by their uncharged, hydrophilic head groups. Typical non-ionic detergents are based on polyoxyethylene or a glycoside. Common examples of the former include Tween, Triton, and the Brij series. These materials are also known as ethoxylates or PEGylates. Glycosides have a sugar as their uncharged hydrophilic headgroup. Examples include octyl-thioglucoside and maltoside. HEGA and MEGA series detergents are similar, possessing a sugar alcohol as headgroup.

Zwitterionic detergents possess a net zero charge arising from the presence of equal numbers of +1 and −1 charged chemical groups. Examples include CHAPS.

DETERGENTS COMPOSITION AND FUNCTION

Laundry detergents are formulated from six groups of substances which are discussed with their functions as:

Sulfactants – are organic chemicals, obtained through complex chemical reactions, from oil or  fat raw materials. They have wetting, emulsifying and dispersing properties, enabling the removal of dirt ("soil") from fabrics and keeping the soil suspended in the washing water.

Detergents usually contain several types of surfactants such as soaps (anionic), alkylbenzenesulphonate (anionic), ethoxylated fatty alcohols (non-ionic). The mixture is carefully balanced to control foaming and provide the appropriate washing efficiency (for the required washing temperatures, types of fabric and water hardness); at a price the consumer is willing to pay.

However, surfactant efficiency is very much reduced in hard water and their detergent properties are not complete even in soft water.

Builders – builders are key detergent components which remove the calcium and magnesium ions presents in hard water and in soils, thus lowering the concentration of surfactants necessary to perform the detersive action. Some builders also prevent the deposition of calcium and magnesium salts on fabrics and washing machines.

Sodium tripolyphosphate (STPP) is the most widely used builder and, in conjunction with surfactants, allows modern detergents to perform efficiently in all washing conditions, allowing the use of other essential ingredients to be minimised.

STTP also plays a number of other roles in detergents including maintaining alkalinity during washing (assists the removal of fatty soils), protecting the washing machine against corrosion, helping to suspend dirt in the wash water and prevent it redisposing on fabrics.

Zeolite A (a sodium aluminium silicate) is a synthetic builder, used in phosphate-free detergents, necessarily in conjunction with other chemicals. In most modern P-free detergents, zeolite is used with PCAs (polycarboxylates), but other chemicals have also been used in some detergents, for example NTA (nitrile tri acetic acid), EDTA, sodium carbonate, citrate, etc .

Zeolite absorbs, by ion-exchange, some of the calcium (but not the magnesium) presents in hard waters and soils, but the rate at which it is able to absorb calcium ions is many times slower than for STPP. Neither does it perform the other roles played by STPP in detergents. It is thus significantly less efficient than STPP and its use without any other change in the detergent formula would result in generally poor detergency and a severe increase of deposits on fabrics.

Bleaching agents – bleaching agents eliminate stubborn stains and ensure hygiene by killing bacteria through a chemical oxidation performed by a peroxygen generator, usually sodium perborate. The latter is usually active only above 60°C and so, for lower washing temperatures, an activator is added : eg. tetra acetyl ethylene diamine (TAED).

Enzymes – in particular: proteases, lipases and amylases. Catalyse the degradation of some stains and thus facilitate their elimination.

Other components – used in small quantities to ensure specific wash enhancing properties essentially include:

·       Enzyme stabilising agents ;

·       Fluorescent whitening agents which enhance the whiteness of fabrics and prevent natural yellowing ;

·       Anti-redeposition agents : cellulose derivatives (such as

carboxymethylcellulose) which help repel dirt from fabrics ;

·       Anti foams such as silicone to control the level of foam so that the

washing machine can operate properly ;

·       Perfumes ;

·       Corrosion inhibitors, such as sodium silicate.

Fillers – enable the adjustment of the active matter in the detergent to the doses used. Filler products include sodium sulphate in powders, water and solvents in liquids.

STPP (phosphates) fulfil several important functions in detergents:

§  Counteract the effects of calcium and magnesium salts present in hard water and in soils, thus allowing surfactants to function correctly. Phosphates prevent these ions combining with surfactants and rendering these inactive. They also condense to increase the surface activity of surfactants. Phosphates thus enable the detergent to actually wash correctly.

§  Prevent the deposit of calcium and magnesium incrustations on fabrics and on the washing machine’s heating elements.

§  Stabilise alkalinity at the correct level throughout the washing process thus giving good soil removal and enabling the other components of the detergents to function effectively.

§  "Anti-redeposition" properties. Phosphates help break up large particles of dirt into smaller ones, which can be washed out, and they help prevent fine dirt particles from combining and thus keep them in suspension in the wash water. Phosphates also help emulsify oily materials. Deposits on fabrics trap dirt and provide a breeding ground for bacteria. In addition, they cause washed fabrics to become harsh, grey, and to wear out more quickly.

§  Help the efficient manufacture, storage and use of detergents by stabilising detergents' physical properties.

§  Facilitate dissolving of detergents. Phosphates are highly soluble, and so facilitate and accelerate the dissolution of the detergent in the wash water, ensuring optimal performance. This is particularly important in tablet formulations, where the tablets must remain hard to handle, but dissolve very rapidly on contact with the wash water in order to disperse the concentrated surfactants they contain.

