Chemical pollution is defined as the presence or increase in our environment of chemical pollutants that are not naturally present there or are found in amounts higher than their natural background values. Most of the chemicals that pollute the environment are man-made, resulted from the various activities in which toxic chemicals are used for various purposes.
Chemical intoxication is caused by exposure to chemical pollutants and can have immediate effects or delayed effects, which may appear after weeks or even months after the exposure occurred. Severe chemical intoxication may cause the death of the person that inhales an increased quantity of such substances.
Chemical compounds are organic or inorganic chemicals that are the main causes of chemical pollution. The most common chemical pollutants are those compounds used across large areas and which are persistent, meaning they do not easily degrade in nature. Examples are most pesticides, herbicides, insecticides used in agriculture and gardening, as well as chlorinated solvents used in many industrial processes and dry-cleaning activities.
Types of Chemical Pollutants
Based on their chemical structure, chemical contaminants can be classified into naturally-occurring and man-made categories. They can be organic or inorganic (organic compounds always contain carbon and carbon-hydrogen bonds, whereas most inorganic compounds do not contain carbon).
Organic Chemical Pollutants are produced by living organisms or are based on the matter formed by living organisms.
- Crude oil and petroleum refined products (gasoline, diesel fuel, kerosene, mineral spirit, motor oil, lubricating oil);
- Solvents (acetone, MEK, toluene, benzene, xylene) used in industry and household products;
- PAHs (polyaromatic hydrocarbons) are found in petroleum products, crude oil, and as a result of burning activities in coal power plants, historical manufacturing gas plants, etc.;
- PCBs (polychlorinated biphenyl ethers), which are now banned, but were commonly used in transformers, so they are already present in large amounts in environment;
- Alcohols are used in a large variety of applications and household products;
- Trihalomethanes (chloroform, dibromochlorofrom, bromoform) which are common products of water chlorination;
- Phenols are usually an indication of waste water and a result of industrial processes;
- Plastics like bags, bottles, and containers are a result of industrial processes;
- Pesticides / Insecticides / Herbicides are commonly used in agriculture and may contain toxic organic chemicals and metals (such as mercury and arsenic);
- Detergents (e.g., nonylphenol ethoxylate) include a variety of chemical compounds with surface activities.
Inorganic Chemical Pollutants are those chemicals of mineral origin that are not produced by living organisms.
- Metals and their salts – usually resulted from mining activities and disposal of mining waste;
- Inorganic fertilizers (nitrates, phosphates) used in agriculture and gardening; when present in large amounts in water, they can be harmful to humans and algae;
- Sulfides (pyrite) are used in mining and can generate sulfuric acid if combined with rainwater and microorganisms;
- Ammonia is a poisonous gas that in higher amounts and can cause blindness followed by death;
- Acids and bases are used in some industrial applications and in chemical laboratories. If spread in large amounts, they pose a serious threat to the environment;
- Perchlorate is used in rocket fuels, explosives, military operations, fireworks, road flares, inflation bags, etc. Perchlorate is problematic because it is a persistent gas that can damage thyroid functions in humans.
Examples of Chemical Pollutants
Chemical pollutants mostly result from various human activities like the manufacturing, handling, storing, and disposing of chemicals. These occur in industrial places and activities such as oil refineries, coal power plants, construction, mining & smelting, transportation, agricultural use of pesticides and insecticides, as well as household activities.
The chemical industry is another example in this sense, mainly because it is usually linked to polluted waste streams. In fact, the waste streams from chemical industry are now strictly controlled and treated before being released into the environment. But this was not always the case in the past and many rivers and surface water bodies were contaminated by the numerous waste streams coming from various chemical plants, as well as other industrial sources. Even though measures were taken to reduce this type of pollution, its effects are still visible.
Household chemicals involve a variety of chemical products and mixtures that can easily become chemical pollutants when released into the environment. Even the everyday detergents are chemical compounds that may pollute our environment! Read the labels of detergent products to confirm that they contain a variety of potentially hazardous chemicals.
The Effects of Chemical Pollution
Chemical pollution can be caused by a variety of chemicals from a variety of sources and can involve a variety of health effects from simple digestive problems to chemical intoxication and sudden death by poisoning. The effects are usually related to the exposure to high amounts of chemicals. Chemical pollution leads to various serious diseases, generally by consuming poisonous food, drinking highly contaminated water, or breathing highly contaminated air.
Chemical intoxication can have severe health effects that may trigger immediate symptoms and diseases or delayed effects which may appear after weeks or months since the exposure occurred. This is based on the type of pollutants and on the amounts to which you are exposed. CAUTION, never assume that all is OK if no health effects appear immediately!
Various chemical pollutants may accumulate in the aquatic sediments over longer periods of time. This means that, if no tests are performed, chemical pollution in the ocean water could pose serious health risks to the ecosystem and ultimately could cause mild or deadly chemical intoxication in humans after the consumption of contaminated fish or seafood. However, there are prevention tips you can follow to minimize exposure to chemical pollution.