- Water pollution caused by detergents has become a big concern in the global context.
- The per capita (per person) detergent consumption in India is around 2.7 kilogram per year.
- It is around 3.7 kg in the Philippines and Malaysia and 10 kg in the United States of America.
- Water pollution occurs when harmful substances—often chemicals or microorganisms—contaminate a stream, river, lake, ocean, aquifer, or other body of water, degrading water quality and rendering it toxic to humans or the environment.
- Water is uniquely vulnerable to pollution. Known as a “universal solvent,” water is able to dissolve more substances than any other liquid on earth.
- Some of the causes for water pollution are sewage water, industrial Wastes, agricultural sources, thermal and radiation pollution, marine pollution, invasive species, underground water pollution etc.
- A detergent is a surfactant or mixture of surfactants that has cleaning properties in dilute solution with water. A detergent is similar to soap.
- Surfactant, also called surface-active agent, substance such as a detergent that, when added to a liquid, reduces its surface tension, thereby increasing its spreading and wetting properties.
- Surface Tension is the property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of its molecules.
- They tend to be more soluble in hard water than soap because the sulfonate of detergent doesn’t bind calcium and other ions in hard water as easily as the carboxylate in soap does.
Detergents & Pollution:
- Nonylphenol, a hazardous chemical present in detergents, is known to enter water bodies and the food chains. It bio-accumulates and can pose serious environmental and health risks.
- It has been detected in human breast milk, blood and urine, and is associated with reproductive and developmental effects in rodents.
- Many laundry detergents contain approximately 35 to 75% phosphate salts. Phosphates can cause a variety of water pollution problems.
- For example, phosphate tends to inhibit the biodegradation of organic substances. Non-biodegradable substances cannot be eliminated by public or private wastewater treatment.
- Biodegradation is the process by which organic substances are broken down into smaller compounds by living microbial organisms.
- Some phosphate-based detergents can also cause eutrophication. Phosphate-enrichment can cause the water body to become choked with algae and other plants.
- Eutrophication: When a water body becomes overly enriched with minerals and nutrients which induce excessive growth of algae or algal bloom. It deprives the water of available oxygen, causing the death of other organisms.
- In Belgium, phosphates have been restricted for use in household detergents since 2003.
Bioaccumulation vs Biomagnification
- Bioaccumulation is when the concentration of chemicals increases within an organism or species. This can occur when toxic substances are ingested. These toxic substances are very difficult for organisms to excrete, therefore, accumulate in their tissues.
- Biomagnification is the process by which toxic chemicals build up within predators. This typically occurs across an entire food chain and affects all of the organisms but animals higher up in the chain are more impacted.
SOURCE: THE HINDU,THE ECONOMIC TIMES,MINT