§  Redissolve calcium and magnesium compounds present in the washing machine from previous washes, thus reactivating any remaining detergents and improving detergent performance.

No other single chemical offers all, or even most, of these different properties, so that P-free detergents systematically contain a number of “new” chemicals as well as necessitating a complete change and reinforcement of other elements of the formulation.

APPLICATION/USES OF DETERGENTS

Biological Reagent

Reagent grade detergents are employed for the isolation and purification of integral membrane proteins found in biological cells. Advancements in the purity and sophistication of detergents have facilitated structural and biophysical characterization of important membrane proteins such as ion channels, transporters, signaling receptors, and photosystem II.

Biological detergents are commonly used to disrupt the bipolar lipid membrane of cells in order to release and solubilize membrane-bound proteins. Some detergents can be used to solubilize recombinant proteins, while others are recommended for the stabilization, crystallization, or denaturation of proteins. Detergents can align at aqueous/non-aqueous interfaces, resulting in reduced surface tension, increased miscibility, and stabilization of emulsions. Additional detergent applications include:

·         Extraction of DNA and RNA

·         Solubilization of specimens for diagnostic applications

·         Cell lysis

·         Liposome preparation

·         Prevention of reagent and analyte precipitation from solution

·         Prevention of non-specific binding in immunoassays

Fuel additives

Both carburettors and fuel injector components of auto engines benefit from detergents in the fuels to prevent fouling (the accumulation of unwanted material on solid surfaces to the detriment of function). Concentrations are about 300 ppm. Typical detergents are long-chain amines and amides such as poly-isobutane amine and poly-isobutene amide/succinimide.

Laundry detergents

One of the largest applications of detergents is for cleaning clothing. The formulations are complex, reflecting the diverse demands of the application and the highly competitive consumer market. In general, laundry detergents contain water softeners, surfactants, bleach, enzymes, brighteners, fragrances, and many other agents as had earlier been mentioned above. The formulation is strongly affected by the temperature of the cleaning water and varies from country to country.

Soapless soaps

Soapless soaps refer to soap free liquid cleanser (detergents or cleansing creams, other than soap, for cleaning the skin, especially removing greasy films or glandular exudates. Soap substitutes can be made from a variety of sources including plants with high saponin levels. Soap substitutes should not be confused with natural cleaning products which are cleaning agents for kitchen and house use) with a slightly acidic pH.

  

FORMULATION OF PHOSPHATE – FREE DETERGENTS

After 30 years of research no adequate substitute for STPP has been found: that is, a single substance which can take its place in a detergent formula without requiring other undesirable additions to the formula and without decreasing, below an acceptable level, the level of cleanliness and hygiene achieved.

In fact, a phosphate-free formula is usually completely different from a phosphate-containing one, using several new chemicals along with a different balance of existing ones, with a series of changes being necessary to resolve the succession of problems which arise when STPP is not used. Phosphate-free formulations as a general rule contain some or all of the following chemicals:

§  Zeolite A as a principal builder, this is an artificial, insoluble compound based on aluminium and silicate

§  PCAs (polycarboxylates), non-biodegradeable long chain petrochemical molecules, used to reduce deposition of calcium and magnesium salts which result from the poor ion removal properties of zeolite A

§  Reinforced surfactant system : higher total surfactant load and/or modified proportions of different surfactants

§  Increased enzyme content

§  Perborate activators added or levels increased to improve bleaching.

§  Sodium carbonate to maintain alkalinity

§  Small amounts or increased levels of organo-phosphates and citrates

EFFECT OF DETERGENT

Detergents are known to have caused lots of negative impacts both on Health and Environment. The important components of detergents forming sulfactants, builder and etc have been identified to affect human and environment. Detergents effect could be broadly classified as:

Health Effect

Sulfactants a major component of detergent is known to cause rough skin surface, the loss of natural moisture on the surface of the skin and increase the permeability of the outer skin surface. The test results show that human skin is only able to tolerate contact with chemicals contained in the detergent with irritation due to 'being' on the skin. Cationic surfactants are toxic if ingested compared with anionic surfactants and non-ionic. The rest of the ingredients contained in the detergent surfactants can form klorinisasi chlorbenzene in drinking water treatment process taps. Chlorbenzene is a chemical compound that is toxic and harmful to health. At first the type of ABS surfactants are widely used by industrial detergents. But because it found evidence that the ABS has a high risk to the environment, this material has now been replaced with another material that is less harmful.

Besides damaging the natural environment, the perceived adverse effects of detergents are not separated from its customers. The impact can also cause disturbances in the environment on human health. When after we wash clothes, our hands feel dry skin, burning, blistering, cracking, peeling easy to cause itching and sometimes become allergic.

Studies have shown that detergents has the ability to dissolve some essential ingredients in the body ( carcinogens, such as 3.4 Benzonpyrene) causing water to have odour and bad taste in addition disrupting the health stability of consumers as it later causes cancer.

Detergent decomposition process will result in residual benzene when reacted with chlorine to form chlorobenzene compounds these are very dangerous. Contact of benzene and chlorine are very likely to occur in drinking water treatment, considering the use of chlorine (which it contains chlorine) as a germ killer on the chlorination process.

Environmental (Aquatic Life) Effect

Phosphate, one of the most widely used builders in detergent formation is important as it is known to soften water and it reduces water. Phosphate is usually found in general form as Sodium Tripoly Phosphate (STPP). Phosphate is ordinarily not toxic but excess of it in the aquatic body causes eutrophication (nutrient enrichment) such that there will be oxygen deficiency resulting from algal (phytoplankton) growth and water hyacinth in the excess of food bacteria, thus exhausting the oxygen content of the water till a time the aquatic life becomes endangered and shades off light as sunlight will not penetrate into the water. This if not controlled have tendency of disrupting the ecosystem as it (water hyacinth) has already been found to block or hinder the flow of water from the channels causing flood. STPP has been bound from use in some countries and alternatively uses Zeolite and Citrate as Builder in detergent.

Generally, inflow or discharge of detergents into the water medium and soils poses a high threat to the environment as most of them contain ABS (alkyl benzene sulphate) which is non-biodegradable (non-decomposable by microorganisms) and is known to be a very toxic pollutant that threatens man and other organisms that depend on water for survival.

High phosphate detergent such as tri-sodium phosphate (TSP) is toxic when mixed with water as it destroy external mucus layers that protect fishes from bacteria and parasites and also damages the gills of fishes, this leads to the death of fishes while the low concentration of TSP kills the egg of fishes as such hinders the breeding ability of aquatic organisms.

Detergent also had a big hand in lowering water quality. Organic chemicals such as pesticides and phenols will be easily absorbed by fish, with only 2ppm concentrations of detergents can be absorbed by fish twice the amount of other chemicals. Detergents have negative effects on water biota. Phosphates in detergents can trigger freshwater algae to release toxins and deplete oxygen in the water. When algae decompose, they use the available oxygen to sustain life.

The materials used in packaging the detergents itself are of low quality that cannot be recycled and are found to be responsible in blocking the water channel and causing flood and other environmental impact.

SUGGESTED WAYS OF MINIMISING THE EFFECT

The ability of various detergents to remove dirt on the cloth or other object, reducing the presence of germs and bacteria that cause infections and increase the service life of fabrics, carpets, household appliances and other home appliances, is no doubt the major benefits of the use of detergents, thus becoming an important part that cannot be separated from the life of modern society.

Since the use of detergents have shown impact to the environment through poisoning of water in the treatment plant and water quality degradation, a substitute reagent with better characteristics like enzymes used in biological detergents ought to be employed as they may be easily decomposed by the micro-organisms as such making it environmentally friendly.

It will be very ideal if proper guidance and orientation be given to the consumers of these detergents as some of the detergents are health hazards that affect the skin and can even be poisonous when ingested. Specifications and proper directives need to be made to enable end users know the exact quantity that should be used and when as well as how. If this measure is properly taken, it will reduce foaming and bubbles and as such will not reduce the oxygen content of the aquatic habitat and saving the life of organisms therein. Proper awareness of how to dispose the sachets used in the packaging should be done and mostly conspicuously indicated on the sachets to enable end users stop littering them and discontinue it from blocking the water channel as well as suffocation of aquatic organisms.

More awareness on the benefits and impact of the use of washing machines need to be carried out as well as educating users on the need to be proactive and study the nature of the active ingredients in detergents they intend to purchase or use. In the same vein, strong policy should be enacted to control the use of non-environmental and non-healthy chemicals in the production of detergents and also to ensure that they use reagents and chemicals that will be good to the health of users. A clear environmental friendly logo should be marked clearly with green on the pack.

For further reading and references:-

Arnold, T., and Linke, D., Phase separation in the isolation and purification of membrane proteins. BioTechniques, 43, 427-440 (2007).

Celentano A, Sesana F, Settimi L, et al. Accidental exposures to liquid detergent capsules [Abstract 300]. 2012 International Congress of the European Association of Poisons Centres and Clinical Toxicologists; May 25–June 1, 2012; London, UK. Clin Toxicol 2012;50:353.

Garavito, R.M. and Ferguson-Miller, S., Detergents as tools in membrane biochemistry. J. Biol. Chem., 276, 32403-32406 (2001).

Helenius, A., et al., Properties of Detergents. Methods Enzymol., 56, 734-749 (1979).

Hjelmeland, L.M., Solubilization of native membrane proteins. Methods Enzymol., 182, 253-264 (1990).

McKenzie L, Ahir N, Stolz U, Nelson NG. Household cleaning product-related injuries treated in US emergency departments in 1990–2006. Pediatrics 2010;126:509.

Neugebauer, J.M., Detergents: an overview. Methods Enzymol., 182, 239-253 (1990). 

Williams H, Moyns E, Bateman DN, Thomas SH, Thompson JP, Vale JA. Hazard of household cleaning products: a study undertaken by the UK National Poisons Information Service. Clin Toxicol 2012;50:770–5.